Shrestha Arjina, Buckley Thomas N, Lockhart Erin L, Barbour Margaret M
The Centre for Carbon, Water and Food, Faculty of Science, The University of Sydney, Sydney, Australia.
Department of Plant Sciences, University of California, Davis, CA, USA.
AoB Plants. 2018 Dec 11;11(1):ply073. doi: 10.1093/aobpla/ply073. eCollection 2019 Feb.
. Mesophyll conductance ( ) has been shown to vary between genotypes of a number of species and with growth environments, including nitrogen availability, but understanding of variability in legumes is limited. We might expect in legumes to respond differently to limited nitrogen availability, due to their ability to fix atmospheric N. Using online stable carbon isotope discrimination method, we quantified genetic variability in under ideal conditions, investigated response to N source (N-fixation or inorganic N) and determined the effects of N source and water availability on the rapid response of to photosynthetic photon flux density (PPFD) and radiation wavelength in three genotypes of chickpea (). Genotypes varied 2-fold in under non-limiting environments. N-fed plants had higher than N-fixing plants in one genotype, while in the other two genotypes was unaffected. response to PPFD was altered by N source in one of three genotypes, in which the response to PPFD was statistically significant in N-fed plants but not in N-fixing plants. There was no clear effect of moderate water stress on the response to PPFD and radiation wavelength. Genotypes of a single legume species differ in the sensitivity of to both long- and short-term environmental conditions, precluding utility in crop breeding programmes.
叶肉导度（ ）已被证明在许多物种的基因型之间以及随着生长环境（包括氮素有效性）而变化，但对豆科植物中叶肉导度变异性的了解有限。由于豆科植物具有固定大气中氮的能力，我们可能预期它们的叶肉导度对有限的氮素有效性会有不同的反应。使用在线稳定碳同位素判别方法，我们在理想条件下量化了叶肉导度的遗传变异性，研究了叶肉导度对氮源（固氮或无机氮）的反应，并确定了氮源和水分有效性对三种鹰嘴豆（ ）基因型中叶肉导度对光合光子通量密度（PPFD）和辐射波长快速反应的影响。在非限制环境下，基因型的叶肉导度变化了2倍。在一种基因型中，施氮植物的叶肉导度高于固氮植物，而在其他两种基因型中，叶肉导度不受影响。在三种基因型中的一种中，氮源改变了叶肉导度对PPFD的反应，其中施氮植物中叶肉导度对PPFD的反应具有统计学意义，而固氮植物中则没有。中度水分胁迫对叶肉导度对PPFD和辐射波长的反应没有明显影响。单一豆科物种的基因型在叶肉导度对长期和短期环境条件的敏感性方面存在差异，这使得其在作物育种计划中的实用性受到限制。
