[RAPD and SCAR molecular markers linked to the sexuality of cycads (Cycas tanqingii D. Y. Wang)].

The random amplified polymorphic DNA (RAPD) technique was used to amplify DNA fragment, aiming at finding markers linked to the sex trait in Cycas tanqingii D. Y. Wang. A total number of 160 random primers were screened in the RAPD-PCR and more than 2500 RAPD fragments were generated from the male or the female plants. One fragment of about 500 bp was amplified steadily and repeatedly by the S0465 (CCCCGGTAAC) primer only from female plants but not male plants. The RAPD marker was then converted into female-linked dominant SCAR (Sequence Characterized Amplified Regions) marker named STQC-S465-483. The development of this sex-linked SCAR marker provides a possibility of identifying the sex of Cycas tanqingii before sexual maturation, which is very important to in situ or ex situ conservation.