Water Resources Constraints in Fruit Production, Water resources in India and Rajasthan, Fruit production in water stress condition, Water harvesting techniques, Measurement of Soil moisture.

1. Credit Seminar
on
Speaker
Pankaj Kumar Meena
Ph.D. Fruit Science
Department of Fruit Science
College of Horticulture & Forestry, Jhalawar
Submitted to -
Prof. Jitendra Singh
Seminar Incharge & Head of Department
Department of Fruit Science
College of Horticulture & Forestry, Jhalawar
Date – 29/08/2019

2. Over View of Presentation
 Introduction
 Water resources of India
 Status of water resources in Rajasthan scenario
 Water quality for fruit production
 Management of water for fruit production
 Conclusion

3. Introduction
 Water resources are source of water that are potentially useful.
 97 % of the water in the Earth is salt water and only 3 % is fresh
water ; slightly over 2/3 of this is frozen in glaciers and polar ice
caps.
 Most of the animals and plants have 60-65 % water in their body.
 In India, out of total rainfall in an area of 3290 lakh ha, a rainfall of
4000 billion cubic meters annually occurs , out of the total ,41% is
lost in evaporation, 40% is lost in runoff , 10% is retained in soil
moisture and 9% seeps in for recharging ground water
cont.

4. A graphical distribution of the locations of water on Earth

5. A. Source of Water (Approximate)
Item Volume ( Million BCM)
Salt water in Oceans 1348
Fresh Water 37.5
B. Source of Fresh Water (Approximate)
Item Volume (000 BCM)
Polar Ice and Glaciers 28200
Ground Water < 800 m deep 3740
800-400 m deep 4710
Lakes and Rivers 127
Others (soil moisture and
atmospheric vapors)
704
World Water Resources at a Glance
Source - CWC

6. Water Resources of India
Water
Resources
Ground
Water
Sallow well
Deep well
Spring
RainWater
Surface
water
Impounding
reservoirs
River and
Streams
Tank, pond
and lakes

7. Ground water availability in India
 Ground water is the water that seeps through rocks, soil and is stored
below the ground.
 Ground water in India is 433 billion cubic meter / year.
 The overall contribution of rainfall to the country’s annual ground
water is 68 % and the share of other resources is 32 %.
 89 % ground water extracted is used in the irrigation sector , making
it highest category users in the country.
 Wells, including dug wells, shallow tube wells and deep tube wells
provide about 61.6 % of water for irrigation , followed by canals
24.5 %.
 Total area equipped for irrigation by ground water is 39425869 ha.

8. Fig. 1. Increase in ground water utilization in irrigation.
Sources: Agricultural Statistics at Glance 2014, Ministry of Agriculture; PRS.

9. Fig. 2. Tube well increasingly being the main source of irrigation
Sources: Agricultural Statistics at Glance 2014, Ministry of Agriculture; PRS.

10. Surface Water Resources in India
 Surface water is collection of water on the ground or in stream, river
lake, wetland or oceans.
 Surface water is naturally replenished by precipitation and naturally
lost through discharge to evaporation and sub - surface seepage into
the ground water.
 The availability of surface water depends upon the precipitation within
the water shade , storage capacity of the water shade ( lakes, wetland
and artificial reservoir), permeability of the soil , runoff, characteristics
of land , timing of precipitation rates etc.
 Total equipped area irrigated by surface water is 22481977 ha. (36.3 %
of total AEI ).

11.  The annual precipitation of India, including snowfall, is estimated at
1200 mm, which is equal to 4000 Km3 or 400 million hactare meters.
 Surface water bodies include rivers, canals, reservoirs, tanks, ponds,
lakes and brackish water.
 In irrigated ecosystem, reservoirs account for 2.1 M ha., tanks and
ponds 2.3 M ha., wells lakes and direct water bodies 1.3 M ha. and
brackish water bodies 1.2 M ha.
 Out of 400 M ha., 215 m ha. of rain water percolates in to the ground
out of which only 50 M ha. - m join the ground water and available
for utilization.

