不同类型大豆花荚期抗旱性形态指标及其综合评价

MORPHOLOGICAL INDEXES OF DROUGHT RESISTANCE OF SOYBEAN ACCESSIONS AND ITS COMPREHENSIVE EVALUATION ON FLOWERING AND PODDING STAGE

利用相关、主成分、聚类和判别分析,对野生、半野生大豆和栽培品种抗旱相关的形态指标与抗旱性的关系进行比较研究。结果表明:在干旱胁迫下,株高、株重、分枝数、株荚数、株粒数、百粒重、单株产量均有不同程度的降低,而叶片黄化脱落节位有所增加,且不同基因型存在差异;在干旱胁迫下抗旱系数与株高、株重呈显著正相关,与叶片黄化脱落节位呈显著负相关;主成分分析中的3个主成分,方差累积贡献率达88.38%;在聚类的基础上用判别分析确立了相对株高、叶片黄化脱落节位、背面茸毛密度、相对百粒重和抗旱系数5个对品种抗旱性分类有显著影响的指标,根据这些指标将供试15份大豆种质划分为高抗、抗、敏感、高度敏感4个类型;供试的野生、半野生大豆材料均划分在高抗旱类型中。优良的耐旱性种质和鉴定指标的发掘,为培育耐旱大豆新品种提供了必要的保证。

Correlation,cluster,principal component and discrimination analysis techniques were used to study the relationship between several morphological indexes and drought resistance of wild,semi-wild and cultivated soybean.The results showed that under drought stress,plant height,plant weight,branchy number,pods/plant,seeds/plant,100-seeds weight and yield/plant declined in different degrees,while the nodes position of fallen leaves increased depending on the tested genotypes.Drought resistance coefficients were significantly positively correlated to plant height,plant weight under drought stress,and were significantly negatively correlated with nodes position of fallen leaves.Principal component analysis was performed to select the first three principal components and their cumulative contribution of variance accounted for 88.38%.Cluster analysis had been used to classify the drought resistance of soybean,and by means of discrimination analysis,such indexes as relative plant height,nodes position of fallen leaves,relative 100-seeds weight,pubescence density on leave downer surface blade and drought resistance coefficient were selected.15 different soybean genotypes were classified into high resistance,medium resistance,sensitive and high sensitive groups according to these indexes.Wild and semi-wild soybean belonged to high resistance,so it is important to utilize the excellent and droughttolerant germplasm breeding the new soybean varieties.