Protected cultivation provides many-fold advantages over open field seed production of vegetables. The beauty of vegetable hybrid seed production under protected conditions is that it could be implemented at a micro or macro level depending upon the need, space, and seed crop requirements. This technology is highly productive, amenable to automation, conserves water, fertilizer, and land, and provides the required environment to overcome the biotic and abiotic stress and enhance yield as well as the quality of seeds. Protected cultivation offers a very congenial environment for producing healthy, virus-free, and genetically pure hybrid seed with higher seed yield per unit area.

1. PUNJAB AGRICULTURAL UNIVERSITY
LUDHIANA
Scope Of Vegetable Seed Production
Under Protected Cultivation
Speaker:
Anusha K.R

2. Introduction

3. Second largest producer of vegetables after China in the
world
India is still far behind in average productivity
Limited availability of
quality seeds of released
varieties and hybrids for
large-scale production
High cost of hybrid
seed
High cost of seed is mainly due to low seed yield under open
field condition
196.27 Million Tonne
25.66 Million Hectares

4. Challenges in open-field
• Raising and maintaining healthy and uniform seedlings
• Management of isolation distance
• Poor seed yield
• Poor seed quality
• Lack of trained manpower
• The biotic (viral diseases in tomato, chilli and cucurbits) and abiotic (environmental
factors viz. high and low temperature, frost stresses, rainfall at the time of maturity etc.)
factors have become a major hurdle in quality seed production in open field conditions
affecting growth, flowering, fruit set and seed set & development.
• Suitable areas for quality seed production of important vegetables are also limited
and in these areas too climate change is an imposing threat.
To overcome these, vegetable seed production under protected structures could be
advocated.

5. Protected cultivation
Cropping technique wherein the micro
environment surrounding the plant body
is controlled partially/ fully as per plant
need during their period of growth to
maximize the yield and resource saving

6. Selection criteria of
structures suitable for seed
production

7. Types of structures
• Cages
• Insect proof net houses
• Naturally ventilated greenhouses
• Semi-climate controlled green house
• Climate controlled green houses
• Walk-in tunnels
Selection criteria of protected structures to be used for vegetable seed production
certainty depends upon a few important factors viz., climatic conditions of the area selected
for seed production, type of seed crop, season of seed production and targeted quantity of
seed production.

8. Naturally ventilated greenhouses
• These are partially controlled by opening and closing of roof and side wall
ventilation.
• It provides a controlled and favorable environment, which results in early
harvest of superior quality fruits than that of the net-house.
• Carbon di-oxide released by the plants during the night is consumed by the
plants itself in the morning which increases the photosynthesis rate by nearly 15
times that helps in higher yield in comparison to net-house and open field
conditions.
• It also gives additional protection to the crop from high or uneven rainfall and
frost especially in winter.

9. Used for seed production of tomato, sweet
pepper, parthenocarpic cucumber and
muskmelon etc. both under south and north
Indian conditions
Duration of growing period and seed
yield are less compared to climate
controlled or semi-climate controlled
greenhouses.

10. Insect proof net-houses
• These structures provide the protection against viruses
and other insects like fruit borers during rainy and post
rainy season.
• These structures are well suited to south Indian conditions
during Sept-Feb.
• However, in north India, insect proof net house could be
utilized for production of parental lines seed and hybrid
seed production during summer and kharif successfully
as per the need of crop and demand.
• Compared to all kind of greenhouses the seed yield is less
but,the cost of seed production is also very less.

11. Low cost polyhouses
• These structures are well suited for growing of healthy and virus free seedlings
of seed crop of Open Pollinated varieties and parental lines for hybrid seed
production in plug trays and
• Seed production of sweet pepper, slicing tomato, cherry tomato, parthenocarpic
cucumber, and muskmelon.

12. Seed production practices of
vegetables under protected
structures

13. 1. Raising of healthy nursery for quality seed
production
Growing of healthy and virus free seedlings of varieties and parental lines for hybrid
seed production is important for quality seed production.
Nursery raising
technology
• Multi-celled plastic plug
trays (1.5" cell size)
containing each cell of a
volume of 18-20 cc.
• Coco-peat, vermiculite
and perlite as soil-less
media in 3:1:1 ratio on
volume basis
Favour vigorous root
development
Avoid mechanical damage
to the roots of the seedlings
at the time of transplanting
This technology is economical and suitable for the cucurbits and solanaceous
crops

14. 2. Selection of crops under greenhouse
Genetic capacity:
• It is an important aspect to produce better quality and more quantity in greenhouse
situation.
• For example, in case of cucumber and tomato the parthenocarpic and
indeterminate varieties are suitable for greenhouse cultivation (Kaddi et al. 2014).
• This is required to cope with lack of pollinating agent in greenhouse.

