Abstract

                                The emergence of mirid bugs as primary pests in Bt cotton fieldsposes significant challenges to cotton productivity in India. Mirid bugspecies such as Creontiades biseratense (Distant), Campylomma lividaReuter, and Hyalopeplus linefer Walker have gained prominence due tofavourable conditions created by reduced pesticide applications in Btcotton fields. This study focussed on morphological characterization ofmirid bug species complex in Tamil Nadu cotton ecosystem. The studyevaluated the efficacy of seven newer insecticides against the mirid bug,Creontiades biseratense, a significant pest of cotton, in two experimentsconducted at TNAU Cotton Farm, Coimbatore district and Memathur,Virudhachalam, Cuddalore district, during Kharif 2022 and 2023.Treatments included Spinetoram 11.7 SC, Flonicamid 50 WG, Dinotefuran20 SG, Thiamethoxam 25 WG, Clothianidin 50 WG, Imidacloprid 17.8 SLand Acetamiprid 20 SP. Spinetoram demonstrated the highest efficacy,reducing the pest population by 80.83% in Experiment I and 75.07% inExperiment II, followed by Flonicamid and Dinotefuran. Lower efficacywas observed with Imidacloprid and Acetamiprid, with reductionsbelow 60%. Yield and economic analysis highlighted Spinetoram as themost cost-effective treatment, achieving the highest yields (2346 kg/ha in 2022 and 2248 kg/ha in 2023) and cost-benefit ratios (CBR) of2.74 and 2.51, respectively. Flonicamid and Dinotefuran also providedfavourable returns, while traditional neonicotinoids like Imidaclopridexhibited declining performance, likely due to resistance development

Key words : Cotton - Mirid bugs, species diversity, Creontiades biseratense, morphology, environmental correlation, IPM, insecticides