DETECTION OF ABA AND PROLINE IN POLLEN

Immature, half differentiated, and fully mature pollen grains from various plants were analyzed for abscisic acid (ABA) and proline content. The ABA concentration was determined by High Performance Liquid Chromatography (HPLC) and Enzyme-Linked Immunosorbent Assay (ELISA). Proline was detected by a colorimetric test. In pollen, both trans trans (tt) - ABA and cis trans (ct) - ABA decreased in concentration from the immature to the fully mature stage. Fully mature pollen grains exhibited only trace amounts of tt-ABA. The ct-ABA levels of mature pollen from gymnosperms and anemogameous angiosperms were higher than those from entomogameous angiosperms. The proline concentrations of mature pollen showed strong fluctuations among the different species. A correlation between endogenous levels of ABA and proline was not found.