Influence of fatty acids on Petunia pollen grains

Fatty acids seem to be strong inhibitors of pollen germination in vitro, especially those with a carbon chain of 10 to 12 atoms. With at least one of these acids, namely 10-hydroxy-2-decenoic acid, this property is of practical importance. It prevents the germination of pollen stored by honeybees in their combs. This particular acid is added by the collecting workerbees from the mandibular glands. 10-OH-2decenoicacidinhibitstherespirationof pollen in culture solution, which could be the result of the blockage of one or more enzymes active in pollen-metabolism. In situ on the stigma, however, no inhibition of the germination occurs, probably on account of esterification with glycerides present in the stigma exudate.