Anatomical traits of sweet pepper (Capsicum annuum L.) fruit

Abstract

The micromorphology of the epidermis as well as the anatomy of the pericarp and fruit pedicle in Capsicum annuum L., cv. 'Red Knight F₁', were studied using light and scanning electron microscopy. The pericarp was found to consist of an epidermis with strongly thickened outer walls, several layers of tangential and angular collenchyma as well as multi-layered parenchyma composed of cells of varying size in which very large lobed nuclei were observed. Chromoplasts were found in the cells of the above-mentioned tissues. The inner epidermis of the pericarp was characterized by thick cell walls and numerous straight pits. Among the tissues of the fruit pedicle, we observed epidermis with numerous stomata, collenchyma, chlorenchyma with very large intercellular spaces, small clusters of sclerenchyma, secondary phloem and xylem as well live and dead cells of the pith which were characterized by the presence of thin walls with numerous pits. The structural traits of the pericarp of the red pepper cultivar under study show adaptations to significantly reduced transpiration, which is an important feature during storage. At the same time, the strongly thickened and cutinized walls of the fruit contribute to a reduction in its digestibility and impede nutrient penetration in non-root feeding.