Solid State Fermentation of Trichoderma harzianum on Agricultural Waste (Banana peels)

Abstract

Trichoderma harzianum was the commercial strain of the laboratory of Biological control of plant pathogens, Department of Plant Pathology, Kasesart University that was studied for biofertilizer production by using agro-waste (banana peels). T. harzianum grew actively on Potato Dextrose Agar (PDA) medium, the colony of T. harzianum formed the compact mycelium with green pigments. It produced the round smooth, small green conidia. Growth of mycelium of T. harzianum ontwo different solid medium (PDA and BPA) was not quite different. But the mycelium of T. harzianum on Banana Peels Agar (BPA) were rather thin and flat. Although growth on PDA was slightly better than on BPA. No clear zone was produced around the single culture of T. harzianum on Carboxymethyl methyl cellulose sodium salt congo red solid medium + 2% banana peels (CMCc + 2 % BP).

Antifungal properties of T. harzianum were tested against soilborne phytopathogenic fungi, such as Fusarium oxysporum, Pythium aphanidermatum and Phytophthora palmivola by dual culture testing on different solid medium (PDA, BPA and CMCc + 2% BP). Three replicates were prepared for each pairing. The reduction in growth of the three genus of soilborne phytopathogenic fungi was evidenced. The maximum inhibition was observed in dual culture of P. palmivola, and the least inhibition was observed in dual culture of P. aphanidermatum.

The quality of banana peel biofertilizer produced by T. harzianum was analyzed. The results showed the ratio of Carbon to Nitrogen (C:N) of 35 : 1. It contained 63 to 63.2 percent of organic matter. Level of nutrients in available forms to the plants, especially K2 O, was greater than Thai organic fertilizer standards of Department of Agriculture. Decomposed banana peels tended to increase both pH and the soluble salts with high electrical conductivity (pH 7.78-7.8, EC 12.10 dS/M)

T. harzianum was cultivated under solid-state fermentation (SSF) by using banana peels as substrate. Spore yields were obtained at 4.7 x 107 spores/ml. (1.8 x 108 spores/gram of banana peels). Dry spores were harvested and dried at 50-60 degree of Cenceus. They would be stored dry about 1 month at room temperature in sterilisable plasticbox.