Development Of Core Collection And Assessment Of Genetic Diversity Of Oats (Avena Spp.)

Oats(Avena L.)is a kind of minor crop which has high values in nutrition, eating, health protection and feeding livestock. In this study, core collection was developed from 3255 accessions oat germplasm and then genetic diversity of core collection was assessed with both phenotypic and molecular tools.In core collection development, the whole collection was grouped first according to origin, then sub-grouped by hullness; number of samples in each sub-group was determined by square root, logarithmic, proportion methods, and finally individual samples were selected by clustering and random methods. A total of 13 core subsets were developed for comparing analysis on 7 parameters, namely coincidence, variance of phenotypic traits, genetic diversity index etc. The optimum samples for the core collection were identified and adjusted to 328 accessions according to range of quantitative traits, grades of qualitative traits and analysis of genetic diversity.In phenotypic analysis, the Shannon-weaver index of Shanxi naked oats was 1.067 which was the highest among all origins. Naked accessions from Qinhai were 0.478 which was the lowest. In the 22 characters, the Shannon-weaver index of lodging resistance was the highest, while panicle type was the lowest. Genetic similarity index of naked oats between Qinghai and Gansu-Ningxia was 0.576 which was the highest, and that between Shanxi and southwest of China was 0.259, which is the lowest. For hulled oats, the Shannon-weaver index of oversea origin was 0.979 which was the highest, while those from northeast of China was 0.403, which was the lowest. In the 22 characters hulled oats, the Shannon-weaver index of kernel weight per plant was the highest, while that of spikelet shape was the lowest. The genetic similarity index of hulled oats between Xinjiang and northeast of China was 0.618 which was the highest, while that between Xinjiang and southwest of China was 0.315 which was the lowest. Correlation analysis on 19 traits showed that correlation coefficient between spikelet shape and kernel shape was the highest; oat smut has a significant correlation with kernel shape; 1000-kernel weight and kernel weight per plant have significant correlation with kernel shape, spikelets of main panicle, length of main panicle; effective tiller number has significant negative correlation with the second leaf width and length; A useful genepool composed of 100 accessions with different elite traits such as high yielding, disease resistance, high quality.In SSR analysis, a total of 61 alleles were detected using 15 SSR markers, the number of alleles per locus ranged from 2 to 7, with average of 4.067. The mean of polymorphism information content(PIC)was 0.600. PIC of M83381 was 0.789 which was the highest, while that of Xgwm99 was 0344 which was the lowest. Shannon-weaver index of America accessions was 1.118 which was the highest, while that of Xinjiang was 0.459 which was the lowest. The genetic similarity coefficient between southwest of China and Shanxi was 0.517 which was the highest, while that between southwest and northeast was 0.373 which was the lowest.