Comparative Analysis of Leaf Characteristics of Irvingia gabonensis and Irvingia wombolu, in Southern Nigeria: Implication for Food Security and Policy in Nigeria

Irvingia gabonensisis an indigenous fruit tree species of high economic importance in the forest zone of West and Central Africa . The species was earlier identified to exist in two varietal forms which were var. gabonensis and var. excelsa, due mainly to the difference in the quality of the respective fruits. These varieties now regarded as Irvingia gabonensis and Irvingia wombolu respectively show comparative characteristics which need further examination. Investigation of the leaf parameters was carried out to generate further evidence of proper distinction between the two species. The investigation involved the comparison of leaf attributes sourced from three distinct geographical locations in Southern Nigeria. The methodology involved initial investigation of leaves of seedlings in a forest tree nursery in one location, and then mature trees from three locations in Southern Nigeria. Data were generated using parameters of leaf length, leaf width and venation angles, and were analysed using descriptive statistics and tests of significance. The results showed that the length of the seedling leaves of the two species were significantly different, while the width is not at 1% probability level. This difference was observed in the mature leaves as well, at 1% probability level. In addition the venation angles of I. wombolu were consistently larger than that of I. gabonensis, both at seedling and mature phases thus buttressing the differences in the two species. Based on the findings, it is pertinent to pay attention to vegetative characters while selecting the species partially or wholly for further development towards food security programs.