Isolation and identification of fungi with bio-herbicidal activity in Cyperus rotundus

Objective: to isolate, identify selected fungi with bioherbicide activity on Cyperus rotundus Design/methodology/approach: In this research work we isolated fungi from healthy and diseased Cyperus spp. The plants were collected from different field sites of Cardenas and Huimanguillo, Tabasco, Mexico. The fungi were morphologically characterized and by molecular analysis of ITS region they were identified. The bioherbicidal potential was assessed by using phytopathogenic fungi isolated from diseases plants, then they were selected for pathogenicity and virulence test on C. rotundus. Results: Nine fungal genera were found to be associated to both healthy and diseased Cyperus. Only Curvularia, Fusarium and Pestalotiopsis were pathogenic, and they showed different levels of severity on C. rotundus. These fungi had a direct impact on reduction of plant height and the number of tiller emergence of C. rotundus was lower compared with the control without fungal inoculation Limitations on study/implications: the high cost of molecular identification of fungi to species level, unfavorable conditions for the bioassay at the greenhouse facility Findings/conclusions: This study provides insights that both Fusarium, Curvularia and Pestalotiopsis showed a preliminary potential micoherbicide effects on C. rotundus. However, we suggest more detailed research on host range determination, effects on seed germination of different Cyperus spp, weeds or cultivated plants in controlled conditions in order to test to a complete bioherbicidal potential of these fungal candidates. Keywords: Weeds, fungal endophytes, phytopathogenic fungi, bioherbicides