Combining Ability Analysis on Quality Traits and Breeding Potential Evaluation of 23 Waxy Maize Lines from Laos
[Objective]High-quality is the primary target for waxy maize breeding.The aim of this study is to screen lines with high general combining ability and excellent hybrids with high-quality traits,which will clarify the breeding potential of these lines from Laos and lay a foundation in breeding high-quality waxy maize varieties.[Method]Using the Maize6H-60K chip,high quality genotype data of 33 waxy maize materials were obtained for cluster analysis.Combined with the iodine staining experiment and molecular detection of waxy genes,these types of waxy genes from early-generation maize lines from Laos were identified.Through the incomplete diallel cross experiment,phenotype identification and combining ability analysis of quality and other traits of 439 combinations were carried out to clarify the breeding potential of waxy maize lines with early generation from Laos.An experiment of quality traits evaluation with multi-person was conducted on these selected combinations with advantages to identify the most promising high-quality waxy maize hybrids.[Result]Clustering analysis was conducted based on 56 626 high quality SNP,and the results showed that these lines from Laos and domestic materials belong to different branches and can be clearly distinguished.All 23 lines with early generation from Laos were waxy maize,among which 16 lines belonged to the wx-D10 type,three lines belonged to the wx-D7 type,and the other four lines were unknown types.The heritability of quality traits of waxy maize materials from Laos is low,ranging from 0.14 to 0.35,which is suitable for selection in higher generations.The average stewing quality of 439 combinations was significantly higher than that of the control Jingkenuo2000 and Shinuo2,but there was no significant difference from Yunuo7.The general combining ability effects of all quality traits of waxy maize lines F02,F22,F25,and F28 were positive,which could be used to improve quality traits of domestic waxy maize in China.Furthermore,these combinations M02×F02 and M22×F22 were evaluated as excellent in multi-person quality traits evaluation experiments by approximately 86%of all tasters.[Conclusion]These local varieties of waxy maize from Laos have rich genetic variation,with a certain genetic distance from domestic waxy maize inbred lines.There may also exist new alleles of waxy gene in these lines from Laos.In addition,these waxy maize lines from Laos have obvious advantages in quality traits,including waxy quality,pericarp thickness and other traits,which can be used as valuable germplasm for improving the quality traits of domestic waxy maize in China.