Analyses Of Breeding Potential For Twenty New Maize Inbred Lines

Elite inbred lines are important basis to breeding maize hybrid.Comprehensive evaluation of inbred lines agronomic and economic trait and combining ability effect is the key to breed an elite inbred line.Therefore,in this study,we prepared 100 combinations by 20 new inbred lines and five elite inbred lines according to NC ?,study the main traits,combining ability effect and yield heterosis,in order to clear the breed applied value of the new lines,then use them for breed practice.The main results were as followed:1.The combining ability effect showed,the yield per plant GCA effect of eight new lines such as 14TK22061131,14TK22032111 and 14TK22143657,etc,were positive significantly or extremely significantly,could be the parent to breed high yield hybrid.Plant height GCA effect of seven new lines such as 14TK22074343,14TK221312 and 14TK22102811,etc,were negative extremely significantly,could be the parent to breed dwarf hybrid.The ear length GCA effect of five new lines such as 14TK22012511,14TK22032111 and14TK22202515,etc,were positive significantly or extremely significantly,could be the parent to increase the ear length of cross combinations.The ear rows GCA effect of six new lines such as 14TK22127621?14TK22093121 and 14TK22202515,etc,were positive extremely significantly,could be parent to add the ear rows of cross combinations.The 100-kernel weight GCA effect of 5 new lines such as 14TK22143657,14TK2212521 and 14TK22012511,etc,were positive significantly or extremely significantly,could be the parent to increase the1000-kernel weight of cross combination.The SCA effect of yield per plant,ear diameter,row kernel,100-kernel weight and kernel rate of combination 41×14TK22061131 were positively,especially,the SCA effect of yield per plant and ear diameter were most positively,the bare tip length SCA was negatively,yield and yield characters were excellent.2.Yield heterosis indicated that.Compare to control,the yield standard heterosis of combinations TKS211×14TK22202515,41×14TK22061131,41×14TK221312,TKS211×14TK22093121 and kws-51122×14TK22061131 were more than 10.14%,9.53%,8.96%,7.3% and 5.15%,respectively,at Tieling.The combinations 41×14TK22193214,41×14TK221612,41×14TK22061131 were more than 40.26%,22.92%,20.06%,respectively,at Zhengzhou.In a comprehensive view of the two place,standard heterosis of yield per plant of 41×14TK22061131,14TK222211×L14TK22032111,TKS211×14TK22202515 and14TK222211×14TK221436 were over 5%.The average value were 14.80%,9.29%,7.95%and 5.33%,respectively,41×14TK22061131 had the higher standard heterosis at the both place.3.The comprehensive performance of the agronomic economic character of the new elite inbred lines showed,the yield per plant of 14TK221312,14TK22102811 and 14TK221521 were higher;plant and ear height of 14TK22102811 and 14TK221312 were dwarf;ear length of 14TK22102811 was longest;100-kernel weight of 14TK22093121?14TK22046131?14TK22102811?14TK221521?14TK22143657 and 14TK22084415 were higher,the average value was over 35g;kernel rate of 14TK22116132 and 14TK221312 were over 89%.Comprehensively,the yield per plant of 14TK221312 and 14TK22102811 were higher and the other economic characteristics were also preferably,that indicated,the two new lines had goodness self-characteristics,oppositely,the new lines 14TK22202515 and 14TK22032111 were poorer,the other lines were common.4.Genetic cluster analysis showed,the rate of the first eight principal component contribute to total variation achieved 89.36%,the amplitude of genetic distance among the inbred lines was 0.469-36.486,the average value was 13.696.Take the genetic distance 22 as the standard,the 25 inbred line could be divided into five class,the first class included 15 inbred lines,as 14TK22012511,14TK22046131,14TK22061131,14TK22074343,14TK22116132,14TK221312,14TK22143657,14TK221612,14TK22172213,14TK22182251,14TK22193214,14TK22202515,K169,KWS-51122,14TK222211.The second class included 14TK22032111 and TKS211.The third class included five inbred lines,such as 14TK22023224,14TK22053214,14TK22084415,14TK22093121,14TK22127621.The fourth class had only 41 inbred line.The fifth class include 14TK22102811 and14TK221521.In conclusion,the characters of inbred line 14TK22061131 are good,the GCA of yield per plant,ear diameter and row kernel were positive,the average yield heterosis of combination 41×14TK22061131 was the highest at both place,that indicate,the inbred line41×14TK22061131 could be used as parent to breed high yield hybrids.