Agronomic traits of tobacco germplasm resources resistant to brown spot disease and chemical compositions of cured tobacco leaves

ObjectiveThe agronomic traits and chemical compositions of tobacco germplasm resources resistant to brown spot disease were analyzed in order to provide reference for the parent selection of tobacco breeding and full utiliza-tion of the germplasm resources.MethodThe experiment was conducted in field,the field growth period,agronomic traits,economic characters and chemical compositions of 24 tobacco germplasm resources that were resistant to brown spot disease were analyzed,and principal component analysis and hierarchical cluster analysis were also conducted.Re-sultThe results showed that the growth period of all 24 tobacco germplasm resources showed great differences. The germ-plasm resources with suitable field growth period were Jingyehuang,Zhongyan 86,Yunyan 110,Yunyan 100 and Xiaofeng No. 8. Besides,Yunyan 100,Yunyan 110,8813 and Xiaofeng No. 8 were the germplasm resources with sound comprehensive agronomic traits. Yunyan 100,Yunyan 110,Xiaofeng No. 8,YA-2,Huishui-1,Huishui-2 and Zijiang No. 1 were the germplasm resources with fine main economic characters. Yunyan 100,Yunyan 110,Oxford 26,Danyu No.2 and Huishui-1 were the germplasm resources with coordinated chemical composition in middle tobacco leaves. YA-2,Huishui-1,Zijiang No.1,Yunyan 100,9042,Huishui-2,Coker spedlgreed,YQ-1,Fuyan No.6 and Yunyan 110 were the germplasm resources obtaining high comprehensive score in principal component analysis.ConclusionThere are great differences among various tobacco germplasm resources that are resistant to brown spot disease. Ten germplasm re-sources,including YA-2,Huishui-1,Zijiang No.1,Yunyan 100,9042,Huishui-2,Cokers pedlgreed,YQ-1,Fuyan No.6 and Yunyan 110,obtain high comprehensive score,so they can be used as parent materials for the breeding of new toba-cco varieties that are resistant to brown spot disease.