Red spiders, known scientifically as leaf mites, are a common plant pest. They mainly live by spinning silk and weaving webs on host plants, and sucking SAP with thorns. Despite its tiny size, less than 1 millimeter, starscream reproduces quickly and prefers hot, dry conditions, posing a threat to plants. This paper will introduce in detail how to identify and effectively prevent red spider from the basic information, form recognition, occurrence rule, harm and control methods.
The Basic Information Of Starscream
Red spiders, belonging to the arachnids, Acariidae, and phylloacariidae, are common pests on a variety of plants. They feed on the SAP of plants and roost on plants by spinning silk and weaving webs. There are many kinds of red spiders, such as citrus red spider (citrus panonychus mite), citrus yellow spider (citrus Eophylla mite, citrus four-spotted yellow spider), white spider (two-spotted leaf mite), etc., but their habits and harm methods are much the same.
Red spider is mainly in the form of eggs or fertilized female adult mites, overwintering in the leaves, cracks in the branches and shallow soil around the plants. When the plants begin to sprout and grow the following spring, the overwintering female adult mites become active and reproduce. Under normal circumstances, the red spider infestation reaches its peak period in mid-May, and the peak period occurs from July to August throughout the year, especially from late June to early July.
Red Spider Shape Recognition
Red spiders are tiny and usually invisible to the naked eye, but by observing their morphology and habitat, we can initially identify them.
Adult morphology:Adult mites are small, round or oval, orange or reddish-brown in color. The dorsal side usually has a small tuberous projection, and the body surface is smooth or has burrs. Adult mites have four pairs of legs and are able to move flexibly.
Egg morphology:The eggs are oblate or round, bright red or orange-yellow and shiny. The top has a vertical long or short handle, easy to identify.
Juvenile and minor mite morphology:Juvenile and juvenile mites are similar in size to adult mites, but smaller in size. Juvenile mites have 3 pairs of feet and are light in color. If the size of the mite gradually increases, close to the adult mite, but the size is still small.
Habitat:Red spiders like to perch on the back of leaves, especially near the veins. There is also a small distribution on the front of the leaves and on the stalk. They spin silk and weave webs, forming a white omentum that covers the leaves.
The Occurrence Of Red Spider Law
The occurrence of red spider is closely related to temperature, humidity, plant species and growth conditions.
Temperature:Red spiders like a high temperature and dry environment, occurring at the temperature of 12-26 ° C, and the best time is about 20 ° C. When the temperature is too high or too low, the red spider’s ability to reproduce and harm will be weakened.
Humidity:Too low humidity is conducive to the reproduction and harm of red spider. High humidity is not conducive to the survival and reproduction of starscream.
Plant species and growth status:Different plants have different resistance to red spiders, and some plants are more vulnerable to red spiders. The growth condition of the plant will also affect the occurrence and harm degree of red spider. Weak plants, for example, are more vulnerable to red spiders.
Seasonal changes:The occurrence of red spiders is closely related to seasonal changes. Generally speaking, spring and autumn are the peak of starscream occurrence. In these two seasons, plants begin to sprout and grow or fall dormant, and starscream will take advantage of this opportunity to reproduce and harm.
The Danger Of Red Spiders
The harm of red spider is mainly manifested in the following aspects:
1. Leaf chlorosis:Leaves affected by starscream will lose green, yellow, and even appear reddish-brown spots. The leaves gradually lose their luster, become rough, and fall off directly in severe cases.
2. Stunted growth:Long-term damaged seedlings tend to become weak and their resistance decreases. The plant is stunted, the growth rate slows down, or even stops growing.
3. Reduced viewing value:The leaves of plants seriously affected by red spiders will become mottled and lose their ornamental value. For flowers and ornamental plants, this will affect their market value and ornamental effect.
4. Other pests and diseases:Plants with reduced resistance are more vulnerable to other pests and diseases. This will lead to the further aggravation and spread of plant diseases.
Red Spider Prevention Methods
The control methods of red spider mainly include prevention, physical control, chemical control and biological control.
Prevention:Strengthen plant maintenance management, improve plant resistance.
1. Fertilize and water properly, avoid excessive fertilization and watering resulting in over-growth or weakness of plants.
2. Regularly remove fallen leaves and weeds around plants to reduce starscream habitat.
3. Before the starscream peak, use a preventive agent to spray.
Physical control:Remove red spiders and eggs by gently wiping the back of the leaves with your hand or a damp cloth.
Flush the back of the blades with a high-pressure water gun to wash the starscream away.
However, after washing, it is necessary to carefully check whether the leaves have egg residue, and clean up in time. