Abstract
Endophytic fungi are a group of microorganisms living inside plant tissues without any immediate and visible symptoms, and in most cases have benefits for their host. In this research, 50 samples of healthy tomato plants were collected from Isfahan and Tehran provinces of Iran. Totally, 89 strains of endophytic fungi were isolated from root, stem, and leaf tissues. Based on morphological characteristics, the isolates were belonged to 12 different genera including Fusarium, Alternaria, Cladosporium, Acremonium, Arthrinium, Aspergillus, Penicillium, Moniliophthora, Rhizoctonia, Nigrospora, Trichoderma and Colletotrichum. The biocontrol effects of the isolates were investigated against Botrytis cinerea in vitro. Based on the results of dual culture and volatile organic compounds (VOC) production, six isolates were selected with the most inhibitory effect on B. cinerea that were belonging to the genus Fusarium. Among them, isolate 41R1 with 65.8 and 65% inhibitory rate on mycelia growth of the isolates B1 and B2, respectively, showed the highest value in the dual culture test. In the VOC test, isolate 28S1 had the most inhibitory effect on mycelia growth of isolates B1 and B2, with the values of 66.6 and 62.6%, respectively. Six selected isolates reduced the tomato grey mold disease severity about 35 to 58% in greenhouse. Isolate 28S1 increased the plant dry weight, but without significant effect on other plant growth indices. Isolates 41R1, 28S1, and 16S3 with the highest inhibition, were identified based on the partial sequence of tef-1α gene, which belonged to Fusarium falciforme, Fusarium falciforme and Fusarium solani species, respectively.