Trichoderma harzianum formulations based on a biopolymeric hydrogel, ZnSO4 and their combination.

Abstract

Novel wet and dry formulations of Trichoderma harzianum are reported. These were prepared by entrapment of spores and/or mycelia into the swollen matrices of hydrogel, or by physical mixing with xerogel containing zinc sulphate (ZnSO4). T. harzianum exhibited significantly high survival in presence of pure ZnSO4 up to a concentration of 150 ppm, beyond which gradual decline in viability occurred. Both the wet and dry compositions exhibited excellent shelf life, with the viability of T. harzianum up to180 d without any sign of toxicity due to the hydrogel carrier per se or with the impregnated ZnSO4. The combination of T. harzianum + ZnSO4 exhibited higher bio-activity than T. Harzianum or ZnSO4 alone against the soil borne fungal pathogen Rhizoctonia solani.