Abstract
The pollen-pistil interaction comprises a diverse set of simultaneous and interacting processes between the male gametophyte (pollen) and the female reproductive organ (pistil). Determining the molecular basis of the cross-talk that occurs between pollen and pistil tissues during pollination is vital, because the world's population depends on the biological process of plant fertilization for food, both directly (cereal crops) and indirectly (the consumption of animals fed on fodder crops). Recently, several advances have been made to identify molecules that mediate specific events during the pollen-pistil interaction. However, despite the identification of an increasing number of molecules implicated in pollen-pistil interactions there are few examples of conserved genes between species, suggesting that different taxa have employed alternative molecular mechanisms for achieving successful reproduction, as has been illustrated by the diverse range of self-incompatibility (SI) mechanisms identified to date.