Population Characteristics And Genetic Diversity Analysis Of Oryza Granulata In Yunnan Province

Field survey on Oryza guanlata resources at present was carried out in Yunnan Province. The investigated areas covered six cities or prefectrues, which were Yuxi City (Xinping County),Puer City(Simao Distinct and Yunxian Township), Xishuangbanna Prefectures(Menghan County), Baoshan City(Longling County and Shidian County), Lincang Prefectures (Zhenkang County and Gengma Town), and Dehong Prefectures (Yingjiang County). This paper has conducted intensive demography investigation on17populations. At the same time,,13populations whose size was more than20individuals were sampled for genetic diversity study by inter-simple sequence repeat (ISSR) marker analysis. The main results were as follows:1.In the17populations, there were12populations had more than100individuals, accounting for70.59%of the total. Two populations only had less than5individuals, which were in the demise of state. Three populations had more than200individuals. There were14populations under human disturbance, accounting for82.35%, of which,12populations are under moderate disturbance. Populations were formerly recorded having a larger number of individuals suffered serious damage, even on the brink of extinction. Kruskal-wallis correlation test showed that the population size and distrubance degree had significant relationship.The field investigation found a new population in Yunxian country.2. The genet density of Oryza guanlata population ranged between1.40-9.57individuals/m2, and the tiller density of population ranged between11.70-45.20tillers/m2. There were significant difference among the regional populations.3. Oryza granulata has strong ability of asexual reproduction. Tiller number per genet ranged between1to20, and the average was6. Oryza granulata also had high seed setting rate, each row had3to20grains, the average was8.53. The seed production was distinctive among the regional populations.4.108bands were ditected by10ISSR primers in13populations, which93were polymorphic. The percentage of polymorphic bands was89.81%. The lengths of amplified bands ranged from100bp to2500bp. The mean Nei’s gene diversity (h) was0.3510and the mean Shannon information index (I) was0.5159. PPB of different populations were 62.96%to83.33%.The genetic identity among O. granulata populations were0.73041to0.9631, genetic distance were0.0376to0.3142.Facing with the dangerousness of habitat lose, we should put much effort to protect the Oryza guanlata populations in Yunnan Province.