In the strawberry production process, the twill moth is a major pest, this pest is also a powerful role, in the southern region can occur 5-6 generations a year, it mainly uses larvae to mutilate leaves, and sometimes also to harm young buds, flowers, and fruits, often causing serious harm to strawberries.
<h1>1. Hazard characteristics</h1>
Adult twill moths are mainly active at night, and have a tendency towards black light, sweet and sour, and liquor. Eggs are mostly laid on the reverse side of the lower and middle leaves of the plant, so they are generally difficult to detect. The newly hatched larvae eat day and night nearby, and disperse after the 3rd instar, each endangering, and after the 4th instar, as the insect body grows, the amount of food also increases suddenly, and it begins to overeat, day and night.
After the larva matures, it hides in the shallow soil to pupate. 1-2 instar larvae nibble on the epidermis and leaf flesh of the leaf, leaving only the epidermis and leaf veins like window screens, the 3-year-old larvae disperse as pests, bite the leaves, leaving only the main vein, they are very cunning, will pretend to die, afraid of the sun, hide in the dark strawberry base or soil cracks when the weather is sunny, so it is generally not easy to see the larvae during the day, and at night it will come out of harm, take nectar on the flowering plant, and then lay eggs.
<h1>2. Factors of occurrence</h1>
(1) A large number of insect sources in the field: brought in by strawberry seedlings, residual crops on the stubble, and migration of nearby crops or weeds, etc., provide a strong basis for the occurrence of insect pests, and once the environment is suitable, hatching hazards will begin.
(2) The temperature suitable for the development of each insect state is 28-32 ° C, but even at a high temperature of 33-40 ° C, they can live normally, like high temperature, arid environment, high temperature in summer and autumn, drought, very suitable for the ecological development of pests.
(3) The feeding habits of pests are relatively mixed, and in recent years, with the increase of vegetable area, especially anti-seasonal vegetables, such as cowpeas, cauliflower, greens, etc., the food is rich, which is conducive to the reproduction and growth of pests. Strawberry fields are surrounded by unplanned open spaces, wastelands, and also facilitate the occurrence of pests.
(4) When controlling diseases and insect pests, natural enemies are killed, the number of natural enemies is small, and there is no natural enemy control, so that pests exist and occur in large quantities.
<h1>3. Prevention and control measures</h1>
(1) Agricultural control
Before colonization, plough the soil, eliminate some of the larvae and pupae, reduce the number of pests; after the harvest of the last crop, whether it is strawberries or not, we must carry out a comprehensive garden clearance activity, remove the residue of the field disease, the surrounding weeds, reduce the number of germs, and break the egg site; the pests are very strong in sweet and sour liquid, like laying eggs on tall, honey source plants, like soybeans, corn, sunflowers, etc. We can plant these crops near the strawberry garden, attract pests to lay eggs and feed, thereby reducing the egg production on strawberries and reducing the harm.
(2) Artificial hunting
During agricultural operations, the leaf back is examined, the egg blocks and leaves with larvae are removed, and the older larvae are artificially killed. Greenhouse planting, in and out of the shed door at will, to avoid the outside adult insects to take the opportunity to move into the shed, once the harmful insects are found, timely open the soil to catch insects.
(3) Physical prevention and control
Adult pests have strong phototaxis and sweet and sour properties, in the adult occurrence period, with black light lamps, frequency vibration insecticidal lamps, sweet and sour liquid for night booby traps, reduce the number of adult insects, reduce the harm.
(4) Chemical control
At the peak of egg hatching, or the peak of 2-year-old larvae, pay attention to the field, and when there are 2-3 nests of larvae per acre, it can be controlled. According to the characteristics of diurnal and nocturnal outflow, the medication time is after 6 p.m. to obtain the best prevention and control effect. Spray 1 drug every 8 days, spray 2-3 times in a row, can be used agrodi music, or Taibao and so on. For Mitsubishi, it is possible to configure poisonous material and spread it on the foliage or ground of the plant in the evening.