Cane yield and sucrose content are the two main breeding objectives in sugarcane,and plant height,stem diameter,and brix are major constituent factors of cane yield and sucrose.Identification of associated molecular markers and exploring elite alleles with yield and sucrose traits could provide a theoretical basis and reference for marker assisted breeding of sugarcane.In this study,62 sugarcane germplasm entries were used as the experimental materials.Three breeding traits,including plant height,stem diameter,and brix were investigated under four planting environments at maturity stage.ANOVA,genetic variation analysis and association analysis between the identified from related markers for further allele effect analysis.The result of ANOVA re-vealed that genotype,planting environment and their interaction had significant effect on plant height,stem diameter and brix in sugarcane.The broad-sense heritability of the three traits ranged from 0.68 to 0.76,indicating that they had stable genetic charac-teristics and their phenotype was mainly determined by its genotype.The frequency of these three traits showed typical quantita-tive traits with normal distribution characteristics.The coefficients of variation of the three traits ranged from 6.73％to 19.89％,suggesting a rich variation in phenotypes.A total of 204 alleles were found with a mean of 5.5135 per marker.The average gene diversity coefficient was 0.6779,and the average PIC value was 0.6252.The 89.19％of total markers were highly polymorphic with PIC＞0.5.Population structure analysis revealed that the tested group could be divided into three subgroups.A total of 20 markers were detected associated with plant height,stem diameter,and brix traits based on MLM method,which explained 5.04％-27.98％of phenotypic variation.Seven of them detected in two or more planting environments were considered as elite markers,8 alleles with positive effect were identified and considered as the elite alleles,and 10 typical materials were found car-rying these elite alleles by allele effect analysis.These results provide a great significance for candidate gene mining of yield and sucrose content traits and parents selection of hybrid combinations in sugarcane breeding.
维普
万方数据