Characterization of Drought-Tolerance Traits in Nodulated Soya Beans: The Importance of Maintaining Photosynthesis and Shoot Biomass Under Drought-Induced Limitations on Nitrogen Metabolism
Characterization of Drought-Tolerance Traits in Nodulated Soya Beans: The Importance of Maintaining Photosynthesis and Shoot Biomass Under Drought-Induced Limitations on Nitrogen Metabolism
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DOI：
10.1111/j.1439-037x.2011.00491.x
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发表时间：
2012-04-01
影响因子：
3.5
通讯作者：
Foyer, C. H.
中科院分区：
文献类型：
--
作者：
Fenta, B. A.;Driscoll, S. P.;Foyer, C. H.
干旱是限制大豆(Glyine max L.Merr.)田里的产量。因此，开展了以下研究，以确定提高结球大豆耐旱性的表型标记。比较了水分充足条件下3个三叶期生物量和光合作用相近的品种Prima 2000、抗草甘膦品种A5409RG和Jackson的叶片和根瘤参数。三叶叶保水后，光合作用、根瘤数、根瘤生物量和共生固氮能力显著下降。在光合作用方面，品种间存在显著的交互作用，与根瘤固氮量呈显著正相关，特别是在干旱条件下。初生叶具有较高的水分利用效率，在长期干旱条件下也保持较高的光合作用电子传递效率。此外，在水分充足和干旱条件下，Prima的地上部生物量都最高。A-5409RG是对干旱最敏感的品种，表现为气孔提前关闭，光合作用对干旱的反应迅速受到抑制。结果表明，在氮素限制条件下维持地上部生物量的能力是一个重要的参数，可用于大豆抗旱性种质资源的筛选。
Drought is the single most important factor limiting soya bean (Glycine max L. Merr.) yields in the field. The following study was therefore undertaken to identify phenotypic markers for enhanced drought tolerance in nodulated soya beans. Leaf and nodule parameters were compared in three genotypes: Prima 2000, glyphosate-resistant A5409RG and Jackson, which had similar shoot biomass and photosynthesis rates at the third trifoliate leaf stage under water-replete conditions. When water was withheld at the third trifoliate leaf stage, photosynthesis, nodule numbers, nodule biomass and symbiotic nitrogen fixation (SNF) were greatly decreased. Significant cultivardrought interactions were observed with respect to photosynthesis, which also showed a strong positive correlation with nodule SNF, particularly under drought conditions. Prima leaves had high water-use efficiencies, and they also maintained high photosynthetic electron transport efficiencies under long-term drought. Moreover, Prima had the highest shoot biomass under both water-replete and drought conditions. A-5409RG was the most drought-sensitive genotype showing early closure of stomata and rapid inhibition of photosynthesis in response to drought. In addition to classifying the genotypes in relation to drought tolerance, the results demonstrate that the ability to sustain shoot biomass under nitrogen limitation is an important parameter, which can be easily applied in germplasm screening for drought tolerance in soya bean.