Abstract: Results obtained from pot and field experiments showed that potassium deficiency stress restrained the growth of 81394, a variety sensitive to potassium deficiency, which had the genetic characteristics of high dry products and low potassium concentration. But different potassium application had little effect on the growing and potassium accumulation in Fujiandao, a variety tolerant to potassium deficiency. The K use efficiency (KUE) of Fujiandao was higher than that of 81394 under K deficiency condition at earlier growing stage, while it was just the opposite under potassium sufficient condition or at later growing stage. The K efficiency (KE) of Fujiandao was always higher than that of 81394. The nitrogen content and N/K were higher under K deficiency condition, which caused the nutrient unbalance in rice. Such appearance of 81394 was more distinct than that of Fujiandao. Potassium deficiency could also promote the sodium uptake and accumulation, especially in the root of Fujiandao, which meant sodium and potassium substitution in the root should be one of the mechanisms of high potassium deficiency tolerance.

Key words: rice, potassium, nutrient characteristic, nitrogen, sodium

摘要： 通过土培和大田试验，研究了不同供钾水平对两个耐缺钾能力不同水稻品种的氮钾钠等营养特性及其生长的影响。结果表明，不耐低钾的81394具有生物量大但体内钾素含量低的遗传特性，在缺钾条件下，其生长及钾素积累都受到明显抑制，而供钾水平的变化对耐低钾品种辐简稻的影响不大。缺钾条件下，生育前期辐简稻钾素利用效率大于81394，但生育后期及供钾充足时相反。钾效率表现为辐简稻始终大于81394。低钾胁迫使水稻体内含氮量增大，N/K升高，养分比例失调，81394表现更为显著。缺钾促进水稻对钠的吸收，在辐简稻根系中更为突出。

关键词: 水稻, 钾, 营养特性, 氮素