Comparative Histological Evaluation of the Fruit of Ribes nigrum and Ribes rubrum

Abstract

To complete the wide range of studies on chemical composition and pharmacological potential of the fruit of Ribes nigrum and Ribes rubrum, this work aimed to perform a comparative morpho-anatomical characterization of the fruits of both species and complete previously records of black currant as frequently studied species. Microslides of fruits were made with rotation microtome, and then cross sections were stained with toluidine blue. Documentation and evaluation were carried out in microphotos. In R. rubrum, the epidermis cells are ovoid to round, while those of R. nigrum are rectangular to almost round. Under the epidermis, in both fruits, there are two layers of oval hypodermal cells. Underneath the hypodermal layers, parenchyma cells of different size with thin walls and scattered collateral closed bundles were detected. The seeds are embedded in a gelatinous sheath having large thin-walled cells. Endocarp separates the arillar tissue from parenchyma cells, in addition, a gap can be found among these layers, endocarp, arillar tissue, and seeds. The seed coat consists of sclerenchyma cells in both species. In conclusion, histological differences and similarities were described in the fruits of the selected Ribes species, highlighted the first morpho-anatomical description of the berry of Ribes rubrum.