Research On Heterosis、Genetic Effects And Correlation In Characters Of Hybridization Generation Of Tomato

Take5female parent self-bred lines、8male parent self-bred lines and the40cross combinations which were obtained from hybridizing with5female and8male parents, adopting NCII design. Study the heterosis and genetic effects of plant style、 yield、 early maturity and quality characters containing27characters in all, and correlation analysis and path analysis were conducted among the characters and the optimal parents and cross combinations were screened out. The results showed as follow:1Heterosis showed diversity in different character. Most characters expressed between high value parent and low value parent, some characters were prefered assocation with low value parent, and prefered assocation with high value parent. Fruit hardness was prefered assocation with low value parent. Indexes of fruit shape、 soluble solid、 soluble sugar、 total sugar、 reducing sugar and sugar acid ratio、Vc and lycopene ranged between high value parent and low value parent; and total acid and pH value leaned to mid parent values.2Some parents showed superior general combining ability, which were DiD4, Dal07, A4, Hongfu, Heishi and Niufanqie. Some parents exhibited superior special combining ability, including DiD4, Dal07,19, Hongkunlun, A4, Dongsan and Niufanqie.3Vc was significantly correlated with initial time of flowering、 fruit setting stage、 stem diameter、 leaf width and the fruit number per plant; the correlation coefficients were0.29、0.29、0.28and0.30respectively. Lycopene was very significantly correlated with the first inflorescence site, and the correlation coefficient was0.37. Soluble solid was significantly correlated with plant hight and node number, and the correlation coefficients were0.30and0.35respectively. The correlation coefficient of indexes of fruit shape and fruit hardness was 0.48, which showed significant level. Fruit hardness was significantly correlated with total acid and pH value, whose correlation coefficients were0.30and0.40respectively. Soluble solid was significantly correlated with soluble sugar、 total sugar and sugar acid ratio, and the correlation coefficients were0.31、0.44and0.36, respectively. The correlation coefficient was0.54between total acid and pH value.4The initial time of flowering、 fruit setting stage and the date of first harvest very significantly correlated with each other. The direct effect of initial time of flowering to the date of first harvest was0.3519, and that of fruit setting stage to the date of first harvest was0.4136. The direct effect of pH value to fruit hardness was0.3217, and the indirect effect was less via indexes of fruit shape. The direct effect of indexes of fruit shape to fruit hardness was significant, up to0.4188. The direct effect of pH value to soluble solid was0.2982, and the indirect effect was minus effect. There was minus direct effect between fruit hardness and soluble solid. The direct effect of total acid、 pH value and reducing sugar to sugar acid ratio were minus effect; and the indirect effect of total acid to sugar acid ratio via pH value and reducing sugar was minus too. The direct effect of the date of first harvest and sugar acid ratio to soluble solid was positive effect, and the direct effect of fruit setting stage、 fruit number per plant and fruit weight to Vc was positive effect too. Because the direct and indirect effect of fruit setting stage to Vc worked together, the correlation between fruit setting stage and Vc reached to be significant level. The same was happened between the node number and sugar acid ratio.5Base on the characters parameters, the superior cross combinations were shown as follow:DiD4×12、 DiD4×Heish、 Da107×12、 Hongli×Hongfu, Hongli×A4. Da107×Hongkunlun、Da107×Heish、 Da137×Hongkunlun. Da137×Hongfu、 Hongli×Heishi、 DiD4X Niufanqie and T4X Niufanqie.