Efficacy of <I>Trichogramma chilonis</I> Ishii in Combination with Biopesticides against <I>Helicoverpa armigera </I>(Hubner) in Rainfed Cotton Ecosystem

N. Balakrishnan; R. K. Murali Baskaran; N. R. Mahadevan

doi:10.18311/jbc/2004/4078

Jump To References Section

Authors

N. Balakrishnan
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore 641 003, Tamil Nadu ,IN
R. K. Murali Baskaran
Department of Agricultural Entomology, Agricultural College and Research Institute (TNAU), Madurai 625 104, Tamil Nadu ,IN
N. R. Mahadevan
Department of Agricultural Entomology, Agricultural College and Research Institute (TNAU), Madurai 625 104, Tamil Nadu ,IN

DOI:

https://doi.org/10.18311/jbc/2004/4078

Keywords:

Biopesticides, Efficacy, Helicoverpa armigera, Trichogramma chilonis.

Abstract

A study was undertaken to observe the combined effects of Trichogramma chilonis with some biopesticides viz., HaNPV, Bacillus thuringiensis var. kurstaki (HaIt WP) and Beauveria bassiana (Bev Bas). Two releases of T. chilonis with two sprays of B.t.k. recorded less mean larval popUlation (O.33/plant). less damage on shed squares (42.78%), intact squares (9.12%), bolls (14.20%) and loculi (10.68%) and recorded higher yield (782 kg/ha). Two releases of T. chilonis with two sprays of HaNPV was the next best treatment regarding less mean larval popUlation and damage on fruiting parts. Application of B. bassiana alone and in conjunction with T. chilonis proved less effective compared to other treatments. Two releases of T. chilonis with one spray of B.t.k or HaNPV and T. chilonis alone performed moderately in reducing the larval population and damage on fruiting parts.