Abstract:Breeding for drought-tolerance varieties is one of the most cost-effective ways to meet global climate drought, and identification of the drought-tolerance germplasms is of importance in breeding. In this study, 303 mungbean accessions were tested for drought tolerance under the different irrigation conditions in Qitai Xinjiang in 2017 and 2018. Nine parameters were investigated, for instance yield per plant, pod number per plant, seed number per plant and biomass per plant. The ratios of all parameters between drought and irrigation condition were calculated. The drought tolerance indicators were determined by correlation analysis, and mungbean germplasm for drought-tolerance were evaluated by drought tolerance coefficient, subordinative function analysis and drought tolerance index. Based on the identified suitable evaluation method, we conducted the screening for drought-tolerance germplasm. The significant positive correlations on drought tolerant coefficient were observed between drought and irrigation conditions for pod number per plant, seed number per plant, biomass per plant and yield plot. The four indices were recommended for drought tolerance identification in mungbean. The correlations were significant among parameter values of three evaluation methods with a very high consistency. The drought tolerance germplasm resources, which were identified by the drought tolerance index, exhibited higher average yield per plant than by the two other methods under different water regimes. This results implied that the drought tolerance index was optimal to screen a large number of germplasm resources of mungbean at natural condition. 103 accessions, which showed identical results in 2017 and 2018, were finally identified. That included 9 varieties with high tolerance, 11 with tolerance, 61 with moderate tolerance, 8 with susceptibility, and 14 with high susceptibility. This results will provide theoretical guidance and basic information for future study on drought tolerance of mungbean.