ABSTRACT
Pollenkitt forms an oily, colorless to yellow-orange coating on pollen grains of angiosperms and is especially abundant in animal-pollinated species Several functions of pollenkitt are acknowledged. Especially insightful were speculations by F. Knoll, who, in addition to suggesting that pollenkitt pigments visually attracted flower visitors, also proposed that constituents of pollenkitt might provide nutrition and olfactory attractants to pollinators. Some relate to the survival of the male gametophyte, with pollenkitt providing protection against damage by ultraviolet light, excessive moisture loss, and microbial attack. Pollenkitt may facilitate pollinator service by providing visual attraction, olfactory attraction, and nutrition, as well as by increasing pollen adhesion. pollenkitt may play an important part in pollen-pistil interactions that are prerequisites for fertilization. Close examination will provide insight into the evolutionary pressures underlying the differential occurrences and diverse properties of pollenkitt within and among plant species.
