Beet noctuidae, commonly known as blackheads and green worms, belongs to the lepidoptera noctuidae and is the main pest on many crops in summer and autumn. It seriously harms nearly 100 crops such as corn, peanuts, soybeans, cotton, tobacco, flowers, vegetables, and fruit trees. In general, crop yields are reduced by about 15%, and in severe cases, yields can be reduced by 30%-40%, and even more than 75%. The harm is very serious.
Beet nocturnal moth hatching larval conditions
Beet noctuidae larval morphology
First, the characteristics of the hazard
The hatching larvae cluster on the back of the leaf, spit silk knotted net, eat the leaf flesh, leave the epidermis, appear transparent holes, disperse after 3 years of age, eat the leaves into holes or lack of carving, and eat out the leaves when severe, leaving only the leaf veins and petioles, resulting in the death of the vegetable seedlings. Larvae over 3 years old can also drill bell peppers and tomato fruits, drill into onion tubes, corn female ears and other places to harm, and eliminate a large amount of feces, pollute fruits and fruit ears, resulting in fruit fall and rotten fruit.
Beet nocturnal moth infestation
Second, the main points of prevention and control
1, early treatment of small: beet nocturnal moth before the age of 2 years of the weakest drug resistance, is the best period for drug control; after 2 years of age the insect resistance is enhanced, the larger the insect body, the stronger the resistance, the worse the effect of drug control, so when preventing and controlling, in line with the principle of "early treatment of small", early prevention and control.
2. Timely medication: The most effective control method for beet nocturnal moth is pharmacy control. Beet nocturnal moth has the habit of day and night out and strong resistance to drugs, therefore, it should be selected before 8 a.m., or after 6 p.m. when the pest is active on the surface of the vegetable leaf, the drug effect is the best, generally strong sunlight, high temperature should not be used. This is because at this time, the pests have long been lurking in the soil cracks and grasses, and they cannot play a direct contact killing role, and the prevention effect is not obvious.
3, select the right pesticide: the control of beet moth can be used in the following formulas
Formula 1: 3% methyl vitamin salt suspension 2000 times liquid + 20% carnoylhydrazide 1500 times liquid + silicone hypertonic agent;
Formula 2: 20% chlorhexabenzamide suspension 2000 times liquid + silicone hypertonic agent;
Formula 3: 30% insect mite suspension 1000 times liquid + 3.2% methyl vitamin salt. Cyanide emulsion 2000 times liquid;
Formula 4: 3% methyl vitamin salt suspension + 15% indicovir suspension 1000 times liquid.
Special reminder: these several recipes to control the beet moth has a special effect, the use should be rotated, generally should be sprayed from the early stage of pest occurrence, every 7--10 days, spray 2--3 times. At the same time, the spray should be even and meticulous, so that it is turned up and down, and the four sides are penetrated.