Selection of effective natural fungal pathogens of the rice leaf folder Cnaphalocrocis medinalis (Guenee) by in vitro assay Sahoo B, Behera KS, Dangar TK* Central Rice Research Institute, Cuttack-753006, Odisha, India *Email: dangartk@gmail.com
Online published on 12 June, 2014. Abstract The rice leaf folder (LF), Cnaphalocrocis medinalis (Guenee) was naturally infected by the fungal pathogens viz. Beauveria bassiana, Metarhizium anisopliae, Nomuraea rileyi, Fusarium oxysporum and Verticillium lecanii. In vitro condition, the pathogens affected 0–93.3% mortality of the 3rd instars LF larvae within 1–4 d. The isolates of Beauveria and Metarhizium spp. were more effective pathogens infecting 80–93.3% insects, whereas, the other fungi infected only 20–23.3% larvae in 96h. The isolates of B. bassiana and M. anisopliae produced different pathogenicity related exotoxins viz. amylase, cellulase, protease, chitinase, pectinase, lipase and lecithinase which would enhance their virulence. Higher level (>50%) of infectivity of B. bassiana and M. anisopliae envisaged that they can be exploited to control LF in the field. Besides, as all other fungi were also virulent to varying extents, they can be effective against LF in favourable conditions. Top Keywords Rice, leaf folder, fungal pathogen. Top |