海岛棉重组自交系群体花铃期抗旱性评价

Evaluation on Drought Resistance of Recombinant Inbred Lines of Gossypium barbadense L.at Flowering and Boll Stages

【目的】构建海岛棉分离群体,筛选抗、敏极端材料,为棉花抗旱种质改良和优质抗逆品种选育提供原材料,为棉花抗旱性研究提供基础。【方法】以双亲及海海重组自交系群体71个株系为材料,在花铃期进行田间自然干旱胁迫,通过测定形态指标和产量相关指标,采用方差分析、主成分分析、聚类分析等相结合的方法,对双亲及RILs家系进行抗旱性鉴定及评价。【结果】7个性状被分为植株形态及单株产量相关性状和纤维产量相关性状2个综合因子;RILs材料划分为较敏旱型(28份)、抗旱型(26份)、敏旱型(14份)和强抗旱型(3份)共4个类群。得到多元线性模型:D值=-0.771+0.089×DC_(株高)+0.117×DC_(有效果枝数)+0.132×DC_(铃数)+0.343×DC_(有效铃数)+0.338×DC_(单铃皮棉重)+0.230×DC_(单株籽棉产量)。【结论】筛选出强抗旱材料HH-16、HH-61、HH-70和敏旱材料HH-051、HH-05,可以应用于抗旱相关基因表达分析及抗逆种质创新研究。有效铃数、单铃皮棉重和单株籽棉产量可以作为棉花自交系田间抗旱性鉴定的主要指标。

【Objective】To provide raw materials for the improvement of drought-resistant cotton germplasm and breeding of high-quality stress-resistant varieties by constructing isolated populations of Gossypium barbadense L.and screening resistant and sensitive extreme materials,which provides a basis for future research on cotton drought resistance.【Methods】71 strains of parents and Haihai recombinant inbred line populations were takne as experimental materials,the field was subjected to natural drought stress at the flowering and boll stage,and morphological indicators and yield-related indicators were measured.Meanwhile,variance analysis,principal component analysis,and clustering analysis were employed simultaneously to identify and evaluate the drought resistance of parents and RILs families.【Results】Principal component analysis of 7 traits could be divided into two comprehensive factors:plant morphology,yield-related traits per plant,and fiber yield-related traits;based on the comprehensive drought resistance measure(D value)for systematic clustering,the RILs materials were divided into four groups:more drought-sensitive type(28),drought-resistant type(26),drought-sensitive type(14)and strong drought-resistant type(3).When the drought resistance coefficient of each trait was used as the independent variable and the D value as the dependent variable for regression analysis,a multivariate linear model was obtained:D value=-0.771+0.089×DC_(Plant height)+0.117×DC_(number of effective branches)+0.132×DC_(number of bells)+0.343×DC_(effective number of bells)+0.338×DC_(single boll lint weight)+0.230×DC_(Cotton yield per plant).【Conclusion】The strong drought-resistant materials HH-16,HH-61,HH-70 and the drought-sensitive materials HH-051 and HH-05 are screened out,which can be applied to the analysis of drought-related gene expression and the innovation of stress-resistant germplasm.The results of principal component analysis and multiple regression analysis show that the effective boll number,lint weight per boll and cotton yield per plant can be used as the main indicators for the identification of drought resistance of cotton inbred lines in the field.