棉花抗枯、黄萎病品种苗期耐低钾种质筛选研究

本研究采用蛭石栽培和营养液浇灌的方法，确立棉花品种苗期耐低钾筛选指标，利用这些指标，评价我国88个抗枯、黄萎病棉花品种资源苗期耐低钾能力，并筛选钾素利用率高的优异种质。结果表明，株高、地上部干物重、地下部干物重、总干物重、钾利用率、叶绿素含量在不同钾浓度处理和不同品种之间均存在显著差异，可以作为棉花苗期耐低钾能力的评价指标，而叶面积在不同品种和不同钾浓度处理之间不存在差异。利用筛选出的指标对88个品种进行耐低钾评价，结果供试品种主要被分为耐低钾基因型、耐低钾中间类型和非耐低钾基因型三类，分别包括21个、58个和6个品种。

Identification and Screening of Low Potassium Tolerant Cottons with Fusarium and Verticillium Wilts Resistance at Seedling Stage

In the study, vermiculite culture and nutrition solution irrigation were performed to study the screening index related with low potassium tolerance cottons at seedling stage in order to estimate the low potassium-tolerance ability of 88 cotton varieties with Fusarium and Verticillium wilts resistance in China. The results showed that six screening indices, including plant height, dry weight, root dry weight, total dry weight, potassium use efficiency and chlorophyll content, had significant difference among different potassium concentrations and among cotton varieties. They could serve as the screening indices of potassium tolerance at cotton seedling stage. According to these indices, 88 cotton varieties were divided into three types, including tolerance (21), intermediate (58) and unendurable potassium genotypes (6).