South Australian Research and Development Institute, Waite Campus, Australia
South Australian Research and Development Institute, Waite Campus, Australia.
J Exp Bot. 2016 Jul;67(14):4339-51. doi: 10.1093/jxb/erw221. Epub 2016 Jun 13.
We measured yield components, nitrogen fixation, soil nitrogen uptake and carbon isotope composition (δ(13)C) in a collection of chickpea genotypes grown in environments where water availability was the main source of yield variation. We aimed to quantify the phenotypic plasticity of these traits using variance ratios, and to explore their genetic basis using FST genome scan. Fifty-five genes in three genomic regions were found to be under selection for plasticity of yield; 54 genes in four genomic regions for the plasticity of seeds per m(2); 48 genes in four genomic regions for the plasticity of δ(13)C; 54 genes in two genomic regions for plasticity of flowering time; 48 genes in five genomic regions for plasticity of nitrogen fixation and 49 genes in three genomic regions for plasticity of nitrogen uptake from soil. Plasticity of yield was related to plasticity of nitrogen uptake from soil, and unrelated to plasticity of nitrogen fixation, highlighting the need for closer attention to nitrogen uptake in legumes. Whereas the theoretical link between δ(13)C and transpiration efficiency is strong, the actual link with yield is erratic due to trade-offs and scaling issues. Genes associated with plasticity of δ(13)C were identified that may help to untangle the δ(13)C-yield relationship. Combining a plasticity perspective to deal with complex G×E interactions with FST genome scan may help understand and improve both crop adaptation to stress and yield potential.
我们测量了在水分可利用性是产量变化主要来源的环境中生长的一批鹰嘴豆基因型的产量构成因素、固氮作用、土壤氮吸收和碳同位素组成（δ(13)C）。我们旨在使用方差比来量化这些性状的表型可塑性，并使用 FST 基因组扫描来探索它们的遗传基础。在三个基因组区域中发现 55 个基因与产量可塑性相关；在四个基因组区域中发现 54 个基因与种子每平方米的可塑性相关；在四个基因组区域中发现 48 个基因与 δ(13)C 的可塑性相关；在两个基因组区域中发现 54 个基因与开花时间的可塑性相关；在五个基因组区域中发现 48 个基因与固氮的可塑性相关；在三个基因组区域中发现 49 个基因与土壤氮吸收的可塑性相关。产量的可塑性与土壤氮吸收的可塑性相关，而与固氮的可塑性无关，这突出表明需要更密切关注豆科植物的氮吸收。虽然 δ(13)C 与蒸腾效率之间的理论联系很强，但由于权衡和尺度问题，实际与产量的联系却不稳定。确定了与 δ(13)C 可塑性相关的基因，这可能有助于理清 δ(13)C-产量关系。将可塑性视角与 FST 基因组扫描相结合，以处理复杂的 G×E 相互作用，可能有助于理解和提高作物对胁迫的适应能力和产量潜力。
