低钾胁迫下两个不同钾效率棉花基因型的生长及营养特性研究

 【目的】研究钾高效高增产潜力基因型和钾低效低增产潜力基因型棉花对低钾胁迫反应的差异。【方法】以筛选获得的钾高效高增产潜力棉花基因型103和钾低效低增产潜力棉花基因型122为材料，在盆栽条件下，设置不施钾和施钾（0.4 g•kg-1）处理进行全生育期试验。【结果】钾胁迫条件下，103生长状况良好，只有下部叶有轻微缺钾症状，122下部到中、上部叶片均有缺钾症状；103干物较重大，缺钾和施钾时其根系干重分别为122的1.07倍和1.26倍。说明103的根系发育较好，为其具有较强的吸收能力提供了物质基础。103在缺钾和施钾时的主茎干重分别是122的1.13倍和1.07倍，说明103具有较强的运输功能。103干物质和钾素的分配主要供应棉桃，缺钾和施钾时103棉桃干重分别是122的2.58倍和1.90倍。缺钾时103棉桃钾素的积累量是122的1.98倍，施钾时122桃的钾积累量只有103的49.6%。而其它营养器官则相对较少，所以103对有机物和钾素的转运能力强、分配较为合理; 103钾素经济利用率高，是122的近2倍。【结论】钾高效高增产潜力棉花基因型103与钾低效低增产潜力棉花基因型122的差异主要表现在对钾素吸收、转运、分配和利用等方面的高效。

Different Responses to Potassium Stress Between Potassium High Efficiency and Potassium Low Efficiency Cotton Genotypes Etficiencv and potassium Low Efficiency Cotton Genotypes

Abstract:【Objective】Based on screening from 86 cotton cultivars (Gossypium hirsutum L.), different responses to potassium stress between high K-efficiency and high yield potential cotton genotype103 (HKHP103) and low K-efficiency and low yield potential cotton genotype 122 (LKLP122) were studied.【Method】The research carried out by using pot experiment at different K levels (-K: 0.0 g/Kg and +K: 0.4 g/Kg).【Result】The result showed that HKHP103 grew much better than LKLP122. Only down leaves appeared Potassium deficiency symptoms for HKHP103, but to LKLP122, all of up、middle and down leaves appeared potassium deficiency symptoms. Dry matter weight was also different between them. Root dry matter weight of HKHP103 was 1.07 and 1.25 times of LKLP122 under －K and +K conditions, Which showed that the root of HKHP103 developed better than that of LKLP122. At －K and +K treatment, the main shoot of HKHP103 was 1.13 and 1.07 times of LKLP122, which showed that HKHP103 had a strong transport organ. The distribution of dry matter and potassium was mainly to boll organ for HKHP103, the boll dry matter weight of HKHP103 was 2.58 times of LKLP122 at －K treatment, and 1.90 times at +K treatment. As for potassium accumulation in boll, HKHP103 was 1.98 times of LKLP122 at －K treatment, and LKLP122 was 49.6％ of 103 at +K treatment. Boll was a propagation organ, but for vegetable organs, the distribution of dry matter and potassium was very little. As a result, 103 had an ability to transport and distribute the organic matter and accumulated potassium effectively, and its rate of K utilization was about 2 times of LKLP122. 【Conclusion】The reason why 103 was a high K-efficiency and high yield potential cotton genotype was due to its ability of high absorption、transportation、distribution and utilization for organic matter and potassium.