糯玉米淀粉RVA黏度性状配合力与杂种优势分析

The Analysis of Combining Ability and Heterosis in Starch RVA Viscosity Traits of Waxy Maize

蒸煮食味品质是评价鲜食糯玉米品种优劣的核心指标。为探究糯玉米蒸煮品质性状的配合力、杂种优势及与亲本遗传距离关系,本研究选用55个糯玉米自交系,采用NCⅡ设计组配的156个杂交组合,研究其快速黏度分析(RVA)特征谱配合力效应并结合单核苷酸多态性(SNP)标记,分析遗传距离与杂种优势、配合力的相关性。结果表明,在被测自交系中,ZFF、XH55和NFHH一般配合力效应较高,利用其组配的杂交组合峰值黏度也普遍较高,说明利用这3个自交系组配杂交组合后代产生优势杂交种的潜力较大。相关性分析结果发现,SNP分子标记遗传距离与RVA黏度性状杂种优势显著相关,但相关系数普遍偏低(0.162~0.345),说明遗传距离对糯玉米杂交组合RVA黏度性状的预测具有一定的价值,但遗传距离与F1黏度性状之间的相关程度不足以准确预测杂种优势。另外,亲本的总配合力和特殊配合力与杂种优势显著相关,决定系数也较高,变幅在-0.781~0.830和-0.662~0.786。结果表明,在预测糯玉米黏度性状的杂种优势时,不能只依靠遗传距离,还应重点考虑亲本的配合力。本研究为后续优质糯玉米品种选育提供了亲本以及杂交组配的理论依据,从而为进一步提高优良食味品质糯玉米杂交选育的效率提供了参考。

Cooking and eating quality is the core index that determines the value of waxy maize.Studying the heterosis,combining ability and genetic distance(GD)of cooking and eating quality for waxy maize could provide theoretical references for germplasm improvement and hybrid breeding of waxy maize.In the study,55 inbred lines were used to make up 156 hybrid combinations with NC II design to analysis the combining ability of RVA(rapid viscosity analyzer)viscosity traits and explore correlations between combining ability,heterosis and genetic distance by single nucleotide polymorphism(SNP).The results showed that the general combining ability(GCA)of inbred lines ZFF,XH55 and NFHH were higher,and the peak viscosity of combinations generated by these elite lines were also higher,which suggested that using these lines may easily produce superior combinations.Correlation analysis showed that a significant correlation between GD and heterosis of starch RVA traits was detected,but the correlation coefficient was relatively lower(0.162-0.345).The result indicated that GD had a certain value for heterosis prediction,but it was not enough to correctly estimate heterosis combination in view of the lower correlation coefficient.Moreover,the total combining ability and SCA were significantly related to heterosis,and the correlation coefficient was-0.781-0.830 and-0.662-0.786,respectively.These results suggested that heterosis prediction of starch RVA traits cannot merely rely on GD,and combining ability should be taken into consideration.This study not only provides a theoretical basis for germplasm selection and combination cross of superior waxy maize in the subsequent breeding program,but also increases the matching efficiency of waxy maize cultivars with superior cooking and eating quality.