Vegetable Production under Changing Climate Scenario; Gardening Guidebook

VEGETABLE PRODUCTION UNDER
CHANGING CLIMATE SCENARIO
st st
(1 September – 21 September)
2012
COMPILED AND EDITED BY
M L Bhardwaj
H Dev Sharma
Manish Kumar
Ramesh Kumar
Sandeep Kansal
Kuldeep Thakur
Shiv Pratap Singh
Dharminder Kumar
Santosh Kumari
Meenu Gupta
Vipin Sharma

FOREWORD
The importance of vegetables in providing balanced diet and nutritional security has
been realised world over. Vegetables are now recognized as health food globally and play
important role in overcoming micronutrient deficiencies and providing opportunities of
higher farm income. The worldwide production of vegetables has tremendously gone up
during the last two decades and the value of global trade in vegetables now exceeds that of
cereals. Hence, more emphasis is being given in the developing countries like India to
promote cultivation of vegetables. Development of hybrid varieties, integrated insect-pest
and diseases management practices, integrated nutrient management and standardizing
improved agrotechniques including organic farming have changed the scenario of
vegetables production in the country. In short, productivity, quality and post harvest
management of vegetables will have to be improved to remain competitive in the next
decades. The major objectives of reducing malnutrition and alleviating poverty in
developing countries through improved production and consumption of safe vegetables will
involve adaptation of current vegetable systems to the potential impact of climate change.
Genetic populations are being developed to introgress and identify genes conferring
tolerance to stresses and at the same time generate tools for gene isolation, characterization
and genetic engineering. Furthermore, agronomic practices that conserve water and protect
vegetable crops from sub-optimal environmental conditions must be continuously enhanced
and made easily accessible to farmers in the developing world. Current, and new,
technologies being developed through plant stress physiology research can potentially
contribute to mitigate threats from climate change on vegetable production. However,
farmers in developing countries are usually small-holders, have fewer options and must rely
heavily on availableresources.Thus, technologies that are simple, affordable, and accessible
must be used to increase the resilience of farms in less developed countries. Finally, capacity
building and education are key components of a sustainable adaptation strategy to climate
change. Hence, topic "Vegetable production under changing climate scenario" chosen
for the present training under Centre of Advanced Faculty Training in Horticulture
(Vegetables) is appropriate and relevant under the present circumstances of agriculture. I am
sure, the lectures delivered by the faculty of this university, invited speakers as well as the
exposure visits conducted during the training might have benefited the participants . Further,
the giving compilation of lectures in the form of compendium to the participants of training
willalsohelpinstrengtheningtheteachingprogrammesintheirrespectiveinstitutionsinthis
area. All the faculty members and staff of the department of Vegetable Science deserve
appreciationfortheefforts madeinthesmoothconductofthetrainingprogramme.
(K R Dhiman)
Vice Chancellor

ACKNOWLEDGEMENTS
Vegetable being an effective alternative to protective food, have become an
essential component of human diet. Although there has been spectacular increase in the
vegetable production from 15 million tonnes during 1950 to 146 million tonnes during
the current year, but we still need to produce more vegetables to meet the minimum
requirement of at least providing 300 g of vegetables/day/captia. The target can only be
achieved through combined use of growing high yielding varieties having resistance to
various biotic and abiotic stresses with improved nutritional quality and matching
agrotechniques by utilizing available resources. Developing countries like India whose
geographical parts comprises of mountainous regions comprising of Himalayas, central
plateau region, northern plains, coastal regions, deltas etc. are particularly vulnerable for
climate change as little change in the climate will disturb the whole ecology and in-turn
the traditional pattern of vegetables being grown in these regions. Latitudinal and
altitudinal shifts in ecological and agro-economic zones, land degradation, extreme
geophysical events, reduced water availability, and rise in sea level are the factors which
effect the vegetable production. Unless measures are undertaken to adapt to the effects of
climatechange, vegetableproduction in the developing countries like India will be under
threat. Hence, the present training programme organised by Centre ofAdvanced Faculty
Training in Horticulture (Vegetables) on "Vegetable production under changing
climate scenario" is important as it will sharpen the focus on production of vegetables
under changing climatic conditions. The Centre of Advanced Faculty Training in
Horticulture (Vegetables) gratefully acknowledges the patronage provided by Dr. KR
Dhiman, Hon'ble Vice-Chancellor of this University. The financial assistance received
from the Indian Council of Agricultural Research in conducting the training and
generating useful instructional material along with assistance for need based post-
graduate research is also highly acknowledged. The Centre also appreciates sincere
efforts of all the resource personnel within and outside this university for interactionwith
the participants. All the faculty members and staff of Department of Vegetable Science,
Deans and Directors of the University, other Statutory Officers and Heads of the
Departments deserve special thanks for their help and co-operation in making this
trainingprogrammeasuccess.
(M L Bhardwaj)
Director, CAFT

Sr.No. Title
1. Effect of climate change on vegetable production in India
ML Bhardwaj
2. Challenges and opportunities of vegetable cultivation under
changing climate scenario
ML Bhardwaj
3. High altitude protected vegetable production
Brahma Singh
4. Protected cultivation of vegetables in Indian plains
Mathura Rai
5. Relevance of conservation agriculture under climate change
RK Sharma
6. Production technology of ginger under changing climate
H Dev Sharma and Vipin Sharma
7. Production technology of turmeric under changing climate
H Dev Sharma and Vipin Sharma
8. Protected cultivation of high value vegetable crops
Manish Kumar
9. Pre and post harvest factors influencing the quality of vegetable
seeds
HS Kanwar and DK Mehta
10. Impact of climate change on quality seed production of important
temperate vegetable crops
Ramesh Kumar, Sandeep Kumar, Ashok Thakur and Sanjeev Kumar
11. Vegetable production and seed production under temperate conditions
Amit Vikram
12. Production technology of cucumber under changed climatic conditions
Ramesh Kumar, Sandeep Kumar, KS Thakur and Dharminder Kumar
13. Production technology of vegetable crops under changing climate
with reference to organic vegetable production
Kuldeep Singh Thakur, Ramesh Kumar and Dhaminder Kumar
Page(s)
1-12
13-18
19-28
29-36
37-43
44-52
53-58
59-62
63-67
68-74
75-82
83-87
88-91
CONTENTS

14. Role of biofertilizers in enhancing the vegetable productivity under
organic farming systems
Kuldeep Singh Thakur and Dhaminder Kumar
15. Production potential of under exploited vegetable crops
Dharminder Kumar, Ramesh Kumar, KS Thakur, Ashok Thakur,
Prabal Thakur and Sandeep Kumar
16. Off-season tomato production in North Western Himalayas under
changing climate
Shiv Pratap Singh
17. Influence of climate change in capsicum production
Santosh Kumari
18. Efficient irrigation management practices in vegetable crops
JN Raina
19. Impact of climate change on vegetable crop production vis a vis
mitigation and adaptation strategies
Satish Kumar Bhardwaj
20. New pathological threats to vegetable crops and their management
under changing climatic conditions
RC Sharma
21. Biotic factors and their management under changing climate
RC Sharma and Meenu Gupta
22. Integrated disease management in cole crops
NP Dohroo
23. Diagnosis and management of vegetable diseases
Sandeep Kansal
24. Integrated disease management in solanaceous and leguminous
vegetables
Sandeep Kansal
25. Disease management scenario in changing climatic conditions
Harender Raj Gautam
26. Eco-friendly techniques for management of diseases in spice crops
Meenu Gupta
27. Integrated pest management in solanceous and leguminous
vegetable crops
KC Sharma
92-94
95-100
101-103
104-107
108-112
113-120
121-123
124-130
131-135
136-142
143-150
151-158
159-166
167-174

28. Judicious use of pesticides to lower residue in vegetable production
RS Chandel, ID Sharma and SK Patyal
29. Management of pollinators of vegetable crops under changing
climatic scenario
R K Thakur and Jatin Soni
30. Vegetable intercropping in sugarcane for greater productivity and
profitability
RK Sharma and Samar Singh
31. Role of crop modelling in mitigating effects of climate change on
crop production
R S Spehia
32. Physiological disorders in vegetable crops: causes and management
Santosh Kumari
33. Weed management in vegetable crops
Dharminder Kumar, Manish Kumar, Ramesh Kumar, KS Thakur,
Amit Vikram and Sandeep Kumar
34. Biochemical constituents and quality attributes in spices
Vipin Sharma and H Dev Sharma
35. Techniques of quality analysis in spices
Vipin Sharma and H Dev Sharma
36.
List of participants
Recent techniques in postharvest management & processing of
vegetables
PC Sharma, Manisha Kaushal and Anil Gupta
175-181
182-188
189-195
196-202
203-208
209-217
218-222
223-227
228-234
i-ii

Effect of Climate Change on Vegetable Production in India
ML Bhardwaj
Department of Vegetable Science
Dr YS Parmar University of Horticulture and Forestry, Nauni-173 230 Solan
A significant change in climate on a global scale will impact vegetable
cultivation and agriculture as a whole; consequently affect the world's food supply.
Climate change per se is not necessarily harmful; the problems arise from extreme
events that are difficult to predict. More erratic rainfall patterns and unpredictable
high temperature spells consequently reduce crop productivity. Developing
countries in the tropics will be particularly vulnerable. Latitudinal and altitudinal
shifts in ecological and agro-economic zones, land degradation, extreme
geophysical events, reduced water availability, and rise in sea level and salinization
make it difficult to cultivate the traditional vegetables in particular zones in the
world. Unless measures are undertaken to mitigate the effects of climate change,
food security in developing countries will be under threat and will jeopardize the
futureof thevegetablegrowers inthesecountries.
Vegetables are the best resource for overcoming micronutrient deficiencies
and provide smallholder farmers with much higher income and more jobs per hectare
than staple crops. The worldwide production of vegetables has doubled over the past
quarter century and the value of global trade in vegetables now exceeds that of
cereals.
Vegetables are generally sensitive to environmental extremes, and thus high
temperatures and limited soil moisture are the major causes of low yields and will be
furthermagnifiedbyclimatechange.
Environmentalconstraints limitingvegetableproductivity
Environmental stress is the primary cause of crop losses worldwide, reducing
average yields for most major crops by more than 50%. The tropical vegetable
production environment is a mixture of conditions that varies with season and region.
Climatic changes will influence the severity of environmental stress imposed on
vegetable crops. Moreover, increasing temperatures, reduced irrigation water
availability, flooding, and salinity will be major limiting factors in sustaining and
increasing vegetable productivity. Extreme climatic conditions will also negatively
impact soil fertility and increase soil erosion. Thus, additional fertilizer application
or improved nutrient-use efficiency of crops will be needed to maintain productivity
or harness the potential for enhanced crop growth due to increased atmospheric CO .2

