what is pollen pistil interaction? describe in detail
Pollen-pistil interaction is a sequence of events that occur from the time of pollen deposition over the stigma till the time of entry of pollen tube inside the ovule.
The process has checks at several places for the promotion or inhibition of pollen growth.
It is helpful to the plant breeders in manipulating pollen growth even in incompatible cases.
It is a safety measure to ensure that illegitimate crossings do not take place.
Compatibility and incompatibility of the pollen-pistil is determined by special proteins.
Compatible pollens absorb water and nutrients from the surface of stigma, germinate and produce pollen tube.
Pollen tube grows into the style whose growth and path is determined by specific chemicals.
Entry of Pollen tube into the Embryo sac
- The fully developed embryo sac consists of 3 antipodal cells, 2 synergids, 1 egg cell and 1 secondary nucleus.
- The pollen tube pierces through the nucellus and ultimately, penetrates the wall of the embryo sac.
- The tip of the pollen tube disintegrates and the 2 male gametes are liberated in the embryo sac.
- One or both the synergids which help in directing the pollen tube towards the egg disintegrates