Derris extract is an insecticide for controlling orchid pests

Derris is a perennial vine in the Fabaceae family, growing in South China and the Fujian and Taiwan regions of China,cultivationThe varieties include Derris elliptica (a trailing type) and Derris malaccensis (an upright type). The active ingredient is rotenone, a pure product in the form of white crystals, tasteless and odorless, insoluble in water, and easily soluble in solvents such as benzene, acetone, and ether. The liquid preparation is brown or brownish. Under the influence of sunlight, air, high temperature, and alkaline substances, it easily decomposes and loses effectiveness. Derris has contact and stomach poison effects, and also a certain repellent effect; it also has a regulating and growth-stimulating effect on plants. It has a broad insecticidal range, no residue, is safe for plants, and has low toxicity to humans and livestock; but it is highly toxic to fish. Formulations: 2.5% and 5% derris extract emulsion, 4% derris powder. Target pests and methods of use: Dilute the 2.5% emulsion with water at 5OO-8OO times and spray to control leafhoppers, aphids, red spider mites, etc. Precautions: 1. It cannot be mixed with alkaline substances. 2. The diluted liquid should be used immediately after preparation and must not be stored. 3. When storing the pesticide, choose a cool, dark place to avoid decomposition and loss of effectiveness. (Liu Zhongjian)