Combining ability of parent and genetic value of combination in sugarcane under different environmental conditions

【Objective】The study aimed to screen out suitable parents and combinations for Nanning, Chongzuo and Laibin sugarcane area of Guangxi by analyzing general combining ability(GCA) of parent and genetic value(GV) of combination, and to provide theoretical basis and reference for reasonable use of germplasm resources and speeding up the breeding of new varieties.【Method】A total of 119 crossing combinations obtained from 129 home-bred in Guangxi and introduced parents were used as materials.The same experiment to assess combination was carried out in Nanning, Chongzuo and Laibin.The joint variance analysis of combination, parent and location for brix yield and brix was made.Both GCA of parent and GV of combination on brix yield and brix were investigated, and the similarity of GCA of parent and GV of combination between different sites were evaluated by correlation coefficient method.【Result】On both brix yield and brix, there were extremely significant difference in combination, female parent, male parent and location(P< 0.01, the same below).And there were significant difference in combination by location interaction on brix yield(P< 0.05, the same below).The results of GCA analysis of female showed that GT04-112, GT08-212, GT06-3283, FR00-306, ZZ50, GT04-1560, GT03-591, YZ99-596, GT02-761, GT11-639 performed higher GCA on brix yield and brix in Nanning.GT04-112, GT03-591, GT08-212, GT08-10, GT11-639, FR00-306, GT94-119, GT09-98, GT06-1215, K86-138 showed higher GCA on brix yield and brix in Chongzuo.YZ99-596, GT04-112, GT06-3283, YT00-236, LC03-296, YG24, GT05-1141, GT11-08, GT11-639, GT06-244 had higher GCA on brix yield and brix in Laibin.The results of male GCA showed that LT07-95, GT94-10, CP84-1198, ROC22, YT00-236, GT00-122, GT11-639, GT06-1238, YT03-373, YunY06-9 performed higher GCA on brix yield and brix in Nanning.ROC22, GT00-122, GT94-10, GT08-1497, LT07-95, YT93-159, YuanL8, GT03-1403, FR93-979, YT93-373 showed higher GCA on brix yield and brix in Chongzuo.PR83-1248, GT04-2679, GT04-1023, LT07-95, CP84-1198, YT00-236, ROC22, YZ06-80, YG22, GT08-1235 had higher GCA on brix yield and brix in Laibin.The results of GV of combination showed that GT08-212×GT94-10, FR00-306×LT07-95, YZ99-596×YT00-236, GT04-1560×CP84-1198, ZZ50×ROC22, GT03-591×YC90-33, GT02-761×ROC22, GT04-112×GT00-122, YT99-66×ROC22 and YZ99-596×CP01-1178 had higher GV on brix yield and brix in Nanning.GT06-1215×GT06-1238, GT03-591×YC90-33, GT04-112×GT00-122, GT94-119×ROC22, GT04-1560×CP84-1198, GT08-212×GT94-10, GT08-10×GT04-2679, GT02-761×ROC22, FR00-306×LT07-95 and GT11-639×GT03-2309 had higher GV on brix yield and brix in Chongzuo.GT04-112×L5-8, GT07-229×GT04-2679, GT06-3283×PR83-1248, YZ99-596×YT00-236, LC03-296×GT04-1023, YG24×LT07-95, GT06-244×CP84-1198, FR00-306×LT07-95, GT08-10×GT04-2679 and FR93-257×GT06-244 had higher GV on brix yield and brix in Laibin.The parental GCA and GV of combinations on brix yield and brix in the three experimental sites all presented extremely significant positive correlation, and the correlation coefficients were 0.411-0.745.Correlation coefficient of GCA and GV on brix yield and brix between Nanning and Chongzuo was the highest, and similarity was also the highest.【Conclusion】The GCA and GV on both brix yield and brix among three locations has reference value.The suitable parents and combinations should be respectively selected according to the local test results in Nanning, Chongzuo and Laibin.