棉花品种资源全生育期抗旱性评价及抗旱指标筛选

为分析棉花品种资源全生育期抗旱性及筛选抗旱性评价指标，以238份抗旱性不同的棉花品种为材料，设置正常灌水和干旱胁迫两个处理，选取株高、铃数、单铃重及可溶性糖含量等指标，采用抗旱系数、主成分分析、关联分析和聚类分析相结合的方法对238份棉花品种进行抗旱性综合评价及抗旱指标筛选。结果表明：干旱胁迫对棉花全生育期生长有显著影响。以抗旱性度量值（D值）为主要参数，以加权抗旱系数（WDC值）和综合抗旱系数（CDC值）作为辅助参数，可以将238份棉花品种资源分为5类，第Ⅰ类（高抗旱型）10份、第Ⅱ类（抗旱型）61份、第Ⅲ类（中等抗旱型）84份、第Ⅳ类（敏感型）78份和第Ⅴ类（高度敏感型）5份。株高、单铃重、衣分及可溶性糖含量对干旱胁迫的反应较其他指标更为敏感，可作为棉花全生育期抗旱性评价的指标。上述结果为优质高产的抗旱棉花品种评价和选育理论依据。

Identification of Drought Tolerance During Whole Growth Period in Cotton Germplasm Resources and Resistance Index Screening

To identify drought-resistant cotton varieties and screen the identification index during the whole growth period, 238 cotton varieties with different drought resistance were treated with normal irrigation and drought stress during the whole growth period. The indexes of plant height, boll number, boll weight and soluble sugar content were selected, and drought resistance coefficient, principal component analysis, correlation analysis and cluster analysis were used to comprehensively evaluate the drought resistance of 238 cotton resources and screen the drought resistance index. The results showed that drought stress had a significant effect on the growth of cotton during the whole growth period. Taking drought resistance (D value) as the main parameter, weighted drought resistance coefficient (WDC) and comprehensive drought resistance coefficient (CDC) as auxiliary parameters, 238 cotton variety resources could be divided into 5 grades, including 10 of typeⅠ (high drought resistance), 61 of typeⅡ (drought resistance), 84 of typeⅢ (moderate drought resistance), 78 of typeⅤ (sensitive type) and 5 of typeⅤ (highly sensitive type). Plant height, boll weight, lint percentage and soluble sugar content were more sensitive to drought stress than other indexes, which could be used as indicators for evaluating drought resistance of cotton variety resources during the whole growth period. Above results provided theoretical basis and basic materials for the breeding of new drought-resistant cotton varieties.