| 摘要 |
<p>Agent for control of stinging mosquitoes (Culicidae) comprises either a soln. of vegetable lecithin (I) in an ecologically acceptable, water-immiscible solvent of high spreading power, or (I) adsorbed onto an acceptable, water-soluble carrier. When applied to the water in which the mosquitoes breed a thin film of (I) is formed on the surface (I) is pref. derived from soya beans and (II) may comprise >90, esp. >98% of an isoparaffin, or is a straight-chain paraffin. Pref. The wt. ratio (I):(II) is 1:0.5-10, esp. 1:1-3, and (I):(III) is 1:1-10, esp. 1:2-5. Suitably the agent is applied at 0.1-10 1. or kg. per hectare of water surface area. Film of (I) denies the mosquito pupae and larvae access to the air and controls them selectively without much effect on aquatic plants, young fish etc. When applied in these forms relatively cheap vegetable lecithins, which do not normally form thin layers, can be used instead of animal lecithins.</p> |
