Germination of seeds from earlier fruits of bitter and sweet African bush mango trees

Abstract

Plant species are basic component of agro-biodiversity and a complex situation created by their own ability to disperse; and the rapid changes of land use and climate is endangering their efficient conservation and use. In order to increase knowledge of bitter and sweet African bush mango trees (ABMTs) (Irvingia spp.: Irvingiaceae) and support small-scale farmers in establishing uniform plantations, germinability of earlier fruited trees was assessed. Germination rate and speed, from both systems were analysed in order to differentiate bitter and sweet bush mango trees and identify types of seeds suitable to overcome the climatic hindrances for uniform plantations establishment in the Dahomey Gap, a drier eco-region where savannah reach the sea coast including Benin and Togo. Fresh seeds of both bitter and sweet fruited trees, showed the highest growth  performance (98 - 100%). Seed germination speed significantly depended on the drying level and the germination system (sunshine versus covered condition). The speed was higher for fresh seeds in closed condition, confirming bush mango seeds as typically recalcitrant, but not strictly photoblastic. Results also demonstrated that bush mango seeds do not
require specific treatments for optimising germination. Germination did not depend on mango tree type (bitter or sweet) and fresh seeds were the best material for establishing viable and uniform plantations.

Key Words: Benin, Dahomey gap, Irvingia