不同基因型棉花苗期钾效率差异的初步研究

营养液培养条件下对86个棉花基因型苗期进行钾效率筛选,并对其中的28个进行了系统的研究。发现不同基因型之间钾效率存在显著差异,变幅为0.08～0.28;高效基因型与低效基因型相比,在低钾条件下.生长状况优势更明显,表现为出现缺钾的症状慢,叶片脱落晚,植株较大;施钾能明显促进棉花的生长发育,提高干物质积累,干物质分配趋势是地上部大于根部;钾含量分配规律是叶与茎含量相当,均大于根的钾含量,适钾时高低效基因型间钾含量差异不大,表明钾含量是比较稳定的,从而维持植物正常生理功能;钾积累量方面,低钾时,叶>根>茎,适宜钾时叶片钾积累量最大,但根与茎的积累量相当,表明施钾能促进钾向地上部运输和协调分配。低效基因型对钾反应敏感,钾积累量受不同钾处理影响较大,而高效基因型受不同钾水平影响较小,反应较为迟钝。

K-efficiency in Different Cotton Genotypes at Seeding Stage

Genotypic differences of potassium(K) efficiency among 86 cotton cultivars were investigated under water culture at seeding stage,28 typical cultivars were picked out for a series study. K-efficiency is notably different among them; the range was from 0. 08 to 0. 28. Under low K supply, high-efficiency genotypes grew much better than low-efficiency genotypes. For example, K-deficiency symptom appeared slowly, leaves fell off later and plant grew higher. Potassium could hasten growth and enhance dry matter accumulation. The dry matter weight of shoot was more than that of root. The K content of leaf was equivalent to that of stem, which was higher than root K-content, but K-content between different genotypes was much the same at normal K supply. That proved K-content was necessary to keep the plant's normal function. Under K deficiency, the K-accumulation of leaf is more than that of root, which is more than that of stem; but with proper K supply , root and stem had the same K-accumulation. That showed K application was able to enhance K- transportation and distribution. Low-efficiency genotypes was sensitive to different K treatment on K-accumulation, but high-efficiency genotypes was blunt on it.