“BIOEFFICACY, DISSIPATION AND DECONTAMINATION STUDIES OF SELECTED PESTICIDES IN OKRA.”
| dc.contributor.advisor | KAVITHA, K | |
| dc.contributor.author | VENKATESH, T | |
| dc.date.accessioned | 2021-09-23T05:31:54Z | |
| dc.date.available | 2021-09-23T05:31:54Z | |
| dc.date.issued | 2019 | |
| dc.description.abstract | The study entitled “Bio efficacy, dissipation and decontamination studies of selected pesticides in okra” was conducted during kharif 2016-17. The field studies on the efficacy of seven insecticides viz., lambda cyhalothrin 5% EC @ 15 g a.i ha-1, oxymatrine 0.5 % EC @ 1500 ppm, thiamethoxam 25% WG @ 50 g a.i. ha-1, spiromesifen 22.9% SC @ 120 g a.i ha-1, emamectin benzoate 5% SG @ 12.5 g a.i ha-1, spirotetramat 150 OD @ 60 g a.i. ha-1 and thiacloprid 21.7% SC @ 180 g a.i ha-1 were evaluated against major insect pests of okra viz., Amrasca biguttula biguttula Ishida, Bemisia tabaci Gennadius and Earias vitella Fabricius at Student’s farm, College of Agriculture, Rajendranagar, Hyderabad. Whereas, studies on dissipation pattern and decontamination methods of three effective insecticides viz., emamectin benzoate 5% SG @ 12.5 g a.i ha-1, thiamethoxam 25% WG @ 50 g a.i ha-1 and spiromesifen 22.9% SC @ 120 g a.i ha-1 were carried out at All India Network Project on Pesticide Residues, PJTSAU, Rajendranagar, Hyderabad during kharif 2016-17. Among different insecticides evaluated against leafhoppers, thiamethoxam 25% WG @ 50 g a.i. ha-1 was found to be most effective recording least mean number of hoppers of 1.75 and 1.06/ 3 leaves/plant after first and second spray and was significantly superior over other treatments. The next effective treatments followed were thiacloprid 21.7%SC @ 180 g a.i. ha-1, (2.05 and 1.27 leafhoppers/ 3 leaves/plant), lambda cyhalothrin 5% EC @ 15 g a.i. ha-1 (2.23 and 1.50 leafhoppers/3 leaves/plant) and oxymatrine 0.5% EC @ 1500 ppm (2.89 and 2.20 leafhoppers/3 leaves/plant) after ten days after first and second spray respectively. Of various insecticides evaluated against whiteflies, spiromesifen 22.9 % SC @ 120 g a.i. ha-1 was found to be most effective recording 1.64 and 1.17 mean number of whiteflies/3 leaves after first and second spray and was followed by thiacloprid 21.7% SC @ 180 g ai/ha, spirotetramat 150 OD @ 60 g ai/ha and thiamethoxam 25 WG at 50 g ai/ha with mean number of 1.77, 1.36; 1.92, 1.50 and 2.21, 1.70 whiteflies/3 leaves/ plant ten days after first and second spray respectively. Least shoot and fruit borer percent infestation in fruits on number basis ten days after first and second spray was recorded in emamectin benzoate 5% SG @ 12.5 g ai/ha and lambda cyhalothrin 5% EC @ 15 g ai/ha (10.74, 8.52 and 14.08, 10.05) followed by oxymatrine 0.5% EC @ 1500 ppm (17.29, 17.53%) and thiacloprid 21.7 % SC @ 180 g ai/ha (20.22, 20.30%) respectively. Emamectin benzoate 5% SG @ 12.5 g ai/ha and lambda cyhalothrin 5% EC @ 15 g ai/ha found to be most effective in recording lowest fruit borer infestation per cent on weight basis (9.30, 8.61% and 12.70, 9.97%) followed by oxymatrine 0.5% EC @ 1500 ppm (18.90, 25.05%) and thiacloprid 21.7 % SC @180 g ai/ha (23.40, 29.53%) with lowest fruit borer infestation per cent on weight basis ten days after first and second spray respectively. Highest okra fruit yield was recorded from emamectin benzoate 5% SG @ 12.5 g ai/ha treated plot (940.54 q/ha) followed by lambda cyhalothrin 5 % EC @ 15 g ai/ha (770.24 q/ha). The highest net profit in rupees per hectare was achieved from the treatment emamectin benzoate 5% SG @ 12.5 g ai/ha (12, 272.3) followed by lambda cyhalothrin 5 % EC @ 5 g ai/ha (10, 073.3) but the highest incremental cost benefit ratio was obtained in the treatment lambda cyhalothrin 5 % EC @ 15 g ai/ha (1:4.34) followed by emamectin benzoate 5% SG @ 12.5 g ai/ha (1:2.35). Initial deposits of emamectin benzoate 5% SG @ 12.5 g ai/ha, thiamethoxam 25% WG @ 50 g ai/ha and spiromesifen 22.9% SC @ 120 g ai/ha in okra fruits after two sprays were 1.804, 0.263 and 0.180 mg/kg respectively which dissipated to less than limit of quantitation of 0.05 mg/kg at 15, 10 and 5 days respectively with half life’s and waiting periods of 2.48 and 6.03 days for emamectin benzoate; 1.206 and 8.5 days for thiamethoxam and 2.478 and 6.027 days for spiromesifen respectively. With regard to effective decontamination method, for removal of the selective insecticides was recorded from the treatment, cooking in pressure cooker for 10 min ranged between 96.02 to 98.08 per cent while least effective decontamination was 4% acetic acid for emamectin benzoate and spiromesifen (68.79% and 10.66%) whereas for thiamethoxam tap water wash found to be least effective (22.79%). | en_US |
| dc.identifier.citation | D10,481 | en_US |
| dc.identifier.uri | https://krishikosh.egranth.ac.in/handle/1/5810176102 | |
| dc.keywords | “BIOEFFICACY, DISSIPATION AND DECONTAMINATION STUDIES OF SELECTED PESTICIDES IN OKRA.” | en_US |
| dc.language.iso | English | en_US |
| dc.publisher | Professor Jayashankar Telangana State Agricultural University | en_US |
| dc.sub | Entomology | en_US |
| dc.theme | M.Sc | en_US |
| dc.these.type | M.Sc | en_US |
| dc.title | “BIOEFFICACY, DISSIPATION AND DECONTAMINATION STUDIES OF SELECTED PESTICIDES IN OKRA.” | en_US |
| dc.type | Thesis | en_US |
Files
Original bundle
1 - 1 of 1
No Thumbnail Available
- Name:
- final thesis pdf.pdf
- Size:
- 3.5 MB
- Format:
- Adobe Portable Document Format
- Description:
- “BIOEFFICACY, DISSIPATION AND DECONTAMINATION STUDIES OF SELECTED PESTICIDES IN OKRA.”
License bundle
1 - 1 of 1
No Thumbnail Available
- Name:
- license.txt
- Size:
- 1.71 KB
- Format:
- Item-specific license agreed upon to submission
- Description: