In vivo and in vitro assessment of Trichoderma species and Bacillus thuringiensis integration to mitigate insect pests of brinjal (Solanum melongena L.)

Abstract

Abstract The present study was performed to assess the individual and combined potential of 3 different concentrations of Trichoderma sp. (Ts) and Bacillus thuringiensis (Bt) to control brinjal insect pests. Tested formulations were applied on larval and adult stages of the pest. The Trichoderma laboratory bioassays revealed 73% mortality of the aphid species, Aphis gossypii (Glover), and 53% mortality of the cotton leafhopper (Jassids) Amrasca bigutulla bigutulla (Ishida), while opposite results were observed in case of Bt at the highest concentration (1 × 108 cfu ml−1) used. In vivo results revealed that Ts caused a significant population reduction of the aphid (87%) than the jassid (72%), 7 days of post-treatment, at the highest concentration, while non-significant results were observed at the lowest concentrations. A. gossypii was significantly found more susceptible to the mixture of Trichoderma + Bt than the jassid (62%) and brinjal shoot and fruit borer (65%) even after 48 h of treatment application. The combined application (Trichoderma + Bt) showed maximum population reduction of jassid (88%), aphid (95%), and BSFB (96%), respectively, 7 days post-applications. The positive correlation among time and concentration was observed. The result may imply that consortium of these microbial organisms could be effective and can be incorporated in IPM programs for effective control of sucking and chewing insect pests of brinjal.

Keywords

• Brinjal
• Biological control
• Trichoderma spp.
• Bacillus thuringiensis
• IPM
• Insect pests