Improvement Effect Of Corn DOM Group Backbone Lines On Non Reid Group Core Germplasm

Expanding and improving domestic germplasms has become an important way to solve the problem of homogenization of maize in China,and the introduction and improvement of foreign germplasms is an effective way to expand local germplasm at present.In this study,the core inbred line J9D207 was improved by inbred lines M5972 and Chang 7-2 of Dom group,4 improved lines were obtained.5 Reid group inbred lines,4 improved lines and 2 basic lines were used as maternal and paternal parents,respectively.30 hybrid combinations were made to study the heterosis,combining ability and correlation.The results are as follows:1.Mid-parent heterosis analysis showed that Z2(J1598×J1845)and Z3(J1072×J1845)with 90.21% and 87.06% for yield per plant,respectively.Indicating that improved line J1845 could be used in high yield combinations.2.The analysis of combining ability showed that the general combining ability(GCA)effect values of improved line J1845 were prominent in ear length(6.32),ear diameter(3.68),ear weight(9.56),100-kernel-weight(7.31)and yield per plant(7.18);The special combining ability(SCA)effect value of J1845 is also high as a paternal parent,among which J1598×J1845 and J1072×J1845 have the effect value of 6.59 and 10.19 for yield per plant and 100-kernel weight,respectively.Suggesting that J1845 has great application potential.3.Major gene + polygene genetic analysis of yield traits showed that ear length were accorded with C-0 genetic model,and were mainly controlled by major genes.Ear diameter was accorded with the E-0 genetic model and was mainly controlled by the major gene;ear weight was accorded with E-1 genetic model and are mainly controlled by multiple genes.The number of rows per ear was accorded with the E-0model and was mainly controlled by the main gene;The kernel number per row was consistent with the D-2 model and was controlled by both major genes and polygenes;The 100-kernel weight character was accorded with the E-0 genetic model,and was mainly controlled by the main gene.The cob diameter character conformed to the E-1genetic model and was mainly controlled by the main gene;The trait of ear kernel weight was accorded with the E-0 genetic model and was controlled by both major genes and polygenes.4.Ear weight and 100 kernel weight had a very significant positive correlation with yield per plant.These two characters played a key role in yield.Indicated that traits such as ear length and kernel weight should be considered first.