| A total of 13 inbred lines of sweet corn which with greet genetic diversity was used selectively as parents to make complete diallel crossing in accordance with the Griffing method 4 in order to study F1 hybrids, backcrossing generations and parental materials. Quantitative analysis of 16 main characters of waxy corn was studied as follows:heterosis analysis, broad sense heritability, narrow sense heritability, general combining ability, specific combining ability, correlation and path analysis. According to analysis, conclusions are evaluated as follows:(1) The heterosis of F1 hybrids are ubiquitous in waxy corn and the positive heterosis are higher than negative parts universally (except Rare ear length, Starch content, Stem diameter, Soluble protein content. It shows that there are some superiority combinations in the 40 Hybridized combinations which are made by 13 parent inbred lines in this experiment.The order of average value of heterosis indexes is:Grain yield> Single ear weight> Grain number per row> Soluble protein content> Corn cob weight> Ear height> Plant height> Ear length>Rare ear length>Stem diameter>Ear width>100-grain weight> Ear row number> Corn cob width >Starch content> amylopection content.(2)The order of variation coefficients of heterosis indexes is:Grain yield> Corn cob width > Grain number per row> Rare ear length> Ear length>100-grain weight> Soluble protein content> Stem diameter> Ear width>Ear height> Ear row number> Starch content> Corn cob weight> Single ear weight> amylopection content>Plant height.So in these 16 traits, Grain yield, Corn cob width, Grain number per row>,Rare ear length,Ear length have more margin to select and the margin of others are narrow.(3) Broad sense heritability from strong to weak is:Soluble protein content> Starch content> Corn cob weight> Grain yield>100-grain weight> Plant height> Single ear weight> amylopection content > Ear width> Corn cob width> Grain number per row> Ear height> Ear row number> Stem diameter> Ear length>Rare ear length.Narrow sense heritability from strong to weak is:Plant height> Grain yield> Corn cob weight> Ear width> Single ear weight> Ear height> Ear row number > Stem diameter>100-grain weight > Ear length> Rare ear length> Grain number per row> Corn cob width> amylopection content > Starch content> Soluble protein content.lt can be selected in early generations if broad sense and narrow sense heritability are both high, such as Corn cob weight, Grain yield, Plant height,Ear width, Single ear weight, Ear height,but if not, it is easy to be influenced by environment, so it is better to select in later generations, such as 100-grain weight, Rare ear length.(4) The general combining abilities of 13 parents inbred lines in 16 main traits present very significant difference and the specific combining abilities of Hybridized combinations are also present significant or very significant difference.The positive effect value of parent inbred linesJiN 203,JIN 204,JiN208 and JiN5,JiN8 are generally higher and the general combining abilities in grain yield and soluble Starch content of them are also higher. So these parent inbred lines can be used as good parents in the selection of good waxy corn..The hybrid combinations.JiN 204×JiN5,JiN208×JiN8,JiN208×JiN5 are good combinations for high yield and high quality breeding. The high yield and high quality breeding need high general combining ability in two parents or at least one parent. But it is possible that the hybrid has high specific combining ability while its two parents'general abilities are low.(5) The correlation coefficients between grain yield and main traits from strong to weak are:Single ear weight> Corn cob weight> Ear width> Plant height> Stem diameter>Ear length> Ear height> Ear row number > Grain number per row> 100-grain weight> Corn cob width > amylopection content > Starch content > Soluble protein content> Rare ear length. Single ear weight,Corn cob weight, Ear width, Plant height,Stem diameter,Ear length,Ear height,Ear row number,Grain number per row,and so on,have very significant or significant positive correlation with grain yield. In order to obtain high yield waxy corn, it must priority select them which influent grain yield most greatly. The direct path coefficients from strong to weak are:Single ear weight > Grain number per row> Ear width> Plant height> Ear row number > Ear length> 100-grain weight> Stem diameter> Ear height > Corn cob weight> Corn cob width >Rare ear length.(6) The correlation coefficients between Starch content and main traits from strong to weak are:Stem diameter> Grain number per row>Single ear weigh> amylopection content > Ear length> Ear row number> Corn cob weight> Corn cob width > Grain yield> Ear width> Plant height> 100-grain weight> Ear height> Rare ear length>Soluble protein content. Stem diameter,Ear length,Single ear weight,Ear row number, Grain number per row and so on, have very significant or significant positive correlation with Starch content。Grain yield, Soluble protein content have very significant negative correlation. The direct path coefficients from strong to weak are:Single ear weigh> Ear width> Soluble protein content> Ear row number> Plant height> Rare ear length> Grain number per row> 100-grain weight> Stem diameter> Ear height>Grain yield> Ear length>Starch content.
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