The response of plants to environmental stresses depends on the plant developmental
stage and the length and severity of the stress. Plants may respond similarly to avoid
one or more stresses through morphological or biochemical mechanisms.
Environmental interactions may make the stress response of plants more complex or
influence the degree of impact of climate change. Measures to adapt to these climate
change-inducedstresses arecriticalfor sustainabletropicalvegetableproduction.
Hightemperatures
Temperature limits the range and production of many crops. In the tropics,
high temperature conditions are often prevalent during the growing season and, with
a changing climate, crops in this area will be subjected to increased temperature
stress. Analysis of climate trends in tomato-growing locations suggests that
temperatures are rising and the severity and frequency of above-optimal temperature
episodeswillincreaseinthecomingdecades.
Tomatoes are strongly modified by temperature alone or in conjunction with
other environmental factors (Abdalla & Verkerk 1968). High temperature stress
disrupts the biochemical reactions fundamental for normal cell function in plants. It
primarily affects the photosynthetic functions of higher plants. High temperatures
can cause significant losses in tomato productivity due to reduced fruit set, and
smaller and lower quality fruits. Pre-anthesis temperature stress is associated with
developmental changes in the anthers, particularly irregularities in the epidermis and
endothesium, lack of opening of the stromium, and poor pollen formation. In pepper,
high temperature exposure at the pre-anthesis stage did not affect pistil or stamen
viability, but high post-pollination temperatures inhibited fruit set, suggesting that
fertilization is sensitive to high temperature stress. Symptoms causing fruit set
failure at high temperatures in tomato; includes bud drop, abnormal flower
development, poor pollen production, dehiscence, and viability, ovule abortion and
poor viability, reduced carbohydrate availability, and other reproductive
abnormalities. In addition, significant inhibition of photosynthesis occurs at
temperatures above optimum, resulting in considerable loss of potential
productivity.
Drought
Unpredictable drought is the single most important factor affecting world
food security and the catalyst of the great famines of the past. The world's water
supply is fixed, thus increasing population pressure and competition for water
resources will make the effect of successive droughts more severe. Inefficient water
usage all over the world and inefficient distribution systems in developing countries
further decreases water availability. Water availability is expected to be highly
sensitive to climate change and severe water stress conditions will affect crop
2

productivity, particularly that of vegetables. In combination with elevated
temperatures, decreased precipitation could cause reduction of irrigation water
availability and increase in evapo-transpiration, leading to severe crop water-stress
conditions. Vegetables, being succulent products by definition, generally consist of
greater than 90% water (AVRDC 1990). Thus, water greatly influences the yield and
quality of vegetables; drought conditions drastically reduce vegetable productivity.
Drought stress causes an increase of solute concentration in the environment (soil),
leading to an osmotic flow of water out of plant cells. This leads to an increase of the
solute concentration in plant cells, thereby lowering the water potential and
disrupting membranes and cell processes such as photosynthesis. The timing,
intensity, and duration of drought spells determine the magnitude of the effect of
drought.
Salinity
Vegetable production is threatened by increasing soil salinity particularly in
irrigated croplands which provide 40% of the world's food. Excessive soil salinity
reduces productivity of many agricultural crops, including most vegetables which
are particularly sensitive throughout the ontogeny of the plant. According to the
United States Department of Agriculture (USDA), onions are sensitive to saline
soils, while cucumbers, eggplants, peppers, and tomatoes, amongst the main crops
moderately sensitive. In hot and dry environments, high evapo-transpiration results
in substantial water loss, thus leaving salt around the plant roots which interferes
with the plant's ability to uptake water. Physiologically, salinity imposes an initial
water deficit that results from the relatively high solute concentrations in the soil,
+ +
causes ion-specific stresses resulting from altered K /Na ratios, and leads to a build
+ -
up in Na and Cl concentrations that are detrimental to plants. Plant sensitivity to salt
stress is reflected in loss of turgor, growth reduction, wilting, leaf curling and
epinasty, leaf abscission, decreased photosynthesis, respiratory changes, loss of
cellular integrity, tissue necrosis, and potentially death of the plant. Salinity also
affects agriculture in coastal regions which are impacted by low-quality and high-
saline irrigation water due to contamination of the groundwater and intrusion of
saline water due to natural or man-made events. Salinity fluctuates with season,
being generally high in the dry season and low during rainy season when freshwater
flushing is prevalent. Furthermore, coastal areas are threatened by specific, saline
natural disasters which can make agricultural lands unproductive, such as tsunamis
which may inundate low-lying areas with seawater. Although the seawater rapidly
recedes, the groundwater contamination and subsequent osmotic stress causes crop
losses and affects soil fertility. In the inland areas, traditional water wells are
commonly used for irrigation water in many countries. The bedrock deposit contains
salts and the water from these wells are becoming more saline, thus affecting
irrigatedvegetableproductionintheseareas.
3

Flooding
Vegetable production occurs in both dry and wet seasons in the tropics. However,
production is often limited during the rainy season due to excessive moisture brought
about by heavy rain. Most vegetables are highly sensitive to flooding and genetic
variation with respect to this character is limited, particularly in tomato. In general,
damage to vegetables by flooding is due to the reduction of oxygen in the root zone
which inhibits aerobic processes. Flooded tomato plants accumulate endogenous
ethylene that causes damage to the plants. Low oxygen levels stimulate an increased
production of anethylene precursor, 1-aminocyclopropane-1-carboxylic acid
(ACC), in the roots. The rapid development of epinastic growth of leaves is a
characteristic response of tomatoes to water-logged conditions and the role of
ethylene accumulation has been implicated. The severity of flooding symptoms
increases with rising temperatures; rapid wilting and death of tomato plants is
usuallyobservedfollowingashort periodoffloodingathightemperatures.
TheNeedforAdaptation toClimateChange
Potential impacts of climate change on agricultural production will depend
not only on climate per se, but also on the internal dynamics of agricultural systems,
including their ability to adapt to the changes. Success in mitigating climate change
depends on how well agricultural crops and systems adapt to the changes and
concomitant environmental stresses of those changes on the current systems.
Farmers in developing countries of the tropics need tools to adapt and mitigate the
adverse effects of climate change on agricultural productivity, and particularly on
vegetable production, quality and yield. Current, and new, technologies being
developed through plant stress physiology research can potentially contribute to
mitigate threats from climate change on vegetable production. However, farmers in
developing countries are usually small-holders, have fewer options and must rely
heavily on resources available in their farms or within their communities. Thus,
technologies that are simple, affordable, and accessible must be used to increase the
resilience of farms in less developed countries. AVRDC – The World Vegetable
Center has been working to address the effect of environmental stress on vegetable
production. Germplasm of the major vegetable crops which are tolerant of high
temperatures, flooding and drought has been identified and advanced breeding lines
are being developed. Efforts are also underway to identify nitrogen-use efficient
germplasm. In addition, development of production systems geared towards
improved water-use efficiency and expected to mitigate the effects of hot and dry
conditions in vegetable production systems are top research and development
priorities.
4

EnhancingVegetableProduction Systems
Various management practices have the potential to raise the yield of
vegetables grown under hot and wet conditions of the lowland tropics.AVRDC –The
World Vegetable Center has developed technologies to alleviate production
challenges such as limited irrigation water and flooding, to mitigate the effects of
salinity, and also to ensure appropriate availability of nutrients to the plants.
Strategies include modifying fertilizer application to enhance nutrient availability to
plants, directdeliveryof water to roots (drip irrigation),graftingto increaseflood and
disease tolerance, and use of soil amendments to improve soil fertility and enhance
nutrientuptakeby plants.
Water-saving irrigationmanagement
The quality and efficiency of water management determine the yield and quality
of vegetable products. The optimum frequency and amount of applied water is a
function of climate and weather conditions, crop species, variety, stage of growth and
rooting characteristics, soil water retention capacity and texture, irrigation system
and management factor. Too much or too little water causes abnormal plant growth,
predisposes plants to infection by pathogens, and causes nutritional disorders. If
water is scarce and supplies are erratic or variable, then timely irrigation and
conservation of soil moisture reserves are the most important agronomic
interventions to maintain yields during drought stress. There are several methods of
applying irrigation water and the choice depends on the crop, water supply, soil
characteristics and topography. Application of irrigation water could be through
overhead, surface, drip, or sub-irrigation systems. Surface irrigation methods are
utilized in more than 80% of the world's irrigated lands yet its field level application
efficiency is often 40-50%. To generate income and alleviate poverty of the small-
holder farmers in developing countries, AVRDC – The World Vegetable Center and
other institutions promote affordable, small-scale drip irrigation technologies
developed by the International Development Enterprises (IDE). Drip irrigation
delivers water directly to plants through small plastic tubes. IDE states that water
losses due to run-off and deep percolation are minimized and water savings of 50-
80% are achieved when compared to most traditional surface irrigation methods.
Crop production per unit of water consumed by plant evapo-transpiration is typically
increased by 10-50%. Thus, more plants can be irrigated per unit of water by drip
irrigation, and with less labor. In Nepal, cauliflower yields using low-cost drip
irrigation were not significantly different from those achieved by hand watering;
however the long-term economic and labor benefits were greater using the low-cost
drip irrigation. The water-use efficiency by chili pepper was significantly higher in
drip irrigation compared to furrow irrigation, with higher efficiencies observed with
high delivery rate drip irrigation regimes (AVRDC 2005). For drought tolerant crop
5

