1Centre for Plant Molecular Biology and Biotechnology, Tamil Nadu Agricultural University, Coimbatore641003, Tamil Nadu, India
Department of Agricultural Entomology, Centre for Plant Protection Studies
*Email: sridevivetri.2109@gmail.com (corresponding author)
Online Published on 6 February, 2023.
Successful usage of entomopathogenic fungi for pest control under field conditions includes delivery techniques, infectivity and persistence of their inoculum in the environment. Pathogenicity tests performed with oil-based formulation of Beauveria bassiana (Bals.) Vuill (Bb 112) against onion thrips Thrips tabaci Lindeman revealed maximum virulence with the least LC50 and LT50 values of 1.25 x 105 spores/ml and 76.11 hr, respectively. Microplot trials showed oil-based formulation of Bb 112 was effective against T. tabaci when sprayed with Controlled Droplet Applicator (CDA) sprayer giving maximum cumulative reduction of 54.04%. Field experiments revealed oil-based formulation of Bb 112 @ 108 spores ml/l applied with CDA sprayer led to maximum cumulative reduction in thrips incidence (44.69 and 41.01%, respectively), at Kumarapalayam village, Coimbatore and Ambilikkai village, Dindigul districts. In addition, maximum onion yield of 14.66 and 16.23 t/ha was observed at Kumarapalayam and Ambilikkai, respectively. Mycoinsecticides applied with the CDA sprayer can be incorporated in management of T. tabaci.
Onion, Thrips tabaci, Beauveria bassiana, Oil-based formulation, Bb 112, Pathogenicity, Delivery techniques, Infectivity, Persistence, CDA sprayer, LC50, LT50, Bulb yield
