玉米籽粒大小是籽粒产量的重要构成因素之一，而目前对不同玉米种质籽粒大小和形状的综合分析还很少，关于籽粒大小和形状与籽粒营养间的关系的知识甚少。本研究使用包含丰富遗传变异的508份玉米自交系对玉米籽粒大小和形状等8个性状进行考察，分析其在不同遗传材料间的分布差异，基于该群体建立了籽粒大小的分类指标，研究了籽粒大小和形状与籽粒营养间的相关。籽粒大小和形状等8个性状的平均变异系数（CV）为10.8%，其中粒长的变异（CV = 9.4%）大于粒厚（CV = 8.7%）和粒宽（CV = 7.6%）。粒厚和粒宽呈高度正相关（r = 0.44, P < 2.20 × 10?16），而粒厚和粒长呈较强负相关（r = ?0.30, P = 5.79 × 10?11），同时粒长和粒宽相关不显著（r = ?0.06, P = 1.81 × 10?1），暗示籽粒在长度维度的变异更具特异性，这与主成分分析中粒长在PC1维度和其它性状分开的观察相一致。籽粒整体大小（如粒体积和百粒重）在不同类群中的变异较小，而粒长、粒厚、粒宽长比等形状性状在不同类群中差异显著，其中坚秆综合群材料的籽粒偏长、偏薄，而热带/亚热带及非坚秆综合群材料的籽粒偏宽，偏厚。508份自交系被分为特大粒（8份）、大粒（75份）、中粒（345份）、小粒（72份）和特小粒（8份）五个类别，其中在8份特大粒材料中鉴定到优良自交系吉846、郑58、综3、C8605。籽粒大小和形状等8个性状和籽粒营养的相关性都较弱，且大部分为负相关，表明籽粒大小和形状不是决定籽粒营养的主要因素。本研究结果将为玉米籽粒产量和品质改良提供重要信息。

Maize kernel size is one of the important components of grain yield. At present, there are few comprehensive studies on maize kernel size and shape using different maize germplasm, and there is little knowledge about the relationship between kernel size and shape and grain nutrition. This study used 508 inbred lines to investigate 8 kernel size and shape traits and compared their distributions among different maize germplasms. Further, the classification indicator of kernel size was established, and the relationship between kernel size and grain nutrition was investigated. The average coefficient of variation (CV) of 8 traits was 10.8%, and the CV of kernel length (9.4%) was greater than kernel thickness (8.7%) and kernel width (7.6%). The kernel thickness and width were highly positively correlated (r = 0.44, P < 2.20 × 10?16), while kernel thickness and length were negatively correlated (r = ?0.30, P = 5.79 × 10?11), and the correlation between kernel length and width was not significant (r = ?0.06, P = 1.81 × 10?1), suggesting that the variation of the kernel in the length dimension is more specific, which was consistent with the observation that the kernel length was separated from other traits in the PC1 dimension in principal component analysis. The overall kernel size (such as kernel volume and kernel weight) varied little between materials from different germplasms, while the kernel length, kernel thickness, kernel width-to-length ratio showed significant differences. The 508 inbred lines were divided into 5 categories: extra-large (8), large (75), medium (345), small (72), and extra-small (8). It is worth noting that elite inbred lines JI846, ZHENG58, ZONG3, and C8605 were identified in the extra-large group. The correlation between 8 kernel size and shape traits and grain nutrition is weak, and most of them are negatively correlated, indicating that kernel size and shape are not the main factors that determine grain nutrition. The results of this study will provide important information for future maize grain yield and nutrition improvement.

创新研究群体科学基金