Breeding Potential Analysis Of Some New Maize Inbred Lines

In this study, the material were 16 new maize inbred lines which be difference in kernel length and size of Maize Research Institute of Sichuan Agriculture University and 4 elite inbred lines in Sichuan and 190 crosses combined by 20 inbred lines. 20 inbred lines were studied by agronomic and economic trails observation analysis and cluster analysis based on SSRs. 190 crosses were studied by agronomic and economic trails observation analysis and combing ability analysis based on 4th method of Griffing's. Meanwhile the genetic character of kernel length & kernel width & kernel depth & HKWI were studied. The main results as following:1 .Inbred lines variance of plant height, ear height, ear length, sterile length, rows per ear, kernels per row, plant yield, 100-kernel weight and kernel length of 20 inbred lines were significant at 0.01 level. The comprehensive of plant yield and other trails contributing to plant yield were synthetic analyzed. The results indicated that inbred line R08,5073₂,5041₃,5289₁,5024₂,ES40 ,18₅99 had better comprehensive of agronomic and economic trails. Crosses variance of plant height, ear height, interval between anther and silk, ear length, sterile length, rows per ear, kernels per row, kernel per ear, 100-kernel weight, unit weight, shelling percentage, ear weight, axis weight, plant yield, HKWI, kernel length, kernel width, kernel depth were significant at 0.01 level. The plant yield of 10 and 6 crosses was more than Chuandanl3 and Chuandan21, which were check variety.2.GCA and SCA variance of plant height, ear height, interval between anther and silk, ear length, sterile length, rows per ear, kernels per row, kernel per ear, 100-kernel weight, unit weight, shelling percentage, ear weight, axis weight, plant yield, HKWI, kernel length, kernel width, kernel depth were significant at 0.01 level. Inbred line 4097₂, R08,5024₂, 5220₂, ES40, 4022₁ had better comprehensive GCA of plant yield and other trails contributing to plant yield. Hybrids number of SCA positive and negative effect significance at 0.05 or 0.01 level were 52 and 41. 5289₁ 5064₂ had highest plant yield SCA and 5073₂x698₃ had the lowest one. Variance of plant yield SCA ranged from 93.70 to 324.34, and inbred line 5227₂,4146,R08 had smaller variance, and inbred line 5064₂,5073₂,5253₃ had larger variance. 17 crosses were combined by 4097₂ or 5024₂ in 30 crosses which had larger total combing ability(TCA) of plant yield. So the results indicated that inbred line 4097₂ and 5024₂ performed better judged by high plant yield GCA and wide variance range of plant yield SCA, and high plant yield crosses could probably be screened from crosses combined by the two inbred lines, but inbred 4097₂ had a lower plant yield, so it should be male parentage in crosses. Other inbred lines had their own advantages and could be used in different breedingaims.3.Genetic distances (GD) of 20 inbred lines were calculated based SSR analysis data. Although average GD (0.82) was smaller, wider GD range (from 0.11 to 1.26) showed, to some extent, higher genetic morphology among studied materials. In this cluster result, 20 inbred lines were classified 4 groups: group I included B73 and Mol7, so this group should be deuterogenic group of group Reid and Lancaster. In subgroup 1-1, inbred line 698₃,5073₂,3237,5227₂,5024₂,5129₁ got together with B73, these inbred lines should be modified group Reid. In subgroup 1-4, inbred line 200B and R08 got together with Mo 17. These two inbred lines should be subgroup Lancaster. In subgroup 1-2 and 1-3 and II, there were no inbred lines got together with typical inbred line, so subgroup 1-2 and 1-3 and II should be other group. Group III include Huangzao4, so this group should be group Sipingtou. Group IV include Dan340, so this group should be group Ludahonggu. Meanwhile the cluster result also indicated that group I include 12 inbred lines of 16 new inbred lines, In some extent, it indicated that the germplasm of these new inbred lines for studying was limited.4.According to pla...