like watermelon, yield differences between furrow and drip irrigated crops were not
significantly different; however, the incidence of Fusarium wilt was reduced when a
lower drip irrigation rate was used. In general, the use of low-cost drip irrigation is
cost effective, labor-saving, and allows more plants to be grown per unit of water,
therebybothsavingwaterandincreasingfarmers'incomesatthesametime.
Culturalpracticesthat conservewaterand protectcrops
Various crop management practices such as mulching and the use of shelters
and raised beds help to conserve soil moisture, prevent soil degradation, and protect
vegetables from heavy rains, high temperatures, and flooding.The use of organic and
inorganic mulches is common in high-value vegetable production systems. These
protective coverings help reduce evaporation, moderate soil temperature, reduce soil
runoff and erosion, protect fruits from direct contact with soil and minimize weed
growth. In addition, the use of organic materials as mulch can help enhance soil
fertility, structure and other soil properties. Rice straw is abundant in rice-growing
areas of the tropics and generally recommended for summer tomato production. The
benefits of rice straw mulch on fruit yield of tomato have been demonstrated in
Taiwan (AVRDC 1981). In India, mulching improved the growth of eggplant, okra,
bottle gourd, round melon, ridge gourd, and sponge gourd compared to the non-
mulched.Yields were the highest when polythene and sarkanda (Saccharum spp. and
Canna spp.) were used as mulching materials. In the lowland tropics where
temperatures are high, dark-colored plastic mulch is recommended in combination
with rice straw. Dark plastic mulch prevents sunlight from reaching the soil surface
and thericestraw insulatestheplasticfrom directsunlighttherebypreventingthesoil
temperature rising too high during the day. During the hot rainy season, vegetables
such as tomatoes suffer from yield losses caused by heavy rains. Simple, clear plastic
rain shelters prevent water logging and rain impact damage on developing fruits,
with consequent improvement in tomato yields. Fruit cracking and the number of
unmarketable fruits are also reduced. Elimination of flooding and rain damage, as
well as the reduced air temperature, was responsible for the higher yields of the crops
grown under plastic shelters.Another form of shelter using shade cloth can be used to
reduce temperature stress. Shade shelters also prevent damage from direct rain
impact and intense sunlight. Planting vegetables in raised beds can ameliorate the
effects of flooding during the rainy season (AVRDC 1979, 1981).Yields of tomatoes
increased with bed height, most likely due to improved drainage and reduction of
anoxicstress.
Improvedstress tolerancethrough grafting
Grafting vegetables originated in East Asia during the 20th century and is
currently common practice in Japan, Korea and some European countries. Grafting,
6

in this context, involves uniting of two living plant parts (rootstock and scion) to
produceasinglegrowing plant.
It has been used primarily to control soil-borne diseases affecting the
production of fruit vegetables such as tomato, eggplant, and cucurbits. However, it
can provide tolerance to soil-related environmental stresses such as drought, salinity,
low soil temperature and flooding if appropriate tolerant rootstocks are used.
Grafting of eggplants was started in the 1950s, followed by grafting of cucumbers
and tomatoes in the 1960s and 1970s. it was found that melons grafted onto hybrid
squash rootstocks were more salt tolerant than the non-grafted melons. However,
tolerance to salt by rootstocks varies greatly among species, such that rootstocks
from Cucurbita spp. are more tolerant of salt than rootstocks from Lagenaria
siceraria. Grafted plants were also more able to tolerate low soil temperatures.
Solanum lycopersicum x S. habrochaites rootstocks provide tolerance of low soil
o o
temperatures (10 C to 13 C) for their grafted tomato scions, while eggplants grafted
onto S. integrifolium x S. melongena rootstocks grew better at lower temperatures
o o
(18 Cto21 C)thannon-graftedplants.
Vegetables generally are unable to tolerate excessive soil moisture. Tomatoes
in particular are considered to be one of the vegetable crops most sensitive to excess
water. In the tropics, heavy rainfall with poor drainage induces water-logged
conditions that reduce oxygen availability in the soil thereby causing wilting,
chlorosis, leaf epinasty, and ultimately death of the tomato plants. Genetic variability
for tolerance of excess soil moisture is limited or inadequate to prevent losses.
Research at AVRDC - The World Vegetable Center has shown that many accessions
of eggplant are highly tolerant of flooding. Thus, the Center developed grafting
techniques to improve the flood tolerance of tomato using eggplant rootstocks which
were identified with good grafting compatibility with tomato and high tolerance to
excess soil moisture. Tomato scions grafted onto eggplant rootstock grow well and
produce acceptable yields during the rainy season. In addition to protection against
flooding, some eggplant genotypes are drought tolerant and eggplant rootstocks can
thereforeprovideprotectionagainstlimitedsoilmoisturestress.
DevelopingClimate-ResilientVegetables
Improved, adapted vegetable germplasm is the most cost-effective option for
farmers to meet the challenges of a changing climate. However, most modern
cultivars represent a limited sampling of available genetic variability including
tolerance to environmental stresses. Breeding new varieties, particularly for
intensive, high input production systems in developed countries is required to be
done.
7

Superior varieties adapted to a wider range of climatic conditions could result
from the discovery of novel genetic variation for tolerance to different biotic and
abiotic stresses. Genotypes with improved attributes conditioned by superior
combinations of alleles at multiple loci could be identified and advanced. Improved
selection techniques are needed to identify these superior genotypes and associated
traits, especially from wild, related species that grow in environments which do not
support the growth of their domesticated relatives that are cultivated varieties. Plants
native to climates with marked seasonality are able to acclimatize more easily to
variable environmental conditions and provide opportunities to identify genes or
genecombinationswhichconfersuch resilience.
Toleranceto high temperatures
The World Vegetable Center has developed tomatoes and Chinese cabbage
with general adaptation to hot and humid tropical environments and low-input
cropping systems since the early 1970s. This has been achieved by developing heat-
tolerant and disease-resistant breeding lines. The Center has made significant
contributions to the development of heat-tolerant tomato and Chinese cabbage lines
and the subsequent release of adapted, tropical varieties worldwide. The key to
achieving high yields with heat tolerant cultivars is the broadening of their genetic
base through crosses between heat tolerant tropical lines and disease resistant
temperate or winter varieties. The heat tolerant tomato lines were developed using
heat tolerant breeding lines and landraces from the Philippines (e.g. VC11-3-1-8,VC
11-2-5, Divisoria-2) and the United States (e.g. Tamu Chico III, PI289309).
However,loweryieldsintheheattolerantlinesarestillaconcern.
More heat tolerant varieties are required to meet the needs of a changing
climate, and these must be able to match the yields of conventional, non-heat tolerant
varieties under non-stress conditions. A wider range of genotypic variation must be
explored to identify additional sources of heat tolerance.AnAVRDC - breeding line,
CL5915, has demonstrated high levels of heat tolerance in Southeast Asia and the
Pacific. The fruit set of CL5915 ranges from 15% - 30% while there is complete
o
absenceof fruitsetinheat-sensitivelinesinmeanfieldtemperaturesof 35 C.
Drought toleranceand water-use efficiency
Plants resist water or drought stress in many ways. In slowly developing
water deficit, plants may escape drought stress by shortening their life cycle.
However, the oxidative stress of rapid dehydration is very damaging to the
photosynthetic processes, and the capacity for energy dissipation and metabolic
protection against reactive oxygen species is the key to survival under drought
conditions. Tissue tolerance to severe dehydration is not common in crop plants but
is found in species native to extremely dry environments. Genetic variability for
8

drought tolerance in S. lycopersicum is limited and inadequate. The best source of
resistance is from other species in the genus Solanum. The Tomato Genetics
Resource Center (TGRC) at the University of California, Davis has assembled a set
of the putatively stress tolerant tomato germplasm that includes accessions of S.
cheesmanii, S. chilense, S. lycopersicum, S. lycopersicum var. cerasiforme, S.
pennellii, S. peruvianum and S. pimpinellifolium. S. chilense and S. pennelli are
indigenous to arid and semi-arid environments of South America. Both species
produce small green fruit and have an indeterminate growth habit. S chilense is
adapted to desert areas of northern Chile and often found in areas where no other
vegetation grows. S. chilense has finely divided leaves and well-developed root
system. S. chilense has a longer primary root and more extensive secondary root
system than cultivated tomato. Drought tests show that S. chilense is five times more
tolerant of wilting than cultivated tomato. S. pennellii has the ability to increase its
water use efficiency under drought conditions unlike the cultivated S. lycopersicum
(O'Connell et al. 2007). It has thick, round waxy leaves, is known to produce acyl-
sugars in its trichomes, and its leaves are able to take up dew. Transfer and utilization
of genes from these drought resistant species will enhance tolerance of tomato
cultivars to dry conditions, although wide crosses with S. pennellii produce fertile
progenies, S. chilense is cross-incompatible with S. lycopersicum and embryo rescue
through tissue culture is required to produce progeny plants. Research at AVRDC
and other institutions is in progress to identify the genetic factors underlying drought
tolerance in S. chilense and S. pennellii, and to transfer these factors into cultivated
tomatoes.
Toleranceto salinesoils and irrigationwater
Attempts to improve the salt tolerance of crops through conventional
breeding programs have very limited success due to the genetic and physiologic
complexity of this trait. In addition, tolerance to saline conditions is a
developmentally regulated, stage-specific phenomenon; tolerance at one stage of
plant development does not always correlate with tolerance at other stages. Success
in breeding for salt tolerance requires effective screening methods, existence of
genetic variability, and ability to transfer the genes to the species of interest. Most
commercial tomato cultivars are moderately sensitive to increased salinity and only
limitedvariationexistsincultivatedspecies.
Genetic variation for salt tolerance during seed germination in tomato has
been identified within cultivated and wild species. In pepper, salt stress significantly
decreases germination, shoot height, root length, fresh and dry weight, and yield.
Pepper genotypes Demre, Ilica 250, 11-B-14, Bagci Carliston, Mini Aci Sivri,
Yalova Carliston, and Yaglik 28 can be useful as sources of genes to develop pepper
9

cultivars with improved germination under salt stress. Related wild tomato species
have shown strong salinity tolerance and are sources of genes as coastal areas are
common habitat of some wild species. Studies have identified potential sources of
resistance in the wild tomato species S. cheesmanii, S. peruvianum, S pennelii, S.
pimpinellifolium, and S. habrochaites. Attempts to transfer quantitative trait loci
(QTLs) and elucidate the genetics of salt tolerance have been conducted using
populations involving wild species. Elucidation of mechanism of salt tolerance at
different growth periods and the introgression of salinity tolerance genes into
vegetables would accelerate development of varieties that are able to withstand high
orvariablelevelsofsalinitycompatiblewithdifferentproductionenvironments.
Climate-Proofingthrough Genomicsand Biotechnology
Increasing crop productivity in unfavorable environments will require
advanced technologies to complement traditional methods which are often unable to
prevent yield losses due to environmental stresses. In the past decade, genomics has
developed from whole genome sequencing to the discovery of novel and high
throughput genetic and molecular technologies. Genes have been discovered and
gene functions understood. This has opened the way to genetic manipulation of
genes associated with tolerance to environmental stresses. These tools promise more
rapid, and potentially spectacular, returns but require high levels of investment.
Many activities using these genetic and molecular tools are in place, with some
successes. National and international institutes are re-tooling for plant molecular
genetic research to enhance traditional plant breeding and benefit from the potential
ofgeneticengineeringtoincreaseandsustaincropproductivity.
QTLsand genediscoveryfortolerancetostresses
Genetic enhancement using molecular technologies has revolutionized plant
breeding. Advances in genetics and genomics have greatly improved our
understandingofstructuralandfunctionalaspectsof plantgenomes.
The use of molecular markers as a selection tool provides the potential for
increasing the efficiency of breeding programs by reducing environmental
variability, facilitating earlier selection, and reducing subsequent population sizes
for field testing. Molecular markers facilitate efficient introgression of superior
alleles from wild species into the breeding programs and enable the pyramiding of
genes controlling quantitative traits. Thus, enhancing and accelerating the
development of stress tolerant and higher yielding cultivars for farmers in
developing countries. Molecular marker analysis of stress tolerance in vegetables is
limitedbuteffortsareunderwaytoidentifyQTLsunderlyingtolerancetostresses.
10

