Abstract:
【Objective】 To screen out the yield index and drought resistance of rapeseed varieties with strong drought resistance, so as to lay a foundation for breeding drought resistance varieties. 【Methods】 Under the conditions of dry-land, the agronomic traits of the materials were first compared to analyze whether there was any difference between the materials. Secondly, the drought resistance identification yield index (DRC, SSI, DRI, DI) of the materials. Comparative analyses of index, DRI and DI were carried out. Finally, suitable drought resistance identification yield indicators were selected, and rapeseed varieties with strong drought resistance were screened in the tested materials. 【Results】 The results showed that the plant height and yield of 25 tested rapeseed varieties under different drought stresses decreased to varying degrees, and the differences among the materials were significant. Among the drought resistance identification yield indicators, (1) DRC and SSI could be used to evaluate the stability of the variety, but cannot reflect the yield of the dry land; (2) The DRI did not only investigate the yield stability of rape varieties, but also took into account the dryland yield, and compared with the average yield of the same group of dryland, which was more suitable for the identification of drought resistance of rapeseed varieties. (3) The revision formula of DI utilized the yield of the control varieties, which was the same as the trend of drought resistance ability of the tested rape varieties reflected by the DRI. By taking into account the absolute yield and drought resistance coefficient of the tested varieties in dryland and water land, the high yield and drought resistance of the tested varieties were evaluated. Therefore, the DRI and DI were suitable for the comprehensive drought resistance identification of rapeseed varieties. On this basis, among the three types of test materials, according to the DRI, DI and the two habitats (drought-land and water-land), Qingza 12, Qingza 11, Dalajie, Yao 328-331 and Dahuang were selected. 【Conclusion】 The DRI and DI of rapeseed drought resistance varieties are suitable for comprehensive evaluation and identification of drought resistance. The drought resistance varieties selected from 25 rapeseed resources based on screening indicators are Qingza 12, Qingza 11, Dalajie, Yao 328-331 and Dahuang.