Abstract: Cultivating nine rice genotypes differing in their tolerance to low potassium stress that were selected from large volume solution screening under different K supply levels in the field, the results showed that low K stress reduced K accumulation and accelerated K translocation. Both the difference of K accumulation in shoots between low and high K supply treatments and the difference of K uptake ability among genotypes were relatively larger at early growth stage, then decreased at the later growth stage during the whole life span. Marked difference of relative K accumulation and translocation ability existed among the rice genotypes. The K efficient genotypes made better use of absorbed K, had higher accumulation of K in shoots at seedling growth stage and maintained higher K content in both upper leaves and lower leaves at booting stage under low K stress, as compared with K inefficient rice genotypes. Because of great ability for K translocation, K content differed greatly between upper leaves and lower leaves under low K stress for the efficient rice genotypes.

Key words: rice, potassium, accumulation, translocation, genotype

摘要： 经水培苗期筛选后选用对低钾胁迫抗性不同的9种水稻基因型进行田间试验，结果表明, 低钾胁迫减少水稻体内钾的累积量，增加体内钾的运转速率。不同钾处理间水稻地上部钾素累积量和同一处理内不同水稻基因型间吸钾能力在生育前期差异均较大，后期则相对较小。水稻体内钾累积与运转能力的基因型差异非常显著。与钾低效基因型相比，钾高效基因型低钾胁迫下苗期地上部钾素累积量较大，孕穗期上位叶和下位叶中钾含量均相对较高，上位叶、下位叶间钾含量的差异也较大。

关键词: 水稻, 钾, 累积, 转运, 基因型