Agriculture

1. METHOD OF SEED PRODUCTION
FOR SELF POLLINATED AND CROSS
POLLINATED VEGETABLES
PGS-504
Submitted by:- Tapan Adhikari
Ph.D. Scholar, First Year
F-2019-15-D
Dept. Of Forest Product
Discipline: Medicinal & Aromatic
Plants
Submitted to:- Dr. Upender Singh

2. POLLINATION
Pollination: Pollination is the process by which pollen grains from an
anther, the male portion of a flower, are transferred to a female part in the
flower, known as the stigma.

3.  The goal of every living organism, including plants, is to create offspring
for the next generation.
 Seeds can only be produced when pollen is transferred between
flowers of the same species.

4. SELF POLLINATION/ AUTOGAMY:
In such pollination, pollen from an anther falls on the stigma of the same
flower.
CROSS-POLLINATION/ ALLOGAMY:
pollens from flowers of the plant are transmitted to the stigma of flowers of
the another plant by wind (anaemophily), water (hydrophily) or insect
(entomophily).

5. SELFPOLLINATION/AUTOGAMY:MECHANISM PROMOTING SELF POLLINATION:
 CLEISTOGAMY: In this, flower do not open at all i.e. complete closed
flower.
e.g. Wheat, oat, barley and some grasses.
 CHASMOGAMY: Flowers open only after pollination.

6.  In some crops stigma is closely surrounded by anthers and pollination
generally occurs when the flowers open.
e.g. Tomato, brinjal.
 In some species, the flowers open but the stamens and stigma are hidden by
the floral organs.
e.g. Pea, mung, urd, soybean, gram.
 In few species, the stigma becomes receptive and elongates through the
staminal columns.
self-pollination leads to rise in homozygosity

7. Self pollinated vegetables:
Tomato
Okra
Brinjal
Chillies
Potato

8. CROSS POLLINATION
MECHANISM PROMOTING SELF POLLINATION:
 DICLINY :
Dicliny is the name of condition where flowers are either staminate or
pistillate.
It is of two types:

9. a. Monoecy: Staminate & pistillate flowers are found in the same plant either
in the same inflorescence or in separate inflorescence.
e.g. Castor, mango, banana & cocnut.
b. Dioecy: Staminate & pistillate flowers are found on different plants.
e.g. Papaya, dates, hemp, asparagus, spinach.

10.  DICHOGAMY:
Maturity times of stamens and pistils of hermaphrodite flowers are
different.
a. Protogyny: Pistils mature earlier than stamens. e.g. Bajra.
b. Protogny: Stamens mature earlier than pistils. e.g. Maize, sugarbeet

11.  In some plants, stigma is covered with a waxy film which is broken by the
visit of honey bees facilitating cross pollination. e.g. Lucerne or alfalaf.
 More than one mechanism may occur in some species. e.g. Maize has both
monoecy or protandry.

12.  SELF INCOMPATIBILITY:
Self incompatibility means the failure of pollen from a flower to fertilize
the same flower or other flower on the same plant. Here male gamete is
fully functional.
e.g. Brassica sp., Nicotiana, Radish etc.

13. CLASSIFICATION OF SELF-INCOMPATIBILITY:
1) HETEROMORPHIC SYSTEM:
Flower of different incompatibility groups are different in morphology. The
compatibility reaction of pollen is dtermined by the genotype of the plant
producing them.
The incompatibility system is heteromorphic-sporophytic.

14. 2) HOMOMORPHIC SYSTEM:
Morphological differences between flowers is
not associated with incompatibility. The
incompatibility reaction of pollen is either
controlled by the genotype of the plant on
which it is produced (sporophytic control) or
by its own genotype (gametophytic control).

15. GAMETOPHYTIC SYSTEM:
The incompatibility reaction of pollen is determined by its own
genotype and not by the genotype of the plant on which it is produced.
e.g. Pineapple, ryegrass, coffee, cloves etc.

