Abstract:

【Objective】 The study of genetic diversity of pepper germplasm resources is an important basis of pepper breeding, and the investigation and study of suitable regional germplasm resources can screen out the core germplasm resources with excellent performance, which can provide theoretical basis for the improvement and innovation of pepper varieties. 【Methods】 In this study, 272 pepper germplasm resources were collected for genetic diversity analysis, correlation analysis, path analysis, principal component analysis and cluster analysis. 【Results】 The results showed that the distribution frequency of 22 quality traits was different, the coefficient of variation was between 12.3% and 79.78%, and the genetic diversity index was between 0.8 and 2.4, with the largest fruit type distribution and the highest genetic diversity index. The average coefficient of variation of the quantitative shape was 47.59%, and the coefficient of variation of the fruit-related traits was the largest, both exceeding 50%. Correlation analysis showed that plant height, plant width, first flower node number, commercial fruit transverse diameter, placental size, pulp thickness, single fruit weight, fruit per plant, yield per plant and seed weight were all significantly related. Stepwise regression analysis found that there was a significantly linear relationship between yield per plant, commercial longitudinal diameter, placental size, total fruit number, number of fruits per plant, number of ventricles and total yield (Y=0.202+0.042X₁₀+0.340X₁₃-0.175X₁₅+0.002X₁₇-0.01X₁₈+4.09X₁₉(R ²=0.941,F=6.449,P=0.001)). From the five principal component analyses, the number of fruit per plant, yield, fruit weight, commercial fruit transverse diameter, leaf length and width, fruit thickness, placental size, seed weight, and number of side branches were correlated with total yield. In addition, through SPSS software analysis, the 272 peppers could be divided into 6 categories at a distance of 7.5. 【Conclusion】 The higher the coefficient of variation, the lower the genetic stability, and the number of fruit per plant, yield per plant, weight per fruit, transverse diameter of fruit, size of placenta and seed weight are important agronomic traits directly related to total pepper yield.

Key words: Capsicum annuum L.; germplasm resources; genetic diversity analysis

摘要： 目的 研究适宜区域种质资源群体,筛选出优良表现的核心种质资源,为辣椒品种改良创新提供理论依据。方法 对收集的272份辣椒种质资源材料进行遗传多样性、相关性、通径、主成分和聚类分析。结果 22个质量性状的分布频率不同,其变异系数在12.3%~79.78%,遗传多样性指数在0.8~2.4,其中果形分布类型最大,遗传多样性指数也最高。数量形状的变异系数平均值为47.59%,与果实相关性状的变异系数最大,均超过了50%。株高、株幅、首花节位数、商品果横径、胎座大小、果肉厚、单果重、单株果数、单株产量和种子重均与总产量极显著相关。单株产量、商品果纵径、胎座大小、总果数、单株果数、心室数与总产量存在显著的线性关系Y=0.202+0.042X₁₀+0.340X₁₃-0.175X₁₅+0.002X₁₇-0.01X₁₈+4.09X₁₉(R ²=0.941,F=6.449,P=0.001)。筛选出单株果数、单产、果重、商品果横径、叶片长宽、果肉厚、胎座大小、种子百粒重、侧枝数与总产量显著相关(P<0.05)。在欧式距离为7.5处,可将这272份辣椒种资分为6类。 结论 变异系数越高,遗传稳定性越低,且植株单株果数、单株产量、单果重、果实横径、胎座大小、种子重是与辣椒总产量直接相关的重要农艺性状。

关键词: 辣椒, 种质资源, 遗传多样性分析