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How to prevent insects from invading rice?
Farmers should prevent mites, rats and mildew when storing rice.

Rice is the first grain crop in China, and its total output accounts for about 40% of the total grain output in China, especially in the middle and lower reaches of the Yangtze River. High temperature, high humidity and abundant rainfall are the climatic characteristics of the middle and lower reaches of the Yangtze River. This climate is suitable for growing rice with a good harvest. During the storage period of rice after harvest, if it is not properly kept, it will cause certain losses to rice due to insect erosion, mouse eating and other reasons. The weight loss of stored rice in some areas can reach 10%. Although rice has a complete shell and has certain resistance to the invasion of insects, mites and molds, if it is not properly kept, stored rice will breed insects, mites and molds, and mice will steal it. There are more than 200 kinds of stored grain pests in China, among which corn weevil is the most serious. Adults are about 3 mm long and reddish brown. There are four yellow spots on the back of the body. The head extends like a trunk, which is called a weevil (Figure 1). It is a typical insect-eaten stored grain pest, which can turn rice into powder in severe cases. Mites are similar to spiders, but different from insects, mites have eight adults (Figure 2) and insects have six adults (Figure 1). Although the body length of mites is less than half a millimeter, they breed rapidly. As long as the climatic conditions are suitable, they can occur in large numbers, which is harmful to stored food and human health. Rats do amazing harm to food. A big mouse eats about 9 kilograms of grain every year. Rats not only steal food, but also urinate in food, which affects food hygiene; Rats can also spread diseases and pose a threat to human health. There are many kinds of mice that harm stored grain, and we often take housefly as its representative species (Figure 3). Mold is a kind of food microorganism. There are many kinds of molds in grain, but Aspergillus and Penicillium are the main ones. Although the mold is very small, when the grain is moldy, we can see that there are gray-white or gray-yellow "hairs" on the grain. This hair is mold. The Aspergillus flavus in Figure 4 is an image seen under a high-power microscope. Mold makes grain moldy, so serious that it can't be eaten or used as feed. This paper introduces several methods to prevent and control insects, mites, rats and molds that harm stored grain. Keep the rice dry-dry rice is the first condition for storage. The safe water content of early indica rice should be below 13%, and that of early and middle japonica rice should be below 14%. Generally, the moisture content of early-middle indica rice can reach or be lower than the safe moisture content after natural drying before storage; However, the original moisture of late japonica rice is high at harvest, so it should be dried in time. This kind of rice with safe moisture content will generally not be moldy during storage. The barn should be closed-rice should be stored in a closed barn where rats can't bite, such as a high-yield barn made of iron. High-efficiency and low-toxicity pesticides-In order to control stored grain pests (mites), high-efficiency and low-toxicity pesticides (stored grain protectants) can be mixed with rice before storage. If 100g phosphorus powder can be mixed with 250kg rice, it can effectively protect rice from insect pests for one year. Using local materials to control pests-Natural substances can be used to control stored-grain pests according to local conditions, such as plants such as calamus and pepper. Mixing plant ash, which accounts for about 30% of the grain weight, with rice can effectively control insects and mites. Rice chaff (chaff) is a white powder with high silicon content after full combustion. When it is mixed with rice, its insecticidal and insect-proof effect is much better than that of plant ash. Diatomite is a natural insecticide for stored grain pests. Mixing it with grain can effectively control stored grain pests. The usual dosage is 1 g per kilogram of grain (1000 g). close