Most of the Brazilian soils, especially in Cerrado biome, have high acidity and toxic aluminium, making the application of limestone an indispensable technique to obtain high yield in soybean crop. The hypothesis of this study was that contrasting base saturation provides changes in water‐use efficiency (WUE) and agronomic traits of soybean populations. Thus, we evaluated the WUE and agronomic performance of F₃ soybean populations under different base saturation levels. Each experiment was conducted in a randomized complete blocks design with three replicates and 10 F₃ populations (P1, P2, P3, P4, P5, P6, P7, P8, P9 and P10) for two crop seasons. Segregating populations were obtained by bulk method. In the first experiment, F₃ populations were evaluated without correction of base saturation (V = 30%), while in the second experiment, limestone was applied three months before sowing to increase base saturation to 60%. The traits evaluated were as follows: calcium, magnesium and potassium contents, water‐use efficiency (WUE), plant height, first pod height, main stem diameter and grain yield. Our findings indicate that WUE and agronomic performance of F₃ soybean populations depends on the saturation condition. We identified the P4 and P9 populations as the most promising for use in breeding programmes aiming at higher tolerance to abiotic stress caused by low base saturation in soil.

中文翻译：

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在相反的碱基饱和下生长的F3大豆种群的农艺表现和水分利用效率

巴西的大多数土壤，特别是Cerrado生物群落中的土壤，都具有高酸度和有毒的铝，使石灰石的应用成为获得大豆作物高产必不可少的技术。这项研究的假设是，相反的碱基饱和度可以改变大豆种群的水分利用效率（WUE）和农艺性状。因此，我们评估了在不同碱基饱和水平下F ₃大豆群体的水分利用效率和农艺性能。每个实验均按随机完整区组设计进行，三个重复和10个F ₃种群（P1，P2，P3，P4，P5，P6，P7，P8，P9和P10）用于两个作物季节。通过总体方法获得隔离种群。在第一个实验中，F ₃在不校正基本饱和度的情况下评估种群（V = 30％），而在第二个实验中，播种前三个月施用石灰石以将基本饱和度增加至60％。评估的性状如下：钙，镁和钾含量，水分利用效率（WUE），植物高度，第一荚果高度，主茎直径和籽粒产量。我们的发现表明，F ₃大豆群体的水分利用效率和农艺性能取决于饱和条件。我们确定P4和P9种群是最有希望用于育种计划的种群，其目的是对土壤中低碱饱和度引起的非生物胁迫具有更高的耐受性。