10th British Weed Control Conference |
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| Authors: | G W Ivens |
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| Institution: | ARC Weed Research Organization , Begbroke Hill, Yarnton , Oxford , 0X5 1PF |
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| Abstract: | The performance of different spray droplet spectra of cypermethrin from cone nozzles applied to brassica leaves was evaluated by bioassay using Plutella xylostella larvae. A spray droplet spectrum containing small droplets (VMD = 119 μm) caused a significantly higher knockdown and mortality compared to a coarser spray (VMD = 210 μm). No significant difference in the responses was observed when cypermethrin was sprayed over the top of the plants compared to plants sprayed from both sides using either nozzle; but the fine spray consistently gave better knockdown and mortality regardless of spray direction. The results indicated that spray effectiveness of cypermethrin could be improved by using a fine spray nozzle. |
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| Keywords: | Spray droplets cypermethrin brassica Plutella xylostella effectiveness Malaysia |
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