Control of rice diseases and insect pests: how to control rice whitefly?

How to control rice whitefly? What are the hazards of rice whitefly? How does rice whitefly happen? Please introduce the harm of rice whitefly: Rice whitefly, also known as rice whitefly, is a new pest on rice. In addition, it harms food crops such as sugarcane and corn, as well as gramineous plants such as Artemisia mandshurica, paspalum grass, and so on. The nymphs suck the sap of rice leaves with needles, resulting in blackening, wilt and mildew of rice leaves or soot disease. The length of female adult of rice whitefly is about 0.71mm, and that of male is about 0.64mm. After 5-6 days, white wax powder is secreted from the body and wing surface of the first emergence adult. The first instar nymph has long 0.29mm, 3 pairs of chest feet, well developed antennae, light yellowish green, flat oval body, 18 pairs of external bristles, and the anterior and posterior bristles are thicker and longer than those on both sides, and the antennae and feet degenerate after entering the second instar. Body length 0.34mm and 0.57mm of the second and third instar nymphs. The pupal shell is about 0.92mm long, wide 0.38mm, oval, with 4-6 spiny hairs at the dorsal and anterior ends, mostly 4, with "upper" molting lines, and 4 spiny hairs at the posterior end. The occurrence period and causes of rice whitefly: when the temperature of rice whitefly rises to 16 ℃ in mid-late April, adults appear in the early sowing seedling field. The first-fourth generation is harmful to double-cropping early rice, and the third generation is the main harmful generation. The average temperature is 26.8 ℃, the relative humidity is 72%, the egg stage is 9-12 days, the first instar nymph is 2-3 days, the second instar is 3-5 days, the third instar is 4-6 days, the pupae is 6-8 days, the adult pre-oviposition period is 1-2 days, and the adult life span is 9-21 days. 3-6 generations are harmful to single cropping mid-season rice, and 4-5 generations are the main damage generations. The 5-6 generations were harmful to double-cropping late rice, and the fifth generation was the main one. Generations overlap between 3 and 5 generations. The damage was heavy from booting to filling stage. The paddy field irrigation in deep water, many weeds, partial application of nitrogen fertilizer, luxuriant plant growth, ineffective tillers and poor ventilation were the most serious. From July to August, high temperature and drought suffered heavily. Rice whitefly control methods: (1) strengthen field management: timely removal of weeds on the edge of the field and ditch, timely ploughing and falling of grain seedlings, elimination of overwintering insect sources; reasonable close planting; fertilizer and water management to avoid partial application of nitrogen fertilizer, prevent deep irrigation, timely roast the field, control ineffective tillers. (2) Protection and utilization of natural enemies: reduce the number of times of pesticide application, use low toxic pesticides as far as possible, and protect natural enemies. (3) Chemical prevention and treatment: the strategy of pressing before and after controlling insects was adopted to treat 3-5 generations ruthlessly. In the peak period of the occurrence of young nymphs, spray 1000 times of 25% buprofezin wettable powder or 40% omethoate EC 1000 times, 8% insecticidal wettable powder 1500 times, 20% methamphetamine EC 1000 times, 44% Sukai EC 1500 times, 20% imidacloprid (Kangfudo) concentrated solvent 3000-4000 times. Commonly used agents are chlorpromazine, omethoate, aldicarb, methotrexate, sukai and imidacloprid. Click to get more rice planting techniques click to get more food crop planting techniques