PrioritizingVegetableResearchtoAddress Impact ofClimateChange
It is unlikely that a single method to overcome the effects of environmental
stresses on vegetables will be found.Asystems approach, where all available options
are considered in an integrated manner, will be the most effective and ultimately the
most sustainable, particularly for developing countries in the tropics under a variable
climate. This holistic strategy will need global integration of efforts; the resulting
synergies will produce impact more quickly than the individual institutions working
in isolation could accomplish. For this to succeed, adequate and long-term funding is
necessary, scientific results have to be delivered, best approaches utilized and
effectivemethodssustainedtodeliverglobalpublicgoods for impact.
AVRDC - The World Vegetable Center, as the world's leading international
center focused on vegetable research and development, has expanded its research to
further address the potential challenges posed by climate change. The Center's
success in its major objectives of reducing malnutrition and alleviating poverty in
developing countries through improved production and consumption of safe
vegetables will involve adaptation of current vegetable systems to the potential
impact of climate change. Vegetable germplasm with tolerance to drought, high
temperatures and other environmental stresses, and ability to maintain yield in
marginal soils must be identified to serve as sources of these traits for both public and
private vegetable breeding programs. This germplasm will include both cultivated
and wild accessions possessing genetic variation unavailable in current, widely-
grown cultivars. Genetic populations are being developed to introgress and identify
genes conferring tolerance to stresses and at the same time generate tools for gene
isolation,characterization,andgeneticengineering.
Furthermore, agronomic practices that conserve water and protect vegetable
crops from sub-optimal environmental conditions must be continuously enhanced
and made easily accessible to farmers in the developing world. Finally, capacity
building and education are key components of a sustainable adaptation strategy to
climatechange.
Enhancing adaptation of tropical production systems to changing climatic
conditions is a huge undertaking. It requires the combined efforts of many national
and international institutions and an effective and efficient strategy to be able to
deliver technologies that can mitigate the effects of climate change on the diverse
crops and production systems. The scientific information and technologies
developed through these initiatives must be readily accessible, consolidated and
utilized in a strategic way. This can only be achieved through collaboration,
complementarily, and coordinated objectives to address the consequences of climate
changeon theworld's cropproduction.
11

References
Abdalla AA, Verderk K (1968) Growth, flowering and fruit set of tomato at high
temperature.TheNethJAgricSci16:71-76.
AVRDC (1990) Vegetable Production Training Manual. Asian Vegetable Research
andTrainingCenter.Shanhua,Tainan,447 pp.
AVRDC (1979)Annual Report.Asian Vegetable Research and Development Center.
Shanhua,Taiwan.173 pp.
AVRDC (1981)Annual Report.Asian Vegetable Research and Development Center.
Shanhua,Taiwan.84 pp.
AVRDC (2005) Annual Report. AVRDC – The World Vegetable Center. Shanhua,
Taiwan.
12

Challenges and Opportunities of Vegetable Cultivation
under Changing Climate Scenario
ML Bhardwaj
Department of Vegetable Science
Dr YS Parmar University of Horticulture and Forestry, Nauni-173 230 Solan
The world's farmers are challenged with growing abundant, safe and
nutritious food for an increasing global population in the face of changing climate
and pest pressures.To enable them to continue to produce food sustainably, they need
to have broad access to appropriate innovations, as well as the knowledge and skills
to make these new tools valuable on the farm. India produces 133.5 millions tones of
vegetables from an area of 7.9 million hectares (NHB, 2010).According to statistics
release by Ministry ofAgriculture, there has been 13.5% increase in area and 13.4%
increase in vegetable output during the period 1996 to 2010. India is the second
largest producer of vegetables in the world, next to China. India's share of the world
vegetable market is around 14%. India is endowed with quite a diverse climatic
condition, which enables production of more than 50 indigenous and exotic
vegetables. India ranks first in peas and cauliflower production and is the second
largest producer of onion, brinjal and cabbage. In spite of all these achievements, per
capita consumption of vegetables in India is very low against WHO standards (180
g/day/capita against 300 g/day capita recommended by FAO). Iron deficiency,
anaemia is quite wide spread in our country, the prevalence varying from 45 per cent
in adult males to 70 per cent or more in women and children. There is an urgent need
for providing health security to our population by supplying nutrition through
balanceddiet.
Vegetables are rich source of vitamins, carbohydrates, salts and proteins.
With increased health awareness in the general public and changing dietary patterns,
vegetables are now becoming an integral part of average household's daily meals. In
addition, high population growth rate has also given rise to high demand in basic
dietary vegetables. Increased health awareness, high population growth rate,
changing dietary patterns of increasingly affluent middle class and availability of
packaged vegetables, has therefore generated a year round high demand for
vegetables in the country in general and in major city centres in particular. However,
our farmers have yet not been able to in cash this opportunity and still follow
traditional sowing and picking patterns. This results in highly volatile vegetable
supply market wherein the market is flooded with seasonal vegetables irrespective of
demand presence on one hand and very high priced vegetables in off-season on the

other. Lack of developed vegetable processing and storage facility robs our farmers
from their due share of profit margins. In natural season local vegetables flood the
markets substantially bringing down the prices. In the absence of storage
infrastructure and vegetable processing industry in the country, off-season
vegetablesfarmingistheonlyviableoptionthatcanaddvaluetothefarmerproduce.
There is a huge demand for fresh vegetables in the local as well as
international markets, which includes Europe, Middle East, and Far Eastern markets
but due to their perishable nature it is difficult to export this commodity. The facility
of growing off-season vegetables also allows for growing non-conventional varieties
of vegetables, which are in high demand in the international market. Vegetables can
be cultivated in off-season, with the induction of an artificial technique like
greenhouse technology, in which temperature and moisture is controlled for specific
growth of vegetables. The production of vegetables all around the year enables the
growers to fully utilize their resources and supplement income from vegetable
growing as compared to other normal agricultural crops. Hybrid seeds that provide
higher yield can lead to lower unit cost. Higher prices can be obtained by producing
the right crops, at the right times and of better quality. They may also depend on
negotiating skills and targeting high price buyers. Since, the land holding of farmers
is decreasing, there is a need to increase the productivity of available land, off-season
vegetable farming is a measure through which we can attain higher profit margins
fromthecrop.
Challenges:
Climate change poses significant challenges and negative impacts upon for
the present vegetable production. There is mounting evidence that smallr farmers in
developing countries are experiencing increased climate variability and climatic
change include more extreme events like average means of temperature and
precipitationwhichisclearlylinkedtoincreasedgreenhousegas(GHG) emissions.
Extreme Weather Physiological impact Crops affected
High temperatures in
summer
Reproductive (flower)
development impaired
Peas, Tomatoes, Seed
Production
Crop development and
yield impaired
Vegetable Brassicas,
Tomatoes
Crop quality impaired Tomatoes, Vegetable
Brassicas
High temperatures in
winter
Cold hardiness limited Seed production
14

Global climate change especially erratic rainfall pattern and unpredictable
high temperature spells will reduce the productivity of vegetable crops. Developing
countries in the tropics will be affected very much. Latitudinal and altitudinal shifts
in different agro ecological zones, land degradation, extreme geophysical events,
reducedwateravailability,riseinsealevelandsalinizationarepostulated.
Among vegetable crops, tomatoes are the most important vegetable crops
worldwide and grown over 4 million hectare of land area. Tomato, cabbage, onion,
hot pepper and egg plant are important in Asia. In Asia, yields are highest in the east
because of temperate and sub-temperate climate and the productivity is lowest in the
hot and humid low lands of South East Asia. The extreme climatic conditions will
affect soil fertility and increase soil erosion. So, additional fertilizers application or
improved nutrient efficiency of crop will be needed to harness the potential for
enhanced crop growth due to increased atmosphere CO . In the tropical areas, high2
temperature conditions are prevalent in the growing season and with the changing
climate crops will be subjected to temperature stress. High temperature affects the
photosynthetic functions of plants and cause irregularities in the epidermis and
endothesium, lack of opening of the stromium and poor pollen formation especially
in case of tomato. In pepper, high post-pollination inhibits fruit set. In tomato, overall
productivity is reduced by high temperatures due to bud drop, abnormal flower
development, poor pollen production, dehiscence and viability, ovule abortion, poor
viability, reduced carbohydrate availability, other reproductive abnormalities and
aboveallinhibitionofphotosynthesis.
Unpredictable drought affects world food security and cause great famines.
Insufficient use of water all over the world and inefficient distribution system in
developing countries decrease water availability. High temperature in combination
with low precipitation could reduce the irrigation water availability and increase the
evapo-transpiration leading to severe crop water stress particularly in vegetables
which contain more than 90% water and ultimately influences the yield and quality.
Drought causes an increase in solute concentration in the soil environment leading to
an osmotic flow of water out of the plant cells which subsequently leads to an
increase of solute concentration in plant cells and so, finally lowers the water
potentialanddisrupts membranesandcellprocesses suchasphotosynthesis.
Salt stress in plants is reflected in loss of turgor, growth reduction, wilting,
leaf curling and epinasty, leaf abscission, decrease photosynthesis, respiratory
changes, loss of cellular integrity, tissue necrosis and ultimately death of plants.
Sometimes, vegetable production is also affected by heavy rainfall especially crops
like tomato. Flooding reduces the oxygen level in the root zone inhibiting aerobic
processes. Generally, flooded tomato plants accumulated endogenous ethylene that
causes damage to the plants. Low oxygen levels stimulate an increased of an ethylene
15

