Efficacy of endophytic fungi isolated from Sesbania javanica against plant pathogenic fungi

Abstract

One hundred and forty three isolates of endophytic fungi were obtained from leaves and twigs of Sesbania javanica in Ayutthaya. They were identified into 7 genera and 5 species based on morphological characteristics, including Chaetomium globosum, Curvularia lunata, Curvularia spp., Nigrosporium sphaerica, Pestalotiopsis spp., Phomopsis spp., Talaromyces trachyspermus, Zygosporium masonii, and unidentified fungi which produced only sterile mycelium. The twenty-one isolates of endophytic fungi were selected for antagonistic activity testing with 10 species of plant pathogenic fungi in vitro. T. trachyspermus isolate 1-41-4 showed highly inhibited mycelial growth of Bipolaris maydis (causing leaf blight of corn) and Alternaria alternata (causing fruit rot of Chinese pear) at 64.8% and 76.7%, respectively. In addition, endophytic fungi Phomopsis sp. isolate 3-212-2 could inhibit more than 70% mycelial growth of Colletotrichum spp. (causing anthracnose disease of fruit and vegetable), and also inhibited more than 60% mycelial growth of Fusarium oxysporum (causing wilt disease of tomato) and Phytophthora palmivora (causing root and stem rot of durian). Endophytic fungi C. globosum isolates 46-101-2 and 53-84-5 inhibited Rhizoctonia solani(causing sheath leaf rot of corn) and Sclerotium rolfsii (causing root and stem rot of mung bean) at 65% and 58%, respectively. The rest of endophytic fungi produced only moderate inhibition of the radial growth of plant pathogens.