Pollen allelopathy: Past achievements and future approach

Transfer of pollens from one plant species to another leads to harmful or beneficial effects on the target species. Such interactions result into pollen allelopathy. Allelochemicals released from the pollens of allelopathic species interfere with pollen germination or tube growth, stigma or style receptivity, ovule development, seedling germination and growth, leaf chlorophyll content, fruit set and seed set. Earlier allelopathy was mainly confined to the effects of the chemicals exuded from the roots, leaves, stem and other vegetative parts. However, recent studies on allelopathy include pollen grains, which influences their fertilization and reproduction in the target species in both ways. Here we reviewed the recent work done on pollen allelopathy.