| The comprehensive evaluation of tomato germplasm resources and hybrid combinations,as well as the analysis of the genetic effects of self-inbreeding quantitative traits are the scientific basis for the rational breeding of tomato breeding and hybrid combinations.This study is divided into three parts.The first part is based on 34 phenotypic traits to conduct genetic diversity analysis,correlation analysis,principal component analysis,cluster analysis and comprehensive evaluation on the 400 tomato germplasm resources collected;In part,the 30 phenotypic traits of the 529 tomato hybrid combinations that were assembled in the previous period were described and statistically analyzed.A combination evaluation method of principal component analysis and membership function was used to construct a comprehensive evaluation function of tomato hybrid combinations,and 10 better combinations were selected;The third part uses 20 tomato inbred lines(16 female parents and 4 male parents)as materials,using incomplete two-row hybridization method,prepared 64 hybrid combinations,and carried out quantitative traits on 11 fruits The analysis of combining ability and heritability has screened out the superior parents and combinations.The main findings are as follows:1.The genetic diversity index of quality traits of 400 tomato germplasm resources ranged from 0.30 to 1.26,the largest was growth potential;the genetic diversity index of quantitative traits varied from 1.63 to 2.08,and the largest was leaf length And leaf width;the largest coefficient of variation is the single fruit weight,which is 55.21%.Most of the quantitative traits are extremely significantly related.The cumulative contribution rate of the five extracted principal components reached 71.59%.Cluster analysis clusters materials into class VI,and the materials in the same group have great similarity.A comprehensive evaluation of the phenotypic traits of the tomato materials tested,of which the number D(0.808)of the tomato comprehensive evaluation No.16 was the highest,and the comprehensive traits were the most excellent.Combined with the results of cluster analysis,the tomato numbered 172 in group I,the tomato numbered 287 in group II,the tomato numbered 293 in group III,and the tomato numbered 275 in group V were selected.Tomato number 32 in group VI is the most outstanding representative material in each group.2.The 30 phenotypic traits of 529 tomato hybrid combinations have rich genetic variation,which provides a theoretical basis for the breeding of improved varieties.The coefficient of variation of 9 botanical traits ranges from 6.11%to 41.90%,the largest is ripeness,and the smallest is leaf vein color;the coefficient of variation of 21 fruit traits is 6.51%to 41.22%,and the largest is the shape of the fruit top The smallest is the longitudinal diameter of the fruit.On the basis of rich material variation,a combination of principal component analysis and membership function is used to comprehensively evaluate tomato hybrid combinations,and the top 10 hybrid combinations with the best overall performance are ranked in the order of ZJ093,ZJ075,ZJ492,ZJ118.,ZJ487,ZJ094,ZJ494,ZJ355,ZJ496,ZJ414.3.16 female parents and 4 male parents are combined into 64 cross combinations.The environmental variance of single fruit weight is large,and it is greatly affected by the environment;the variance of the general combining force and the special combining force of the size of the fruit stem pits are not much different,which are 51.39%and 48.61%,respectively.Under common control,the special combining ability of other traits is larger than the general combining ability,which is controlled by the non-additive effect Heritability analysis showed that the general heritability and the narrow sense heritability of fruit stem pit size were higher and less affected by the environment.60435×62187,60370×62188,60400×62315,60370×62329 have higher relative effect value of special combining ability;according to the relative effect value of general combining ability,the comprehensive evaluation of 20 parents using reverse ranking scoring method,and finally get Out of 16 female parents,the scores from high to low are 60425,60417,60232,60433,60312,60370,60399,60435,60167,60400,60203,60401,60440,60143,60142,60139;4 male parents score from The order from high to low is 62315,62188,62187,62329.The above research results provide an important theoretical basis for the future selection of new tomato varieties in Ningxia and the rational preparation of hybrid combinations,which lay the foundation for future production and breeding. |
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