Department of Chemistry and Biotechnology, Faculty of Science, Engineering and Technology, Swinburne University, PO Box 218, Hawthorn, Vic, 3122, Australia.
Department of Plant Sciences, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA.
New Phytol. 2018 Mar;217(4):1475-1483. doi: 10.1111/nph.14918. Epub 2017 Nov 27.
In nonagricultural systems, the relationship between intrinsic water-use efficiency (WUE ) and leaf nitrogen (N ) is known to be stronger for legumes than for nonlegumes. We tested whether these relationships are retained for major agricultural legumes and nonlegumes. We compared the response to N nutrition of WUE (and its component parts, photosynthesis (A ) and stomatal conductance (g )) for legumes Cicer arietinum, Glycine max, Lupinus alba and Vicia faba, nonlegume dicots Brassica napus and Helianthus annus, and nonlegume cereals Hordeum vulgare and Triticum aestivum. Surprisingly, and in contrast to studied cereals and nonlegume dicots, N was positively related to photosynthesis in the legumes, explaining nearly half of the variance in A . WUE was tightly coupled to N for agricultural legumes and nonlegume dicots, but not for cereal crops. Our analysis suggests that breeding efforts to reduce g in legumes could increase WUE by 120-218% while maintaining A at nonlegume values. Physiologically informed breeding of legumes can enhance sustainable agriculture by reducing requirements for water and N.
在非农业系统中，豆科植物的内在水分利用效率（WUE）与叶片氮（N）之间的关系强于非豆科植物。我们测试了这些关系是否适用于主要的农业豆科植物和非豆科植物。我们比较了豆科植物鹰嘴豆、大豆、白 Lupinus 和 Vicia faba、非豆科双子叶植物油菜和向日葵，以及非豆科谷物大麦和小麦对氮营养的响应，比较了 WUE（及其组成部分光合作用（A）和气孔导度（g））的响应。令人惊讶的是，与研究过的谷类作物和非豆科双子叶植物相比，氮与豆科植物的光合作用呈正相关，解释了 A 变异的近一半。农业豆科植物和非豆科双子叶植物的 WUE 与 N 紧密相关，但谷类作物则不然。我们的分析表明，为减少豆科植物的 g 而进行的育种工作可以将 WUE 提高 120-218%，同时保持非豆科植物的 A 值。通过减少对水和氮的需求，生理上有针对性的豆科植物育种可以增强可持续农业。
