Abstract:
Rice (Oryza sativa L.) varieties cultivated widely in Thailand were developed to be suitable for agriculture and trading. They are at risk for inbreeding depression scenario due to frequent breeding of close relative cultivars. Finding of new genetic stock become an important process for future rice breeding. This research aimed to reveal genetic diversity and evolutionary relationship among 20 highland rice landraces in northern Thailand and 5 commercial varieties. Fragment analysis of 28 highly variable simple sequence repeat (HvSSR) markers using realtime PCR technique together with genetic distance analysis had reveals that studied rice varieties could be separated into 2 groups. The first group consisted of 9 highland landraces i.e. Buephopri, Lueang Lisu, Buephobo, Buepamae, Bueso, Blela, Buemue Maela, Buechepre Maeridpakae, Buepololekha , which clustered with 5 commercial rice of Thailand. The other 11 landraces i.e. Chanonue, Khao Musser, Chanomeoi, Chabebe, Buephato Nongkhiaw, Buetola Nongkhiaw, Buetolaso Sobkhong, Bueikae Sobkhong, Chatepui Huaylannai, Chachikui Huaylannai, Deang Musser formed the second group. This second group exhibited significant different genetic structure (p<0.05) from the first one and could be selected as a new genetic resource for further rice development and breeding.