Abstract: Inter-simple sequence repeat (ISSR) molecular markers were used to detect the genetic diversity among 139 individuals from 8 populations of Chinese sumac aphid Schlechtendalia chinensis collected from Guizhou Province, China. 12 ISSR primers were evaluated for their ability to produce polymorphic bands, and these primers yielded a total of 133 scorable bands, averaged 11 bands each primer. There was no population-specific marker, which was present in one population but absent in the others. Popgene analysis indicated that 100% of these loci were polymorphic, even though the primers were not intentionally selected for high variability. The genetic similarity was 0.899-0.955, and the genetic distance was 0.046-0.106, indicating a lower genetic diversity of S. chinensis populations. Cluster analyses showed that the aphid populations were divided into 2 groups, and the genetic diversity had no evident correlation with geographic area but negatively correlated with the mean air temperature and rainfall in March.

Key words: Oryza sativa, Low P tolerance, Genotype, Screening index, Evaluation index