What is the effect of the orchid fungicide zineb?

The chemical name of zineb is zinc ethylenebis(dithiocarbamate). It is a broad-spectrum fungicide with good protective action. The pure product is a grayish-white crystal, and the technical grade powder is a pale yellow powder with a slight fishy odor. It is insoluble in water and in most organic solvents, is highly hygroscopic, and easily forms lumps; under sunlight, high temperature, moisture and alkaline conditions it will gradually decompose and lose effectiveness. The formulations include 65% and 80% wettable powders. Treating narcissus or gladiolus bulbs with a 3O0-50O times dilution of the 8O% wettable powder can reduce disease incidence; spraying with a 5OO-8O0 times dilution of the 8O% wettableorchidleaf blight, round spot disease and anthracnose; in addition, it can also control diseases of chrysanthemum and various other ornamental flowers. Points to note when using it: (1) It should not be mixed with alkaline agents such as soap, rosin mixture, or lime sulfur; when necessary it may be mixed with Bordeaux mixture, but it must be mixed and used immediately; (2) This product is irritating to human skin, nose and throat, so protective measures should be strengthened. (Liu Zhongjian)