Endophytic Fungi of Bitter Melon (Momordica charantia) in Guangdong Province, China

Abstract

Endophytic fungi can mutualistically interact with their host plants by deterring herbivores. Overall 1172 endophytic fungal isolates were recovered from roots, stems, leaves, flowers and fruits of bitter melon, Momordica charantia, at five sites in Guangdong Province. These isolates were identified to 25 genera using morphological and molecular characteristics. The endophyte communities at the five sites were similar. Alternaria alternata, Aspergillus spp., Cladosporium spp., Colletotrichum spp., Nigrospora spp., Penicillium spp., Arthrinium spp., Chaetimium spp., Curvularia spp., Fusarium spp., Phoma spp., and Phomopsis spp. were isolated from at least three of the five sites. The coefficient of similarity for endophytes ranged from 60.6% to 83.3% between any two sites. There were significant differences in the species composition of endophytes recovered from different tissues of bitter melon. Fusarium spp. was the most frequent in root and stem samples, Colletotrichum spp. in leaf samples, A. alternata in flower samples, and Cladosporium spp. in fruit samples. The coefficients of similarity for endophytes were between 42.9% and 80.0% from any two tissues. We found that the composition of endophytes of bitter melon was relatively stable across sites, but differed greatly among tissues. We also found that there were fewer insects such as aphids (Homoptera: Aphididae), leafminers (Lepidoptera, Gracillariidae), and cotton leafworms Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) collected from the leaves of bitter melon at the Huadu site compared to those collected at the Yunfu site. Whether this is related to the endophyte communities isolated from different sites requires further research.