ANTAGONISTIC ACTIVITY OF RHIZOSPHERE FUNGI AGAINST EARLY BLIGHT OF TOMATO CAUSED BY ALTERNARIA ALTERNATA

Abstract

Eight fungi were isolated from rhizosphere soil of tomato plants and their antagonistic properties were studied in vitro against early blight pathogen, Alternaria alternata f. sp. Lycopersici (AAL). Different grades of colony interaction were observed in dual culture between AAL and antagonistic fungi inhibiting fungal growth. Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus, Curvularia sp, Fusarium solani, Penicilliumsp and Trichoderma harzianum showed inhibitory effect against AAL, in which maximum inhibition was observed by Trichoderma harzianum (63%) and significantly least effect was seen by Fusarium solani (34%). Further investigation on their bio efficacy, plant growth promotion activity under field condition and mechanism of action against the pathogens can be carried out which helps in complete understanding and usage of rhizosphere microorganism as effective bioagents in plant disease management.