precursor, 1-aminocyclopropane-1-carboxlic acid in the roots. In combination with
high temperatures, flooding causes rapid wilting and death of plants. Yield potential
of majority of vegetable crops is affected by various climatic factors like
temperature,solarradiations, humidity,rainfall,wind, drought, salinityetc
Causes of climatechange
·Deforestation
·Fossil fuelconsumption
·Urbanisation
·Landreclamation
·Agriculturalintensification
·Freshwaterextraction
·Fisheriesoverexploitation
·Wasteproduction (Ericksen,2008)
Opportunitiesofvegetableproduction
India is endowed with a wide range of agro-climatic conditions from tropical
to temperate which makes it ideal for off-season vegetable production throughout the
year.The hill states offer most congenial climatic conditions for off-season vegetable
production during summer months for vegetables like tomato, capsicum, peas,
beans, cole crops, root crops and cucumber. The main season vegetables of these
hilly regions become off-season in the plains as result growers fetch lucrative returns
from their produce. Off-season vegetables produced in the hills have a special
significance because of specific flavour, aroma, freshness, prolonged self-life and
keeping quality. These being environment specific are primarily confined to hilly
areas of the country. The increase in area and production under off season vegetables
in the last 3-4 decades may be because of increase in income level of consumers,
change in dietary habit inclusion of more vegetables in food menu, urbanization,
awareness of both farmers and consumers etc. Moreover, there exists a scope for
increasing the off-season exotic vegetable production for domestic and international
markets. Further, off-season vegetable production helps to bridge the seasonal gap
between demand and supply and provides more employment opportunities to
marginalandsmallhillyfarmers.
In Himachal Pradesh, agriculture plays an important role in the economy of
Himachal Pradesh as 67 per cent of the total population depends on agriculture for its
livelihood. Only 11 per cent of the total geographical area is available for agriculture,
out of which 80 per cent is rain-fed and the holdings are small and scattered. Despite
all these barring factors, climate of the state, especially in the hilly regions, is
congenial for the cultivation of many off-season vegetables, horticultural and
floricultural crops. In the valley areas of the district Kullu, the acreage of cereal crops
16

has declined from 59 per cent to 5 per cent but has been recompensed by vegetable
crops over a period from 1990-91 to 2002-03 (Bala and Sharma, 2005). Farmers have
tapped underground water sources through bore wells, tube-wells and hand pumps,
tomeettheirwaterrequirement.
In the state, several vegetables grown in the summer- kharif season are
harvested at a time when they can't be produced in the plains. These off-season
vegetables have a definite market advantage and provide assured better returns to the
farmers. The valley areas of the state have become famous for the production of
quality peas, cabbage, cauliflower, French bean and capsicum. Also, being short-
duration crops, 3-4 crops of vegetables can be taken by the farmers in the mid-hills
per annum to augment their income. According to Thakur (1994) “Off-season
vegetable production and marketing is the most profitable farm business giving very
high production and income to farmers per unit area of land”.Asystem approach will
thus be the most effective and sustainable for the developing countries in the tropics
under a variable climate which will cover collection and improvement of wild
species tolerance to drought, high temperature and other environment stresses using
gene isolation, characterization and genetic engineering, stresses on effective
delivery methodology to transfer technologies and disseminate knowledge and
strategieson capacitybuildingandeducation
Conclusions
·Climate change will lead to more periods of high temperature and periods of
heavyrain.
·Unseasonal or extreme weather will have an increasing impact on crop
production.
·Therearealreadyexamplesofwhattoexpect.
·Modellingcanhelppredictconsequencesandguideadaptation.
·Development of production system, improved varieties with improved water
useefficiency.
·Screeningandvalidationoftheclonedgenesinmodelcrops such as tomato.
·Patentingelitegenesandpromoters
·In India, diverse climatic conditions, available across the country provide
ample opportunity to grow almost all types of vegetable crops, thus making
ourcountrythesecondlargestproducerof vegetables.
0
·An average increase of 1 C could affect the phenology of crop by influencing
degree-day. Understanding, the likely impact of increase in temperature and
CO on vegetable crops is the first step in developing sound adaptation2
strategiestoaddress theadverseimpactofclimatechange.
17

References:
Arya Prem Singh. 2000. Off-season vegetable growing in hills. APH Publishing
Corporation,New Delhi.427p.
Bala Brij, Sharma Nikhil and Sharma R K. 2011. Cost and return structure for the
promising enterprise of off-season vegetables in Himachal Pradesh. Agricultural
EconomicsResearchReview24:141-148.
De L C and Bhattacharjee S K. 2011. Handboook of vegetable crops. Pointer
Publishers;Jaipur.pp. 27-31.
Ericksen P. 2008. Climate Change and Food Security. Environmental Change
InstituteUniversityofOxford. UK.
Ghosh S P. 2012. Carrying Capacity Of IndianAgriculture. Current Science. 102 (6):
889-893.
IPCC. 2001. Climate change 2001: Impacts, adaptation and vulnerability.
Intergovermental PanelonClimateChange.NewYork,USA.
Liliana H. 2011. The Impacts of Climate Change on Food Production; A 2020
Perspective. United Nations Framework Convention on Climate Change. ISBN;
USA.
Mishra G P, Singh Narendra, Kumar Hitesh and Singh Shashi Bala. 2010. Protected
Cultivation for Food and Nutritional Security at Ladakh. Defence Science
Journal61 (2):219-225.
18

High Altitude Protected Vegetable Production
Brahma Singh
Advisor, World Noni Research Foundation, Chennai
Former Director, Life Sciences, DRDO, New Delhi
The topic has two major aspects. First one is high altitudes meaning inhabited
areas 7000 feet above mean sea level. High altitudes are known for difficult
environment from vegetable production point of view. The second one is protected
vegetable production meaning vegetable production using protected agriculture
technologies where ever necessitated. Both the aspects require brief elaboration
beforedescribingdetailsofthetopic.
HIGHALTITUDES
In Indian Himalaya, high altitudes are of two types from their climate point of
view. First one is cold and humid high altitudes spread over mainly in Uttaranchal,
Sikkim, West Bengal and Arunachal Pradesh and other North East States. The other
one is cold arid high altitudes mainly spread over in Jammu and Kashmir-the Ladakh
region and Himachal Pradesh-Lahual-Spiti and Kinnaur area. Himachal Pradesh and
Jammu and Kashmir have sizeable area under cold humid high altitudes also. The
climatic conditions in cold humid and cold arid high altitudes are different
necessitating different type of protected agriculture. Altitudes in Indian Himalayas
range between 200 to more than 5000 meter above mean sea level. Winters in high
altitudes are severe and prolonged restricting vegetable production season from 7 to
2.5 monthsorlessasgivenbelow.
Table-1.Vegetableproduction periodat differentaltitudes
Altitude met ers above
mean sea level
Period Month
2670 April-October 7.0
3000 May-Mid October 5.5
3300 Mid May–Mid
September
4.0
4000 Mid June –August 2.5

Sub-zero temperatures result in snowfall in higher altitudes. It could result in dry
cold or wet along with rainfall or snow. In Ladakh and Lahaul-Spiti cold arid desert
permafrost occurs with frozen upper soil (mostly sandy). In these areas ambient
minimum temperatures are below or near freezing for almost five months. The
relative humidity during this period is in the range of 45-60%. In Leh valley average
minimum temperature from November to April is sub-zero and can be as low as
minus 16 ?C. Wind velocity in the afternoon is very high resulting in dust storm or
snow blizzards.The authors had an opportunity to work in these areas for more than a
decade.Thisarticleis basedmainlyontheirexperienceoncolddesert.
PROTECTEDVEGETABLE PRODUCTION
th
The area under greenhouse cultivation, reported by the end of 20 century
was about 110 ha. in India and world over 275,000 hectare (Mishra, et al 2010).
During last decade this area must have increased by 10 per cent if not more. In
Europe, Spain is leading in protected agriculture with 51,000 ha mostly under low
cost poly houses. In Asia, China has the largest area under protected cultivation, 2.5
M ha under poly house/greenhouse. Protected vegetable production is important
component of protected agriculture. Protected vegetable production is practiced
throughout the world irrespective of altitude of the place since several hundred years.
River bed production of early cucurbits prevalent in India since ages , is protected
agriculture. It involves protection of production stages of vegetables mainly from
adverse environmental conditions such as temperature, hail, scorching sun, heavy
rains, snow etc. In fact the need to protect the crops against unfavorable
environmental conditions led to the development of protected agriculture. This is
now becoming important due to climate change. Greenhouse is the most practical
method of achieving the objectives of protected agriculture, where natural
environment is modified by using sound engineering principles to achieve optimum
plant growth and yield. Besides protected technology has potential to produce more
produce per unit area with increased input use efficiency. There is need to increase
nutritionally rich vegetable production and productivity of seasonal and non-season
crops in our country. Research results have shown that by adopting protected
cultivation productivity of vegetable crops can be increased by 3 to 5 times as
compared to open environment. This aspect needs to be extensively exploited in
India as has been done elsewhere in the world. To promote this Indo-Israel protected
vegetable production projects in the country are serving the purpose. NAIP program
of ICAR is giving due importance to this aspects besides different public and private
organizations. Areas having uncongenial environment for vegetable production can
also be converted into potential vegetable production centers with the help of
protected agriculture technologies and techniques as has been discussed in this
article. Needless to emphasize that better quality produce is obtained under protected
conditions.
20

