. What are Post pollination development of pollen grain and what are the stages


Best Answer

It occurs in following stages:

1.Absorption of water and nutrients by pollen grain from stigmatic secretion through its germ pores.

2.Enlargement of tube or vegetative cells.

3,Tube comes out of the pollen grain, through one of the germ pores or germinal furrows to form a pollen tube.  Pollen tube remains covered by intine layer.

4.Secretion of pectinase and other hydrolytic enzyme occurs, from pollen tube, which help it to create a passage in the style.  

5.For the growth of pollen tube nourishment is absorbed from style.

6.Now the tube nucleus descends to the tip of the pollen tube.

7.The generative cell which also passes into pollen tube, soon pides into two males gametes if it is not already pided.  

8.Male gamete has large nucleus, which remains surrounded by a thin sheath of cytoplasm.  Later on tube nucleus degenerate completely.

Thus pollen tube contains

i) Dense cytoplasm towards tip ii) Two male gamates

iii) Degenerated tube nucleus iv) Vacuolated cytoplasm behind the tip.

 

Talk to Our counsellor