| Based on the seventeen traits data of 870 foxtail millet resources collected by investigation, the resources were divided into 7 groups based on their botanical variety, The key accessions were established based on the analysis of 17 phenotypic traits by the square root strategy, UPGMA clustering within groups and random sampling in individual clusters, and evaluated by t-test, F-test, Chi-squared test, the ratio of phenotypic retention analyses. Finally, the principal components analysis and the histogram analysis were used to re-confirm the foxtail millet key germplasm. The total of 85 as a key germplasm was selected, accounting for 9.8% of total resources, which included 21 white varieties, 49 yellow varieties, 3 orange varieties, 5 cyan varieties, 4 red varieties, 2 black varieties, 1 brown varieties. The results of significant analysis showed that the variance, coefficient of variation, and Shannon-weaver diversity index for 17 phenotypic traits were not significantly different between key germplasm and entire collection(P＞0.05), and the distribution range, the ratio of phenotypic retention of all resources were preserved, the phenotypic correlations displayed the same genetic association and distribution frequency between two collections. Thus, this key germplasm can represent the genetic variability and population structure of entire collection, reduce the genetic population in all resources, and can be provided a theoretical basis in evaluation of foxtail millet and cultivation of new varieties. |