ADVANTAGES OFPROTECTEDVEGETABLE CULTIVATION
Protected vegetable production can reduce the amount of water and chemicals used
in production of high value vegetables compared to open field conditions. The
comparativeadvantagesare:
1. Vegetables can be produced year round regardless of season.Adverse climate
for production of vegetables can be overcome by different systems of
protectedproduction.
2. Multiplecroppingon thesamepieceof landis possible.
3. Offseason productionofvegetablestogetbetterreturntogrowers isfeasible.
4. It allows production of high quality and healthy seedlings of vegetables for
transplanting in open field supporting early crop, strong and resistant crop
stands.
5. Protective structures provide protection to high value crops from
unfavorableweatherconditions,pests anddiseases.
6. Use of protected vegetable cultivation can increase production by more than
fivefolds andincreaseproductivityperunitofland,water,energyandlabour.
7. Protected cultivation supports the production of high quality and clean
products.
8. It makes cultivation of vegetables possible in areas where it is not possible in
openconditionssuchashighaltitudesdeserts.
9. It makes vertical cultivation of vegetables possible using technologies like
hydroponics,aeroponicsetcanduse of verticalbedsforproduction.
10. Disease free seed production of costly vegetables becomes easy under
protectedstructures.
LIMITATIONS
1. Manual or hand pollination in cross pollinated vegetables like cucurbits or
developmentoftheirparthenocarpichybrids/varieties.
2. Expensive,short lifeandnon-availabilityof claddingmaterials.
3. Lackofappropriatetoolsandmachinery.
4. Structure cost initially looks unaffordable. Farmers with zero risk
affordabilitydonotcomeforward toadoptit.
5. Inadequate support from planners and scientists- suitable varieties/hybrids
21

and their production packages for protected production systems are either
not available or very few. Protected structures in use are not scientifically
designed;hencepotentialsof structurearenotfullyexploited.
METHODS OF PROTECTED VEGETABLE PRODUCTION IN HIGH
ALTITUDES
The major protected cultivation methods at high altitudes of India in vogue are use
of:
1. Polyhouses/Greenhouse/nethouse/shadehouse
2. Lowtunnels/rowCovers
3. PlasticMulching
POLYHOUSES/GREENHOUSES/NETHOUSES/SHADEHOUSES
Poly house/greenhouse is a framed structure having 200 micron (800 gauges)
UV stabilized transparent or translucent low density polyethylene or other claddings
which create greenhouse effect making microclimate favorable for plant growth and
development. Structure is large enough to permit a person to work inside. The
structure can be made in different shape and size using locally available materials or
steelor aluminumorbricksortheircombinationsfor itsframe.
In Ladakh poly houses are made above ground ( poly house), underground
(soil trench) and a combination of two (polyench). Above ground poly houses are
generally made of mud wall or unbaked brick wall on three sides. North side wall is
made 7 feet high, east and west side walls are made with gradual slope to south
having entrance on either side. Southern side is covered with polyethylene supported
on locally available willow or poplar wood frames. Water for irrigation is stored
insidebutunderground forconvenience.
The underground trench type poly house is made with suitable dimensions,
generally 5-10x3-4x 1m with polyethylene cladding supported on wooden poles or
GI pipes.
A combination of both-construction of poly house above trench, known as
polyench is being found better than both in winter months for production of
vegetables where soil and sun heat is harnessed for maintaining required higher
temperatureinside.Polyenchcanbesingleor doublewalled.
Poly houses are constructed using GI pipe of 25-75 mm diameter with a wall
thickness of 2mm. These structures are fastened by welding, nuts and bolts or
22

clamped. Foundation for posts, size of hoops and perlins are worked out on
engineering principles. Good cladding material (low density polyethylene, diffused
or relatively translucent films, cross laminated, anti-fog, anti-drip, anti-sulphur
types, fiber reinforced plastics, polycarbonates etc) is essential to ensure good life of
greenhouse. Poly carbonate and FRP cladding green houses have also been found
useful for covering large area.. During winter month solar heat is harnessed for
production of leafy and other vegetables and vegetable nursery. The temperatures
inside different protected structures during winter are higher than open field to the
extentof supportingplantlife.
Insect proof net and shading materials are used to keep insects at bay and to
lower temperatures in summer if considered necessary. Net and shade houses are
used for vegetable production as protected structures elsewhere in lower altitudes in
thecountry.
LOWTUNNELS ORROWCOVERS
Transparent plastic films or nets are stretched over low (1m or so) hoops
made of steel wires, bamboo or willow twigs or cane or any other locally available
suitable material to cover rows of plants in the field providing protection against
unfavorable environment like low temperature, frost, wind, insect-pests etc.
Different types of claddings are available in the market. Low tunnels with plastic
mulch and drip irrigation are becoming popular for several vegetable crops
production.
PLASTIC MULCHING
Mulching is a practice of covering soil around plants which makes growing
conditions more favorable by conserving soil moisture, maintaining higher soil
temperature, preventing weeds and allowing soil micro flora to be favorably active.
In other areas organic mulches such as leaves, bark, peat, wooden chips, straw etc are
used but in high altitudes particularly in arid high altitudes plastic is used for
mulching which has unimaginably significantly contributed to vegetable production
there.
Plastic mulching is one of the widely used practices in protected agriculture
particularlyinvegetableproduction.Ithas followingadvantages:
1. Itconservessoilmoistureby preventingwaterevaporationfromit.
2. Itpreventsgerminationof annualweeds becauseofitsopaqueness.
3. Plastic mulches maintain a warm temperature during night which facilitates
an early establishment of seedlings by strong root system or germination of
seeds.
23

4. Soilwatererosiopnis minimized.
5. Plastic mulches serve for longer period. They can be used for more than one
season.
6. Provides cleanercropproduce.
7. Moreincomethroughearly,higherandqualityyields.
CONTRIBUTION OF PROTECTED CULTIVATION ON ARID HIGH
ALTITUDEVEGETABLE PRODUCTION
Arid high altitudes of Ladakh and Lahaul and Spiti in early sixties used to
grow root vegetables like radish, turnip, carrot, beet root; potato and mongol palak
(beet leaf). After Chinese aggression (1962), induction of Indian defence forces in
these areas necessitated local production of different vegetables. Defence Research
and Development Organization (DRDO) through its laboratory, Field Research
Laboratory now Defence Institute of High Altitude Research, Leh did pioneering
research. With the help of protected agriculture technologies it could have been
possible to grow now all short of vegetables there during agriculture season (May to
September or mid October). Perhaps first glass house in high altitudes of the country
was erectedinLeh(11500 ftamsl)in1964.
Some of the major contributions made by DRDO in developing protected
vegetableproductiontechnologiesareas follows:
1.Protected vegetable nursery production making cultivation of several
vegetablespossible
Early production of vegetable nursery under different protected structures
during March and April ( minimum atmospheric temperature is sub-zero) and
transplanting them in May and June with and without plastic mulch extended
agriculture period and made possible cultivation of cabbage, cauliflower, knoll-khol,
broccoli, brussel's sprouts, tomato, brinjal, chili, capsicum and onion possible. Use
of plastic mulch enabled early, quality and higher yield of these vegetables. In
mulched crop low pressure (gravity/slope) drip irrigation and fertigation is possible
as experimented by DRDO. In this way most of the vegetables are being grown on
large scale making the area surplus in cabbage, something unbelievable. Early and
late production of vegetables with the help of protected technology has also been
standardized which extends availability period of locally produced vegetables-an
importantaspectthere.
2.MakingCucurbits production possible incolddesert
Till early 1990s cucurbits cultivation in open in Ladakh was considered
impossible. But growing seedlings in poly pouch under poly houses during April-
24

May and transplanting them in open field with plastic mulch made it possible to grow
almost all cucurbits in Leh. This has not only improved vegetable basket in the area
but also added variety to food basket of local inhabitants and soldiers. Commercial
production of cucurbits in cold desert of India is now possible through protected
cultivation. Sarda melon imported in large quantity in the country can be produced in
these areas with ease. Production of off season (August and September) muskmelon,
watermelon etc in open fields has also become possible. An early crop of cucurbits
likesquash, longmelonetcis alsotakeninpolyhouses.
3.Sub-zero atmospherevegetableproduction
As stated earlier during winter these areas remain cut off with main land due
to heavy snow fall. Only air communication is on during winter months. Through air
transportation of bulky and perishable commodities like vegetables is not only
expensive but very difficult. In Ladakh sector Army alone spends several crores of
rupees only on transportation of vegetables. Cost of transportation is more than the
cost of vegetables. Hence local production through protected cultivation is being
successfully promoted there. This is being encouraged by harnessing solar energy
both thermal and photovoltaic and making heating of greenhouses possible. The
geothermal energy sources available in the area are potential source of heating
greenhouses.Remotenessofthesesources iscominginthewayof theirexploitation
4.VegetableSeedproduction
Seed production of biennial crops like temperate varieties of cole crops, root
crops, and onion used to take two years or 18 months in these areas. First year normal
crop is grown and stored underground during long winters. Second year in summer
they are planted for seed production. By the protected agriculture technology now it
has become possible to produce seeds of these varieties in half the time by raising
early crop under protected structure and transplanting them in open fields for seed
production. Pusa Himani radish, long day onions, Nantes carrot and others respond
well to this technique. Production of seeds of temperate varieties of vegetables in
Indiaisaproblemduetolackofconsortedresearchanddevelopmentefforts?
FutureProspects
To ensure nutritional security along with food security to the ever growing
population of the country it is essential to double production of vegetable crops in the
country. Major constraint is increased pressure on cultivablelands near metros where
vegetables are generally grown. This is due to urbanization and industrialization
which is also essential. Therefore, it is at most necessary to improve the productivity
of vegetables adopting protected cultivation in the country in general and high
altitudesinparticular.
25

Protected cultivation of vegetables in high altitudes of Himalaya has been practiced
successfully indicating its potential to deal with conditions created by climate
change scenario in the country. Protection against adverse climatic conditions for
plant growth has become universal necessity. Protection of plant growth and
development against adverse physical (temperature, rain and wind and biological
(insects and diseases) factors through protected agriculture technologies is going to
be uncommon in near future because of climate change and advantages of protected
cultivation. There is need to develop area specific, most appropriate, efficient and
affordable protected structures with cheaper and durable cladding materials.
Emphasis would be shifted on development of suitable varieties and hybrids of
vegetables for protected cultivation under organic and inorganic production
protocols. Vegetable nurseries would be produced under protected structures both at
individual farmer and commercial nurseries level.Tools and machinery for protected
cultivation would be developed and become common. Vertical or multitier farming
of vegetables would be developed to make use of protected space. High altitudes are
likely to be harnessed for large scale vegetable production under protected
structures. Human resource development on protected agriculture and Government
support for its promotion should be taken up through State Agriculture Universities
and department of horticulture. Plastic mulching coupled with drip irrigation in
vegetable production is going to be a common practice because their proven
advantages. There is emphasis on development of suitable varieties of vegetables
which have high production and productivity under protected conditions in high
altitudes and other places. Production protocols of particular variety of a vegetable
like cucumber, capsicum and tomato are being developed for different structures in
differentclimatesandconditions.
Summary
High altitudes in India are reasonably populated with local tribes and troops.
Vegetable production for them during winter months when environment mainly
temperature is unfavorable for their growth, has been discussed. Protected
production technologies or green house technologies developed for these areas such
as use of local poly house, both underground and above ground along with
combination of both have been discussed. Production of leafy vegetables under
subzero atmosphere, cucurbits and almost all vegetables in cold arid high altitudes of
Ladakh using protected agriculture technology has been mentioned in brief.
Production of almost all vegetable crops during limited agriculture season from May
to September in cold desert of Ladakh, considered remote possibility has now
become possible with the help of protected agriculture technologies. Future
prospects of protected cultivation of vegetable crops in high altitudes and elsewhere
havebeenhighlighted.
26