12. Surface Water Resources of India
Surface
Water
Resources
Rivers
225
Canals
237
Lakes
91
Reservoirs
5202
Water shades
3237
Dams
3200
Fig. Average no. of Surface Water Resources of India
Source - CWC

13.  Rajasthan faces one the greatest scarcity of water resources in the
country.
 Rajasthan has 13.88 % of India’s cultivable area, 5.67 % of
population and about 11 % of country’s livestock but it has only
1.16 % of surface water and 1.70 % of ground water Thus, Rajasthan's
10 % of land area has only 1 % of water resources.
 Rajasthan has net cropped area of 183.49 lac hac. Out of this,
approximately 75 % area is rainfed (116.88 lac hac.) and only 25%
is irrigated area (66.61 lac hac.).
 Of the total irrigated area, 0.35 % under fruits and 1.67 % vegetables
in Rajasthan.
Status of water resources in Rajasthan scenario

14.  83 % of available water used for irrigation.
 35 % of crops are irrigated.
 70 % area irrigated through wells and tubewells.
 27 % irrigated through canals.
 The mean annual rainfall in the East and West Rajasthan is about 64.9
and 32.7 mm respectively.
 Surface water potential of the state from internal resources
comprising 14 rainfed river basins is estimated at 15.86 million acre
feet.
 Imported surface water delivered to Rajasthan from other states by
means of several projects under relevant inter -state agreements.

15. Sr. No. Resources Allotted water in
(MAF – Million
acre feet
1 Ganga Canal 1.11
2 Bhakra Canal 1.41
3 Ravi - Beas 8.6
4 Yamuna water 0.91
5 Mahi water 0.37
6 Narmada 0.5
7 Chambal/ Kota barrage 1.6
Total 14.5
The share of Rajasthan in out of state rivers as per various inter –
state agreements
Source – Irrigation Department, Government of Rajasthan, Jaipur.

16.  Ground water availability in Rajasthan is highly variable, depending
on hydrological conditions.
 The limited ground water resources in Rajasthan are increasingly
being exploited for irrigation, industrial and domestic uses.
 In 2011 out of 243 blocks the ground water status as the follow –
Sr. no. Parameter No. of Blocks
1 Over exploited ( over 100 % ) 172
2 Critical ( 90 -100 % ) 25
3 Semi – critical (70-90 %) 20
4 Safe ( less than 70 % ) 24
5 Saline water bodies 2
Total 243

17. Ground water status of Rajasthan

18. Water Quality for Fruit Production
 The Suitability of irrigation water is mainly depends on the amount
and type of salts present in water.
 The main soluble constituents are calcium, magnesium, sodium as
cations and chloride, sulphate, bicarbonate as anions.
 The other ions are present in minute quantities are boron, selenium,
molybdenum, and fluorine which are harmful with excess
concentration of these ions.
 Water quality is determined according to the purpose for which it
will be used. For irrigation water, the usual criteria include salinity,
sodicity, and ion toxicities.
 Various criteria are considered in evaluating the quality of irrigation
water namely –
Salinity hazard Sodium hazard Salt index
Alkalinity
hazard
Permeability
hazard
Specific ion
toxicity hazard

19. Salinity Hazard
Water Class EC (dS m-1) Remarks
C1 – Low salinity 0 – 0.25 Can be used safely
C2 – Medium salinity 0.25 – 0.75 Can be used with moderate
leaching
C3 – High salinity 0.75 – 2.25 Can be used for irrigation purpose
with some management practices
C4 – Very high 2.25 – 5.00 Can not be used for irrigation
purpose
Chloride concentration (me r-1 ) Water Quality
4 Excellent water
4-7 Good water
7-12 Slightly usable
12-20 Not suitable
>20 Not suitable
Chloride concentration of water

20. Sodicity Hazard
 High concentration of sodium are undesirable in water because sodium
adsorbs on to the soil cation exchange sites, causing soil aggregates to
break down (deflocculation), sealing the pores of the soil and making it
impermeable to water flow.
 The sodicity hazard of irrigation water is usually evaluated by :
 Sodium Adsorption Ratio (SAR)
 Sodium to calcium activity ratio (SCAR)
 Sodium ratio
Magnesium
 A harmful effect on soils appears when Ca : Mg ratio decline below
50.

