大豆吸胀前后籽粒外形指标的变化

Changes of Seed Shape Traits in Pre- and Post-Imbibiton Soybean (Glycine max (L.) Merri.)

摘要: 大豆是全球最重要的粮油作物之一，探讨大豆籽粒吸胀前后的外形变化对于揭示不同品种的籽粒吸胀特性、播种墒情选择和品种利用具有重要意义。研究利用41个大豆品种(系)做试材，测定种子吸胀前后籽粒重量、粒体积(按排水量计)、粒长、粒宽和粒厚变化，进行相关分析、逐步回归分析和聚类分析。试验结果显示：1) 吸胀前后试验材料间籽粒特性差异明显，其中吸胀前后粒体积的变异系数最高，粒长和粒厚变异系数较小，而粒宽变异系数增加明显。2) 大豆籽粒吸胀前后所有籽粒性状(粒重、粒体积、粒长、粒宽和粒厚)间的简单相关系数都达到极显著水平。偏相关分析显示，只有粒重与其他籽粒性状的偏相关系数都表现显著正相关，偏相关系数大小顺序为粒长 > 粒厚 > 粒宽；而粒体积与粒长、粒宽和粒厚的偏相关不显著；粒厚与粒宽的偏相关系数基本保持稳定(低负相关)。粒长与粒宽和粒厚的偏相关性在籽粒吸胀前后存在差异：吸胀前粒长与粒宽显著而与粒厚不显著，籽粒吸胀后恰好相反。不同材料吸胀前后籽粒性状比及其相关系数也反映了同样的趋势。3) 大豆吸胀后粒重平均增加2.03倍，粒体积增加2.37倍，粒长增加1.71倍，粒宽和粒厚1.15倍。籽粒长宽厚比值由吸胀前的1.34:1.16:1变为1.98:1.16:1。4) 吸胀前后的粒重都可以用粒体积进行线性模拟。吸胀前的大豆粒重和粒体积也可用粒宽进行线性模拟，而吸胀后大豆粒重和粒体积可用粒长进行线性模拟，并且籽粒吸胀前的模拟效果要优于吸胀后的。5) 根据籽粒吸胀前后的粒形变化，将41个大豆材料Cluster聚类为9个小类。综合来看，大豆吸胀前后籽粒外形指标存在明显差异，外形指标中粒长的变化尤其明显，粒宽和粒厚的相对变化很小。粒重与粒体积相关性最大，粒重和粒体积的模拟在籽粒吸胀前后所选的籽粒外形指标不同。研究得出的结论将为籽粒性状的后续研究提供一定参考依据。

Abstract:  Soybean (Glycine max (L.) Merri.) is one of main food and oil crops. The exploration of seed shape traits changes during seed imbibition process is meaningful to elucidate the characteristics of seed imbibition, determination of soil water content and utilization of soybean varieties. Forty-one soybean varieties (lines) were served as materials and data of seed weight, seed volume measured in displacement water volume; seed width and seed thickness were collected in pre- and post-imbibition treatment and conducted correlation, stepwise regression, and cluster analysis. The results showed that: 1) The significant differences of seed traits were detected before and after imbibiton, with the highest coefficients of variance (CV) in seed volume, and lower CV in seed length and seed thickness, and CV increased evidently in seed width. 2) The Pearson correlation coefficients between all tested seed traits reached significant sense at 0.01 level. The partial correlation analysis indicated that only seed weight had positive correlation with other seed traits, listed as seed length, seed thickness and seed width in the descending order; seed volume had no relation with seed length, seed width and seed thickness; the relationship between seed thickness and seed width kept stable (lower negative correlation). The seed length showed different correlation pattern with seed width and seed thickness before and after imbibition. Before seed imbibition, seed length had significant correlation with seed width instead of seed thickness, however, after seed imbibition, seed length had significant correlation with seed thickness instead of seed width. The ratios of different seed traits in pre- and post-imbibition and their correlation coefficients exhibited the similar tendency. 3) After imbibition, there was 2.03 times increase in average for seed weight, 2.37 times for seed volume, 1.71 times for seed length, and 1.15 times for seed width and seed thickness. The ratio of seed length, width and thickness changed from 1.34:1.16:1 to 1.98:1.16:1. 4) Seed weight in pre- and post-imbibition could be stimulated by a linear function of seed volume. Seed weight and seed volume in pre-imbibition could also stimulated by a linear function of seed width, and seed weight and seed volume in post-imbibition could also stimulated by a linear function of seed length, and the stimulation efficiency in the former was better than in the latter. 5) Forty-one materials were clustered into nine groups based on the measured seed traits. To sum up, seed shape traits in pre- and post-imbibition had significant difference, and there was evident change in seed length, and less changes in seed width and thickness; high correlation between seed weight and seed volume was detected, and selection of seed shape traits was different in pre- and post-imbibition for seed weight and seed volume. These results can be referred in the subsequent study on seed traits.