DENDROLOGY

Detailed explanation-1: -Pollination refers to the landing and subsequent germination of the pollen on the stigma. Hence it involves an interaction between the gametophytic generation of the male (the pollen) and the sporophytic generation of the female (the stigmatic surface of the carpel).

Detailed explanation-2: -The stigma is a specially adapted portion of the pistil modified for the reception of pollen. It may be feathery and branched or elongated, as in such wind-pollinated flowers as those of the grasses, or it may be compact and have a sticky surface.

Detailed explanation-3: -Pollen lands on the stigma, where it hydrates, germinates, and extends a tube that enters the transmitting tract (TT). The tube emerges onto the septum (S), grows up the funiculus (f), and enters the micropyle opening of the ovule (O), where it fertilizes the egg and central cell.