Indices of drought tolerance in wheat genotypes at early stages of plant growth
Indices of drought tolerance in wheat genotypes at early stages of plant growth
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DOI：
10.1111/j.1439-037x.2004.00592.x
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发表时间：
2004-02-01
影响因子：
3.5
通讯作者：
Behl, RK
中科院分区：
文献类型：
--
作者：
Dhanda, SS;Sethi, GS;Behl, RK
在实验室条件下，对30个不同基因型的面包小麦种子活力指数、发芽率、根长、芽长、根冠比、胚芽鞘长度和渗透膜稳定性进行了测定。观察到所有性状都有相当大的变异。平均值的基础上的基因型之间的歧视是更好地在正常条件下比水分胁迫条件下，水分胁迫条件下的变异性抑制。在正常和渗透胁迫条件下的平均性能比较表明，种子活力指数是最敏感的性状，其次是芽长，发芽率和根长。根冠比，但在渗透胁迫下增加。一般而言，渗透胁迫下的遗传方差和遗传力的大小低于正常条件下。除发芽率、芽长和胚芽鞘长度外，其余性状均表现出较大的遗传变异。两种环境下所有性状的广义遗传力也都是中等偏高。叶段渗透膜稳定性和根冠比具有较高的遗传力和遗传先进性，可通过选择获得较大的效益。从根长和种子活力指数可以预期中等进展。相关性分析表明，叶段渗透膜稳定性是最重要的性状，其次是根冠比和根长。
Thirty diverse genotypes of bread wheat were evaluated for seed vigour index, germination percentage, root length, shoot length, root-to-shoot length ratio, coleoptile length and osmotic membrane stability under laboratory conditions. Considerable variation was observed for all the characters. Discrimination among the genotypes on the basis of mean values was better under normal than under moisture stress conditions, indicating suppression of variability under moisture stress conditions. Comparison of mean performance under normal and osmotic stress conditions indicated that the seed vigour index was the most sensitive trait, followed by shoot length, germination percentage and root length. The root-to-shoot length ratio, however, increased under osmotic stress. The magnitude of genetic components of variance and heritability were, in general, lower under osmotic stress than under normal conditions. All the characters except germination percentage, shoot length and coleoptile length showed considerable genetic variability. Heritability in the broad sense was also moderate to high for all the characters under both environments. Due to high heritability and genetic advance great benefit from selection can be expected for the osmotic membrane stability of leaf segments and root-to-shoot length ratio. Moderate progress can be expected from root length and seed vigour index. Correlation studies indicated that the osmotic membrane stability of the leaf segment was the most important trait, followed by root-to-shoot ratio and root length on the basis of their relationships with other traits.