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Sugarcane is one of the important commercial crop in India and white grubs are one of the serious pests of this crop. The present study was taken up to study the efficacy of entomopathogenic fungi against Holotrichia serrata (Fabricius) in sugarcane. Laboratory bioassay studies were conducted using five strains of Metarhizium anisopliae (ICAR-NBAIR Ma-4, Ma-6, Ma-11, Ma-14a & Ma-35) and one strain of Beauveria bassiana (ICAR-NBAIR Bb-5a) on third instar grubs of H. serrata at the concentration of 1 × 108 spores/ml. M. anisopliae (ICAR-NBAIR Ma-4) strain showed 100% mortality of the grubs and the rest of the strains showed 56–80% mortality of H. serrata. Dose and time mortality studies with aqueous spore suspensions and talc formulation (2% WP) of M. anisopliae (ICAR-NBAIR Ma-4 strain) showed LC50 value of 6.67 × 104 spores/ml and 1.72 g/l andLT50 value of 122.02 h at spore dose of 1 × 108 spores/ml and 183.86 h at the dose of 5 g/l. Further field evaluation was conducted in white grub infested sugarcane during 2016–17 and 2017–18 using M. anisopliae (ICAR-NBAIR Ma-4 strain) and B. bassiana (ICAR-NBAIR Bb-5a) for management of white grubs, H. serrata in Karnataka state of India. The results showed soil applications of 250 kg of M. anisopliae, (ICAR-NBAIR Ma-4) enriched Farmyard manure per hectare two times (June & July) effectively reduced the grub population of H. serrata by 86–89% leading to reduced plant damage and increased yield (33–34%). This treatment was better than the insecticidal application in the management of sugarcane white grubs.

Spodoptera frugiperda (J E Smith) (fall armyworm) (Lepidoptera: Noctuidae), is a key pest of maize that has recently entered in India causing damage and yield loss. A biocontrol-based integrated pest management (IPM) strategy was designed and evaluated in farmer’s field during rabi and kharif season (2018–2019). IPM strategy comprising installation of controlled release FAW pheromone traps, four releases of Trichogramma pretiosum Riley, two sprays of neem oil, one spray of each Bacillus thuringiensis (NBAIR-BT25) and Metarizium anisopliae (NBAIR Ma-35) resulted in 76 and 71.64% egg mass; 80 and 74.44% larval population reduction at 60 days after treatment during rabi and kharif season, respectively. Cob yield per acre in biocontrol-based IPM field was higher than the farmer’s practice (6–7 sprays of emamectin benzoate 5% SG) during both the seasons, and it resulted in 38.3 and 42.29% gain in yield per acre during rabi and kharif, respectively. Therefore, this module forms a base to manage the fall armyworm in an eco-friendly and farmer friendly manner. Future research with other alternatives has also been discussed.

Ten indigenous entomofungal strains ofBeauveria bassiana,Metarhizium anisopliae, andM. rileyiwere evaluated against 2nd instar larvae of the maize fall armyworm (FAW)Spodptera frugiperda(J. E. Smith) (Lepidoptera: Noctuidae) in a laboratory bioassay. Among the ten strains tested,M. anisopliaeICAR-NBAIR Ma-35 caused 67.8% mortality, followed byB. bassianaICAR-NBAIR Bb-45 with 64.3%, and ICAR-NBAIR Bb-11 with 57.1% mortality. Rest of the isolates showed 10.7–28.6% mortality. ICAR-NBAIR Ma-35 showed LC50of 1.1 × 107spores/ml and LT50at 1 × 108spores/ml is 86.04 h and ICAR-NBAIR Bb-45 showed LC50of 1.9 × 107spores/ml and LT50at 1 × 108spores/ml is 88.30 h. Field evaluation with these two promising strains were conducted against maize fall armyworm for 2 years (2018 and 2019) at ICAR-National Bureau of Agricultural Insect Resources experimental farm, Bengaluru, Karnataka, India. Field trial results indicated 68 and 69% reduction of FAW infestation and 55 and 62% increase in yield in the plots treated withM. anisopliaeICAR-NBAIR Ma-35/B. bassianaICAR-NBAIR Bb-45, respectively, during 2018. In 2019, 70 and 76% reduction of FAW infestation and 44 and 55% increase in yield were observed in the plots treated with these two entomofungal pathogens, respectively.

The present study was conducted to examine the ability of six promising indigenous isolates of Beauveria bassiana (NBAII-Bb-5a, 7, 14, 19, 23 and 45) as an endophyte in maize stem and leaf tissues. Maize seedlings (var. Nithyashree) were inoculated with conidial suspensions and were examined for endophytic establishment in leaf and stems at different intervals during 15-90 days after treatment. All six isolates showed colonization in stem and leaf tissues with varying abilities of colonization and persistence. The mean percent colonization ranged from 7.41 to 20.37 % in older stem tissues and 3.70 to 21.29 % in young stem tissues and in leaf, it ranged from 6.46 to 27.78 % in older leaf tissues and 11.11 to 26.85 % in young leaf tissues. Among six isolates tested, Bb-23 isolate recorded the maximum mean colonization in older stem (20.37 %), older leaf (27.78 %) and in young stem (21.29 %). Bb-5a isolate showed maximum mean colonization in young leaf tissues (26.85 %). Persistence of inoculated fungal isolates decreased with increase in age of the plant. No physical symptoms of damage were observed in any of the B. bassiana treated plants. No colonization of B. bassiana was observed in the untreated control maize plants. The results obtained in plating and PCR techniques were similar with regard to the confirmation of endophytic establishment of B. bassiana. This study indicated the possibility of using B. bassiana as an endophyte in maize for management of maize stem borer, Chilo partellus.