Compatibility of entomopathogenic fungi and Azadirachta indica extract against the cotton pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) under controlled conditions

Abstract

Abstract Compatibility of entomopathogenic fungi (EPFs) viz. Verticillium lecanii, Metarhizium anisopliae and Beauveria bassiana with Azadirachta indica extract (alone and in combinations) was evaluated against 2nd instar larvae of the cotton pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) under controlled conditions. Results indicated that maximum mortality rate of P. gossypiella larvae was recorded at combination of the highest conidial concentrations of V. lecanii + M. anisopliae + B. bassiana along with A. indica extract, while minimum mortality rate was recorded at A. indica extract alone, 12 days post exposure interval. Maximum mycosis and sporulation from dead cadavers of P. gossypiella larvae were recorded at the highest concentration of B. bassiana, while the lowest mycosis and sporulation were recorded at the highest conidial concentrations of V. lecanii + M. anisopliae + B. bassiana along with A. indica extract. Maximum percent of pupation and adult emergence in P. gossypiella larvae was observed in the treatment, where A. indica extract was applied alone, while the minimum percent of pupation and adult emergence was observed at the treatment combination of the highest concentration of B. bassiana + V. lecanii + M. anisopliae along with A. indica extract was applied. EPFs proved their enhanced long-term protection potential for cotton crop against P. gossypiella. A. indica extract integrated with the EPFs can be a potential alternative to the chemicals and as an effective component of IPM program against P. gossypiella.

Keywords

• Cotton pink bollworm
• Pectinophora gossypiella
• Entomopathogenic fungi
• Azadirachta indica
• Virulence
• Biological control