Analysis Of The Combining Ability And Heterosis Of Waxy Maizeinbredlines Of China

In the test,56 waxy maize hybrid combinations were done by using 15 waxy maize inbred lines with NC incomplete diallel cross experiment design.Using morphological markers and ⅡSSR molecular markers with 15 waxy maize inbred lines and hybrid combinations,combining ability and genetic distance analysis and clustering analysis were carried out.At the same time,middle parent hetesosis,better parent heterosis and heterosis index were analyzed.The relationship of the waxy maize genetic distance and heterosis were also studied.The main results were as follows.1.15 servings of waxy maize inbred lines of genetic distance is between 0.3125 ~ 0.9201,with a mean of 0.6163.B2 and genetic distance between A3 is the largest,0.9201;B4 and A1 genetic distance minimum,only 0.3125.On the basis of genetic distance 0.645 to 15 waxy maize inbred lines was divided into six groups.The first class is divided into two subgroups,including four glutinous corn,one with A1,B2,and subgroup two including B1 B7.The second type has A4 and B3.The third group consists of three glutinous corn,including B6,subgroup 2 including A2 A5.The fourth subgroup consists of three glutinous corn,including A6,subgroup 2,and B4 B8.The fifth category,A3 and A5,are made of glutinous corn;The sixth class has A7,which is a kind of glutinous corn.2.The general combining ability better inbred lines were B2,B4,B5,B6,A1,A3,A4,A5;Special combining ability better hybrid combination is B5 * A3 A1 * B2 and B6 * A5,A3 * B4,B5 * A5 and A4 *B3,B5 * A3,A5 *B3.3.Research has shown that,axle load,and variations in grain number and other traits,and heterosis index is larger,and the stem diameter,the head,shaft,a higher character of change in small,hybrid combination various characters were superior to the average of inbred lines,spikelets and the hybrid combinations and row grain number is bigger than the average and variation parent.Heterosis is widespread in the filial generation,and both the average advantage and transgressive advantage,there is the phenomenon of positive excess negative advantages,shows that this experiment by 15 inbred lines are equipping 56 of hybrid combinations,there are a number of advantages,B2*A3,B6 * A5,A3 * B4,B5 *A4 combined in 15 characters with strong heterosis,the characters and average size of heterosis index: : weight per ear > axle load line > grain number > ear length > ear position > length > bald tip skin residue rate > spike thick > stem diameter > the even starch of total starch content > shaft rough > ear row number > crude starch content > plant height > amylose of total starch content.Spikelets instructions,axle load and line grain number and ear length and other traits in breeding work option is bigger,plant height,amylose of total starch content and character of crude starch content of heterosis index is lower,the choice is relatively small.4.Waxy maize hybrid combinations 15 character difference between the combination of all reached very significant level,there is real can be caused by genotype genetic differences Waxy maize hybrid combinations from different groups of parents spikelets its and amylopectin starch total heterosis index is larger,the opposite is smaller strong heterosis combination most parents are from different groups,and the genetic distance is larger;Weak heterosis combination of parent most smaller genetic distance or from the same group,and genetic distance between waxy maize inbred lines and is not a simple linear relationship.