棉花抗旱品种筛选鉴定及抗旱性综合评价方法

Screening and evaluation for drought resistance of cotton varieties

从甘肃敦煌、新疆的棉花栽培品种和国内外引进材料中选出76个遗传来源不同的棉花品种(系)作为参试材料,在年降雨量不足40 mm的甘肃省敦煌市设置了干旱胁迫和正常灌水两个处理,筛选出与棉花抗旱性密切相关的10个农艺性状和产量指标,采用综合抗旱系数(CDC)、综合抗旱指数(CDI)、综合隶属函数值(CDM)、抗旱性综合评价值(D)等四种综合评价方法对76份种质材料进行抗旱性评价。结果显示,四种综合评价方法两两之间的Pearson相关系数都在0.88以上,相关性均达到了极显著水平;再利用四种抗旱评价体系得分值对76个受试棉花品种(系)进行K-means划分聚类,最终将76个品种分为高抗(Ⅰ类,5个品种)、抗(Ⅱ类,9个品种)、中等(Ⅲ类,17个品种)、敏感(Ⅳ类,31个品种)、高敏(Ⅴ类,14个品种)5个抗旱等级。为进一步方便育种家简单准确地评价选育材料的抗旱性,利用筛选出的10个农艺性状指标的抗旱系数作为自变量,四种抗旱性综合评价体系得分值为因变量,采用逐步回归的方式建立了棉花抗旱性预测模型回归方程。

In order to screen the drought resistance of germplasm resources and develop cotton drought resistance evaluation system,76 different cotton varieties（ lines） were planted under drought stress and normal irrigation in Dunhuang City,Gansu province,where the annual rainfall is less than 40 mm. Drought resistance of 76 varieties（ lines） was evaluated by the investigation on 10 agronomic traits and yield index which is closely related to drought resistance of cotton,in combination with the comprehensive drought resistant coefficient（ CDC）,comprehensive drought resistant index（ CDI）,membership function values（ CDM） and drought resistance,drought resistance comprehensive evaluation values（ D） four method. The evaluation results of the four methods were basically the same,and then clustering analysis was performed. The 76 varieties were divided into High Resistance（ class I）,Resistance（ classⅡ）,Middle（ class Ⅲ）,Sensitive（ class IV） and High Sensitivity（ class V）. The resulting 10 agronomic traits of drought resistance coefficient as the independent variable,four kinds of comprehensive evaluation of drought resistance of score values as the dependent variable,can be used to establish the regression equation using stepwise regression method for predict drought resistance of cotton,facilitating the simple and accurate evaluation of the drought resistance of breeding germplasms.