15. 3. Planting
• The sowing of vegetable crops in
rows helps in conducting effective
plant protection measures, roguing
operations and field inspections.
• For hybrids planting of male parent
line and female parent line has to
be done in a definite proportion.

16. 4. Training and pruning
a. Tomato
• Indeterminate tomato varieties are staked and trained
upright.
• Pruning of side branches is done to maintain single stem
or maximum double stem.
• Usually first to fourth cluster at each branch are selected
for emasculation in case of hybrid seed production.

17. b. Sweet Pepper
• Pruning in sweet pepper is normally done to the shoots that
grow on the stem below the first branching.
• The stem structure of pepper is often too weak to take the
load of the fruits up to maturity; hence plants are trained.
• Pepper plants should be trained upright by allowing two
main branches after removal of first terminal bud in a way
to expose the leaves to the maximum light.

18. c. Cucumber
• It requires a supporting system in order to
grow vertically by means of its tendrils.
• They hang down from wire stretched at
height of 1.5 to 2.0 m.
• In Long- fruited cultivars, the side shoots
and fruits on the main stem are removed
up to a height of 60-70 cm.
• The fruits are then allowed to set on the
main stem up to a height of 2 or 3 meter.
• Side shoots up to 2 m length are not
allowed.
• In short-fruited cultivars the fruits and side
shoots of the main stem are removed up
to a height of 40-50 cm.

19. d. Muskmelon
• The single stem training is followed for
muskmelon.
• The plants are trained upright.
• All branches below 6-8 nodes are
removed.
• Female flowers are retained on branches
emerging from 9 to 16 nodes on the main
stem.
• After fruit set, the tips of the branches are
pinched off retaining 2-3 leaves per
branch.
• The top of the main stem is pinched off
after 25 nodes.
• Maximum 3 to 4 fruits are allowed per

20. e. Cluster pruning
• The vegetables which produce fruits in clusters, the number of fruits/cluster decides the good yield
and quality of the fruit and seed.
• It also increases the size of the fruit and uniformity of fruit ripening.
• Typically 4 to 5 good fruits should be retained to get good quality fruit and improve the seed quality.

21. 5. Pollination management
• Due to absence of natural wind in protected structures, supplementing
pollination methods is required.
• Vegetables grown under protected structures should be pollinated everyday by
 Hand pollination
 Electric pollinator
 By bees

25. • In tomato, pollination at 9.00 AM and 5.00 PM is better for higher fruit set and seed
yield.
• However, under naturally ventilated greenhouse conditions, pollination could be done
throughout the day, starting from 8.00 AM, as the fruit set was above 90% and there
was not much variation among the treatments except 7.00 AM which recorded
significantly higher fruit set (53.5%) and seed recovery (4.75%) per plant with 11.00
AM pollination followed by 10.00 AM and 12.00 noon pollinations.
(Manjunath et al 2010)

26. • Bees under open conditions were found to spend less time in a flower when compared to
the net house condition.
• This may be due to the availability of large number of flowers for less number of bees.
• Similar trend was observed in case of Apis mellifera which was reported to spend less
time in broccoli flowers kept in open than in caged conditions (Devkota and Tapa,
2005).
• Since the bees spend longer time in the flowers under protected structures, pollination
and seed set are highly assured with high quality and high yield of seeds.
Importance of bees under protected cultivation

27. 6. Irrigation
• Irrigation at critical stages like sowing, flowering and fruit set, seed filling and seed maturation is
must and given at optimum rate.
• With holding irrigation at harvest promotes earlier and quicker ripening, irrigation can also be used
for staggering and achieving synchronization in vegetable hybrid seed production.
• Over irrigation can promote vegetative growth, lodging, nutrient imbalance while
• Under irrigation delays flowering, stunted growth, reduces seed filling and leads to immature
drying.

28. • In case of cauliflower, there is problem of maintaining and multiplication of potential self-
incompatible lines for the production of F1 hybrid seed.
• Temporary elimination of the self-incompatibility with the use of CO2 gas has solved this
problem.
• The greenhouse closed tightly within 2-6 hours of pollination, and it is treated with 2-5% CO2
gas which allows successful fertilization by temporarily eliminating the self-incompatibility and
bees are allowed to pollinate the crop when it is in bloom.
• Thereby the selfed seeds can be collected for maintaining the lines for further use.
Maintenance and multiplication of self-incompatible line for hybrid seed
production

29. Extension of duration of crop
• In India, seed production of tomato is mostly limited to southern states of the country due
to availability of long period for optimum pollination and fruit set
• In northern plains, during rainy and post rainy season severe incidence of tomato leaf
curl virus (TYLCV) is a major constraint, whereas during winter season extreme low
temperature (from end of November to mid-February) and thereafter, sharp rise in
temperature during summer season is another major limitation for tomato seed
production.
• Therefore hardly mid-February to maximum mid-March is the optimum period for
maximum pollination and fruit setting.
• Undertaking hybrid seed production of tomato under naturally ventilated greenhouse
extended the effective tomato crossing period which was started two weeks before and
extended four weeks beyond the normal crossing period.
• Total number of days available for pollination was almost double under greenhouse
condition in making tomato hybrid seed production highly economical (Patta et al 2013).

