Analysis Of Combining Ability And Genetic Parameters On Yield Traits And Nutrition Ingredients Of Maize Inbred Lines

12 popular maize inbred lines were chosen to check combining ability and genetic parameters and correlation analysis of related yield characters and nutrition ingredients. Results are as follow:1) Regarding general combining ability (GCA) of any yield character, GCA is remarkablly different among different lines; For any line, GCA is remarkablly different among different yield traits.2) Regarding special combining ability (SCA) of any yield trait, SCA is remarkablly different among different hybrid crosses; For any hybrid, SCA is remarkablly different among different yield characters. The range of SCA of net yield per plot is -1.423—0.998. Two crosses (Jinhuang96B X 87-1) and (P138Xjinhuang96B) are more higher than others; Two crosses (Qi319×87-1) 和 (Zi330× Jinhuang96B) are remarkably lower than others. SCA between lines seems independent from GCA of lines and relation between them seems complex. It's very difficult to estimate SCA of the hybrid from GCA of its parents.3) Non-additive effect plays an important role in ear length, effective ear length, yield per plot, net yield per plot and row of ear. We should be less strict when we choose parents for these characters. But additive effect plays an important role in plant height, ear length, one thousand kernels weight, number per row and ear width.4) Narrow heritabilities of rows per ear, plant height and one thousand kernels weight are high. These characters can be choosen in early generation. Narrow heritabilities of rows per ear and plant height are higer than 50%.5) Genaral effect of combining ability (Tij=GCAi+GCAj+SCAij) can be used to evaluate hybrid crosses, the three highest are Jinhuang96B × 87-1, P138 × Jinhuang 96B and Zi330 × 87-1.6) Reciprocal combination effect of oil, starch and protein content are extremly remarkable, indicating there are remarkable difference in nutritional content between maternal and paternal Plant.7) Additive effect is most important in inherit of oil, protein and starch content.8) The correlation parameter between one thousand kernels weight and many other yield characters is negative. So, yield can not be improved by improving one thousand kernels weight.9) Yield improvement requires all related yield characters be improved. Net yield per plot is positive correlation with all yield characters except one thousand kernels weight. So, improving all these characters is useful to increase the yield. The correlation parameters between net yield per plot and ear length, ear width and rows of ear are higer than others. So improving these characters can be helpful to increase the yield.