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【Objective】The present paper aimed to establish the evaluation method of heat resistance of leek resources, select heat-resistant leek varieties, and solve the problem of shortage of heat-resistant leek varieties in Guangxi.【Method】Taking three kinds of local germplasm resources of leek（marked as A, B, C, D, E, F, G, H and I, respectively） of Guangxi large leaf leek, wide leaf leek and thin leaf leek collected from the general survey of germplasm resources by Ministry of Agricultural and Rural Affairs（2015-2020） as test materials, the changes of the maximum growth length of leek leaves, the newly increased aboveground biomass and the contents of chlorophyll, proline and malondialdehyde after 7 days of high temperature stress at 38 ℃ were measured. Combined with field natural high temperature stress（field group） actual heat resistance performance, the heat resistance of different types of leek was comprehensively evaluated by multivariate statistical analysis（variance analysis, principal component analysis, membership function method and cluster analysis） methods.【Result】Under high temperature stress of 38 ℃,the maximum leaf growth length and the newly increased biomass of 9 leek germplasms of the three types in Guangxi were extremely significantly decreased compared with their proper temperature control（CK）（P＜0.01）.The largest decline was the type of large-leaved leek, and the smallest decline was the type of fine-leaved leek. Chlorophyll content decreased to different degrees, of which the largest decline was the type of leek with large leaves, and the smallest decline was the type of leek with thin leaves. The content of MDA increased to different degrees, of which the largest increase was the type of leek with large leaves, and the smallest increase was the type of leek with thin leaves. Pro content increased to different degrees, of which, the largest increase was the type of leek with thin leaves, and the smallest increase was the type of leek with large leaves. The comprehensive evaluation results showed that the heat tolerance of the three kinds of local leek germplasm resources of leek in Guangxi was ranked as follows: leek with thin leaves＞leek with broad leaves＞leek with large leaves. Germplasm G（No.2016451159） and Germplasm I（No.2016453604） had the strongest heat tolerance among the nine leek germplasms, and Germplasm C（No.SC20191200） had the weakest heat tolerance.【Conclusion】The maximum growth length of leaves, new aboveground biomass and the content of chlorophyll, Pro and MDA contents were used as the evaluation indicators of heat tolerance of leek germplasm resources, the heat tolerance of three kinds of leek germplasm resources in Guangxi can be ranked as follows: Leek with thin leaves＞ leek with broad leaves＞leek with large leaves by variance analysis, principal component analysis, membership function and cluster analysis. Germplasm G and germplasm I were determined to be more heat-resistant, while germplasm C was the least heat-resistant. [ABSTRACT FROM AUTHOR]

The present paper aimed to analyze and evaluate the agronomic characters of cowpea varieties, and provide reference for screening cowpea varieties suitable for cultivation in N anning and its surrounding areas. [ Method] A comparative experiment of six cowpea varieties was carried out in Suwei Town, N anning City, Guangxi. Thirteen agronomic characters including double pods rate, high yield, pod longitudinal diameter, single pod weight and disease resistance were measured, and the correlation, principal component analysis and cluster analysis were used for comprehensive evaluation. [ Result] Correlation analysis showed that the number of branches per plant was the main reason affecting the number of seeds per pod and the number of main stem nodes. The length and width of pods were restricted by double pod rate and commercial pod rate. The rate of commercial pods and the number of main stem nodes had the greatest influence on single pod weight, and the increase of plant incidence would lead to the decrease of single pod weight. The results of principal component analysis showed that the cumulative contribution rate of variance of 13 agronomic characters of Guixiang No. 1, Gannong Chaoxnan and Chaoyue 708 ranked the top 3, and their comprehensive scores were 80. 37165,57. 56157 and 30. 08979,respectively. The top three varieties with comprehensive scores were Treasures No. 5,Jindou No. 8 and Taicheng Qianfeng, with comprehensive scores of -44. 20257, -50.45963 and -73. 36081, respectively. Cluster analysis showed that six cowpea varieties could be divided into two groups at the Euclidean distance of 15, among which Guirong No. 1, Gannong Chaoxnan and Chaoyue 708 in I group were characterized by high yield and strong disease resistance. Treasures No. 5, Jindou No. 8 and Taicheng Qianfeng of the second category had precocious characteristics. [Conclusion] Cowpea varieties Guijin No. 1, Gannong Chaoxnan and Chaoyue 708 have good performances in Suxu Town,Nanning City, Guangxi in yield and disease resistance, and are suitable for large-scale planting in Nanning and its surrounding areas. [ABSTRACT FROM AUTHOR]