Evaluation of Lysinibacillus formulations against banana pseudostem weevil (BPW) Odoiporus longicollis [Olivier.]

Abstract

ABSTRACT Odoiporus longicollis [Olivier], commonly known as banana pseudostem weevil or BPW has been a predominant pest of bananas, resulting in devastating losses in banana cultivation across India. The current research explores the use and effectiveness of the microbial biopesticide – Lysinibacillus sphaericus against banana pseudostem weevils in field and laboratory conditions. The LC50 value of L.sphaericus was found to be 9.92% of 1 OD (optical density at 600 nm) culture after 24 h of treatment against grubs at in-vitro conditions. L.sphaericus cultures were formulated as liquid, solid, and capsule formulations, and analysed parameters such as viability, shelf life, and pest control efficiency against banana pseudostem weevils. The capsule-based formulation (8 ± 2 × 102a CFU/ml) was most effective against the grubs with a storage period of 120 days to six months under room temperature in air-free containers. The efficacy of a capsule-based formulation at in vivo conditions in the pseudostem revealed that the gelatine coat of the capsule disintegrated within 24hrs after application, leading to the easy release of active ingredients to the pseudostem. The field evaluation observed that in L.sphaericus-based capsule formulations treated plants, there was more than an 80% reduction in the infestation of grubs over control treatments. The current paper describes the application of L.sphaericus against the weevil, its unique formulation as a capsule increasing bacterial shelf life, and ease of application. The development of an easily applicable and effective capsule with a better shelf life of 6 months would increase the marketing possibilities of this biopesticide formulation against Odoiporus longicollis.