16. SPOROPHYTIC SYSTEM:
The incompatibility reaction of pollen is determined by the genotype
of the plant on which the pollen is produced and not by the genotype
of the pollen.

17.  MALE STERILITY:
Male sterility means the non-functional pollen grains. Here, female gamete
is fully functional. Male sterility is not common in natural population.
It is classified into four groups:
 Genetic male sterility (GMS)
 Cytoplasmic male sterility (CMS)
 Cytoplasmic-genetic male sterility (CGMS)
 Chemically-induced male sterility

18.  Genetic male sterility (GMS):
Genetic male sterility is ordinarily governed by a single recessive gene ms
but also by dominant genes. Male sterility alleles are occurred
spontaneously or are induced artificially.
e.g. Rice, tomato, wheat etc.

19.  Cytoplasmic male sterility (CMS):
male sterility is governed by the cytoplasm. The male sterility is the result
of mutation in the mitochondiral genome (mt DNA) which leads
mitochondiral dysfunction.
e.g. Maize, bracissa.

20.  Cytoplasmic-genetic male sterility (CGMS):
The case of cytoplasmic male sterility where the nuclear gene for restoring
fertility in the male sterile line is known is called Cytoplasmic-genetic male
sterility.
The fertility restorer gene, R is dominant which restores male fertility in the
male sterile line.

21.  Chemical hybridising agent (CHA):
Chemicals which affect the function of male reproductive organs in plants
are called hybridising agents (CHAs) .
e.g. Maleic hydrazide (MH), Etherl (ethephon), Arsenicals, Mendok,
Hybrex (RH0007), Shell (WL 84811) etc.

22. Methods of seed
production
1. Seed - seed method (Certified seed production)
2. Head - seed method (Breeder seed production)

23. Seed to seed method
 The crop is allowed to over-winter
 Produces seed in their original position
 Where planted in the seedling stage
 The crop is rouged out. based on leaf colour , head shape
 Advantages:
 More seed yield but less quality
 Reduce cost of seed production

24. Head - seed method
 Matured plants after head formation are uprooted,
based on foliage and head characters
 The outer whorls of leaves are removed and,
 Immediately planted in well prepared main field
Advantages:
 Low seed yield but
 Higher quality seeds

25. Stump
method
Advantages:
 It gave extra income to farmers
 Crop matures 10-12 days earlier than head intact
method
 Seed yield slightly higher
Dis-advantages:
 Flowering shoots are decumbent
 Requires heavy staking

26. Stump with central core intact
metho
d
Advantages:
 Shoot is not decumbent
 Heavy staking not required
 Seed yield is slightly higher
Dis-advantages:
 Chopped heads cannot
be marketed

27. Head intact method
Advantages:
 Chopping of head on all sides not required
 Save time and labour cost
 Heavy staking is not required
Dis-advantages:
 Lower seed yield as compared to
other methods

28. Carro
t
 Is a biennial crop for seed production
 It requires chilling temperature of 4.8 -10°C for 40-
60 days to initiate flowering
 Very high inbreeding depression on selfing
 Highly cross pollinated crop, because protandrous
nature of flower

29. Contd…
 Pollen viable for 3-4 days before stigma receptivity
 Isolation distance 1000m
 Male sterility is also noticed in carrot
 Seeds produced only in hilly areas of HP, J&K
 High labor cost for emasculation and pollination
 Incidence of pest and diseases

30. Seed - seed
method
 The annual carrot crop is sown during Sept - Oct in the
plains
 Temperate carrot sown during Aug. - Sept. in the hills
 The crop is allowed to grow and produce seeds in
their original position
 Vigorous roguing should be practiced

31. Root - seed
method
 When the roots are fully matured the crop is harvested
 True to type roots are selected for next planting
 Tocut 1/4th of root and 1/3rd oftop
 Toobtain higher yield and quality seeds
 Harvested roots are carefully rogued out for colour and
over sized roots were discarded