References:
Dhaulakhandi, A. B. and Singh, B. (1999) Winter performance of greenhouse
attachedpassivesolarheatedhutathighaltitude.SESI, Journal9(2):105-114.
Mishra, G. P., Singh, N. and Kumar,H. and Singh, S. B. (2010) Protected Cultivation
for Food and Nutritional Security at Ladakh Defence Science Journal, Vol. 61,
No. 2,March2010, pp. 219-225
NAAS 2010. “ProtectedAgriculture in North-West Himalayas”. Policy Paper No.
47, NationalAcademyofAgriculturalSciences,New Delhi.pp16.
Singh, B. (1995) Vegetable Production in Ladakh. Field Research Laboratory, Leh.
India
Singh, B. and Dhaulakhandi, A. B. (1998). Application of solar greenhouse for
vegetable production in cold desert in renewable energy. Energy Efficiency
PolicyandtheEnvironment.ElsevierScienceLtd,UK, P2511-314
Singh, B., Dwivedi, S K. and Chaurasia, O.P.(2004). Improvement in production and
productivity of horticultural crops in cold arid regions of India. Proceedings of
the first Indian Horticulture Congress, 6-9 November, 2004, The Horticultural
SocietyofIndia,New Delhi,India,viii+764p
Singh, B., Dwivedi, S. K. and Plajor, E. (2000). Studies on suitability of various
structures for winter vegetable production at sub-zero temperatures. Acta Hort.,
517:309-14.
Singh, B., Dwivedi, S. K. and Sharma J. P. (2000). Greenhouse technology for winter
vegetable cultivation in cold arid zones. In: Dynamics of cold arid Agriculture
(EdsJ. P.SharmaandA.A. Mir)KalayaniPublishers, Judhiana.PP279-293.
Singh, B., Dwivedi, S.K., Singh, N. and Paljor, E. (1999). Sustainable Horticulture
practices for cold arid areas. In : The Himalayan Environment. eds. SK Dash & J
Bahadur.New ageInternational (P) Ltd,Publishers – New Delhi.pp235–245.
Singh, B. and Dwivedi, S. K. (2002). Vegetable production potential in Ladakh. In:
Vegetable growing in India. Eds. P. S. Arya and Sant Prakash. Kalyani
Publishers, New Delhi.pp 87-93.
Singh, B., Dwivedi, SK. and Sharma, JP. (2000 a). Greenhouse technology for winter
vegetable cultivation in cold arid zones. In: dynamics of cold arid agriculture.
Eds.J.P.sharmaandA.A. Mir,kalyanipublishers-Ludhiana,pp.279-293.
Singh,B. (1999)Vegetable production in cold desert of India: a success story on solar
greenhouses.Actahorticulture534:205-12.
27

Singh, N. and Singh, B. ( 2003). Ladakh mein sabji utpadan (Vegetable Production in
Ladakh.FieldResearchLaboratory,Leh.pp139
Singh, B. and Singh, N (2011) High altitudes protected cultivation of vegetables.
Seminar on protected cultivation at GB Pant University of Agriculture and
Technology,Pantnagar,UdhamSinghNagar,Uttarakhand.
28

Protected Cultivation of Vegetables
in Indian Plains
Mathura Rai
Former Director, Indian institute of Vegetable Research Varanasi
1/36 Rashmikhand, Shardanagar, Lucknow-226 002, UP
Vegetable growers can substantially increase their income by cultivation of
vegetables under protected condition during off-season as the vegetables produced
during their normal season generally do not fetch good returns due to availability of
these vegetable in the markets. Off-season cultivation of cucurbits under low plastic
tunnels is one of the most profitable technologies under northern plains of India.
Walk-in tunnels are also suitable and effective to raise off-season nursery and off-
season vegetable cultivation due to their low initial cost. Insect proof net houses
provides virus free ideal conditions for productions of tomato, chilli, sweet pepper
and other vegetables mainly during the rainy season. These low cost structures are
also suitable for growing pesticide-free green vegetables. Low cost greenhouses can
be used for high quality vegetable cultivation for long duration (6-10 months) mainly
in peri-urban areas of the country. Polytrenches have also been proved extremely
useful for growing vegetables under cold desert conditions in upper Himalayas in the
country. Poly house/ Greenhouses are frames of inflated structure covered with a
transparent material in which crops are grown under controlled environment
conditions. Greenhouse cultivation as well as other modes of controlled environment
cultivation has been evolved to create favorable micro-climates, which favors the
crop production could be possible all through the year or part of the year as required.
The primary environmental parameter traditionally controlled is temperature,
usually providing heat to overcome extreme cold conditions. However,
environmental control can also include cooling to mitigate excessive temperatures,
light control either shading or adding supplemental light, carbon dioxide levels,
relativehumidity,water,plantnutrientsandpestcontrol.
Status of Greenhouse Cultivation
Commercial greenhouses with climate controlled devices are very few in the
country. Solar greenhouses comprising of glass and polyethylene houses are
becoming increasingly popular both in temperate and tropical regions. In early
sixties, Field Research Laboratory (FRL) of DRDO at Leh attempted solar
greenhouse vegetable production research and made an outstanding contribution to
the extent that almost every rural family in Leh valley possesses a polyhouse these
days. Indian Petro Chemical Corporation Ltd (IPCL) boosted the greenhouse

research and application for raising vegetables by providing Ultra Violet (UV)
stabilized cladding film and Aluminium polyhouse structures. Several private seed
production agencies have promoted greenhouse production of vegetables. In
comparisontoothercountries,Indiahasverylittleareaundergreenhouses.
Classificationofgreenhouse based on suitabilityand cost
a)Low costorlowtechgreenhouse
Low cost greenhouse is a simple structure constructed with locally available
materials such as bamboo, timber stone pillars, etc. The ultra violet (UV) film is used
as cladding materials. Unlike conventional or hi-tech greenhouses, no specific
control device for regulating environmental parameters in-side the greenhouse are
provided. Simple techniques are, however, adopted for management of the
temperature and humidity. Even light intensity can be reduced by incorporating
shading materials like nets. The temperature can be reduced during summer by
opening the side walls. Such structure is used as rain shelter as well as to protect from
low temperature for crop cultivation. Otherwise, inside temperature is increased
when all sidewalls are covered with plastic film. This type of greenhouse is mainly
suitablefor coldclimaticzone.
b) Medium-techgreenhouse
Greenhouse users prefers to have manually or semiautomatic control
arrangement owing to minimum investment. This type of greenhouse is constructed
using galvanized iron (G.I) pipes. The canopy cover is attached with structure with
the help of screws. Whole structure is firmly fixed with the ground to withstand the
disturbance against wind. Exhaust fans with thermostat are provided to control the
temperature. Evaporative cooling pads and misting arrangements are also made to
maintain a favourable humidity inside the greenhouse. As these system are semi-
automatic, hence, require a lot of attention and care, and it is very difficult and
cumbersome to maintain uniform environment throughout the cropping period.
Thesegreenhousesaresuitablefor dry andcompositeclimaticzones.
c)Hi-techgreenhouse
To overcome some of the difficulties in medium-tech greenhouse, a hi-tech
greenhouse where the entire device, controlling the environment parameters, are
supported to function automatically.At present computer based advance technology
with full automaton for temperature, humidity, irrigation control is available which
can be utilized for high value low volume vegetable for local consumption and long
distancesupply.
Shade house
Shade houses are used for the production of plants in warm climates or during
summer months. Nurserymen use these structures for the growth of hydrangeas and
30

azaleas during the summer months. Apart from nursery, flowers and foliages which
require shade can also be grown in shade houses. E.g. Orchids, These shade
structures make excellent holding areas for field-grown stock while it is being
prepared for shipping to retail outlets. Shade houses are most often constructed as a
pole-supported structure and covered with either lath (lath houses) or polypropylene
shade fabric. Polypropylene shade nets with various percentages of ventilations are
used. Black, green, and white colored nets are used, while black colours are the most
preferredas itretainsheatoutside.
Heatingof Polyhouse
Heating is required in winter season. Generally, the solar energy is sufficient
to maintain inner temperature of polyhouse but some times more temperature is
requiredtobesuppliedtosomecrops. For thisfewmethodsareas follows:
i. Constructingatunnelbelowtheearthofpolyhouse.
ii. Coveringthenorthernwallof thehouse by juteclothing.
iii. Coveringwholeofthepolyhousewithjuteclothduringnight
iv. Fittingsolarenergy drivendeviceinpolyhouse.
CoolingofPolyhouse
0
In summer season, when ambient temperature rises above 40 C during day
time the cooling of polyhouse is required by the following measures, not only the
temperaturebutalsorelativehumidityofpolyhousecanalsobekeptwithinlimit.
i. Removingtheinternalairor polyhouseoutofitinanaturalmanner.
ii. Changingtheinternalairintoexternalairbyputtingthefanon.
iii. Installation of cooler on eastern or Western Wall not only keeps temperature
lowbutmaintainsproperhumidityalso.
iv. Running water-misting machine can control the temperature of the
polyhouse
Cladding material
Polythene proves to be an economical cladding material. Now long lasting,
unbreakable and light roofing panels-UV stabilized clear fiber glass and
polycarbonate panels are available. Plastics are used in tropical and sub-tropical
areascomparedtoglass/fiberglass owing totheireconomicalfeasibility.
Plastics create enclosed ecosystems for plant growth. LDPE (low density
polyethylene) / LLDPE (linear low density polyethylene) will last for 3-4 years
comparedtopolythenewithoutUVstabilizers.
31

