POLLEN-RELATED CHARACTERISTICS OF DIOSPYROS LINN. (EBENACEAE) ANDROECIOUS GERMPLASMS NEWLY FOUND IN CHINA

Several Diospyros spp. androecious germplasms were newly found in the Dabieshan Mountains, Hubei province, China. In order to identify the taxonomic position and evaluate the breeding value of these materials, their chromosome ploidy, the male flowers bearing capability, pollen number, pollen diameter, pollen germination percentage and pollen-stigma compatibility from six androecious types were investigated. Flow cytometry analysis showed that these androecious germplasms were hexaploid. Androecious types steadily bear male flowers in situ conservation and ex situ conservation, and the flowering period lasted 10-15 days. Mean pollen number per flower ranged from 110,000 to 222,000 and mean pollen number per anther ranged from 8,000 to 12,600. The pollen diameter of androecious germplasms was about 50 μm, similar with other hexaploid cultivars (2n=6x=90), and larger than diploid oily persimmon (D. oleifera Cheng., 2n=2x=30). The pollen germination percentage of androecious types ranged from 10 to 40%, which was less than that of ‘Zenjimaru’. Pollen tube growth normally in stigmas of ‘Maekawa-Jirou’ and ‘Mopanshi’ were examined with fluorescence microscopy, which indicated good pollen-stigma compatibility between Diospyros spp. androecious genotypes and two female parents. Thus, these androecious germplasms could be candidates for pollinations in fruit production and genetic improvement in persimmon.