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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]

[Objective] The present paper aimed to explore the excellent genes of germplasm resources of Tiebt barley and provide high-quality materials for breeding. [Method] The genetic diversity, clustering and principal component analysis of 13 agronomic traits were carried out by using Excel and SPSS 21. 0 software with 140 germplasm resources from different areas of Tibet [Result] There was rich genetic diversity in barley resources in Tibet, and the coefficient of variation of panicle number per plant among 8 agronomic traits was 43.7%. Cluster analysis divided the 140 materials into five groups at the genetic distances of 6 level, of which 3 5 materials were in group I, 29 materials were in group II, 33 materials were in group Ill, 15 materials were in group N and 28 materials were in group V. The results of principal component analysis showed that when the 8 agronomic traits were simplified into 3 principal components, the cumulative contribution rate was 72. 587 %, and the contribution rate of panicle per plant was the highest, which was 0. 829. [Conclusion] The study provides a scientific basis for the protection and utilization of germplasm resources in Tibet. [ABSTRACT FROM AUTHOR]

[Objective] The objective of the paper is to explore the different in quality characters of different pepper germplasm resources and to provide the scientific basis for development and utilization of pepper geemplasm me and new variety being [Method] The tent of erade fat, crude fiber, vitamin C and capsaicin if 80 pepper geemplasm is determined by acid hydrolysis and HPLC method, and then the quality traits are comprehensively evaluated by membership function method (Results ) The crude fat content of 80 pepper germplasm resources is 0.14-0.72 g/100g and the highest in bead-shape pepper with an average 0.51 g/100g The scale fat content of 80 pepper germplasm resources with different shape is bead-shape> hom-shape> line-shape > Finger-shape. The crude libero 80 pepper germplasm resources is 1 61-12.95 g/100g and the highest in Tine-shape pepper with an age of:9.60 g/100g The cade fiber content of 80 pepper germplasm resources with different shape is line-shape> heal-shape > finger-shape>horn-shape. The vitamin Conte of 80 pepper germplasm resources is 59.00-233.20 mg/100g and the highest in line-shape pepper with an age of 170.67 mg/100g The vitamin C content of 80 pepper germplasm resources with different shape is line-shape> horn-shape> bead-shape >finger-shape. The capsaicin content of 80 pepper germplasm resources is 1,66-83 11 mg/100g and the highest in finger-shape pepper with an average of 1. 39 mg/100g. The capsaicin content of 80 pepper germplasm resources with different shape is finger-shape >bead-shape>line-shape> horn shape. The average membership of four quality traits is 0.15-0.74. The best quality resources greater than 0.60 are Qian La 8261, Gui La 7002, Qingfeng 1086, Qian La 8250, Gangshan Honghu, Xingxiu and Zhuzijiao No. 1; 80 pepper germplasm resources can be gathered into high quality and medium quality And 3 types of general quality. [Conclusion] Seven resources with the best quality, Qianla 8261, Guila 7002, Qingfeng 1086, Qianla 8250, Gangshan Honghu, Xingxiu and Zhuzijiao No. 1, were selected, which can be used as high-quality resources in the breeding process. The basic material is optimized and improved by hybridization with other materials. for bending improvement during breeding process. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to reveal the genetic diversity of blaslogenesis by phenotypic characters of walnut in Xinjiang, aiming to provide the basis for classification, determination and utilization of germplasm resources of walnut in Xinjiang. [Method] Based on the comprehensive survey on germplasm resources of walnut, phenotypic character indexes and data were collected. Simpson (D) and Shannon-Weaver indexes (H') were used to conduct diversity test on polymorphism of qualitative characters, and classify the sample test of walnut germplasm through hierarchical clustering according to phenotypic character. [Result] The five quantitative characters of walnut complied with normal distribution in K-S test. The range of variations in three-diameter mean value was from 19. 14 to 46.59 mm. Among the polymorphism indexes of phenotypic and qualitative characters in walnut, the base section and shoulder section containied high levels of I) and H'. Germplasm walnuts were classified into nine categories, which were related to phenotypic characters, such as sizes, shapes and shells, rather than geographical distribution. [Conclusion] Phenotypic character and diversity analysis make it possible to assess the diversity of walnut germplasm resources in Xinjiang. Besides, it also demonstrates the high level for the diversity and phenotypic characters of local walnut germplasm resources in Xinjiang, containing abundant genetic resources and tremendous potential of utilization and development. [ABSTRACT FROM AUTHOR]