High-throughput Characterization of Fruit Phenotypic Diversity among New Mexican Chile Pepper (Capsicum spp.) Using the Tomato Analyzer Software

Abstract

Fruit architecture and morphology-related traits are among the determinants of fruit diversity and are major contributors to yield and yield potential in chile pepper (Capsicum spp.). This study aimed to characterize 105 genotypes of a Capsicum diversity panel consisting of cultivars, breeding lines, landrace, and wild species belonging to twelve different pod (fruit) types, for 32 morphometric Tomato Analyzer (TA) descriptors. Hierarchical cluster analysis grouped the genotypes into eight clusters based on the TA descriptors. A multivariate principal component analysis yielded two principal components, PC1 and PC2, which explained 53.24% and 10.11% of the variation in fruit diversity, respectively. The basic measurements—namely, perimeter, area, width midheight, maximum width, height midwidth, maximum height, and curved height were the most discriminating descriptors with a maximum contribution to the overall fruit shape. There was a strong, positive correlation for basic measurements and fruit shape index, whereas blockiness was negatively correlated with distal angle macro. Additive genetic effects and high heritability for the fruit traits were observed. Results of this study will provide valuable information to breed high-yielding chile pepper cultivars based on fruit morphology traits.

Keywords

• domestication
• fruit shape
• fruit size
• genetic advance
• hierarchical clustering
• principal component analysis