Root xylem plasticity to improve water use and yield in water-stressed soybean.
Root xylem plasticity to improve water use and yield in water-stressed soybean.
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DOI：
10.1093/jxb/erw472
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发表时间：
2017-04-01
影响因子：
6.9
通讯作者：
Nguyen HT
中科院分区：
文献类型：
--
作者：
Prince SJ;Murphy M;Mutava RN;Durnell LA;Valliyodan B;Shannon JG;Nguyen HT
通过增加导管数量和减小导管直径来改变根木质部发育可塑性，可以提高大豆在水分限制条件下的吸水能力，减少产量损失。我们测试的假设，即增加后生木质部导管的数量将提高大豆（Glycine max）的水分吸收效率，并减少在水分有限的环境中的产量差距。在温室、防雨棚和雨养田环境中对41份大豆种质进行了评价。的后生木质部数量的影响内部捕获的CO2和改善气孔导度，提高水分的吸收/利用在大豆暴露于压力在生殖阶段。我们确定，其他根的解剖特征，如皮层细胞面积和中柱的百分比，包括皮层细胞，也影响种子产量在类似的生长参数。种子产量还受到干旱胁迫下的豆荚保留率（24-80个豆荚/植株）的影响。我们推测，有效的生物量分配，即在生殖生长后期（R6-R7）将有效的光合产物运输到花结构，能够在干旱胁迫下保护产量。对干旱胁迫下产量和根系解剖特征的对比系的围隔研究表明，作为对干旱的适应，高产系的后生木质部数量的增加提高了根系导水率，从而降低了探索深层土壤水分的代谢成本，增强了水分运输。这允许在水分有限的条件下维持芽的生理过程。
Altering root xylem developmental plasticity by increasing the number of vessels and decreasing their diameter enhances water uptake and reduces yield loss in soybean under water-limited conditions. We tested the hypothesis that increasing the number of metaxylem vessels would enhance the efficiency of water uptake in soybean (Glycine max) and decrease the yield gap in water-limited environments. A panel of 41 soybean accessions was evaluated in greenhouse, rainout shelter, and rain-fed field environments. The metaxylem number influenced the internal capture of CO2 and improved stomatal conductance, enhancing water uptake/use in soybeans exposed to stress during the reproductive stage. We determined that other root anatomical features, such as cortex cell area and the percentage of stele that comprised cortical cells, also affected seed yield under similar growth parameters. Seed yield was also impacted by pod retention rates under drought stress (24–80 pods/plant). We surmise that effective biomass allocation, that is, the transport of available photosynthates to floral structures at late reproductive growth stages (R6–R7), enables yield protection under drought stress. A mesocosm study of contrasting lines for yield under drought stress and root anatomical features revealed that increases in metaxylem number as an adaptation to drought in the high-yielding lines improved root hydraulic conductivity, which reduced the metabolic cost of exploring water in deeper soil strata and enhanced water transport. This allowed the maintenance of shoot physiological processes under water-limited conditions.