Assessment of the Diversity of Leaf Epidermal Traits of Dipcadi Filamentosum Medik Among Different Co-Geographical Regions in Nigeria

Abstract

This study was conducted to disentangle the influence of environmental variables on the spatial patterns in leaf epidermal traits (i.e. stomatal occurrence, stomatal traits and epidermal cells) in some morphologically different populations of Dipcadi filamentosum Medik in Nigeria. The stomatal occurrence and the stomatal length (SL), stomatal width (SW), stomatal size (SS), stomatal density (SD) and stomatal index (SI) of 13 ecotypes of D. filamentosum from 11 locations in Nigeria were studied. All the populations were amphistomatous with 100% tetracytic stomatal complex type. The epidermal cells were rectangular in shape with straight to curve anticlinal cell wall pattern. Contrarily, the species from the Northern eco-geographical location had larger SS, higher SD, longer SL, higher SI and wider SW and higher epidermal cell density than those from the Southern eco-geographical location where there is higher annual rainfall and lower temperature. Temperature and rainfall affected SD, SI and SL, SS and SW whereas the epidermal cells and anticlinal cell walls were not affected. Variations were observed within and between the populations from the 4 eco-geographical locations.The variables observed among the 4 eco-geographical populations of D. filamentosum showed that effects of environmental factors are partial on the leaf epidermal traits of the plant. The evidences from the studied characters are good taxonomic features or indicators hence they can be used to separate them to different species.