The temperature is getting higher and higher, and the berries are starting to worry about everyone... There are simply too many red spiders, what to do if you can't finish fighting, and if you can't kill them!
Red spiders hurt leaves
Red spiders have a strong reproductive ability, although the main outbreak period is in the spring and autumn, but in fact, red spiders can occur all year round! According to statistics, red spiders can occur for 18 to 30 generations a year!
But more importantly, in addition to hermaphroditic reproduction, the female mites of red spiders can also reproduce alone - that is, they do not need male mites to lay eggs and hatch (solitary reproduction can only hatch male mites, and female mites still need to reproduce from both sexes to complete), and can lay 30 to 60 eggs at a time, which can be said to be particularly reproductive.
Some people kill red spiders, will feel that a certain kind of medicine is good, so for a long time only use one drug to kill red spiders, but killing red spiders only a few days before it broke out again. There are several main reasons for this:
Chemical control is flawed
Chemical control is generally spraying, but have you found that if the spray is not evenly beaten, penetrated, there are some dead corners that have not been hit, then the red spider will spread from the dead corner → leaf back → plants→ the entire ridge is destroyed, the process is as fast as 30 days!
Xiaobian emphasizes here that at present, there is no drug that can kill red spiders at all growth stages at the same time.
There are four main growth stages of red spiders - egg stage, juvenile mite stage, pre-mite stage and post-arakane stage, and there are often several stages of red spiders that coexist on one leaf.
Therefore, if there is no timely spray to kill eggs or larvae before the peak period, it is not enough to wait until the four stages of red spiders in the peak period to "gather", and only one drug is not enough.
Monotherapy increases resistance
The continuous use of a drug will strengthen the resistance of the red spider, and the continuous increase in the amount of drug application will only enhance the resistance of the red spider to this drug, and in the end it will only have less and less effect.
Why is the use of insecticides ineffective? The most fundamental reason is that the red spider, also known as the cinnabar leaf mite, belongs to the true mite leaf mite family, not an insect! Of course, the effect of using insecticides is not good!
Cultivate predators
That is to say, we often say that predatory mites, generally a leaf has a predator mite, which can effectively control the red spider. Chilean small plant mite, courgine blunt mite, California predator mite, pasteurized mite and so on are more commonly used in strawberries.
1. California's new small mite has a large amount of eggs and can be used simultaneously with a variety of pesticides, which is the most suitable for use among the four predatory mites. It is advisable to release 18 California predator mites per strawberry, that is, 6,000 strawberries per acre release 5 to 6 bottles of California new small mites.
2. Chilean small plant mite: release Chilean small plant mite according to 100 heads /㎡, and the defense effect can reach 60% after 14 days. The anti-efficacy at the release of 300 heads/㎡ is already comparable to that of chemical reagents, and the prevention effect of 14 days is as high as 99%. The release in mid-to-early April was ideal.
Different potions are applied at different times, the following are some suggestions from the scholar farmer, but the specific drugs should be selected according to the occurrence of different insect states of red spiders and the resistance level of red spiders in their respective strawberry fields.
5% avermectin aqueous agent 3000 times liquid: the fast-acting type is good, but it cannot kill eggs, the duration of action is short, and the use of more will cause strong resistance, which is harmful to bees.
Ethyl spiranteroid: Long-lasting and effective control for up to 8 weeks.
Biphenylhydrazine ester suspension 2000 times: effective against mites in all stages of life, fast-acting type, with egg killing and knockdown activity against adult mites, effective for about 14 days, low risk of predatory mites.
Butfluoromosteride: As a novel acetacetonitrile acaricide, relevant reports indicate that although its inhibition effect on the hatching of red spider eggs is weak, it has a high activity in all growth stages, especially for juvenile mites, with a safety interval of about 7 days.
Mineral emulsion: 7 to 14 days after medication to reach the peak of the anti-effect, but the anti-efficacy is not high, no temperature sensitivity. It is harmful to the environment.
Matrine, quinoaine, etc.: If it does not contain invisible ingredients, it is usually less effective and more likely to develop resistance; the effect of such drugs is unstable.
Once you see a red spider, be sure to take medication in time!
The medicine must be "enough water, to penetrate"!
Be sure to rotate the medication, even if this one is not as effective as the other, it must be rotated!