| Abstract:The key bottleneck in rapeseed industryis to urgently optimize plant type and increase yield.In this study,a total of 130 elite B.napus accessions were studied,ten plant-type traits and five yield traits were investigated in the field.The phenotypic correlation analysis,path analysis,and principal component analysis were used to reveal the relationship between the plant type,yield and yield related traits for identifing the main determinant of yield per plant in B.napus.The results showed that abundant variations of plant type and yield traits were in 130 tested accessions,the order of the variation coefficient of the fifteen traits was: number of secondary branches>yield per plant>silique number per plant>first valid branch height>top branch angle>effective number of main inflorescences >number of seeds per silique=basal branch angle>the numbers of valid branch>middle branch angle=main inflorescence length>thousand-seed mass>silique length>silique width>plant height.Correlation analysis showed that significant correlations among the most of the 15 traits,silique number per plant and the yield per plant of yield traits were the highest (0.834).Among plant type traits,plant height (0.326),the numbers of valid branch (0.333),number of secondary branches (0.382),and silique width(0.208) were closely related to the yield per plant.Path analysis showed that silique number per plant (0.786) of yield traits,plant height (0.021) and the top branch angle (0.021) of plant type traits had the most direct positive effect on the yield per plant in rapeseed.Plant height,number of primary branches,number of secondary branches,top branch angle and basal branch angle had significantly indirect effect on yield per plant through the number of pods per plant.A total of six principal components were obtained by principal component analysis,including branch angle,silique number per plant,plant height,main inflorescence,silique width,and silique length factor.The tested accessions were divided into four groups according to the comprehensive evaluation of principal components,of which twelve accessions had good comprehensive properties,this had a certain reference for breeders to improve plant type in B.napus. |
