Fertilization in plants is not directly influenced by sunlight. It occurs when pollen grains are transported from anthers to stigma. When ripe pollen from an anther catches on the stigma of the same kind of flower, each pollen grain sends out a small thread-like tube. Fertilization occurs after pollination, when pollen grains land on the stigma of a flower of the same species. During this time, a series of events take place leading to the formation of seeds.