Establishment of the fungal entomopathogen Beauveria bassiana as a season long endophyte in jute (Corchorus olitorius) and its rapid detection using SCAR marker

An experiment was conducted to introduce the entomopathogen Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales) as an endophyte in jute (Corchorus olitorius), a bast fibre crop through seed treatment. Colonization of root, leaf, stem, capsule, and seed were assessed through plating on selective medium and PCR based detection using B. bassiana specific SCAR markers. Endophytic colonization was detected in all the plants grown from treated seeds, but all the plant parts were not colonized. Colonization was detected in leaves, stems, and green capsules but not in roots and seeds. The endophytic colonization was influenced by both plant part and sampling period. Colonization was greater in leaves (55.87%) compared to stems (12.53%) and capsules (42.44%). The percent colonization was higher in case of 60?days old plants (43.34%) than in 30?days (23.89%) and 120?days (35.39%) old plants. As B. bassiana has already been reported to be pathogenic on jute pests, namely semilooper (Anomis sabulifera) and bihar hairy caterpillar (Spilosoma obliqua), its season long endophytic colonization within jute plant suggests a novel approach of biological control of these pests through seed treatment with the entomopathogen.