Study On The Heredity Of Main QualitativeTraits In Waxy Corn (Zea Mays L. Certina Kulesht)

The experiment and 28 hybrid combination were designed according to the Griffing diallel methodⅡby eight inbred lines of waxy corn.To aim the weakness of waxy corn breeding at present,such as pericarp thickness,bad tenderness and low nutrition content.Genetic characteristic of 7 characters were studied.The main results as following:1.The analysis of pericarp thickness and Pericarp and dregs content heterosis indicated that 54﹪and 64﹪combinations over high parents heterosis was negative,and 32﹪and 54﹪combinations over average heterosis was negative.The heterosis of amylopectin content was small,the range is also narrow,the combinations of over average heterosis and over good parents showed low ratio in total.The heterosis of protein content over parental means,high parent and low parent were all negative,this indicated that protein content of combinations were close to low parent and showed negative heterosis.Fat content consistently showed positive heterosis,the range is wide.The heterosis of fiber content and Lysine content obviously showed negative heterosis,indicated that it is impossible to improve the content of fiber and lysine by heterosis.According to the average value of heterosis index,the order showed as following:fat>pericarp thickness> Pericarp and dregs content> amylopectin> protein> lysine.>fiber.The order of variation index of heterosis index is fat> fiber> Pericarp and dregs content> protein> lysine> percarp thickness> amylopectin.2.From the synthetic evaluation about the value of general combining ability ,the results showed that N27 was the an excellent inbred line on the pericarp thickness and Pericarp and dregs content,had high quality traits in 8 inbred lines;second,the N28 was also a good inbred line,and had low fat content;N8 had higher negative value of GCA effect in pericarp thickness and Pericarp and dregs content;N23 had the highest and positive value of GCA effect in amylopectin, fat, fiber,lysine content.From the evaluation of different traits of GCA effect,the GCA effect of amylopectin were both low in 8 inbrd lines,N46 had lower GCA effect in nutrition quality traits,the GCA effect of pericarp thickness mainly showed negative.According to the synthetic evaluation about the 7 traits,N34 was the worst in 8 inbred lines.3.The result showed that there was not directly correlation between hybrid combinations SCA and GCA of parents,the analysis of total combining ability showed that the combinations decided by TCA,was not simply judged by GCA or SCA.It was shown that N4×N28 which was the best combination had thin pericarp thickness and high nutrition content.Both N4×N27,N8×N27,N28×N46 showed thin pericarp thickness and low Pericarp and dregs content; N4×N27had the high value of TCA on lysine content; N8×N27 had the high value of TCA on protein content and fat content;N28×N46 had the high value of TCA on fat content and fiber content.4. According to the result of the value of GCA effect and the analysis variance of SCA,8 inbred lines were evaluated synthetically.The result showed that N8 and N27 were outstanding inbred lines on pericarp thickness;N8 and N28 were excellent inbred lines on Pericarp and dregs content;N23 and N4 respectively had higher value of GCA effect on amylopectin and protein content,N23 and N4 were the excellent inbred lines in breeding practice.5. According to the calculating of heritability of 7 traits in 8 inbred lines.The order of the generalized heritability of all traits showed as following:pericarp thickness>Pericarp and dregs content > protein > amylopectin > fiber > lysine > fat;The order of the narrow heritability of all traits showed as following: pericarp thickness > amylopectin > protein > > Pericarp and dregs content > lysine> fiber> fat.6.The analysis of correlation of all quality traits indicated that there was very significant positive correlation between lysine and amylopectin content;very significant positive correlation was found between amylopectin and fiber;Postive significant correlation was found between amylopectin and fat content; Both fiber,protein and fat had significant positive correlation with lysine content; Significant negative correlation was found between fiber and pericarp and dregs content;Both protein and fat had significant negative correlation with pericarp thickness.7.The correlation of Over-HP heterosis and Over-MP heterosis of all quality traits were studied. Postive significant correlation existed between fiber and amylopectin content,between lysine and amylopectin content; Postive significant correlation existed between protein and lysine content; there was significant positive correlation between fiber and lysine content;The results indicated that the mutual heterosis of traits can be cooperativly used in breeding practice.8. According to the analysis of genetic correlation and path between all agronomic traits and all quality traits.The result showed as following:positive significant correlation was found between pericarp thickness and tassel length;while very significant negative correlation existed between pericarp thickness and kenernel per row;No significant correlation was found between agronomic traits and pericarp and dregs content;there was significant positive correlation between plant height and amylopectin content,between the acreage of spike leaf and amylopectin content;while negative significant correlation was found between tassel branch number and amylopectin content;there was very significant positive correlation between tassel length and amylopectin content, between ear length and amylopectin content. Negative significant correlation was found between ear row number and protein content. There was significant positive correlation between kernel per row and fat content.Positive significant correlation was found between plant height and fiber content, there was very significant positive correlation between ear length and fiber content.No significant correlation was found between agronomic traits and fiber content.