Study On The Hereditary Law Of Main Characters Of Waxy Corn

A total of twelve varieties and lines of waxy corn which,with great genetic diversity was used selectively as parents to make incomplete out diallel crossing in accordance in order to study the inherence of yield and main characters of waxy corn.36 combinations were made in 2006.The combinations and twelve varieties were planted at experimental plot of Jilin agricultural university scince 2007.Quantitative analysis of twelve main characters(including yield) of waxy corn was studied as follows:heterosis analysis,analysis of the general combining ability and the specific combining ability,between different type of combining ability and expression of F₁ hybrid,heritability analysis of yield and main characters.According to above analysis parents and societies were evaluated as follow:(1)Heterosis:The analysis the trend of heterosis indicates,there are higher positive heterosis in heterosis and heterobeltiosis,so it shows that among these thirty-six combinations it exists some superior combinations.L3×L12,L3×L9,L4×L12,L4×L7,L6×L12,L2×L8,L2×L10,L3×L9,L6×L10,L6×L8,L3×L11,L1×L12 have higher heterosis in the twelve main characters than the other combination.It is known from the average value of heterosis index that grain yield have the strongest heterosis,then Ear height＞100-grain weight＞Grain number per row＞Plant height＞Ear width＞Ear length＞Stem diameter＞Fat content＞Ear row number＞Starch content＞Rare ear length。The order of variation index of heterosis index is Grain yield＞Rare ear length＞Ear height＞Grain number per row＞Starch content＞100-grain weight＞Ear row number＞Fat content＞Stem diameter＞Plant height＞Ear width＞Ear length.So in these twelve characters,grain yeild,ear height,Grain number per row,Starch content,100-grain weight have more wild margin to choose and the margin of other characters is narrow.(2)General combing ability:The result of the general combining ability analysis indicated that the variation caused among cross combination in twelve traits was caused by additive effect and the nonadditive effect.The variety of L6,L10,L11 and L12 was superior to other varieties in general combining ability.These four varieties can be used as good parent for cross breeding of waxy corn.(3)Specific combining ability:The result of specific combining ability analysis showed that specific combining ability of 52.78%combinations was positive,the nice societies were L4×L10,L3×L9,L6×L8,L4×L12,L2×L10,L2×L12 with higher and positive specific combining ability.(4)Analysis of total combining ability:The correlation of specific combining ability and total combining ability with yield was very significance and the two combining ability of ten main agronomic characters was consistent with yield expression of F1 hybrids,but specific combining ability was more important.So,the expression of yield was to be predicted from the utilization of the specific and total effect of combining ability. (5)Heritability:The range genetic determinative degree often main agronomic characters from strong to weak was Starch content>Rare ear length>Fat content>100-grain weight > Ear height> Plant height > Ear width > Grain yield > Ear length > Ear row number > Stem diameter > Grain number per row.Heritability was Ear height > Plant height > Ear width > Rare ear length > Starch content >100-grain weight > Ear length > Grain yield >Ear row number > Fat content> Grain number per row >Stem diameter.(6)Analysis of correlation:The correlation of genotype between grain yield and the main agronomic characters was all very significance except the Ear row number starch Content,and Rare ear length have negative correlation to grain yield.(7)Path analysis:The contribution of characters to yield was different,the contribution from strong to weak was Grain number per row>100-grain weight > Ear row number> Ear width> Ear height > Plant height > Fat content> Stem diameter > Stem diameter> Ear length> Rare ear length.So in order to improve yield, we should choose the parents which have better performance in Grain number per row,100-grain weight,Ear row number,Ear width.(8)Good combinations:Through the female general combining ability,specific combining ability and total combining ability analysed it can summed L4×L10,L3×L9,L6×L8,L4×L12,L2×L10 were good combinations in the selection of high yield variety.