Some Physiological and Environmental Factors Influencing the Vegetative Propagation of the Shea Tree (Vitellaria paradoxa Gaernt)

Abstract

The Shea tree (Vitellaria paradoxa Gaernt) is an economic tree found in the interior savanna belt of West Africa. The tree is recalcitrant and does not respond to most propagation methods. Vegetative propagation of shea tree by stem cuttings using different wood types and rooting hormone during different seasons were studied at Bole, Tafo and Fumesua located in the Northern, Eastern and Ashanti Regions of Ghana respectively. Rooting was significantly affected by wood type, hormone treatment and season of propagation, with cuttings from coppiced trees combined with Seradix ‘3’ rooting powder giving the best results. Anatomical and biochemical studies showed remarkable effects of these factors on rooting in shea stem cuttings. Cuttings required significantly high levels of carbohydrate and total free phenols for root initiation and development. Coppiced cuttings had the highest (p<0.05) carbohydrate and total free phenol levels, which made them perform better in rooting than the other wood type. The anatomical studies showed the presence of root primodia in the coppiced cuttings, with all the wood types showing discontinuous sclerenchyma cells. Cuttings set in the rainy season (June to August) performed better than those set in the dry season (October to January).

Keywords: Shea tree, vegetative propagation, Seradix 3 powder, sclerenchyma cells, root primodia