Study on the heredity of pericarp thickness and amylopectin _content traits in fresh-eatable waxy corn | 鲜食型糯玉米果皮厚度和支链淀粉含量的遗传特性

Chinese. 研究鲜食型糯玉米果皮厚度和支链淀粉含量的遗传特性，为选育优质、高产的鲜食糯玉米品种提供理论依据。采用Griffing双列杂交法Ⅳ，以8个糯玉米亲本为研究对象，对其果皮厚度和支链淀粉含量的遗传特性进行了系统分析。糯玉米果皮厚度表现出一定的负向超亲优势，支链淀粉含量的杂种优势较弱，表现近低亲遗传；糯玉米果皮厚度和支链淀粉含量的变异既有加性基因作用，也有非加性基因作用；8个糯玉米亲本果皮厚度的GCA值大小为N7N23N34N46N28N4N8N27，支链淀粉含量的GCA值大小为N23N7N28_N27N34N8N4N46；果皮厚度的广义遗传力较高(90.53%)，果皮厚度和支链淀粉含量的狭义遗传力均较低；N8、N27是选育薄皮糯玉米的理想亲本，N23是选育高支链淀粉含量糯玉米的理想亲本。相关性及通径分析结果表明，果皮厚度与雄穗长呈显著正相关,与行粒数呈极显著负相关；支链淀粉含量与株高、穗位叶面积呈显著正相关，与雄穗长、穗长呈极显著正相关，与雄穗分支数呈显著负相关。利用杂种优势可以选育果皮较薄的糯玉米杂交组合；通过分析亲本和组合的配合力效应及方差，可以对糯玉米自交系的利用价值进行评价；果皮厚度和支链淀粉含量与部分农艺性状相关性显著，可以提高糯玉米品质育种的效率。

English. The aim of this study is to research the heredity character of pericarp thickness and amylopectin content in fresh-eatable waxy corn. A synthetical heredity analysis was provided for pericarp thickness and amylopectin content based on the Griffing diallel design for 8 inbred lines of waxy corn. The analysis of pericarp thickness and amylopectin content heterosis indicated that some of the hybrized combinations expressed negative over high parents; The heterosis of amylopectin content was small and close to low parent. The inheritance of pericarp thickness trait and amylopectin content was controlled by additive genes, and affected by non-additive genes as well; the order of pericarp thickness GCA value was: N7N23N34N46N28N4N8N27, and the order of amylopectin GCA value was: N23N7N28N27N34N8N4N46. The generalized heritability of pericarp thickness was higher than amylopectin content. Both the pericarp thickness and amylopectin content showed low narrow heritability. N8 and N27 were the excellent inbred lines on the pericarp thickness, and N23 was the excellent parent on the amylopectin content in breeding practice, according to the analysis of correlation and path between agronomic traits and these two traits. The result showed as following:positive significant correlation was found between pericarp thickness and tassel length; while extremely significant negative correlation existed between pericarp thickness and kenernel per row; 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 extremely significant positive correlation between tassel length and amylopectin content, between ear length and amylopectin content. Pericarp thickness can be reduced by utilizing heterosis. According to analysis of combining ability and variance analysis of parents and combinations, the utilization value of the inbreds was synthetically evaluated. Furthermore, there was significant correlation between some agronomic traits and these two traits. It will promote the efficiency of quality breeding in waxy corn.