IN VITRO EVALUATION OF BIOCONTROL AGENTS AND FUNGICIDES ON WOOD DECAY FUNGI-GANODERMA ASSOCIATED WITH MORTALITY OF TREE LEGUMES

An experiment was conducted to isolate a number of biocontrol agent- Trichoderma spp. from infected spawn packets of oyster mushroom at National Mushroom Development and Extension Centre, Savar, Dhaka, Bangladesh. These bio-control agents were used as antagonist against four wild wood decay fungi of Ganoderma, viz., G. lucidum-1, G. lucidum-2, G. lucidum-3, G. applanatum and two cultivated G. lucidum-4, G.lucidum-6 under in vitro condition. An in vitro trial of Trichoderma spp. against Ganoderma were performed by dual culture, by treating with volatile, non-volatile and naturally untreated metabolites of bio-control agents. In dual culture, all the Trichoderma species showed 70- 100% mycelia inhibition of G. lucidum-1 and G. lucidum-2, 55.6-100% inhibition of G. lucidum-3, 20-66.7% of G. applanatum, 100% of G. lucidum-5, 75-100% of G. lucidum-6. Effects of heat killed extracts of Trichoderma spp. on growth of G. lucidum-2 (wild) and G. lucidum-6 (cultivated) were also evaluated. Fungicides Bavistin and Dithane M-45 were also used to investigate the mycelial growth inhibition of Ganoderma spp

SYMPTOMATOLOGY OF FUNGAL COMPETITORS ON OYSTER MUSHROOM’S SPAWN PACKETS AND IN VITRO EVALUATION USING PHYTOEXTRACTS AND A FUNGICIDE

An experiment was conducted to find out the fungal competitors and symptom studies in damaged Oyster Mushroom spawn packets at National Mushroom Development and Extension Center, Savar, Dhaka, Bangladesh. A total of nine fungal competitors of oyster mushroom were isolated and identified namely- Trichoderma harzianum Rifai, T. viride Pers. (Green strain), T. viride Pers. (Yellow strain), T. koningii Oudem, Mucor hiemalis Wehmer, Papulaspora byssina Hotson, Neurospora sp. Shear and B.O. Dodge., Aspergillus flavus Link., and Botryodiplodia theobromae Pat. on the basis of microscopic, morphological and cultural characteristics. To produce oyster mushroom in an eco-friendly manner and to find out their antifungal potency, 23 plant species belonging to 19 families were screened out against isolated nine fungal competitors of oyster mushroom. Among 23 extracts, the maximum (44%) mycelial inhibition of T. harzianum was found due to Aegle marmelos whereas Eclipta alba showed the highest mycelial inhibition (62%) of T. viride (Green strain); in case of T. viride (Yellow strain), Cassia tora exhibited the highest mycelial inhibition (39%); Diospyros cordifolia showed the maximum mycelial inhibition (48%) of T. koningii; Curcuma longa (rhizome) gave the maximum mycelial inhibition (90%) of Neurospora sp. There were no significant effects found to control of P. byssina, B. theobromae, M. hiemalis and A. flavus due to 23 different types of botanicals tested. Trichoderma harzianum, T. viride (Green strain), T. viride (Yellow strain), T. koningii, A. flavus, Neurospora sp. and P. byssina was successfully inhibited by 30, 50 and 70 ppm of fungicide-Bavistin 50 WP but B. theobromae and M. hiemalis were not affected by Bavistin at mentioned concentration