Abstract:Anther wall browning in variety Taichung 65 of japonica rice （Oryza sativa L.） was studied through cold pretreatment of anthers at late uninucleate stage. Some microstructural and ultrastructural changes in the anther wall were found during anther culture. Anatomical observation showed that anther wall browning took place mainly in epidermis and endothecium. Cold pretreatment of anthers at 10℃ could effectively reduce the browning rate during the early culture period and delay degradation of the membrane structures of epidermis and endothecium, and thus postpone browning in anther wall. Meanwhile, cold pretreatment contributed to stimulating cell enlargement in the middle layer and delaying tapetum degradation, which produced positive effects on the microspore dedifferentiation. Although anther wall browning favored microspore in vigor and development, it was not the key factor in reducing the ability of pollen callus induction.
