Effect of temperature on growth and antagonistic activity of Trichoderma spp against Macrophomina phaseolina

Abstract

Studies were carried out on the influence of temperature on growth, survival and antagonistic performance of various strains of Trichoderma spp. against groundnut dry root-rot pathogen Macrophomina phaseolina (Tassi.) Goid. Different isolates of Trichoderma viride, T. harzianum, T. longibrachiatum, T. Hamatum, T. koningii and T. pseudokoningii were employed at various temperatures, viz., 15, 20, 25, 30, 35, 40 and 45°C for studying its cultural behaviour and antagonistic ability. Increased growth of the pathogen (M. phaseolina), and growth, sporulation and biomass production of the fungal antagonist (Trichoderma spp.) were observed between 25 and 35°C. Antagonistic activity of Trichoderma spp. against M. phaseolina was decreased with increase in temperature except for T. pseudokoningii, which showed maximum inhibition at 35°C. Survival of Trichoderma spp. on seed coat was maximum at lower temperature (15°C). At all the temperature regimes T. harzianum strain Th-5 has shown higher suppression of the root-rot pathogen, better growth and survival than strains of other species.