Assessing genetic diversity and its changes of bread wheat in Qinghai Province, China, using agronomic traits and microsatellite markers

摘要

Little is known about the diversity of wheat in Qinghai Province, China. Agronomic traits and microsatellite markers were used to survey genetic diversity and its change with time in 66 wheat cultivars registered from 1957 to 2009 in Qinghai Province.The average values of plant height, ear length, spikelets per ear, effective spikelets per ear, effective tillers per plant, internode length under spike, kernels per spike, grain weight per ear, 1,000-grain weight, and distance of spike base to auricleof flag leaf were studied. The mean Shannon-Weaver diversity index (H') was 1.67 and increased with time. One hundred and eighty nine microsatellite markers also were used to examine genetic diversity at a molecular level which showed that the average number of alleles (Na), genetic diversity index (He), and allelic richness (Rs) were 3.69, 0.5, and 3.45, respectively, and also increased with time but did not lead to a significant differentiation among the decades. These results suggest that the modernwheat breeding practice did not cause a genetic reduction in Qinghai Province.