| In this experiment,there 12 Waxy corn inbred lines with large differences in performance were selected from 100 fields.The 12 Waxy maize inbred lines were subjected to cluster analysis using SSR molecular markers and 12 inbred lines were obtained.The genetic distance between the two,and according to the inbred tree of phylogenetic relationships.12 waxy maize inbred lines were classified.Then,according to the principle of incomplete double-crossing(NCII),a hybridization experiment was designed to obtain 35 hybrid combinations,and 12 combinations of inbred lines were analyzed for general combining ability.Specific combinations and average advantages were obtained for each of the 35 cross combinations.Analysis of super-parent heterosis,heterosis index,and comparison of heterosis and genetic distance;the main findings are as follows:1.A total of 36 allelic variation points were detected in 14 pairs of maize SSR core primers,ranging from 1 to 3,with an average of 2.57,and the average polymorphic information content(PIC)was 0.6122,with a range of 0.5561-0.8264.The genetic distances of 12 Waxy maize inbred lines are significantly different.The genetic distance ranged from 0.2433 to 1.0221,and the draw was only 0.5721.The two parents with the largest genetic distance are C2 and B3,the genetic distance is 0.0221,and the genetic distance is the largest.The parents were C2 and B4,and the genetic distance was 0.2433.With 0.6200 as the valve domain,12 inbred lines were divided into five groups.The first type had two inbred lines B3 and C3,and the second type is divided into two groups: Two subpopulations,including three waxy maize inbred lines,subpopulation 1 are two inbred lines B4 and C2,subpopulation 2 is B2,and the third type have two inbred lines C4 and B1.There are two inbred lines,C1 and C7.The fifth type is divided into two subgroups.Subpopulation 1 is the B5 inbred line,and subpopulation 2 is the C5 and C6 inbred lines.2.12 waxy maize inbred lines in B1,B4,C1,C2 and C4,C7 these six inbred lines of each character performance is superior to other inbred lines,can be used as the key selection object,used for breeding quality of waxy maize varieties.3.Among the 35 hybrid combinations,the seven combinations of C2×B2,C7×B4,C6×B2,C4×B3,C1×B3,C1×B1,and C3×B4 had better specific combining ability.4.In this experiment,the heterosis value of single ear weight,ear height,axis weight,rind rate,and amylose content were higher,and the heterosis of crude starch content,amylopectin content,ear row number,and baldness were longer.low.The changes of plant height,ear height,single ear weight,and axial weight were significant,and the changes were obvious.The changes of stem diameter,panicle diameter and axis rough rind rate were smaller.The average of the 15 traits of the hybrid combination was higher than that of the parental hybrid line.Among the 15 traits of hybrid combinations,the average dominance and super-parent heterosis of plant height,ear height,panicle length,row kernel number,single panicle weight were all positive,and the other traits were more positive than negative..The combination with strong average advantage are C1*B4,C2*B1,C5*B3,C5*B5,C7*B4,C7*B5,and the combination of strong parental advantages is C1*B4,C5*B3,C6*B3.,C7*B4,C7*B5,a combination of better comprehensive heterosis is C1*B4,C5*B3,C7*B4,C7*B5.The average order of heterosis was: single ear weight> ear height> axis weight> number of row grains> plant height> ear length> ear thickness> axis thickness> rind rate> amylose content> stem diameter> ear row number> crude starch content> amylopectin content> long baldness.5.Comparing the heterosis and genetic distance of the traits such as single panicle weight,rind rate,and starch content of coarse grains,we can see that the heterosis of cross combinations composed of parents from different groups is higher than that of cross combinations composed of the same group.High,indicating that the well-performing hybrid combinations are mostly composed of parents of different groups.However,there is no uniform correlation between heterosis and genetic distance. |
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