Whiteflies cabbage

Methamidophos is an insecticide and acaricide for control of chewing and sucking insects and spider mites such as aphids, flea beetles, whiteflies, cabbage loopers, thrips, cutworms, Colorado potato beetles, armyworms, mites, leafhoppers, and others on vegetables, cotton, potatoes, and fruits. It has an oral LD50 in rats of 250-500 mg/kg. 

Because some form of brassica crop can be growing at any time of year, cabbage whitefly and mealy aphids can build up in considerable numbers. It pays to remove all members of this crop family once a year—in early spring, for example—to break the cycle. 

Adults of this pest, Vitm (2 mm) long with white wings, fly up from plants when disturbed. Eggs laid on host plants hatch into "scales"—oval, immobile creatures found on the undersides of leaves. Both scales and adults are sap-feeders and excrete sticky honeydew, which drops onto leaves below. Sooty molds (q.v.) develop on this. A severe infestation may stunt growth. See Cabbage whitefly Greenhouse whitefly. 

Protection Offered You can use potato starch dextrin to control aphids, spider mites, thrips, and whiteflies. It also controls powdery mildew on cucumbers. Other uses will likely be recommended once a commercial product reaches the market. Flour is a good control for larger pests like imported cabbage-worms and loopers on cabbage family crops. 

After the treatment, whiteflies were kept with fresh cabbage for egg-iaying. 

Acaricidal and insecticidal activities of the synthesized compounds were determined as follows. In the case of two-spotted spider mite (T. urticae), female adult mites were placed on the excised leaf of kidney bean seedling, and then, the test solution (test confounds were dissolved in acetone at 20 to 200 ppm) was sprayed onto die leaf. Mortality was determined 2 days after the treatment. In the case of western flower thrips (F. occidentalis), first instar larvae were released on released on the excised leaf of kidney bean seedling (15 larvae per a disk), which was then sprayed with the test solutioa Mortality was determined 2 days after the treatment. In die case of silver leaf Miitefly B. argentifolii), adult whiteflies were released on die cabbage leaf and allowed to oviposit for 24 hours. Adults were removed from the leaf and the leaf was stood for 7 days. A leaf disk of 20 millimeters in diameter was excised from the leaf and sprayed with the test solution. Mortality was determined 6 days after the treatment. The acaricidal and insecticidal activities were indicated as activity indexes 3,2 and 1 which represent the mortality of 100%, 99% to 50% and less dian 49%, respectively. 

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