32. Contd…
 Selected roots are replanted with a spacing of 60cm ×
30cm in well prepared field
 Fertilizer should be applied 50kg nitrogen and potash
 Irrigation is given immediately after planting
 Subsequent roguing for off-types and other weeds
 At full bloom stage

33. Contd…
 Early and late bolters are to be removed
Advantages:
 Low seed yield but
 high quality seeds

34. Radis
h
 Is a biennial crop for seed production
 It requires chilling temperature of 4-8 °C for 40-60
days to initiate flowering
 It is highly cross pollinated crop, because
protogynous nature of flower
 Stigma receptive 2-3 days before anthesis

35. Contd…
Isolation distance 1000m
 Temperature above 32°C results in dry stigma
 Pollens might fails to germinate

36. Seed - seed
method
 Crop is sown during October in the plains
 And in the hills during mid Sept. – Oct.
 The crop is allowed to grow and
produce seeds in their original position
 Vigorous roguing should be practiced

37. Root - seed
method
 When the roots are fully matured the crop is harvested
 True to type roots are selected for replanting
 Tocut 1/4th of root and 1/3rd oftop
 Toobtain higher yield and quality seeds
 Harvested roots are carefully rogued out
 Based on colour and over sized roots are discarded

38. Contd
…
 The selected roots are replanted at a spacing of 60cm
x 30cm for Asiatic varieties
 Fertilizer were applied with N 80 kg/ha and K 15kg/ha
 Irrigate the field immediately after planting of carrot

39. Potato
 Is a biennial crop for seed production
 Do not flower under short day condition
 Flowers were comparatively less at low temperature
 Self incompatibility is also noticed in potato
 Requires extra light of 4 hours during winter for flower
production in the plains

40. Contd…
 Male sterility with few viable pollens for pollination
 High labour requirement for emasculation and pollination
 Less number of seeds per fruit
 Is a self pollinated crop, but Some degree of cross
pollination due to protruded stigma
 Higher aphid infestation on seed crop

41. Pollination in potato
Emasculation and pollination in potato

42. True Potato Seed
(TPS)
True potato seed: means matured ovule developed in
potato as a result of sexual reproduction
Advantages:
 Requires 100-150g seeds/ha
 Traditional method with 2.5-3t/ha of seed tuber
 Low cost of planting material
 Easy transportation and no need of cold storage of seeds

43. Contd…
 Reduce the spread of diseases from one place to other
places
 Uniform germination of seeds
 Uniformity in the maturation of crop
 Seed tuber of 2.5-3 t/ha is used for human consumption
 High yield than crop grown from seed tuber

44. Onion
 Is a biennial crop for seed production
 Highly cross pollinated crop, due to protandry
 Do not produce flowers under short day conditions
 Isolation distance 1000m for foundation seed
 And for certified seeds 400m
 Roguing is done based on foliage colour, size of bulb and
colour of bulb

45. Seed - seed
method
 The first season bulb crop is left over winter in the field
 Toproduce seed in the following season
 The seed should not be used again for seed production.
Wide variation in bulb size
 Roguing can not be practice in this method

46. Advantages
 Higher seed yield
 Production of seed
 Less cost of seed production due to,
 Eliminating of expenses for bulb harvesting and storage

47. Bulb - seed
method
 Rabi season harvested bulbs were selected and stored till
Oct. – Nov.
 Storage temp. ranged from 4.5-14 °C for 4-6 months
 Bulb selected for replanting should be free from diseases
 Double and long thick neck bulbs are discarded
 Select true to type bulbs for planting

48. Contd…
 Select medium size bulb of 4-5 cm diameter with 40g
weight
 The 1/3rd portion of bulb is cut for easy and quick
sprouting
 Bulb should be disc like stem and root intact
 Roguing is done based on foliage, bulb shape and neck
characters