Trichoderma viride and Pseudomonas fluorescens Formulations Against Pythium aphanidermatum in in vitro

摘要

Chilli (Capsicum annuum L.) is an important spice crop cultivated throughout the world and India is one of the leading countries in chilli production. This crop has been affected by various fungal, bacterial and viral diseases. Among the fungal diseases, damping-off incited by Pythium aphanidermatum (Edson) Fitz., causes pre- and post-emergence damping-off in the nursery. This soil-borne pathogen has a wide host range of more than 400 plant species. Use of antagonistic organisms is a potential, non-chemical, eco-friendly and sustainable approach for managing plant disease. Trichoderma and Pseudomonas are the two most widely used biocontrol agents since they are reported to have antifungal, antinematode, plant-growth promoting and plant defense inducing activities (Zaidi et al., 2004). One of the obstacles to biocontrol has been the lack of suitable substrate as well as method for multiplication of antagonist. Several workers have tried the multiplication of biocontrol agents using different carriermaterials like talc-powder, wheat bran, saw dust, lignite, peat and vermiculite to control many soil-borne pathogens (Vidhyasekaran and Muthamilan, 1995; Vidhyasekaran et al., 1996 and Bora et al., 2004). The present investigation was carried out to evaluate the efficacy of various carrier materials such as fly ash, lignite, peat soil, rice bran, sugarcane baggase, talc powder (magnesium silicate ore) and wheat bran in sustaining the mycelial growth and population of biocontrol agents in different days of storage at room temperature.