Study of the efficacy of five growing media for nursery production of an endangered species, Afzelia africana Smith ex Pers in Côte d'Ivoire

Abstract

Afzelia africana Smith ex Pers is an endangered plant species listed on the International Union for Conservation of Nature (IUCN) Red List. The low level of natural regeneration of this species requires it to be reproduced in a controlled environment in order to reconstitute its population by providing good quality seedlings. As the growing medium is an important factor in the quality of the seedlings, the influence of the substrates soil + wood chip compost, soil + poultry droppings, soil + rice straw compost, soil + cocoa pod husk compost and soil on the germination and growth of Afzelia africana in the nursery was evaluated through a completely randomised design. The soil + wood chips compost performed best, with a high germination rate (76.7%). It enabled the production of taller seedlings (15.6 cm; p = 0.004), with larger collar diameters (4.4 mm; p = 0.001), higher total dry matter (2.25 g.plant-1; p = 0.005) and higher root dry matter (2.25 g.plant-1; p = 0.005). The mixture of three parts soil + one part poultry droppings was toxic for the seedlings, resulting in 60.6% mortality. The use of growing media containing a mixture of soil and wood chips compost is effective for the production of vigorous seedlings. This compost can be recommended for nursery production of Afzelia africana.