Using leaf micromorphology to characterize Iranian species of Ribes (Grossulariaceae)

This electron microscope study investigated the micromorphological characteristics of the leaf epidermis of 5 species (10 populations) of Ribes (Grossulariaceae) in Iran: R. biebersteinii, R. uva-crispa, R. orientale, R. aureum, and R. khorasanicum. Samples were collected and identified, and the similarities between the species were evaluated using information from micromorphological traits of leaf epidermis and multivariate analysis (cluster analysis and principal component analysis). The traits useful for discriminating the species were presence or absence of hairs and glandular trichomes, presence or absence of granular with verrucae on hair surface, position of hairs on epidermal surface, hair location on the leaf (lamina, leaf margin, midrib), stomata shape, wax distribution on stomata, prominence and shape of anticlinal walls and outer periclinal layer, and epicuticular wax sculpturing. An identification key based on these leaf micromorphological characters is provided for Ribes species in Iran. The multivariate analysis of micromorphological traits was efficient for inter- and intra-specific delimitation. The present findings correspond to a large extent with existing classifications.