Development and application of a SRAP marker for the identification of sex in Buchloe dactyloides

Buffalograss, Buchloe dactyloides (Nutt.) Engelm, is a dioecious turfgrass native to the Great Plains of North America. Since its naturalization, it has become the most wildly cultivated warm-season turfgrass in northern China. While dioecious plants represent only a small proportion of all plant species, they are important models in the study of plant sex determination and evolution. The identification of the sexes is important in the theory and practice of breeding programs. At present, there is no effective method to determine the sex of early stage buffalograss. The objective of this study was to use sequence-related amplified polymorphism (SRAP) and integrated bulked segregant analysis (BSA) technology to find sex linked markers in B. dactyloides. A total of 228 primer combinations were screened and 2,690 SRAP bands examined. Only ME9/EM2 could generate a specific fragment (~240 bp) in all the female plants, which was absent in male plants. The methods described here provide a simple and reproducible means of early sex identification in B. dactyloides.