Department of Soil Science, University of Zanjan, Zanjan, Iran.
Department of Soil Science Faculty of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
Sci Rep. 2018 Feb 8;8(1):2679. doi: 10.1038/s41598-018-20968-z.
We studied the effects of soil matric potential and salinity on the water use (WU), water use efficiency (WUE) and yield response factor (Ky), for wheat (Triticum aestivum cv. Mahdavi) and bean (Phaseoulus vulgaris cv. COS16) in sandy loam and clay loam soils under greenhouse conditions. Results showed that aeration porosity is the predominant factor controlling WU, WUE, Ky and shoot biomass (Bs) at high soil water potentials. As matric potential was decreased, soil aeration improved, with Bs, WU and Ky reaching maximum value at -6 to -10 kPa, under all salinities. Wheat WUE remained almost unchanged by reduction of matric potential under low salinities (EC ≤ 8 dSm), but increased under higher salinities (EC ≥ 8 dSm), as did bean WUE at all salinities, as matric potential decreased to -33 kPa. Wheat WUE exceeds that of bean in both sandy loam and clay loam soils. WUE of both plants increased with higher shoot/root ratio and a high correlation coefficient exists between them. Results showed that salinity decreases all parameters, particularly at high potentials (h = -2 kPa), and amplifies the effects of waterlogging. Further, we observed a strong relationship between transpiration (T) and root respiration (Rr) for all experiments.
我们研究了土壤基质势和盐分对水利用（WU）、水分利用效率（WUE）和产量响应因子（Ky）的影响，在温室条件下，研究了砂壤土和粘壤土中小麦（Triticum aestivum cv. Mahdavi）和菜豆（Phaseoulus vulgaris cv. COS16）的水利用、水分利用效率和产量响应因子。结果表明，在高土壤水势下，通气孔隙度是控制 WU、WUE、Ky 和地上生物量（Bs）的主要因素。随着基质势的降低，土壤通气性得到改善，在所有盐度下，Bs、WU 和 Ky 在-6 至-10 kPa 达到最大值。在低盐度（EC≤8 dSm）下，随着基质势的降低，小麦 WUE 几乎保持不变，但在较高盐度（EC≥8 dSm）下，小麦 WUE 随着基质势的降低而增加，在所有盐度下，菜豆 WUE 也是如此。在砂壤土和粘壤土中，小麦 WUE 均高于菜豆。两种植物的 WUE 随着地上/地下比的增加而增加，它们之间存在高度的相关性。结果表明，盐分降低了所有参数，特别是在高势（h=-2 kPa）下，并且放大了渍水的影响。此外，我们还观察到所有实验中蒸腾（T）和根呼吸（Rr）之间存在很强的关系。
