In-vitro compatibility of Trichoderma harzianum with systemic fungicides

Abstract

Trichoderma spp. are also known as effective bio-control agents against soil-borne pathogens of several important crops. Integration of chemicals and bio-control agents has been the subject of research during recent years. The potential value of bio-pesticides for the control of important plant pathogens requires investigation due to the general requirement for very low pesticides residues in foodstuffs and concerns over the increasing development of resistance to the different classes of chemicals. The aim of the present study was to check the compatibility of different fungicides viz., Hexaconazole, Nativo (Tebuconazole 50%+ Trifloxystobin 25%), Propiconazole and Tebuconazole were tested with their different doses of 10, 15, 20 and 25 ppm in vitro for their compatibility with T. harzianum strain IRRI-1 using poisoned food technique. all the four concentrations of Nativo were highly compatible with low toxic effect against T. harzianum strain IRRI-1 in vitro. As there was 74.42, 79.07, 93.02 and 95.35 percent inhibition of radial growth of T. harzianum strain IRRI-1 due to Nativo at 10ppm, 15ppm, 20ppm and 25ppm concentrations respectively, even after a prolong exposure i.e. up to 96 hours (4 days). 15 and 20 ppm concentration of Propiconazole was completely inhibitory up to 48 hours but after 72 hours, a little growth of T. harzianum strain IRRI-1was visible. 25 ppm concentration of Propiconazole was completely inhibitory up to 96 hours was noticed that the systemic fungicide i.e. Nativo and Propiconazole were comparatively safer, than Hexaconazole and Tebuconazole which exhibited acute toxicity for growth of T. harzianum strain IRRI-1.