30. Major advantages of vegetables seed production under
protected conditions
• High seed yield (generally 2-4 times more) compared to open field in major vegetables.
• Seed Quality is high compared to open field produced seed.
• Isolation distance can be minimized in cross pollinated vegetables.
• Minimization of problem of synchronization of flowering in parental lines
• Maximum plant population can be maintained along with appropriate ratio of male and female parents for
higher hybrid seed yield.
• Duration of seed crop is more under protected conditions when compared with open field seed crops.
• Under adverse climatic conditions seed production is possible which is a difficulty in open field
conditions.
• Healthy virus free seed crop can be grown, which is very difficult under open field conditions.
• Seed production practices like training, pruning and hand pollination are easily manageable compared with
to field seed crop.

31. • Protected conditions provide the best opportunity for organic seed production in vegetables.
• More number of seed crops could be grown under protected conditions.
• By using soil less media, seed crops can also be grown even under saline and acidic soil conditions.
• Judicious use of water is possible for seed production under protected conditions.
• Grafting technology in seedling could be easily applied to overcome soil borne problems in solanaceous and
cucurbitaceous vegetables.
• Quality seed production of vegetables could be under taken by agri-entrepreneurs; this in turn could generate
employment opportunities in rural areas.
• No need to emasculate female parents because there are no insect pollinators.
• Seed production cost of vegetables could be reduced under protected conditions.
• Seed crops not damaged by un-seasonal rains at the time of their maturity unlike open field seed crops.
• Off type plants, objectionable weeds or plants affected by designated diseases cannot pose problems in the seed
crops raised under protected conditions
• Seed viability and seed vigor could be extended through better nutrient management in seed crops under
protected conditions.

32. Constraints
• Lack of awareness among farmers pertaining to potentials of protected vegetable seed
production.
• Lack of major research programme on protected vegetable seed production.

33. Case studies

34. • The present investigation was carried out under insect proof net house (IPN) and open field
condition (OFC) at Centre for Protected Cultivation Technology and Seed Testing Laboratory,
IARI, New Delhi.
• Hybrid seed production under north Indian condition cannot be organized successfully in open
field condition because of high incidence of viral diseases and white fly attack in kharif season.
• Besides this, in spring summer the plant growth and development are greatly affected by
changing environmental conditions, early onset of high temperature, unseasonal rains during
summer (April-June), sudden increase in temperature hamper the production of female flower,
fruit set and fruit development, resulting in low seed yield and seed quality.

35. Jat et al (2016)

36. Jat et al (2016)

37. • The present investigation was carried out during kharif 2013-14 at Centre for Protected Cultivation
Technology, Indian Agricultural Research Institute, New Delhi
• under two different growing environments, i.e insect proof net house and open field condition.
• The hybrid selected for the experiment was Pant Shankar Khira-1.

41. Economics of hybrid seed production
• The cost to benefit ratio worked out for all three conditions revealed
• the insect proof net house was more profitable (1:2.25) followed by
• open condition (1:1.12) and
• naturally ventilated polyhouse is uneconomical (1:0.37) because of more initial
investment.

42. • The high incidence of red pumpkin beetle in early growth period, fruit fly at fruit development stage and
fruit rot during maturation period are the major challenges in organizing successful seed production
programme of parental line.
• The sharp rise in temperature during fruit development in May greatly influence the fruit set, fruit
development, seed yield and quality produce.
• Hence, the present investigation were planned and carried out to explore the possibility of growing of
parental lines for quality seed production of Pusa Hybrid-1 under insect proof net house and open field
during summer season (15th Feb to June) of the year 2008 at Centre for Protected Cultivation
Technology (CPCT).

45. Conclusion
• Protected cultivation provides many fold advantages over open field seed production of
vegetables.
• The beauty of vegetable hybrid seed production under protected conditions is that it
could be implemented at a micro or macro level depending upon the need, space and
seed crop requirements
• This technology is highly productive, amenable to automation, conserves water,
fertilizer and land, and provides the required environment to overcome the biotic and
abiotic stress and enhance yield as well as the quality of seeds.
• Protected cultivation offers very congenial environment for producing healthy, virus
free, and genetically pure hybrid seed with higher seed yield per unit area.

46. Thank You