麻楝种子形态和营养特征遗传变异分析

为系统揭示麻楝种源间种子形态和营养成分的变异程度和变异规律,以8个国家26个种源麻楝种子为试验材料,对不同种源麻楝种子的形态特征和营养成分进行比较分析。多重比较结果表明,麻楝种源间种子的长、宽、厚、长宽比、百粒重以及可溶性蛋白质、可溶性糖和淀粉含量差异极显著;相关分析表明,种子百粒重与种子长、种子宽呈极显著正相关,可溶性蛋白质、可溶性糖和淀粉含量与百粒重均呈极显著正相关;主成分分析结果显示,影响麻楝种子品质的第1主成分主要是种子形态性状,即种子长、百粒重和种子宽,第2主成分是种子营养成分;通过分析麻楝种子形态特征及营养成分变异系数可知,麻楝种子形态变异系数大于营养成分变异系数,表明种子形态受外界环境影响较大。通过主成分聚类分析,将26个种源分为2个集群,第1集群包括澳大利亚和马来西亚2个种源,其特点是种子形态较大、百粒较重、养分含量较高;第2集群包括其余24个种源。结合聚类分析和种子形态与地理气候因子相关分析结果可知,麻楝种子形态变异具有一定的地理区域特征,与分布区的自然地理因素有一定的相关性,麻楝分布区南部种子较大而北部种子较小。

Variation and Cluster Analysis of Morphological Characters and Nutrient Content of Chucrasia tabularis Seed

This study was conducted to investigate the variation in seed traits and nutrient contents among 26 provenances of Chukrasia tabularis from 8 countries in Asia and Australia. There were highly significant differences among provenances in seed length (range 5.77~8.82 mm), seed width (3.82~5.52 mm), seed thickness (0.59~0.82 mm), seed length-width ratio (1.41~1.77), 100-seed weight (0.81~1.52 g), and contents of soluble protein (14.12~51.65 mg?g-1), soluble sugar (10.36%~16.63%) and starch (18.83%~70.74%) in seed. Although provenances showed mixed performances across the seed parameters measured, seeds from Australia and Malaysia were generally larger and heavier, and had higher protein, sugar and starch contents than those from other countries. Significant correlations between seed traits and environmental attributes were observed. Nutrient contents were correlated negatively with altitude, suggesting that provenances from lower altitude had higher nutrient contents, and vice versa. Principal component analysis revealed that seed length, width and weight, and soluble protein, soluble sugar and starch contents were useful characteristics in explaining the variation pattern among provenances. This study indicates marked variation in seed size parameters and nutrient content among C. tabularis provenances and the influence of geographic location and climate on the variation.