Development of Sanitation Protocol for Leaf Explants of B. huillensis for in Vitro Culture

Brachylaena huillensis (Silver Oak) is a multipurpose timber tree species in the family of Asteraceae. There has been a very high demand for B. huillensis wood and its products leading to overexploitation. B. huillensis regenerates through seedlings. However, it produces seeds with poor germination. Seeds are also difficult to be collected because of small size. Many are eaten by insects and currently there is a lack of seed bank. The facts that have hindered and rendered the natural regeneration of the tree species were uncertain. The present investigation was carried out to develop sanitation protocol of B. huillensis using leaves as explants. Juvenile leaves from the tips of B. huillensis naturally growing seedlings were collected from Bombo West Forest Reserve in Tanzania. The leaves were washed and immersed in NaOCL containing various concentrations levels and two drops of tween 20. There was significant difference between the concentrations levels employed. However, the best results were obtained when leaf explants were immersed in 1.5% v/v NaOCL for ten minutes and later in ethanol for ten seconds and cultured on woody plant media medium containing antifungal (cefotaxime). Genuinely, the protocol is vital and so opens up the way for other subsequent stages for in vitro propagation of B. huillensis.