The prevention and control of red spiders on citrus has always been the most headache for fruit farmers, with great harm and strong resistance, focusing on "more and more difficult to fight, more and more serious". In order to kill red spiders, various acaricides take turns, and the number of annual medications in orchards is as high as 15-20 times, and the long-term use of these chemical pesticides to control red spiders has caused serious resistance.
At the same time, pesticides such as citrus pesticide residues are serious under abuse, and pesticides such as toxic ticks, thiazides, gram mites, phosphorus killing, trizophosphate, and spironite esters have a high detection rate of pesticide residues, which directly affect the quality and safety of citrus. In order to ensure the quality of citrus and the safety of medication, the technology of using natural predators in nature to control red spiders has been vigorously promoted.
Predator mites are the star products of international pest mite control, which has been listed by the Ministry of Agriculture of China as the main technology of green prevention and control, and the subsidy for natural enemy products is as high as 90%. "Treating mites with mites" helps to reduce the use of chemical pesticides and ensure the quality of agricultural products, and has been promoted to more than 4 million mu in more than 500 counties and cities in 20 provinces in China.
However, "treating mites with mites" is easier said than done! The use of predatory mites to control pest mites is a biological control technology with very strict technical requirements, and not all orchards are applicable, and the measures are not in place or the ecological environment of the orchards is poor, and it is possible to wipe out the whole army.
Mites are used to treat mites, and mites are preyed upon red spiders
For example, a predatory mite can only prey on about 10 red spiders a day, which is ineffective during the red spider outbreak period and is released in the "window of opportunity" before the red spider outbreak;
In addition, the orchard does not produce grass or use herbicides, and the predator mites have no habitat, breeding, summer and wintering places;
Moreover, the "fragmentation" uses predatory mites, causing pests in the spraying area to run to the biocontrol area, and the effect will be greatly reduced;
Finally, the predator mites eat only red spiders and are powerless against other pests, while giving medicine and killing predatory mites. For other diseases and insects, mineral oil and plant-derived pesticides that are safe for natural enemies should be selected to control them.
Taking citrus as an example, the release of predatory mites to control red spiders requires that the main diseases and insect pests in the park are not more than 5 species, and the red spiders do not have an explosive trend, biodiversity is rich, and the pest control ability of predatory mites can be brought into play; orange orchards do not have grass or use herbicides to destroy the habitat, breeding, summer and wintering sites of predatory mites, and the prevention effect after releasing predator mites is very poor.
Safety of pesticides against predatory mites: plant-derived pesticides> fungicides> acaricides> organophosphorus pesticides
Before releasing predatory mites, it is necessary to clear the garden, release in the "window of opportunity" before the outbreak of red spiders, and use them on a continuous scale, otherwise the pests in the adjacent drug areas will run to the biocontrol area, and the effect will be greatly reduced; during the release of predatory mites, less or no drugs should be used, and "zero toxicity" biopesticides should be given priority. Because predator mites are powerless against other pests, they still have to choose mineral oil and plant-derived pesticides that are safe for natural enemies to control other diseases and insects.
Stubborn and difficult red spider
It is also necessary to move from single prevention and control to integrated prevention and control
Therefore, relying only on predatory mites, or using a single mite killer that kills mites without killing eggs, and killing eggs without killing mites, cannot prevent red spiders at all. In order to control mites and delay pest resistance, it is necessary to focus on prevention, from single medication to comprehensive control, and different agents are rotated and compounded to kill insect eggs.
Killing mites does not kill eggs, killing eggs does not kill mites, don't be stupid and confused
Still taking citrus as an example, the integrated control technology of red spiders:
1. Agricultural measures: completely clear the garden in winter, reduce the source of insects, and spray stone sulfur compounds, mineral oil, alkyne mites and other agents to remove various diseases and insect pests after fruit picking.
2, the release of predatory mites: spring or autumn, the density of pest mites is less than 2 heads / leaves (the initial stage), the temperature is released at 15-30 ° C is appropriate, half a month before and after the release of insecticidal mites and other chemical pesticides, otherwise kill the natural enemy, the red spider will soon erupt. In order to take into account the control of other diseases and insect pests, we selectively use mineral sources, plant-derived pesticides, or physical prevention and control such as yellow plates and insecticidal lamps that are effective and safe for natural enemies.
3, with the use of biological pesticides prevention: heavy "prevention" light "treatment", in the early stage of mites, population density, the number of small use of biological pesticides control, before the outbreak, it is snuffed out in the bud, prevention before the occurrence. This period is a critical period for the use of biopesticides to control red spiders.
0.5% Quinoa alkali plant source pesticide, effectively control the activity of red spiders
Plant-derived pesticides 0.5% resveratine can be used, plant essential oils and other biological pesticides, which can dissolve the waxy layer of the insect body surface dehydrated and dried to death, and is safe and harmless to predatory mites. Organisms and predatory mites jointly kill mites, so as to achieve the effect of doubling the results with half the effort, and can also reduce the cost and frequency of late medication, reduce pesticide residues, and ensure the quality and safety of fruits.
4. During the outbreak period, chemical prevention and control should be used. First, the insect mouth base is suppressed with low toxicity and high efficiency chemical preparations to achieve the purpose of controlling the continued growth of mites, and then with "biological pesticides + chemical pesticides" as a prescription list for high-resistance red spiders, insects and eggs are killed for continuous control.