Abstract:
In order to screen the drought-tolerant germplasm resources of soybean at germination stage, this study used 20% polyethylene glycol(PEG-6000) to simulate drought stress to identify the drought tolerance of 258 soybean resources at germination stage from home and abroad. The germination potential, germination rate, germination index, relative germination potential, relative germination rate, relative germination index and drought damage rate were used as identification indexes. Finally, the drought tolerance of soybean resources at germination stage was evaluated and clustered by membership function value. The results showed that there were significant differences among the stress treatments, and the correlation analysis showed that the membership function was positively correlated with each index, and the drought injury rate was negatively correlated with each index. According to the membership function, 258 germplasm resources were divided into 4 categories: There were 9 varieties(lines) of drought-tolerant, 55 varieties(lines) of sub-drought-tolerant, 186 varieties(lines) of sub-sensitive and 8 varieties(lines) of sensitive. The 258 materials were classified into 3 types by the subordinate function cluster analysis: 17 tolerant materials, such as Jilin xiaolidou 7, Dongda 2, etc., which accounted for 6.59% of the total materials, 99 intermediate materials, for example, Kenfeng 13 and Kennong 18 accounted for 38.37% of the total materials, and 142 sensitive materials, such as Heihe 38 and Longdou 2, accounted for 55.04% of the total materials. The results will provide suitable germplasm resources for drought-tolerant breeding and genetic mechanism of drought-tolerant in bud stage.