21. Sulphate
Eaton proposed three classes for sulphate –
< 4 me l-1 Excellent water
4-12 me l-1 Good to injurious
>12 me l-1 Injurious to unsatisfactory
Boron
 The permissible limits of boron in irrigation water are:
Class Crops Remarks
Sensitive Semi tolerant Tolerant
Very Low <0.33 <0.67 <1.00 For safely use
Low 0.33-0.67 0.67-1.33 1-2.0 Can be
managed
Medium 0.67-1.00 1.33-2.00 2.0-3.0 Unsuitable
Very High >1.25 >2.50 >3.75 Unsuitable

22. Fluorine
 The concentration of fluoride ranges from traces to more than 10
mg L-1 in natural water, and surface water do not exceed 0.3 mg
L-1 unless they are polluted.
 Irrigation with fluoride saline water ( upto 25 mg L-1 ) has not been
been found to affect crop yield.
 At present , the average concentration of fluoride has not been
observed to be very high (10 mg L-1 ).
Nitrate
NO3 me l-1 < 5 No problem
5-30 Intensity of problem is
moderate
>30 Intensity of problem is severe

23. Lithium
 Lithium is trace element may be found in most of saline ground water
and irrigated soils.
 It has been found that 0.05-0.1 ppm of lithium in water produce toxic
effects on growth of citrus.
 It has also been reported that saline soils of varying degrees found in
India contain lithium upto 2.5 ppm. Fortunately, the germination of
majority of crops is not affected with this level of lithium content.
 Lithium disrupts numerous metabolic processes such as
photosynthesis, DNA biosynthesis and enzyme activation in plants

24. Management practices for poor quality of water
 Application of gypsum
 Alternate irrigation strategy
Fertilizer application
 Method of irrigation
 Crop tolerance
 Method of sowing
 Drainage

25. Management of water for fruit production
 Irrigation Water Management
 Water Harvesting
 Crop Tolerance
 Water Monitoring Techniques
 Remote sensing of plant water status

26. Irrigation water management for fruit crops
 Irrigation Scheduling –
 Scientific irrigation scheduling is a technique providing knowledge on
correct time and optimum quantity of water application at each
irrigation to optimize crop yields with maximum water use efficiency
and at the same time ensuring minimum damage to the soil properties.
 It enables the farmer to schedule water rotation among the various
fields to minimize crop water stress and maximize yields.
 It results in additional returns by using the “Saved” water to irrigate
non-cash crops.
 It minimize water logging problems and assists in controlling root-
zone salinity problems.

27. Irrigation Scheduling Criteria
Soil Water Regime
• Feel and Appearance
• Depletion of Available
soil moisture
• Soil moisture tension
Climatological
• Cumulative Pan
• Evaporation
• IWE/CPE Ratio
Plant indices
• Visual symptoms
• Soil cum sand mini plot
• Plant Population
• Growth rate
• RWC
• Plant water potential
• Canopy temperature
• Indicator Plants
• Critical growth stages
Irrigation Scheduling Criteria

28.  Irrigation depth for various fruits crop –
Crops Depth to irrigate (cm)
Apple 90
Cherry 60
Grape 90
Peach 60
Pear 60
Raspberries 60
Straw berries 30

29.  Water requirement estimation in fruit crop -
Fruit No. of irrigation
F
e
b
Ma
rch
-
Ap
ril
M
a
y
Ju
ne
July
–
Sep.
Oc
tob
er
No
v.-
Jan
To
tal
Quantit
y of
water
(cm)
Critical period
Aonla - - 2 2 2 - 2 2 10 60 April – June
Oct.- Dec.
Apple
and
Pear
- 1 3 3 3 5 1 3 19 114 April – Aug.
Oct. – Feb.
Bana
na
2 4 4 4 4 3 2 6 29 174 March - June
Ber 1 1 - - - - - 4 6 36 Nov.- march
Mand
arin
- 2 2 2 1 2 2 3 14 84 March - June
Grape 1 - 3 3 1 - - - 8 48 April - June
Mang
o
1 1 1 1 1 - - 1 6 36 Feb. - June
Papay
a
2 4 4 4 4 1 1 9 29 87 March - June
Source - O.P,Advance in Horticulture, K.L. Chadha

30. Apple Early fruit set, during flower formation, and during final fruit swell
Pear Early fruit set, during flower formation, and during final fruit swell
Peach Early fruit set, during flower formation, and during final fruit swell
Plum Early fruit set, during flower formation, and during final fruit swell
Nectarines Early fruit set, during flower formation, and during final fruit swell
Cherries Early fruit set, during flower formation, and during final fruit swell
Blueberries Berry swell to end of harvest and bud formation for next year crop
Raspberries Bloom and berries are sizing before first picking
Blackberries Bloom and berries are sizing before first picking
Strawberrie
s
At planting, during runner formation, during flower bud formation
before harvest begins
 Critical stages of fruit crops for Irrigation

