花椰菜“坐球高度”性状的主基因+多基因遗传分析

Major gene plus polygene inheritance analysis of curd sitting height in cauliflower

“坐球高度”是评价花椰菜品种是否适合机械化采收的重要农艺性状之一。为了解析花椰菜“坐球高度”性状的遗传规律,使用早熟、紧实型花椰菜F 7代自交系ZAASC4101与芥蓝F_(6)代自交系ZAASJ1401为亲本构建了包括P_(1)、P_(2)、F_(1)、F_(2)、B_(1)、B_(2)的6个联合世代群体,利用主茎高度(六世代群体)和叶痕间距(F_(2)群体)两个指标来锚定“坐球高度”性状。研究结果表明,F_(2)群体中主茎高度与叶痕间距数值呈极显著相关(相关系数为0.652),并且这两个指标均为连续性的近似正态分布,符合数量遗传的特征;主茎高度的六世代群体遗传分析和叶痕间距的F_(2)群体遗传分析结果均表明,花椰菜“坐球高度”性状的最适遗传模型为:两对加性显性上位性主基因+加性显性上位性多基因遗传模型,表明该性状主要受两对主基因+多个微效基因的控制,并且遗传率达到97.84%。因此,可以利用连锁分子标记在早期世代对花椰菜“坐球高度”性状进行辅助选择和遗传改良。综上,本研究结果为进一步定位和挖掘控制花椰菜“坐球高度”性状的关键基因,最终利用生物技术手段育成适宜机械化采收的花椰菜新品种奠定了前期研究基础。

The“curd sitting height”is one of the important agronomic traits for evaluating the suitability of cauliflower varieties for mechanized harvesting.In order to analyze the genetic pattern of the“curd sitting height”trait in cauliflower,the F 7 inbred line of cauliflower(ZAASC4101,early-maturing and compact type)and the F_(6) inbred line of Chinese kale(ZAASJ1401)were used as parents to construct six combined populations including P_(1),P_(2),F_(1),F_(2),B_(1) and B_(2).The“curd sitting height”trait was anchored using two indicators:main stem height and leaf scar spacing.The results of this study showed that there was a significant correlation between the main stem height and the leaf scar spacing in the F_(2) population(the correlation coefficient was 0.652).And the two indicators were both continuous and approximately normal distribution,which was consistent with the characteristics of quantitative inheritance.The genetic analysis of the six-generation populations for the main stem height and the F_(2) population for the leaf scar spacing both showed that the optimal genetic model of“curd sitting height”trait in cauliflower was two pairs of additive-dominance-epistatic major genes+additive-dominance-epistatic polygenes genetic model,indicating that this trait was mainly controlled by two pairs of major genes+multiple minor genes,and the heritability reached 97.84%.Therefore,it is possible to use the linkage molecular markers to assist selection and genetic improvement of the“curd sitting height”trait in cauliflower in early generations.In summary,the results of this study laid a preliminary research foundation for further locating and exploring the key genes controlling the“curd sitting height”of cauliflower,and ultimately using biotechnology to cultivate new varieties of cauliflower suitable for mechanized harvesting.