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UNIT 1 SEED DEVELOPMENT PRODUCTION AND STORAGE
Seed development
A true seed is defined as a fertilized mature ovule consisting of embryo, stored food material andprotective
coats.. The important events involved in seed development and maturation include
Seed Formation:The seed formation takes place by the following steps:
1Gametogensis 2.Pollination 3.fertilization 4.Development of seed
Gametogensis: Formation of male and female gametes with haploid chromosome number for fertilization
is known as gametogensis. Gamate formation take places separately in male (anther) and female (Ovule)
part of the flower. It involves two steps i.e., sporogensis followed by gametogensis in both male and female
reproductive parts.
Sporogensis: Its the formation of spores in a reproductive part I.e, spores of male and of female Formation
of male gamates.Its has two steps microsporogensis and microgameteogensis. Androceium (stamen) is the
male part of the flower with anther and filament is its part.Anther has four chambered structure placed on
filament.Each chamber is known as pollen sac ( Microsporangia)
Microsporogensis: In the pollen sac,pollen grains are formed. Inner most layer of pollen sac in known
tapetum that provides nutrients for development of pollen mother cell(2n) in each pollen sac.The diploid
pollen mother cell under goes meiosis cell division,first form two dyad and then for haploid cell. Each one
is known as microspore.