31.  Deficit Irrigation Technique
 Deficit irrigation is an optimization strategy in whereby net returns are
maximized by reducing the amount of irrigation water; crops are
deliberately allowed to sustain some degree of water deficit and yield
reduction.
 Three main DI strategies can be mentioned –
(A) Sustained Deficit Irrigation (SDI) –
“In which irrigation water used at any moment during the season is
below the crop evapotranspiration (Etc) demand”
(B) Regulated Deficit Irrigation (RDI)
“Full irrigation is applied during drought sensitive physiological stages
(critical periods) of fruit tree and irrigation is limited or even
unnecessary if rainfall provides a minimum supply of water during the
drought tolerant phenological stages (Non- critical periods).
Cont…….

32. (C) Partial Root Drying (PRD)-
“A percentage of crop evapotranspiration is applied to alternate plant
sides, allowing part of the root system to be in contact with wet soil
all the time.”
Fig. 1. Graphic pattern of full irrigation (FI), sustained deficit irrigation (SDI), regulated deficit
irrigation (RDI) and partial root drying (PRD) strategies in fruit trees.
Source - A. Galindo et al. / Agricultural Water Management 202

33. Selection of efficient irrigation system
 IRRIGATION METHODS
 Surface Irrigation: Just flooding water. About 90% of the irrigated
areas in the world are by this method.
 Sprinkler Irrigation: Applying water under pressure. About 5 % of
the irrigated areas are by this method.
 Drip or Trickle Irrigation: Applying water slowly to the soil ideally
at the same rate with crop consumption.
 Sub-Surface Irrigation: Flooding water underground and allowing it
to come up by capillarity to crop roots.

34. Topic Flood Farrow Sprinkler Drip
Evaporation loss High High Medium Minimum
Wetting of the
foliage
High Medium High Minimum
Water
consumption by
weeds
High High High Minimum
Surface drainage High High Medium Minimum
Control of
irrigation depth
Minimum Minimum Medium High
Crop yield/unit of
applied water
Minimum Minimum Medium High
Uniformity in the
crop yield
Little Medium Medium High
Soil aeration Minimum Little Little High
Interference of
other tasks by the
irrigation method
High High High Low
Application of
fertilizers and
pesticides through
the irrigation
Minimum Minimum Moderate High
Comparison of Irrigation Methods
Continue……

35. Topic Flood Farrow Sprinkler Drip
Labor cost High High Moderate Moderate
Leveling of the
land is
required
High High Low Minimum
Automation of
the system
Low Low High High
Energy
Requirement
Low Low High High
Quality of
water
Minimum Minimum Moderate High
Use of filters Minimum Minimum Moderate High
Control of
disease and
pest
Minimum Minimum Moderate High

36. Water Harvesting
Water
harvesting for
horticulture
Micro-
catchment
WH
Roof top &
Court yard
systems
On – Farm
System
Macro-
catchment
WH
Long – slopes
Water
Harvesting
Flood water
Harvesting

37.  Rain Water Harvesting
 Rain water harvesting is the accumulating and storing of rain water by
artificial methods for further utilization.
 Methods –
(A) Roof top harvesting
(B) Run off harvesting
 These method can be selected considering the purpose, the type and
quantity of storage, catchment state.

38.  Watershade Management
 A watershade is defined as any spatial area from which runoff from
precipitation is collected and drained through a common point or
outlet.
 Types of watershade –
watershade is classified depending upon the size, drainage , shape and
land use pattern.
Types of
watershade
Macro
watershade
> 50.000
hec.
Sub
watershade
10,000 –
50,000 hec.
Milli
watershade
1000 –
10000 hec.
Micro
watershade
100 – 1000
hec.
Mini-
watershade
1 – 100
hec.

39.  Traditional Types of Water Harvesting Methods
 KULS
 Water channel found in precipitious
mountain areas. eg. – Himachal
pradesh and Jammu.
 VIRDAS
 Shallow wells dug in low depressions
called Jheels (tanks). eg. – Great Rann
of Kutch in Gujrat

40.  BAMBU DRIP IRRIGATION
 Tapping of stream & spring water
using bamboo pipes to irrigate
plantations. eg. Meghalaya
 ERI
 These are tanks to collect water,
prevent soil erosion and wastage
of run off. eg. Tamil Nadu
 KUNDS
 Underground tank developed to
tackle water problems. Eg. –
Rajasthan.

