The main species are rice leaf-cutting borer, gray-winged night moth, twill night moth and so on. From the perspective of years of practice, under the premise of prevention first and comprehensive prevention and control, chemical prevention and control should dominate.
1. Rice leaf-cutting borer: occurs in 5-6 generations per year, overwintering in thin cocoons with old mature larvae or pupae. The 2nd and 3rd generation calendars last 1 month, the 4th generation calendar lasts 1 and a half months, and the 5th generation calendar lasts 2 months. The larvae are 5-6 years old and the pre-pupal stage is 1 d. Adults are feathered after 10 p.m. to the early morning of the next day, rarely active during the day, and begin to look for spawning sites at night, most of the eggs are in clumps, a few are scattered, the egg blocks are arranged slightly oval, some are arranged in rows, mostly hatched in the morning, and the hatching is relatively neat. After hatching, the young larvae crawl towards the centripetal lobe and lurk in it for harm, and at 3 to 4 years old, they turn to the base of the lawn for harm, but they eat in the morning and evening, and they can eat all day on rainy days for harm. After the larvae mature, the worm dung and broken leaves are mixed together, and the spit is adhered to the base of the lawn to form a cocoon to pupate.
2. Grey-winged night moth: occurs 5-6 generations per year, overwintering in mature larvae or pupae soil. The larvae are pseudo-dead, and the body color varies greatly, from blue-green to dark brown, mostly 6 years old, and the bodies of 1st to 3rd instars are mostly bluish green, and the valve line is purple-red. From the age of 3, each segment of the abdomen has a black brow-like spot on the outside of the sub-dorsal line, each spot is of equal size, the ventral surface of the body is green, no pattern, and the body becomes dark green or gray-black at the age of 5 to 6 years. 1 to 3 year old larvae eat leaves into a lack of moments, and 5 to 6 years old eat a sharp increase, which is the main harm period. Mature larvae pupate 2 to 4 cm under the soil, eggs in chunks, covered with yellow-brown hairs. Adults have strong phototropism, and female moths are not replenished
Eggs can also be laid with nutrients, but the amount of eggs is low.
3, 3 Twill moth
Twill moth is a thermophilic pest, the juvenile name twill moth, the development of moderate temperature in 28 ~ 30 °C, every year from July to September is the peak period. Multi-generational occurrence occurs in 1 year, and the old mature larvae pupate under the soil of 3 to 7 cm. Adult insects have strong flight power, strong tendency to black light, inactive during the day, hiding in the roots of plants or soil cracks and other hidden places, after dusk began to move, feeding, spawning, eggs into blocks, covered with yellow and white villi, more productive on the back of the leaves, the average lifespan of adults is 7 to 15 days. The insect has a wide range of feeding properties, with larvae to harm the leaves of the plant, 1st and 2nd instar larvae nibble on the leaf epidermis and leaf flesh, only the upper epidermis and leaf veins are window-shaped, after 4 years of age into the binge eating period, the leaf only leaves the veins, when the plant is severe, the plant can be eaten, after the 4th instar larvae appear backlit, hiding in the shade on sunny days rarely active, crawling out in the evening to eat, hiding at dawn, but there are also a few larvae out of the rainy day.
Scientific prevention and control measures: planting or introducing excellent turf varieties suitable for local climate growth, studying the occurrence of major lawn diseases and insect pests, strengthening fertilizer management, improving the quality of pruning, timely application of lawn growth inhibitors, creating an environment conducive to the growth and development of lawn varieties, improving the resistance of lawn varieties, and not conducive to the growth and development of lawn diseases and insect pests, is the basis for the comprehensive management of major lawn diseases and insect pests, on the basis of improving garden cultivation and management technology, timely and effective chemical control measures are taken.
1) Before the arrival of the high temperature season (late June), heavy application of phosphorus and potassium fertilizer, light application of nitrogen fertilizer, combined with the use of lawn growth inhibitors, so that the lawn growth is robust and has strong stress resistance.
2) Strengthen fertilizer water management, improve the quality of fertilizer water management, and use decomposed organic fertilizer. Summer temperatures are high, the amount of lawn evaporation is large, and water must be sprayed or watered in time.
3) Trim at the right time. The height of lawn pruning is 4 to 6 cm, which can improve the growth and quality of the lawn to enhance the insect resistance, disease resistance and heat resistance of the grass.
4) Reduce the source of infection. Removing dry grass debris can not only reduce the source of infection, but also facilitate ventilation and water permeability, so that the lawn grows robustly and improves disease resistance.
5) Chemical control. Strengthen the prediction and prediction of major pests and diseases and integrated management, with forecasting and prevention as the mainstay. The first is to spray 15% rust rather wettable powder 1 000 times liquid at the beginning of rust. Or 25% powder rust 1 500 times liquid, the effect of more than 93%, the efficacy is maintained at 1 and a half months. The second is the prevention and control of brown spot disease, putrefaction, leaf blight, etc., which can be sprayed with 65% Daisen zinc wettable powder 500 times liquid or Daisen manganese 700 times liquid, during the onset of the disease 7 to 10 days spray 1 time, continuous spray 3 to 4 times can basically control the occurrence of the disease. The third is to control lepidopteran larvae such as rice leaf-cutting borer, gray-winged night moth, and twill moth. Based on projected forecasts and population density surveys, it should be controlled in time with 50 per cent octathion water spray in late August and mid-September and early October, or 2. 5% cypermethrin emulsion 2,000 times liquid spray can effectively control pests such as rice leaf-cutting borer, gray-winged night moth, twill night moth and so on.