Please use this identifier to cite or link to this item: http://krishikosh.egranth.ac.in/handle/1/5810038987
Authors: VIVEK V. UPPAR
Advisor: Dr. B. S. NANDIHALLI
Title: EVALUATION OF DIFFERENT MANAGEMENT STRATEGIES AGAINST THRIPS IN Bt COTTON
Publisher: University of Agricultural Sciences, Dharwad
Language: en
Type: Thesis
Agrotags: null
Keywords: EVALUATION OF DIFFERENT MANAGEMENT STRATEGIES AGAINST THRIPS IN Bt COTTON
Abstract: Investigations on population dynamics, dates of sowing, molecular diversity, performance of sticky colour traps, screening of Bt cotton genotypes and bioassay of neonicotioid group of insecticides in the management of cotton thrips, Thrips tabaci (L.) were carried out at ARS, Dharwad during 2012-13 and 2013-14. The peak activity of thrips commenced during 27th Meteorological Standard Week (MSW) and attained relatively more activity at 42nd MSW. MRC-7351 and Chiranjivi recorded least mean thrips as compared to other five genotypes. The influence of five dates of sowing on pest incidence revealed that cotton crop sown during 1st fortnight of June registered lower incidence of pest followed by 2nd fortnight of June and 1st fortnight of July. Cytochrome oxidase subunit I (COI) gene sequences of thrips population from Dharwad and Belgaum districts of northern Karnataka were confirmed as Thrips tabaci COI gene with (88 per cent) homology, while Scirtothrips dorsalis COI gene sequences of Gulberga and Raichur populations showed 91 per cent homology with NCBI published sequence. Among screening of 25 genotypes, Chiranjivi and MRC-7351 were tolerant and RCH-708, Kashinath, RCH-530 and DCH-32 were highly susceptible. With respect to morphological and biochemical parameters MRC-7351 and Chiranjivi had higher trichome density, trichome length, lamina thickness, gossypol glands, total chlorophyll, phenols and gossypol than susceptible genotypes. White colour traps were found to be superior in recording more number of thrips followed by yellow and light blue colour traps. The traps kept at the crop height recorded more number of thrips. The order of toxicity of neonicotinoid group of insecticides against thrips under laboratory, was clothianidin>thiacloprid>acetamiprid>thiamethoxam>imidacloprid. In field experiment, diafenthiuron 50 WP @0.75 g/l was significantly superior in reducing the thrips with highest yield (27.93) and B:C ratio (2.79) which was followed by thiacloprid 40% SC, fipronil 5% SC and thiamethoxam 25 WDG.
Subject: Agricultural Entomology
Theme: EVALUATION OF DIFFERENT MANAGEMENT STRATEGIES AGAINST THRIPS IN Bt COTTON
These Type: Ph.D
Issue Date: 2014-09
Appears in Collections:Thesis

Files in This Item:
File Description SizeFormat 
Th11047.pdfEVALUATION OF DIFFERENT MANAGEMENT STRATEGIES AGAINST THRIPS IN Bt COTTON1.59 MBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.