Effect of Seed Source and Watering Intervals on Growth and Dry Matter Yield of Shea Butter Tree (Vitellaria paradoxa Gaertn F.) Seedlings

Shea butter tree seeds obtained from five locations in Guinea and Sudan savanna zones of Nigeria were evaluated for seedling growth under three watering intervals. The accessions were named after the site of collection, which included Makurdi, Minna, Jalingo, Yola and Kano while the watering intervals included 3, 6, and 9 day-intervals. Factorial combinations of the accessions and the watering intervals were laid out in a completely randomized design (CRD) replicated three times. Data on growth pattern, dry matter yield and distribution were collected between July 2006 and April 2007. Result indicated that accession had significant (P < 0.05) effect on all traits except number of leaves, total shoot length, shoot dry matter content and dry matter distribution to the roots and leaves. Watering intervals exerted significant effect only on fresh weight of roots, total fresh weight of seedling, root dry weight, leaf dry weight, total plant dry weight, and per cent total dry matter. Generally, the Jalingo accession was superior in most seedling attributes while Makurdi was the most inferior, a pattern probably associated with heavier seed weight of Jalingo and light seeds from Makurdi used for planting. The interaction between accession and watering intervals was significant (P < 0.05) on most characters except seedling girth, total shoot length, fresh weight of shoot, dry matter distribution to the root and per cent total dry matter. Dry matter content of the leaves and roots varied significantly (P < 0.05) with seedlings from the Makurdi seed source giving the lowest values. Amount of dry matter allocated to the roots was more than 70% in all the accessions. Generally, the longest watering interval produced seedlings with the longest roots. The Kano accession appeared more tolerant to water stress judging mainly from its dry weight/matter traits. On the other hand, the Minna provenance performed better under the 3 and 6 days watering intervals. Other accessions performed more or less uniformly under all watering intervals Keywords: Shea butter tree seeds, Accession, Watering intervals, Seedling growth, Dry matterBio-Research Vol. 6 (1) 2008: pp. 303-30