A survey of farmers’ fields in Bihar in eastern India to assess the status of fungal diseases of Japanese mint (Mentha arvensis L.)

Japanese mint commonly called Mentha or corn mint is grown throughoutIndia as an evergreen perennial herb. Mentha is susceptible to many diseases and toidentify major diseases, a roving survey was conducted in major Mentha growing areasof Samastipur, Muzzafarpur and Begusarai districts of Bihar. During the survey offarmers’ fields, Alternaria leaf blightwas recorded to cause highest yield losses with 32.20–64.40% diseaseseverity. Fusarium wilt was also observed andconsidered as an emerging disease in Mentha which recorded up to 37% diseaseincidence during the survey period. Pathogens causing leaf blight and wilt werecollected from diseased Mentha plants and identified based on morpho-molecularcharacteristics. Nucleotide sequence analysis of the internal transcribed spacers(ITS1 and ITS5) enabled to confirm the morphological identification of Fusarium at the species level as Fusarium solani and F.equiseti and Alternaria species asAlternaria alternata. Pathogenicity test wasperformed on one month old Mentha plants which indicated that all the pathogensidentified were found pathogenic to Mentha.