Studies on insecticide resistance in leafhopper, amrasca biguttula biguttula (ishida) in bt cotton
KrishiKosh
View Archive InfoField | Value | |
Title |
Studies on insecticide resistance in leafhopper, amrasca biguttula biguttula (ishida) in bt cotton
|
|
Creator |
Sagar D.
|
|
Contributor |
R. A. Balikai
|
|
Subject |
Agricultural Entamology
|
|
Description |
Studies on insecticide usage, insecticide resistance and diversity in leafhopper, Amrasca biguttula biguttula (Ishida) across major cotton growing districts of Karnataka and nitrogen induced susceptibility on leafhopper population were under taken at the Department of Agricultural Entomology, College of Agriculture, Dharwad during 2011-2013. The insecticide usage pattern varied greatly between and within the locations indicating no definite insecticide usage pattern among the major cotton growing districts of Karnataka. In all the major cotton growing districts of Karnataka except Mysore, monocrotophos and imidacloprid formulations were the primary choices of insecticides for management of sucking pests in Bt cotton. Among the nine insecticides bioassayed, monocrotophos registered higher LC50 value during both the years followed by imidacloprid, thiamethoxam, acephate and acetamiprid while, the lower LC50 value was registered by fipronil followed by clothianidin. The botanical, azadirachtin 1500 ppm recorded higher LC50 value as compared to other nine insecticides. Leafhopper population of Raichur and Yadgir districts recorded higher LC50 values to almost all insecticides under study, while Mysore district’s leafhopper population recorded lower LC50 values to all insecticides bioassayed. Higher mixed function oxidase enzyme activity was noticed in the leafhopper population of Raichur followed by Yadgir, while lower activity was noticed in Mysore district population. The six district’s leafhopper COI gene sequences were confirmed as A. biguttula biguttula cytochrome oxidase subunit I (COI) gene. COI sequence analysis showed higher similarity among the leafhopper population of major cotton growing districts of Karnataka. The cotton leafhopper population of all the six districts was taxonomically identified as A. biguttula biguttula. The incidence of leafhopper and leaf nitrogen content increased with the increase in the nitrogen dosages. The toxicity results indicated that there was no such striking difference in LC50 values among leafhopper population as influenced by dosages of nitrogen. |
|
Date |
2016-07-26T10:42:49Z
2016-07-26T10:42:49Z 2013 |
|
Type |
Thesis
|
|
Identifier |
http://krishikosh.egranth.ac.in/handle/1/69851
|
|
Format |
application/pdf
|
|
Publisher |
UAS Dharwad
|
|