Response of Leucaena leucocephala (Lam.) De Wit (Leucaena) Provenances to Aluminium in Potted Soil Experiment

Aims: To determine the level of acid or aluminium tolerance provenances in Leucaena (Leucaena leucocephala) a favourite agroforestry tree in Kenya.
Study Design: The set up was a 2-factor (provenance-aluminium) experiment in a completely randomized design with three (3) replications and data were subjected to multivariate analysis of variance.
Place and Duration of Study: Potted acid soil experiments were carried out at the Maseno ICRAF/KEFRI centre and Chepkoilel campus farm, Moi University, between June 2009 and July 2010.
Methodology: Potted acid soil experiments were carried out at the Maseno ICRAF/KEFRI centre (pH 4.8) and Chepkoilel campus farm, Moi University (pH 5.0) to assess the effect of varying aluminium concentrations on growth of three local leucaena provenances: K156 (Gede), K136 (Kibwezi) and KIT2724 (Kitale). Aluminium was applied at 0, 100, 200 and 300 μM. The number of leaves per seedling, seedling height, root length, root collar diameter and dry weight were recorded at 60 and 120 days after planting.
Results: Generally Aluminium at 100 μM significantly (p≤0.05) enhanced growth of the seedlings at both sites. However, aluminium at ≥ 200 μM reduced seedling growth.
Conclusion: The Leucaena provenance K156 could be used in acid soils because it is tolerant. However, more local provenances should be screened for acid tolerance.