中文摘要：

以低钾耐性品种沈农6号和九农15，低钾敏感性品种铁丰31和GD8521为材料，通过盆栽试验研究了不同低钾耐性大豆品种的钾利用效率和吸收效率。结果表明：低钾胁迫下耐性品种的钾利用效率都显著提高，敏感性品种提高不显著；低钾胁迫下耐性和敏感品种钾吸收效率都呈下降趋势；此外，耐性品种低钾胁迫的籽粒钾利用效率、钾收获指数都显著高于施钾条件，敏感性品种两处理间无显著差别。综上所述，耐性品种与敏感性品种相比在低钾胁迫下依然能获得较高产量主要原因是具备更高的钾利用效率。

英文摘要：

In order to study K efficiency of different low K tolerant soybean varieties under low K stress, we carried out pot culture,with low K-tolerant soybean varieties Shennong 6 and Jiunong 15, low K sensitive soybean varieties Tiefeng 31 and GD8521 under low K stress and K applied treatment. Significant difference of K utilization efficiency was found in low K tolerant soybean between low K stress and K applied treatment ,while the K utilization efficiency of low K sensitive soybean between low K stress and K applied treatment was no significant difference. The K uptake efficiency of low K tolerant and low K sensitive soybean cuhivars declined under the low K stress. The grain yield K utilization efficiency and K harvest index of low K tolerant soybean cultivars under low K stress were significant higher than that under K applied treatment. However, no significant differences of low K sensitive soybean cultivars were found between low K stress and K applied treatment. These results implied that the higher K utilization efficiency caused the higher tolerance coefficient for the low K sensitive soybean cultivars.