HORTICULTURE

Detailed explanation-1: -Once the pollen lands on the stigma, it forms a pollen tube. The pollen tube moves through the style and reaches the ovary. Once it reaches the ovule, the tip of the pollen tube bursts and releases the male gametes.

Detailed explanation-2: -After pollen germinates, the tube penetrates the stigmatic surface and grows into the transmitting tissue of the style. Mascarenhas and Machlis (1962) found a chemotropic response of pollen tubes to Ca2+ and observed a gradient of Ca2+ concentrations from the stigma to the ovule in the pistil of A. majus.

Detailed explanation-3: -Pollen Grains and Tubes☆ The pollen tube invades the pistil, growing between the walls of the stigmatic cells, then traveling through an extracellular matrix within the transmitting tissue of the style. The pollen tube finally arrives at the ovary, where it is attracted to an ovule that contains an egg cell.

Detailed explanation-4: -Pollen grains are transferred to the stigma via insects, birds, animals, wind or direct contact. Pollen hydration, germination and pollen tube growth through the pistil are the next steps. Within the pistil, chemical gradients produced by the female diploid tissue support pollen tube growth and guidance.