How to use pesticides correctly? A detailed guide to practical methods

Inorchidsdaily care, applying pesticides is an important part, but because most orchid growers lack a basic understanding of pesticides, here I would like to share a little common knowledge about pesticide use that I have summarized from practice, hoping it will be useful to orchid growers. Based on the comprehensive evaluation of the toxicity of pesticides (technical materials) commonly used in agricultural production (acute oral toxicity, dermal toxicity, chronic toxicity, etc.), they can be divided into three categories: highly toxic, moderately toxic, and low toxicity. 1. Highly toxic pesticides: 3911, Suhua 203, 1605, methyl 1605, 1059, Shamiewang, monocrotophos, phosphamidon, methamidophos, isopropylphos, trithion, omethoate, zinc phosphide, aluminum phosphide, cyanide, carbofuran, fluoroacetamide, white arsenic, chlordimeform, ethylmercury chloride, Sailisan, Kuayangjing, chlorinated lime, pentachlorophenol, dibromochloropropane, 401, etc. 2. Moderately toxic pesticides: fenitrothion, dimethoate, Daofengsan, ethion, phosmet, fenchlorphos, BHC, lindane, toxaphene, chlordane, DDT, carbaryl, Haipuwei, Yechansan, Sumeiwei, Hunmiewei, pirimicarb, fenthion, dichlorvos, pyrethroids, Kewensan, Daowenjing, Dikesong, 402, Fumeishen, Daojiaoqing, Tuijunte, Daisenan, DaisenHuan, 2,4-D, Yamaidi, Duca'an, etc. 3. Low-toxicity pesticides: trichlorfon, malathion, acephate, phoxim, dicofol, carbendazim, thiophanate, captan, zineb, thiram, carboxin, isoprothiolane, fosetyl-aluminum, chlorothalonil, nitrofen, propanil, atrazine, butachlor, alachlor, benthiocarb, MCPA, chlortoluron, diuron, trifluralin, bentazone, dalapon, glyphosate, etc. Highly toxic pesticides can cause poisoning or death even with contact with a very small amount. Although moderately and low-toxicity pesticides are less toxic than highly toxic pesticides, contact with a large amount and delayed rescue can also cause death. Therefore, the use of pesticides must take both economy and safety into account. First, I would like to talk about identifying the quality of pesticides, which is a prerequisite for their effectiveness. Pesticide registration has strict requirements for labels. The label must indicate the product name, pesticide registration certificate number, product standard number, production license number or production approval certificate number, as well as the pesticide's active ingredient, content, weight, product performance, toxicity, uses, method of use, production date, expiry date, precautions, the marker band, and the manufacturer's name, address, postal code; for repackaged products, the repackaging unit must also be indicated. If any one of these items is missing, the product quality should be questioned. Then look at the physical form. For example, wettable powders should be loose powder with no caking or granular feel, emulsifiable concentrates should have no layering, and granules should be uniform in size and consistent in color. After buying pesticides, the following points should be noted during use: Use concentration When spraying with liquid formulations, it is often necessary to use water to prepare or dilute the pesticide to an appropriate concentration. Too high a concentration will cause phytotoxicity and waste, while too low a concentration will be ineffective. For some non-wettable or difficult-to-wet powders, a small amount should first be added and the powder made into a paste, then water added to prepare it; a wetting agent may also be added during preparation. Spraying time If spraying is too late, a large number of pathogens have already invaded the host, and even spraying systemic therapeutic agents will yield little benefit. Based on the pattern of disease occurrence and the situation at the time, pesticide should be sprayed in time for protection before disease occurs or just as it begins. The number of sprays is mainly determined by the length of the pesticide's residual effect period and weather conditions. Spraying quality The spray volume should be appropriate. Too little cannot carefully protect all parts of the plant, while too much wastes pesticide and may even cause phytotoxicity. Spraying requires fine droplets and even application; all parts of the plant that should be protected, including the upper and lower surfaces of leaves, must be sprayed. Pesticide resistance issues Long-term use of a single pesticide (mainly systemic fungicides) will cause pathogens to develop resistance, making the pesticide ineffective. To avoid this problem, different types of pesticides can be used alternately, or systemic fungicides and traditional fungicides can be mixed for use. Safe use Before use, read the instructions for the pesticide carefully. During spraying, pay attention to the precautions for safe pesticide use. Although some may say this is alarmist, most orchid growers cultivate orchids at homegrow orchids, and here I want to remind everyone: those who are weak and frequently ill, those suffering from skin diseases, pesticide poisoning, or other illnesses and who have not yet recovered, and women during breastfeeding, pregnancy, or menstruation, as well as those with unhealed skin injuries, must not spray pesticides or should temporarily stop spraying. When spraying, children must not be brought to the work site. When applying the pesticide, workers should wear anti-toxic masks and long-sleeved tops, long trousers, shoes, and socks. During operation, smoking, drinking water, and eating are prohibited, and hands must not be used to wipe the mouth, face, or eyes; spraying each other for fun is absolutely prohibited. After daily work, before drinking water, smoking, or eating, hands and face must be thoroughly washed with soap and the mouth rinsed. If conditions permit, take a bath. If operators experience symptoms such as headache, dizziness, nausea, or vomiting, they should immediately leave the pesticide application site, take off contaminated clothing, rinse the mouth, wipe and wash the hands, face, and other exposed skin areas, and promptly send the person to the hospital for treatment. Storage methods For homeorchid growingthe quantity is small, and one bottle (packet) of pesticide often has to be used for a year, so storage must be discussed. For leftover pesticides, be sure to pay attention to their shelf life; those that have reached the expiry date should not be stored further. Pesticides must be stored separately in an unused room, and must never be casually left somewhere, especially not together with food, because some liquid pesticides, if the bottle cap is not tightened, can volatilize very easily and contaminate food, causing food poisoning incidents. Pesticides must not be exposed to moisture or sunlight. Pesticides should be placed in a ventilated and dry place. After absorbing moisture, liquid pesticides easily form solid precipitates and become ineffective, while powder pesticides gradually form lumps and deteriorate. At present, the temperature is still relatively high, and pesticides must not be exposed to strong sunlight, as exposure may cause an explosion. Therefore, storing pesticides requires not only moisture and sun protection, but also firmly tightening the inner and outer caps of bottles to prevent volatilization. There are now many imported pesticides on the market. To make it easier for everyone to identify them, their symbol meanings are briefly introduced as follows: SS - water-soluble solvent for seed treatment; LS - solution for seed treatment; FS - suspension concentrate for seed dressing; PS - pesticide for coating seeds; AC - aqueous concentrate; OL - oil miscible liquid; EC - emulsifiable concentrate; DP - dustable powder; FO - micro powder; WP - wettable powder; SP - water-soluble powder; SL - soluble concentrate; VC - ultra-low volume liquid; SV - ultra-low volume suspension; EO - emulsion, water in oil; EW - emulsion, oil in water; PC - percentage concentration; WG - water dispersible granules; MED - minimum effective concentration; MAC - maximum allowable effective amount; SC - suspension concentrate; GR - granule. I hope this short article can offer some inspiration to orchid growers, so that everyone can use pesticides reasonably, safely, and effectively, and let their belovedorchidssuffer fewer diseases or even none at all, and grow healthily. Excerpted from "OrchidBible" Shanghai Yu Junjie