Efficacy of plant leaf extracts on the mycelial growthof kolanuts storage pathogens, Lasiodioplodia theobromae and Fusarium pallidoroseum

The efficacy of leaf extracts of five plant species namely: Glyricidia sepium (Jacq.) Linn, Tectona grandis Linn.Ocimum gratissimum Linn. Anacardium occidentales Linn. and Carica papaya Linn. against storage fungiLasiodioplodia theobromae and Fusarium pallidoroseum was evaluated. The potency of these leaf extracts after storage at ambient temperature for 15 and 30 days, respectively was also tested on the radial growth ofL. theobromae and F. pallidoroseum. The results indicate that leaf extracts from O. gratissimum and A. occidentales are effective in inhibiting the radial growth of L. theobromae and F. pallidoroseum, respectively. O. gratissimum even at 2.5% concentration gave 35.89% mycelial growth inhibition of L. theobromae and 10% concentration gave 50.3% mycelial growth inhibition after five days. The extract of C. papaya exhibited less antifungal activity than either O. gratissimum or A. occidentales. Generally, with the exception of C. papayaleaf extract, there was no significant difference (P = 0.05) between the fresh leaf extract and the stored extracts in the inhibition of the mycelial growth of either L. theobromae or F. pallidoroseum and the potency of the leaf extracts was retained even after 30 days of storage at ambient temperature.   Key words: Leaf extracts, kolanuts, storage pathogens, mycelial growth.