Analysis of combining ability on biomass yield and plant characters for silage maize.

Nine inbred maize lines were combined to 36 combinations by Griffing 4 diallel cross model,and the combing ability of biomass yield and plant characters at dough stage were analyzed by complete randomized block design in field.The results showed that the general combining ability of biomass yield for Nan 60-1 was the highest in all combinations,then M9 and CML161,and these inbred lines was tropical line.The special combining ability of the combinations CML161×P42c9MH4-1-2-2-B-1-1,M9 × Ye 478,Nan 60-1×P44c10MH17-32-2-B-3-2 were better and according with the cross model such as tropical line × subtropical line or tropical line × temperate line.The correlation and heritability analysis of special combining ability for all characters indicated that the correlations between biomass yield and plant height,stalk diameter,area of ear leaves,and nodes were obvious,and the narrow heritability of ear height,plant height,nodes and green leaves below ear was higher.Therefore,the main selection of characters for inbred lines should be plant height and nodes,then green leaves below ear,and the effect of direct selection on biomass yield was lower.