Study On The Genetic Effects Of Maize Inbred Lines With Non-Reid Population

Germplasm resources is an important basis for maize breeding.Introducing and improving foreign germplasm is one of the ways to broaden the germplasm resources,and an important approach to address the narrowed maize germplasm resource base in northern China.To improve or continue to improve the improvement of exotic germplasm,in order to create new and excellent germplasm.Based on the characteristics of the Non-Reid group backbone inbred lines PH4CV and PHB1M,a basic population was established and DH breeding techniques were used to carry out genetic improvement and further improvement.Firstly,PH4CV and PHB1M were used as the basic materials to carry out the first round of improvement and bred J9D207 and J1577.Then,J9D207 and J1577 were used as materials for the second round of improved bred J1633 and J1881.Then,the third round of improvement was performed using J1633 and J1881 as materials.Bred J1628,J1630.Analyze the effects of different rounds of improvement.In this paper,based on the species and improved lines as male parent,Reid group of inbred lines as female parent with incomplete diallel crosses.The genetic gain,Heterosis and combining ability of study on improvement effect of different cycles were analyzed,providing reference for the introduction of maize genetic improvement.The results of the test are as follows:?1?The average yield per plant of the Non-Reid group increased by 14.11%,23.0%and28.70%compared with the basic line,and both the improved lines and the basic lines reached extremely significant levels.The average yield of J1628 per plant in the C3 round increased highest.This indicated that the continuous genetic improvement of Non-Reid group backbone strains by DH breeding technology was effective in improving yield per plant.?2?In the three-round improvement of C1-C3,the improvement of ear number was significant,but hundred-grain weight had no significant effect.The row number and spike length C1 round J1577 improved the effect;the C2 round stem rough improved effect was good.It was seen that there are effects on the continuous genetic improvement of multiple traits based on DH breeding techniques.?3?Both the improved lines and the stem lines had significant heterosis in all rounds.The heterosis of C1-C3 per plant with PH6WC as the female parent was higher than that of C0;the heterosis of C₂ and C₃ with 3D108 as the female parent was high.In C₀,the C₂ and C₃ rounds with 2VK as the parent are higher than the C0 round,but the C1 round is lower than the C0 round.?4?In terms of general combining ability,GCA of single plant yield and hundred-grain weight of improved line J9D207 was higher than that of basic line;GCA of single plant yield,hundred-grain weight of round improved line of J1633 was positive,C₃ round improved line The yields of single plants such as J1630 and J1628 and the hundred-grain weight were positive,and the plant height and baldness were negative.It was considered that the improvement effect of the C₃ round improved lines J1630 and J1628GCA was good.?5?The yield per plant of SCA,C₁-C₃ except for the cross combination with the PH2VK backbone,was higher than that of the C₀ with other backbones,with J1495×C₁,M54×C₂,PH6WC×C₃,PHGJ4×C₂,3D108×C₂ is the highest.