基于表型性状的薏苡初级核心种质库构建

本研究以收集的248份薏苡种质资源为基础,按地理来源将标准化的14表型数据分组,采用最短距离逐步取样法并按一定比例抽样,共获得8个候选核心子集,利用变异系数变化率、均值差异百分率、极差符合率、方差差异百分率、表型保留比例、表型频率方差和Shannon-Wiener指数7个参数进行核心种质代表性检验和评价。结果表明：薏苡初级核心种质库包含67份资源,保留了原始种质27.02%的样品（25%组内取样比例）,其变异系数变化率、均值差异百分率、极差符合率、方差差异百分率、表型保留比例、表型频率方差和Shannon-Wiener指数的检验指标分别为110.05%、0、93.03%、10%、96%、0.655和0.881;t测验结果表明,核心种质库14个表型性状均值与原始种质无显著性差异,仅有3个表型的某一性状级别丢失,其余11个表型均保留了原始种质的所有性状级别（RPR=1.0）,保留表型性状级别比例为96.49%,且多数表型性状的变异系数和遗传多样性指数均略高于原始种质。其结果说明,获得的核心种质库代表性好,遗传多样性丰富。该结果为后期薏苡种质资源的收集、保护、创新利用奠定了重要基础。

Establishment of Coix lacryma-jobi L. Core Germplasm Collection Based on Phenotypic Characters

A total of 248 accessions of Coix lacryma-jobi L. were grouped by geographical source and least distance stepwise sampling based on 14 phenotypic data. Eight candidate core collections were obtained according to a certain sampling proportion. The candidate core collections were then evaluated by the variable rate of coefficient of variation, mean difference percentage, coincidence rate of range, variance difference percentage, ratio of phenotypic retained, variance of phenotypic frequency and Shannon-Wiener diversity index. The primary core collections of C. lacryma-jobi L. contained 67 accessions with 27.02% of the original germplasm resources retained (25% sampling ratio within the group). The variable rate of coefficient of variation, mean difference percentage, coincidence rate of range, variance difference percentage, ratio of phenotypic retained, variance of phenotypic frequency and Shannon-Wiener diversity index was 110.05%, 0, 93.03%, 10%, 96%, 0.655, 0.881, respectively. Results of t-test showed that no significant difference was found in the mean of 14 phenotypic data between the primary core collections and original collections, with only three phenotypic traits lost some trait levels, 11 phenotypic traits retained all trait levels of the original collection (RPR=1.0), and the proportion of retained phenotypic data levels was 96.49%. The variation coefficient (CV) and Shannon-Wiener diversity index (I) of most traits were slightly higher than those of the original collection. It indicated that the core collection was of more representative and richer genetic diversity. The results laid an important foundation for the collection, protection and innovation of C. lacryma-jobi L. germplasm resources.