Friends who grow vegetables are not strangers to small cabbage moths, why do you say so? Mainly because the small cabbage moth is a very common pest, at the same time, it is also known for its difficult control, vegetable farmers have to spend a lot of money every year, time to control it. Here you need to pay attention to whether you have to check whether your own medication has such a problem: in order to prevent and treat it as soon as possible, a large number of drugs are used, and the same drug is used for a long time, although there are many drugs, but the effect is very general, or even ineffective.
Mainly because, this way of spraying, so that the resistance of the small cabbage moth is greatly increased, more and more pesticides, the small cabbage moth does not work, so it will be aggravated every year. Another problem is that long-term irrational use of drugs, while killing and injuring, kills a large number of natural enemies, reduces the control effect of natural enemies on small cabbage moths, resulting in more and more serious insect conditions.
In fact, the small vegetable moth has a strong ability to adapt to temperature, in the range of 10-40 ° C, can grow normally and reproduce, that is to say, spring, summer, autumn and winter all year round, small vegetable moths will occur as a pest. They are often in groups, the newly hatched larvae burrow into the leaf, between the upper epidermis to eat the leaf flesh, forming a small tunnel, at first because the insect body is small, the amount of food is small, so it is difficult to find, as the insect body grows, the larvae begin to nibble on the leaf flesh, leaving only a layer of epidermis. By 3-4 years of age, the larvae can eat the leaves into holes or notches, and in severe cases, the leaves are networked or leave only veins. Especially in the vegetable seedling stage, they like to concentrate on eating vegetable hearts, eating to grow points, affecting the heart, and need to be re-sown when they are serious. In general, autumn is more affected than spring, the climate is dry, and less rain may promote their large outbreaks.
<h1 class = "pgc-h-arrow-right" > the reason why the cabbage moth is so difficult to control, first of all, from the aspect of life habits, we can understand</h1>
Laying eggs are scattered and adults are good at hiding. Adult eggs have a big problem, that is, "do as you please", although there are only 1-2 eggs on a vegetable, but the eggs are not concentrated, very scattered, and the eggs are laid at the base, the veins are recessed, not easy to be washed away. When there are 10 adults in the vegetable field, a large number of larvae will appear and begin to harm the plant. After entering the 2nd instar, the larvae of this period are very active, and they are frightened and twist their back legs while spitting silk to escape. Adults hide behind leaves during the day, lie out at night, and generally move at 7-11 pm, so they are not easy to find during the day.
Miscellaneous food, food materials, strong resistance. When the small vegetable moth eats, the requirements are very low, even if it is yellow leaves and fallen leaves, they can eat and reproduce. Mature larvae are not afraid of cold, not afraid of high temperatures, not afraid of drought, and at the same time, the resistance to pesticides is also very strong, and the same pesticide will be used many times. They have a wide range of adaptations to temperature, 10-40 ° C can survive and develop, even at 0 ° C, adults can survive for 30-50 days, high temperature and dry conditions are conducive to their occurrence.
Adults have a long lifespan and a serious overlap of generations. Generally, in a year, the small vegetable moth can occur 4-6 generations, the adult lifespan of winter and spring is up to 63 days, the summer and autumn are shorter, only 4 = 6 days, in a year to complete an era, the shortest only needs 15-18 days, so it is often possible to see the generation overlap occurs, in a vegetable field, there are adults with larvae, eggs, pupae and so on.
Strong reproductive ability, large number of insect populations. In the case of a suitable environment and sufficient food, a female worm can lay about 200 eggs, and at the highest time, more than 500 is nearly 600 grains. Spring and summer, summer and autumn 2 seasons, the temperature is about 20 or so, it takes 25-28 days to complete an era, when the temperature is above 30, the time is greatly shortened, only need about 15 days, so the cycle repeats, in the short term, the amount of insects is greatly increased, increasing the difficulty of prevention and control.
<h1 class= "pgc-h-arrow-right" > for the control of small cabbage moths, according to the characteristics of the occurrence, prevention should be the mainstay, comprehensive prevention and control work. All along, everyone has been based on chemical drugs, in fact, it should also be combined with agricultural, physical, biological control measures to reduce the harm of small vegetable moths and reduce losses. </h1>
1. Agricultural prevention and control
Insect-resistant varieties can be selected to appropriately advance or postpone the planting time of cruciferous families and avoid the peak period of small cabbage moths. At the same time, maintain a reasonable rotation, do not plant cruciferous flowers all year round, you can rotate cruciferous and melon, eggplant, etc., you can also intercropping leeks, garlic, celery, etc., through crop rotation, intercropping, break the food chain of small vegetable moths, reduce food sources, reduce the breaking of the suitable environment for survival, so that the prevention and control work can be easily a lot. The cruciferous family of rotational intercropping only needs to be controlled at the seedling stage, and generally does not need to be controlled in the middle and late stages. At the same time, after the vegetables are harvested, they must clean the countryside in time, remove the diseased and residual tissues and the weeds around the garden, deep ploughing, break the small vegetable moth overwintering, overselling the summer place, and reducing the number of insect mouths.
2. Physical prevention and control
Adult insects are phototropic and can be booby-trapped with frequency-vibration insecticidal lamps, reducing pesticide use while protecting predators. In addition, the green insect trap board is very attractive to small vegetable moths, and the trapping effect is also very good, hanging 20-25 per acre can control the number of population occurrences. For greenhouse planting, 40 or 60 mesh insect control nets can be set up to block, isolate and cut off the harm of pests entering the shed, lay eggs and reproduce, and reduce the number of insect populations.
3. Biological control
There are more natural enemies of small vegetable moths, among them, the parasitic rate of vegetable moths and small vegetable moth velvet cocoon bees is relatively high, in addition to daily medication to avoid harming natural enemies, conditional can release these natural enemies in the vegetable garden, in order to control the number of small vegetable moths, the more natural enemies, the better the control effect. At the same time, a piece of alfalfa can be planted on the edge of the field to facilitate natural enemies to come to the garden and increase the number of natural enemies.
4. Chemical control
Try to choose low toxicity, high efficiency, low residue chemical pesticides, such as flulingurea, methyl verdix. Cyanogen chloride, carnohydrazide, etc. When spraying, pay attention to comprehensive, in place, to avoid omissions, at the same time, be sure to pay attention to the rotation of agents.
At present, for the control of small cabbage moth, chemical control is still the most effective control measures, when using drugs, we must pay attention to strengthening the protection of natural enemies, avoid using highly toxic agents for prevention and control, so as not to hurt natural enemies. At the same time, we must also pay attention to the combination of agriculture, physics, biological control, the combination of four kinds of control measures, multi-channel, comprehensive prevention and control, so as to effectively control the pest of small vegetable moths.