International Journal of Pure & Applied Bioscience (IJPAB)
Year : 2017, Volume : 5, Issue : 1
First page : (195) Last page : (201)
Article doi: http://dx.doi.org/10.18782/2320-7051.2445
Survey and Efficacy of Certain Newer Insecticides against Sucking Insect Pests of Bt Cotton
K. Indirakumar1*, P. Karthik, and N. Raju2
1Assistant Professor,Thanthai Roever Institute of Agriculture and Rural Development
2Senior Professsor and Head, Thanthai Roever Institute of Agriculture and Rural Development, Perambalur- 621 115
*Corresponding Author E-mail: poochimb@gmail.com
Received: 12.01.2017 | Revised: 24.01.2017 | Accepted: 25.01.2017
ABSTRACT
A survey conducted in 10 villages in Perambalur district showed that the incidence of sucking pests in Bt cotton had its changing scenario. The mean population of thrips in Bt cotton was high in the early vegetative stage with 10.84 per leaf . The mean population of aphids were high with a value of 7.17 per leaf when the crop was 30-35 days old. The population of leaf hoppers were low during the early stages and it increased when the crop was in maximum vegetative stage. The mean population of leafhopper was 4.32 per leaf and many fields showed the typical symptoms of hopper burn. The whitefly population was low during the early stages of the crop with the mean population of whitefly 2.81 per leaf and was very high during the maximum vegetative stages of the crop. The typical symptoms of upward curling and yellowing of the leaves was very high in Vallapuram area, when the crop was about 75-80 days after sowing. An evaluation of new molecules compatible with IPM shows the most significant treatment in controlling the leafhopper were imidacloprid@ 60 g a.i. ha-1 which has reduced the population to about 64% ; thiomethoxam @ 450 g a.i. ha-1 hreduced the whiteflies to 75% and acetamaprid45 g a.i. ha-1 reduced the aphids to 89 %,. The benefit cost ratio of the new molecule Imidacloprid was 1:2.5 followed by Thiomethoxan and Acetamaprid with 1:20 and 1:2.10 respectively besides being effective in checking the three sucking pests leaf hopper, white fly and aphids.
Key words: Sucking Insect Pests, Bt cotton, Survey of insect pests, Efficacy of newer insecticides and cost benefit ratio
Full Text : PDF; Journal doi : http://dx.doi.org/10.18782
Cite this article: Indirakumar, K., Karthik, P. and Raju, N., Survey and Efficacy of Certain Newer Insecticides against Sucking Insect Pests of Bt Cotton, Int. J. Pure App. Biosci.5(1): 195-201 (2017). doi: http://dx.doi.org/10.18782/2320-7051.2445
