No abstract

In this study, variability of rice landraces in Ratchaburi, Thailand was investigated using seed morphology and DNA sequences. This information is useful for understanding the extent of diverse level of rice landraces in order to provide desirable characters for accomplishing the efficient rice improvement and conservation program. Collected 9 rice landraces were observed using qualitative (awn presence, awn color, lemma and palea color, lemma and palea pubescence, sterile lemma color, sterile lemma length, and seed coat color) and quantitative (1000-grain weight, grain length with and without husk, grain width with and without husk, and ratio length/width with and without husk) characters. Using cluster analysis, all traits divided these rice landraces into two major clusters. Moreover, these rice landraces were also analyzed using single nucleotide polymorphism data based on two putative neutral fragments. This study presented low level of nucleotide diversity for all populations. The statistical tests of neutrality indicated significantly positive departure from neutral equilibrium, which suggested the high intermediate-frequency polymorphisms in these rice landraces. 