41. Crop Tolerance
 The crops differ in their tolerance to poor quality waters.
 Growing tolerant crops when poor quality water is used for irrigation
helps to obtain reasonable crops yields.
 Relative salt tolerance of fruit crops given in table -
Tolerant (8 mmhos) Date Palm, Guava, Ber,
Pomegranate, Phalsa, Aonla,
Custard apple, Kair.
Semi tolerant (6-3 mmhos) Fig, Grape, Mango, Lemon, Grape
fruit, Orange.
Sensitive (3-1.5 mmhos) Apple, Almond, Peach, Strawberry,
Apricot, Avocado and Plum.

42. Water Monitoring Techniques
 Water quality monitoring can be defined as the programmed process of
sampling, measurements and recordings of various water
characteristics, often with the aim of assessing conformity to specified
objectives.
 Types of water monitoring according to various objectives –
Ambient
Monitoring
• Status and
trend
detection
• Testing of
water quality
standards
• Testing of
loads
Effluent
Monitoring
• Calculation
and controls
of discharge
standards
• Monitoring of
plant
performance
Early
warnings
• Warning of
calamities
• Protection of
downstream
functions
Operational
monitoring
• Monitoring
for
operational
uses such as
irrigation,
industrial use,
inlet for water
treatment
works.

43.  A range of increasingly sophisticated techniques and tools is available
to measure soil water content and to help priorities irrigation choices.
 There is two methods for water monitoring in irrigation is –
(A) Balance sheet
(B) Direct method
 Balance Sheet
 By using known models of evapo-transpiration, together with weather
station data on rainfall temperature, relative humidity, wind speed and
solar energy it is possible to estimate the rate of water loss from a crop,
given the crop cover.
 A balance sheet can then be constructed to schedule irrigation
applications to match water that has been lost via evapo-transpiration.

44.  Direct Method
 Direct method include water monitoring by measuring equipments.
 Following measuring equipments are used in direct method –
(A) Gypsum block and Granular matrix sensor
 Measure water content of soil.
 They do this by measuring the
electrical resistance between two circles
of wire mesh that are embedded in a
porous block of gypsum.
 Granular matrix sensors work in essentially
the same way, but their blocks made of
different sized sand particles rather than of gypsum.

45. (B) Capacitance sensors
 Measures changes in the dielectric permittivity
of the soil by using two metal electrodes.
 The electrodes are inserted or buried in the soil,
or are cylindrical rings inside a plastic access
tube that is inserted vertically into the soil
(C) Tensiometers
 Measures tension to determine soil water content
 This instrument consists of a sealed water- filled
equipped with a vacuum gauge at top end and a
porous ceramic cup on the bottom.
 The useful limit of the tensiometer is about 80 cb.

46. (D) Neutron Probe
 Neutron scattering is a time – tested technique for measuring total
soil water content by volume.
 This apparatus estimates the water content of soil by sensing the
amount of hydrogen that is present in the soil.
 Though organic matter in the soil contains hydrogen, only soil water
content change quickly and makes it possible to calibrate probes to
measure water content.

47. Remote Sensing of Plant Water Status
 Remote sensing using the electromagnetic spectrum to image the land,
ocean and atmosphere.
 Scope - Crop acreage estimation, Crop modeling for yield &
production forecast/ estimation, Crop and orchard monitoring.
 Benefits – Timely availability of crop statistics for decision making
and planning, Crop growth monitoring, Soil status monitoring,
Regular
reports regarding total area under cultivation.
 The use of Infra - red sensors is the closest to commercial exploitation,
this technique involves taking measurements of leaf temperature
using an infra-red thermometer or camera and comparing it with a
reference reading of a standard wet and dry surface.

