Autoclaving of various carbohydrates resulted in decreased in vitro pollen germination and/or pollen tube growth in species belonging to different families. This toxicity was eliminated by treatment of autoclaved sucrose and glucose solutions with activated charcoal. Autoclaving-induced hydrolysis of sucrose at pH6 resulted in stimulated Agapanthus praecox pollen growth (in detoxified media) probably due to the formation of glucose which was found to be a superior carbohydrate source for in vitro pollen growth in this species. Considering these results as well as previous reports on anther culture studies, autoclaving-induced toxicity from and hydrolysis of carbohydrates should be taken into account in all pollen and anther culture studies as well as in vitro pollination of ovules