FIELD EFFICACY OF SELECTED BIO-PESTICIDES AND SYNTHETIC INSECTICIDES AGAINST SUCKING PESTS OF COTTON AND THEIR IMPACT ASSESSMENT ON SPIDER

ABSTRACT: The study was carried out to evaluate the efficacy of Toximite 1.8 EC, Ecomec 1.8 EC, Tundra 20 SP, Marshal 20 EC, Dursban 20 EC, Imitaf 20 SL, Haymidor 70 WG against sucking insect pests of cotton. Data regarding sucking pest infestation and prevalence of beneficial insects was recorded days before spray and, 3 and 7 days after spray. The results indicated that at 3 and 7 DAS, Imidacloprid (Haymidor 70 WG) provided the lowest number of jassid per leaf (2.75 and 1.75, respectively) with the highest population reduction (44.85%) over pre-treated population. At 3 and 7 DAS of second spray, the lowest number of jassid per leaf (1.17 and 1.42) was recorded in the Abamectin (biopesticide 1) and Acetamiprid (Tundra 20 SP) treated plot but the highest population reduction (67.56%) over pre-treated population was found in Imidacloprid (Imitaf 20 SL) treated plot. At 3rd spray, the highest population reduction (67.63%) was found in Carbosulfan (Marshal 20 EC) treated plot. The highest per cent reduction (38.19%) of mite infested leaf per plant was found in the Abamectin followed by Imidacloprid (Imitaf 20 SL) (33.33%) treated plot. At 3 DAS of first spray, the lowest number of spiders was recorded from the Imidacloprid (Imitaf 20 SL) (0.08) treated plot, implied that Imidacloprid adversely affect the spider population. The results revealed that the treatment Imidacloprid was identified as the superior and promising insecticide among the treatments against all the sucking pests of cotton followed by Acetamiprid (Tundra 20 SP). Biopesticides as Abamectin (Toximite 1.8 EC) and Azadirachtin (Ecomec 1.8 EC) were found as less toxic against spider compared to other tested insecticides. 

Keywords: Biopesticides, cotton, efficacy, insecticides, sucking pests