Abstract:

Three Quercus mongolica populations located at Jiayin, Xiaoxing′anling Mountain in Heilongjiang Province, Daqinggou in Inner Mongolia Autonomous Region, and Wulingshan in Hebei Province, and one Q. liaotungensis (a variety of Q. mongolica) population at Donglingshan in Beijing, totally 96 individuals were selected and analyzed by amplifications using 4 pairs of AFLP primers screened, each primer pair produced 63～113 bands and 346 polymorphic bands were obtained.As for Q.mongolica at species level, the effective number of alleles per locus (Ae) was 1 220, the percentage of polymorphic band (P) was 96.8%, and the Nei gene diversity index (H) was 0 145, Shannon's information index (I) was 0 246. At population level, the estimates were Ae=1.208,P=67.2%, and H=0.134,I=0 208 . In contrast, the estimates for Q.liaotungensis were almost the same (Ae=1.5,P =67.6%, H=0.134, I=0.220 ). As for Q.mongolica, genetic differentiation coefficient among populations (Gst) was 0.077. According to the UPGMA cluster analysis, the genetic distance among Q.mongolica populations became larger with the increase of geographical distance. The low level of genetic diversity of Q.mongolica might relate to the long term utilization as economic tree species in history, comparatively serious disturbance and environmental damage by human beings, and secondary forests of the existed stands.

Key words: Quercus mongolica, Quercus liaotungensis, Population, AFLP marker, Genetic diversity