49. Comparative study of drip irrigation and surface irrigation on yield
parameters and other characters of Mango cv. Dashehari
Treatments No. of
fruits/plant
Weight of
fruit (kg)
Yield
(tone/hac.)
Weed control
(%)
Moisture (%)
T1 194.31 138.70 15.94 13.67 79.10
T2 222.67 142.15 23.30 54.35 80.71
T3 360.27 125.68 20.99 34.56 78.10
T4 293.14 153.25 25.63 65.39 78.53
T5 278.71 146.12 23.34 29.62 80.06
T6 328.53 161.18 28.30 85.98 77.10
T7 239.30 148.19 22.95 32.10 79.60
T8 366.17 163.65 29.80 90.20 77.90
T9 225.23 141.55 20.61 30.73 75.62
CD at 5 % 27.96 4.41 1.89 12.29 0.69
IGAU, Raipur Agrawal et al. (2005)
T1 – Basin irrigation with V- volume of water T2 – Basin irrigation with V- volume of water + plastic mulch
T3 - Drip irrigation with V- volume of water T4 - Drip irrigation with V- volume of water + plastic mulch
T5 – Drip irrigation with 0.8 V – volume of water T6 – Drip irrigation with 0.8 V- volume of water + plastic mulch
T7 - Drip irrigation with 0.6 V – volume of water T8 – Drip irrigation with 0.6 V – volume of water + plastic mulch
T9 - Drip irrigation with 0.4 V – volume of water + plastic mulch

50. Yield increase with drip irrigation system in horticulture crops
Crops Conventional
irrigation (t/ha)
Drip irrigation
(t/ha.)
Yield increase (%)
Banana 57.5 87.5 52
Grape 26.4 32.5 23
Sweet lime 100.0 150.0 50
Pomegranate 55.0 109.0 98
Papaya 13.4 23.5 75
Tomato 32.0 48.0 50
Water melon 24.0 45.0 88
Okra 15.3 17.7 16
Chilies 4.2 6.1 44
Sweet potato 4.2 5.9 39
Irrigation and Water Management Division, Bangladesh Agriculture Research
Institute, Gazipur, Bangladesh Biswas et al. (2015)

51. Comparison of application of fertilizers and fertigation in papaya
Parameter Soil application Fertigation Increase over soil
irrigation (%)
Plant height (cm) 288.3 327.7 -
No. of fruits/ plant 76.4 94.7 23.9
Average fruit
weight (kg)
1.86 2.43 30.6
Fruit length 26.3 29.6 12.7
Fruit circumference
(cm)
43.6 51.4 17.8
TSS (B) 11.2 12.4 10.7
Jayakumar et al. (2001)

52. Crop Yield increase (%) Water Saving (%) Increase in WUE
Banana 52 45 176
Grape 23 48 136
Sweet lime 50 61 289
Pomegranate 45 45 167
Water melon 88 36 195
Water Use Efficiency with Micro Irrigation
Source - Regional Research Centre, Dr. YSR University of Horticulture, Hessarghatta, Karnataka
A. Narayanamoorthy(2004)

53. Conclusion
 The global population is growing fast, and estimates show that with
current practices, the world will face a 40% shortfall between forecast
demand and available supply of water by 2030.
 Due to excessive use and withdrawal of ground water, availability of
water in natural resources is shrinking day by day which create water
scarcity.
 Water harvesting and conservation of rain water may be a useful tool
for surface water saving.
 Application of modern techniques of irrigation, and water saving
technologies in fruit crops as well as other horticulture crops increase
production and quality in limited water availability.

54. References
Regional Research Centre, Dr. YSR University of Horticulture, Hessarghatta, Karnataka A.
Narayanamoorthy,(2004).
A. Galindo et al. / Agricultural Water Management 2012
Agricultural Statistics at Glance 2014, Ministry of Agriculture
Biswas, Sujit & Akanda, Md & Rahman, M. & Hossain, M.A.. (2015). Effect of drip irrigation
and mulching on yield, water-use efficiency and economics of tomato. Plant, Soil and
Environment. 61. 97-102. 10.17221/804/2014-PSE.
Agarawal, N; H.G. Sharma ; S. Agrawal; A. Dixit; P. Dubey, 2005., Comparative study of drip
irrigation and surface method with and without plastic mulching in mangocv. Dashehari,
Haryana-j. of Horticultural sci. 34(2/1): pp 9-11.
Jeyakumar P.; Kumar, N. and SoorianathaSundaram K. 2001.
Fertigation studies in papaya (Carica papayaL.). South
Indian Hort., 49:71-75.
Jeyakumar P.; Kumar, N. and SoorianathaSundaram K. 2001.
Fertigation studies in papaya (Carica papayaL.). South
Indian Hort., 49:71-75.
Jeyakumar P; Kumar, N and SoorianathaSundaram K. 2001. Fertigation studies in papaya (
Carica papaya L.). South Indian Hort., 49:71-75.