Please use this identifier to cite or link to this item:
|Authors:||Deore Bhaidas V.|
|Title:||ASSESSMENT OF INSECTICIDE RESISTANCE IN DIAMONDBACK MOTH (Plutella xylostella L.) ON CABBAGE|
|Publisher:||Mahatma Phule Krishi Vidyapeeth, Rahuri.|
|Abstract:||Investigations on assessment of insecticide resistance in diamondback moth, Plutella xylostella, Linnaeus on cabbage were undertaken at Department of Agricultural Entomology, Post Graduate Institute, MPKV, Rahuri during 2011-2013. Insecticide usage pattern in Ahmednagar, Dhule, Pune and Nashik locations against diamondback moth on cabbage was also studied. Survey results indicated that farmers relied mostly on chemical insecticides to control the diamondback moth on cabbage. The insecticides viz., chlorpyriphos, quinalphos, profenophos, cypermethrin, lambda-cyhalothrin, flubendiamide and chlorantraniliprole were the most widely used for its control. It was also observed that the most cabbage growers from all four locations followed routine or calendar spraying pattern. Majority of the farmers did sprayings at an interval of 6 to 10 days giving maximum 6 to 8 sprays. Toxicity of certain conventional insecticides against P. xylostella in western Maharashtra was studied. The populations collected from Ahmednagar, Dhule, Nashik and Pune locations were tested using leaf dip technique of bioassay. Based on the LC50 values, cartap hydrochloride was found to be most toxic against DBM population from different locations with LC50 values ranging from 0.3233 to 0.4384 mg a.i. ml.-1 followed by lambda-cyhalothrin and chlorpyriphos with LC50 values of 0.5812 to 0.7179 and 1.1619 to 1.6513 mg a.i. ml-1, respectively. Fenvalerate was found to be least effective against all the field populations with the highest LC50 values ranging from 1.9966 to 2.3478 mg a.i. ml-1 followed by quinalphos with LC50 values ranging from 1.2330 to 1.7351 mg a.i. ml-1. In the present study, P. xylostella population collected from all four locations recorded varied levels of resistance ranged from 3.73 to 104.81-fold. Maximum level of resistance was observed in fenvalerate (89.13-104.81-fold) followed by lambda cyhalothrin (69.19-85.46-fold), quinalphos (38.41-54.05-fold) and chlorpyriphos (21.92-31.16-fold). Very low level of resistance was recorded by cartap hydrochloride (3.73-5.06-fold). Baseline susceptibility studies with newer insecticides were conducted by Potters spray tower method. The results revealed that chlorantraniliprole was highly toxic to P. xylostella with lowest (0.0039 mg a.i. ml-1) LC50 value followed by spinosad, indoxacarb and chlorfenapyr with LC50 values of 0.0119, 0.0348 and 0.0873 mg a.i. ml-1, respectively. Novaluron was the least toxic with highest LC50 value of 0.0921 mg a.i. ml-1. Based on LC50 values, the descending order of toxicity of insecticides was chlorantraniliprole > spinosad > indoxacarb > chlorfenapyr > novaluron. The level of resistance recorded by chlorantraniliprole, spinosad, indoxacarb, chlorfenapyr and novaluron were 3.90, 5.41, 7.73, 12.65 and 16.45-fold, respectively when compared with susceptible strain.|
|Appears in Collections:||Thesis|
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.