观赏辣椒杂种优势及重要性状遗传规律分析

  目的  探索观赏辣椒杂种优势以及观赏性状遗传规律，促进观赏辣椒新品种培育以及优良性状的保留。  方法  以簇生椒Capsicum annuum ‘Salsa XP Red’卵圆形叶片自交系(P15)与单生椒C. annuum ‘Salsa Deep Orange’披针形叶片自交系(P6)为亲本，配置正交组合P6×P15，反交组合P15×P6，并构建F₂群体，研究观赏辣椒果实着生方式、叶形和株型性状的遗传规律。  结果  P6和P15的叶片大小、株高、侧枝数等指标均存在显著差异(P＜0.05)。正反交观赏辣椒F₁组合均在株高、株幅和叶片尺寸等性状上表现较高的杂种优势。在正反交的F₂群体中，方差最大的5个农艺性状从大到小依次为叶长、单株结果数、叶柄长、株幅、株高，且正反交群体的株型与叶形各性状间存在极显著相关性(P＜0.01)。卡方检验表明:正反交F₂代群体质量性状分离比结果中，果实簇生性状对单生性状、有限生长对无限生长均为单基因隐性遗传；开展型株型对直立型株型、披针形叶对卵圆形叶均由双基因控制，且具有隐性上位作用。  结论  观赏辣椒杂交亲本与F₁代组合在单株结果数、分枝级数等5个性状上存在显著差异，其中株型变异系数最小，单果果实品质与单株果数变异系数较大，叶长和单株结果数性状的单株间差异最显著。对观赏辣椒重要性状遗传规律分析表明:果实着生方式簇生对单生、有限生长对无限生长是单基因控制隐性遗传性状。图2表8参22

Genetic analysis on heterosis and important traits of ornamental pepper hybrids

  Objective  This research aims to explore the heterosis of ornamental pepper and the genetic law of ornamental traits, to promote the cultivation of new varieties of ornamental pepper and the retention of excellent traits.  Method  The oval leaf inbred line (P15) of cluster pepper (Capsicum annuum ‘Salsa XP Red’) and the lanceolate leaf inbred line (P6) of single pepper (C. annuum ‘Salsa Deep Orange’) were used as parents, an orthogonal combination P6×P15 and an inverse combination P15×P6 were configured, and F₂ population was constructed to explore the inheritance of fruit bearing pattern, leaf shape and plant type of ornamental pepper.  Result  There were significant differences between P6 and P15 in leaf size, plant height and number of lateral branches (P＜0.05). All F₁ combinations of cross ornamental pepper showed high heterosis in plant height, plant width and leaf shape. In F₂ population of reciprocal cross, the descending order of agronomic characters with the largest variance was leaf length, fruit number per plant, petiole length, plant width and plant height, and there was a significant correlation between plant type and leaf type traits (P＜0.01). The Chi-square test showed that in the results of the segregation ratio of quality traits in the F₂ generations of reciprocal crosses, the fruit cluster traits were inherited in a single gene recessively for solitary traits and limited growth versus infinite growth. The developmental plant type versus the erect plant type and the lanceolate leaf versus the oval leaf were both controlled by two genes, and had recessive epistasis.  Conclusion  There are significant differences between ornamental pepper hybrid parents and F₁ generation in 5 traits, such as the number of fruit per plant and the number of branching grades. Among them, the coefficient of variation of plant type is the smallest, the coefficient of variation of fruit weight and fruit number per plant is larger, and the difference of leaf length and fruit number per plant is the most significant. The analysis of the inheritance law of the important traits of ornamental pepper reveals that the fruiting bearing pattern of clusters versus solitary and limited branch versus infinite branch are recessive genetic traits controlled by single gene.Ch, 2 fig. 8 tab. 22 ref.]