Camellia taliensis is one of the most important wild tea plants in China, especially in Yunnan Province. In this study, we described the development of 15 microsatellite markers from the genome of C. taliensis using the protocol of fast isolation by AFLP of sequences containing repeats (FIASCO). Polymorphism of each locus was assessed in 24 samples collected from six wild populations of C. taliensis. The average allele number of the microsatellites was four per locus, ranging from 2 to 7. The observed and expected heterozygosities varied from 0.076 to 0.5833 and from 0.1560 to 0.6917, respectively. Crossspecies amplification in other three tea plants showed eleven of them holding promise for sister species. These polymorphic SSR markers would be useful tools for population genetics studies and assessing genetic variations to establish conservation strategy, molecular identification and molecular breeding on this tea plant and its allied species and varieties in section Thea genus Camellia.

Sex-biased genes offer insights into the evolution of sexual dimorphism. Sex-biased genes, especially those with male bias, show elevated evolutionary rates of protein sequences driving by positive selection and relaxed purifying selection in animals. Although rapid sequence evolution of sex-biased genes and evolutionary forces have been investigated in animals and brown algas, less is known about them in dioecious angiosperms. In this study, we separately compared the expression of sex-biased gene between female and male flower buds and between female and male mature flowers in dioecious Trichosanthes pilosa (Cucurbitaceae). In floral buds, sex-biased gene expression was pervasive, and had significantly different roles on sexual dimorphism such as physiology. We observed higher rates of sequence evolution for male-biased genes in floral buds compared to female-biased and unbiased genes. Male-biased genes under positive selection were mainly related to abiotic and biotic stress, suggesting that high evolutionary rates are driven by adaptive evolution. Additionally, relaxed purifying selection may contribute to accelerated evolution in male-biased genes generated by gene duplication. Our findings, for the first time in dioecious angiosperms, suggest evident rapid evolution of male-biased genes, advance our understanding of the patterns and forces driving the evolution of sexual dimorphism in dioecious plants.