关键词: 高粱, 种质资源, 穗部, 精准鉴定,遗传多样性, 综合评价

Abstract:

【Objective】 Through the research on the phenotypic diversity and genetic variation of the sorghum germplasm resources in the panicle, we will screen for superior sorghum germplasm, enrich the genetic information of sorghum panicle-related traits, and provide a reference for the conservation and efficient use of existing germplasm resources and the selection and breeding of new varieties.【Method】 Using 320 sorghum accessions from different parts of China as test materials, we accurately identified 12 panicle traits (grain length, grain width, thousand-grain weight, grain hardness, grain density, corneous endosperm rate, kernel weight per panicle, main panicle length, panicle neck length, panicle neck diameter, primary branches length, primary branches number) in two different ecological environments. A comprehensive evaluation of sorghum germplasm resources using correlation analysis, principal component analysis, cluster analysis, and other methods. We screened elite sorghum germplasms with different outstanding characteristics according to the comprehensive evaluation value F and target traits. 【Result】 The frequency distribution of each quantitative trait showed a trend of high in the middle and low on both sides. The two-year frequency distribution and curve trend of grain hardness, kernel weight per panicle and grain density, and corneous endosperm rate were similar at the Baoding and Jinzhong test sites. Most of the traits only showed normal distribution in one year or a single location. Except for the main panicle length and number of primary branches, the other traits differed between the two test sites in the same year. The mean diversity index (H') distribution of the 12 panicle traits ranged from 1.72 to 2.11, among which the average diversity index of grain hardness was the highest, and the average diversity index of primary branches length was the lowest. The coefficients of variation of grain hardness, corneous endosperm rate, kernel weight per panicle, primary branches length, and the number of primary branches were all higher than 30.00%. The cumulative contribution rate of the extracted four principal components was 65.39%. Cluster analysis classified the 320 accessions into three groups, class I can be used as the germplasm for screening process (broom) sorghum; class II is suitable for selecting excellent germplasm for grain (brewing) sorghum; class III was the germplasm with poor panicle traits. We screen 29 superior germplasm with outstanding characteristics according to the comprehensive score value F and target traits. 【Conclusion】 The variability of sorghum germplasm resources in panicle traits was rich and diverse; the coefficient of variation of corneous endosperm rate and primary branches length was high; grain length, grain width, grain hardness, grain density, and kernel weight per panicle were significantly affected by environmental conditions. We screened 29 superior germplasm.

Key words: Sorghum bicolor (L.), germplasm resources, panicle, accurate identification, genetic diversity, comprehensive evaluation