32
Plantgrowing structures /containersingreenhouse production
The duration of crop in greenhouse is the key to make the greenhouse
technology profitable or the duration of production in greenhouses should be short.
In this context, use of containers in greenhouse production assumes greater
significance. The containers are used for the following activities in greenhouse
production
Advantages of containersingreenhouse production
Increaseinproductioncapacitybyreducingcroptime.
Highqualityof thegreenhouseproduct
Uniformityinplantgrowth withgood vigor
Providequicktakeoffwithlittleornotransplantingshock.
Easymaintenanceofsanitationingreenhouse
Easytohandle,gradeandshiftor for transportation
Betterwaterdrainageandaerationinpotmedia.
Easy to monitor chemical characteristics and plant nutrition with advance
irrigationsystems likedrips.
Dripirrigationand fertigationsystems ingreenhouse cultivation
The plant is required to take up very large amounts of water and nutrients,
with a relatively small root system, and manufacture photosynthates for a large
amount of flower per unit area with a foliar system relatively small in relation to
requiredproduction.
Wateringsystem
Micro irrigation system is the best for watering plants in a greenhouse. Micro
sprinklers or drip irrigation equipments can be used. Basically the watering system
should ensure that water does not fall on the leaves or flowers as it leads to disease
and scorching problems. In micro sprinkler system, water under high pressure is
forced through nozzles arranged on a supporting stand at about 1 feet height. This
facilitateswateringatthebaselevelof theplants.
Equipmentsrequiredfor dripirrigationsysteminclude
i) Apumpunittogenerate2.8kg/cm2pressure
i) Waterfiltrationsystem–sand/silica/screenfilters
iii) PVC tubingwithdripperoremitters
Drippersofdifferenttypesareavailable
i) Labyrinthdrippers

ii) Turbo drippers
iii) Pressure compensating drippers – contain silicon membrane which assures
uniformflowratefor years
iv) Button drippers- easy and simple to clean. These are good for pots, orchards
andareavailablewithsideoutlet/topoutletormicrotubeoutlet
v) Potdrippers–coneswithlongtube
Wateroutput indrippers
a. 16mmdripperat2.8kg/cm2pressure gives2.65 liters/hour(LPH).
b. 15mmdripperat1 kg/cm2pressure gives1 to4 litersperhour
Filters:Dependingupon thetypeofwater,differentkinds of filterscanbeused.
Gravel filter: Used for filtration of water obtained for open canals and reservoirs
that are contaminated by organic impurities, algae etc. The filtering is done by beds
ofbasaltorquartz.
Hydrocyclone:Used tofilterwellorriverwaterthatcarriessand particles.
DiscflitersL:Used toremovefineparticlessuspended inwater
Screen filters: Stainless steel screen of 120 mesh ( 0.13mm) size. This is used for
secondstagefiltrationof irrigationwater.
Fertigationsystem
In fertigation system, an automatic mixing and dispensing unit is installed
which consists of three systems pump and a supplying device. The fertilizers are
dissolved separately in tanks and are mixed in a given ratio and supplied to the plants
throughdrippers.
Fertilizers: Fertilizer dosage has to be dependent on growing media. Soilless mixes
have lower nutrient holding capacity and therefore require more frequent fertilizer
application. Essential elements are at their maximum availability in the pH range of
5.5 to 6.5. In general Micro elements are more readily available at lower pH ranges,
whilemacroelementsaremorereadilyavailableatpH 6 andhigher.
Forms of inorganic fertilizers: Dry fertilizers, slow release fertilizer and liquid
fertilizerarecommonlyused ingreenhouses.
Slow release fertilizer: They release the nutrient into the medium over a period of
several months. These fertilizer granules are coated with porous plastic. When the
granules become moistened the fertilizer inside is released slowly into the root
medium.An important thing to be kept in mind regarding these fertilizers is that, they
should never be added to the soil media before steaming or heating of media. Heating
melts the plastic coating and releases all the fertilizer into the root medium at once.
Thehighaciditywouldburn therootzone.
33

Liquid fertilizer: These are 100 per cent water soluble. These comes in powdered
form. This can be either single nutrient or complete fertilizer. They have to be
dissolvedinwarmwatertodesiredconcentration.
Fertilizerapplicationmethods:
1. Constant feed: sLow concentration at every irrigation are much better. This
provides continuous supply of nutrient to plant growth and results in steady
growth oftheplant.Fertilizationwitheachwateringis referredas fertigation.
2. Intermittent application: Liquid fertilizer is applied in regular intervals of
weekly, biweekly or even monthly. The problem with this is wide variability
in the availability of fertilizer in the root zone.At the time of application, high
concentration of fertilizer will be available in the root zone and the plant
immediately starts absorbing it. By the time next application is made there
will be less availability of nutrient. This fluctuation results in uneven plant
growth rates,evenstress andpoor qualitycrop.
Fertilizerinjectors
This device inject small amount of concentrated liquid fertilizer directly into
thewaterlinesso thatgreenhouse crops arefertilizedwitheverywatering.
Multipleinjectors
Multiple injectors are necessary when incompatible fertilizers are to be used
for fertigation. Incompatible fertilizers when mixed together as concentrates form
solid precipitates. This would change nutrient content of the stock solution and also
would clog the siphon tube and injector. Multiple injectors would avoid this problem.
These injectors can be of computer controlled H.E. ANDERSON is one of the
popularmultipleinjector.
FertilizerInjectors
Fertilizer injectors are of two basic types: Those that inject concentrated
fertilizer into water lines on the basis of the venturi principle and those that inject
using positivedisplacement
A.VenturiPrincipleInjectors
1. Basically these injectors work by means of a pressure difference between the
irrigationlineandthefertilizerstocktank.
a) Themostcommonexampleof thisis theHOZON proportioner.
b) Low pressure, or a suction, is created at the faucet connection of the Hozon at
the suction tube opening. This draws up the fertilizer from the stock tank and
is blended in to the irrigation water flowing through the Hozon faucet
connection.
34

c) The average ratio of Hozon proportioners is 1:16. However, Hozon
proportioners are not very precise as the ratio can vary widely depending on
thewaterpressure.
d) These injectors are inexpensive and are suitable for small areas. Large
amounts of fertilizer application would require huge stock tanks due to its
narrowratio.
B.Positivedisplacementinjectors:
1. These injectors are more expensive than Hozon types, but are very accurate
inproportioningfertilizerintoirrigationlinesregardlessof waterpressure.
2. These injectors also have a much broader ratio with 1:100 and 1:200 ratio
being the most common. Thus, stock tanks for large applications areas are of
manageablesizeandtheseinjectorshavemuchlargerflowrates.
3. Injection by these proportioners is controlled either by a water pump or an
electricalpump.
4. Anderson injectors are very popular in the greenhouse industry with single
andmultipleheadmodels.
a. Ratios vary from 1:100 to 1:1000 by means of a dial on the pump head for
feedingflexibility.
b. Multihead installations permit feeding several fertilizers simultaneously
without mixing. This is especially significant for fertilizers that are
incompatible (forming precipitates, etc.) when mixed together in
concentrated form.
5. Dosatronfeaturevariableratios(1:50to1:500)andaplainwaterbypass
. 6. Plus injectors also feature variable ratios (1:50 to 1:1000) and operates on
waterpressure aslowas7GPM.
7. Gewainjectorsactuallyinjectfertilizerintotheirrigationlinesby pressure.
a. The fertilizer is contained in a rubber bag inside the metal tank.Water
pressure forcesthefertilizeroutofthebagintothewatersupply.
b. Caremustbetakenwhenfillingthebags as theycantear.
c. Ratiosarevariablefrom1:15to1:300.
8. If your injector is installed directly in a water line, be sure to install a bypass
aroundtheinjectorso irrigationsofplainwatercanbeaccomplished.
Pinching
Pinching operation should be done after one month of transplanting. In
general,maintainingthetwoshoots perplanthas beenfound effective.
35

Developingdevicesformonitoringthrough internet
Control and monitoring of environmental parameters inside a Polyhouse
farm, so as to ensure continuous maintenance of favorable crop atmosphere is very
essentia. The concept encompasses data acquisition of thermal process parameters
through a sensor network, data storage, post processing and online transmission of
data to multiple users logged on to their respective web-browsers. Further, control of
process parameters of a Polyhouse (for example, toggle on/off control of pumps and
accessories, louvers and ventilators, air flow rate, sunlight management, etc.) from
one or more remote monitoring stations over the web server in real time is also
integrated. A graphical user interface (GUI) is unified for the ease of operations by
the farming community. System also allows transmission of process parameters,
including emergency alarm signals via e-mail client server or alternatively sending a
SMS on a mobilephone.Aconventionalchathas also been integratedwith the GUI to
add vibrancy to inter-user communication. This feature can be embedded in
upcoming 3G mobile technology. Simulations and video tutorials can also be
integrated in the web server for teaching the farming community. Such integrated
approach greatly widens the socio-economic possibilities for farmers through
interactionwithmoderntechnologicalresources(Sonawane etal.,2008)
References:
Sonawane,Y. R. , Khandekar, S., Mishra , B.K. and Soundra Pandian, K. K. (2008).
Environment Monitoring and Control of a Polyhouse Farm through Internet.
World Bank:IndiaCountryOverview2008 pp1-6
Wani, K.P. Pradeep Kumar Singh, Asima Amin*, Faheema Mushtaq and Zahoor
Ahmad Dar (2011). Protected cultivation of tomato, capsicum and cucumber
under Kashmir valley conditions Asian Journal of Science and
Technology,1(4):056-061.
36

Relevance of Conservation Agriculture
under Climate Change
RK Sharma
Directorate of Wheat Research, Karnal – 132 001, Haryana, India
Agriculture in India was focused on achieving food security through
increased area under high yielding varieties, expansion of irrigation and increased
use of external inputs like chemical fertilisers and pesticides. With the unabated
increase in population, more and more land will be required for urbanization, and
productivity needs to be increased to meet the increasing domestic and industrial
demand. A decline in land productivity has been observed over the past few years.
Moreover, due to indiscriminate use, or rather misuse, of natural resources especially
water has led to groundwater pollution as well as depletion of groundwater resources
(Nayar and Gill 1994). Depleting soil organic carbon status, decreasing soil fertility
and reduced factor productivity are other issues of concern (Yadav 1998). These
evidences indicate the weakening of natural resource base. If we continue to exploit
the natural resources at the current level, productivity and sustainability is bound to
suffer. Therefore, to achieve sustainable higher productivity, efforts must be
focussed on reversing the trend in natural resource degradation by adopting efficient
resourceconservationagriculturepractices.
Laser land levelling is a pre-requisite for enhancing the benefits of the
resource conservation practices. Generally, fields are not properly levelled leading to
poor performance of the crop, because, part of area suffers due to water stress and
part due to excess of water. After laser levelling the field, it has been observed that
yield enhances from 10 to 25 per cent. The higher yields are due to proper crop stand,
uniform water distribution, crop growth and uniform maturity. In addition to higher
yield, the savings of water, a scarce resource, is from 35-45 per cent due to higher
application efficiency, increased nutrient use efficiency by 15-25 per cent, reduces
weed problem and increases the cultivable area by 3 to 6 per cent due to reduction in
arearequiredforbunds andchannels(Jatetal.2004).
Conservation agriculture
Conservation agriculture is much more than just reducing the mechanical
tillage. In a soil that is not tilled for many years, the crop residues remain on the soil
surface and produce a layer of mulch. This layer protects the soil from the physical
impact of rain and wind, conserves soil moisture, moderates soil temperature and
harbours a number of organisms, from larger insects down to soil borne fungi and
bacteria. These organisms help convert the crop residues into humus and contribute
to the physical stabilization of the soil structure and buffering of water and nutrients.

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