低钾胁迫下不同低钾耐性大豆钾营养特性的差异

Differences in Nutrition Characters of Potassium in Various Soybean Genotypes under Low Potassium Stress

采用盆栽试验方法研究了低钾胁迫对不同低钾耐性大豆品种(系)钾营养特性的影响。结果表明:低钾胁迫下,植株干重、单株粒重、叶片钾含量、茎秆钾含量、幼荚钾含量、籽粒钾含量和钾积累量均以耐性品种(系)较高,钾利用效率以低钾敏感品种(系)较高。低钾胁迫下,不同低钾耐性大豆的植株干重、单株粒重、各器官钾含量和钾积累量均下降,但耐性品种(系)的各指标下降幅度小,敏感品种(系)的各指标下降幅度大。低钾胁迫下,不同低钾耐性大豆的钾利用效率均明显升高,耐性品种(系)比敏感品种(系)的升高幅度小。耐性品种(系)的植株干重、单株粒重、各器官的钾含量、钾积累量和钾利用效率受低钾胁迫影响较小,低钾条件下耐性品种(系)获得较高产量的主要原因是吸钾能力更强。

The effects of low potassium stress on nutrition characters of potassium in soybeans with tolerance to low potassium condition were studied through potted experiment. The results showed that plant dry weight, seeds weight of per plant, content potassium of leaf, stem, young pod and seed, K accumulation were higher in tolerant varieties （lines） under low potassium stress, while K utilization efficiency was higher in sensitive varieties （lines） under low potassium stress. It was found that plant dry weight, seeds weight of per plant, potassium content of each organ and K accumulation in all tested soybean varieties （lines） decreased under low potassium stress. However, decreasing extent of each above indices of nutrition characters was smaller in low K-tolerant varieties （lines） than that in low K-sensitive varieties （lines）. On the contrary, K utilization efficiency of all tested soybean varieties （lines） was significantly improved under low potassium condition, and increasing extent in low-K sensitive varieties （lines） was larger than that in low-K tolerant varieties （lines）. In general, low potassium stress showed less effects on plant dry weight, seeds weight of per plant, potassium content of each organ, K accumulation and K utilization efficiency in low K-tolerant varieties （lines）, and the main reason which led to higher yield in tolerant varieties （lines） might be more potassium uptake.