Studies On Genetic Diversity Of Haloxylon In Xinjiang With ISSR

Haloxylon persicum and Haloxylon ammodendron were xerophytic desert shrub. As dominate desert plant, they played important role in the maintenance of the structure and function of the Desert Ecosystem. During the last few decades, Irraiional exploitation had resulted in the destruction of Haloxylon persicum and Haloxylon ammodendron vegetation and development of mobile sand dunes. The genetic relationship and genetic diversity of Haloxylon persicum and Haloxylon ammodendron in Xinjiang of China were studied by ISSR molecular marker technique.1. The percentage of polymorphic was 84.85% in four populations of Haloxylon persicum with 11 ISSR primers. The percentage of polymorphic loci shared a range of 33.92%~40.35%; Shannon index was 0.3518 and Nei's index was 0.3482 of Haloxylon persicum; The genetic diversity based on Nei's method, among Haloxylon persicum populations was 0.1312. The coefficient of gene differentiation was 0.6183. The estimate of gene flow is 0.3016. The percentage of genetic identity of Haloxylon persicum was between 0.6221~0.7239,the smallest was Tulufan population and Wusu population.2. The percentage of polymorphic was 89.23% in eight populations of Haloxylon ammodendron with 11 ISSR primers. The percentage of polymorphic loci shared a range of 23.42%~45.05%. The highest was Wusu population. Shannon index was 0.3518 and Nei's index was 0.3482 of Haloxylon ammodendron. The genetic diversity based on Nei's method, among Haloxylon ammodendron populations was 0.1216. The coefficient of gene differentiation was 0.6378. The estimate of gene flow is 0.2840. and The percentage of genetic identity of Haloxylon ammodendron was between 0.6414~0.7942, and the smallest was Mosuowan population and Wusu population.There all have higher genetic diversity in Haloxylon persicum and Haloxylon ammodendron. based on Nei's genetic distance construct UPGMA tree between populations. Based on the results of the analysis, Haloxylon persicum and Haloxylon ammodendron populations have high genetic diversity. This imply that Haloxylon plants's rare was not restrainted by the deficiency of genetic diversity, but also by others factors. It is proposed that the habitats of Haloxylon persicum and Haloxylon ammodendron should be protected. Meanwhile.numbers can be increased by artificial propagation.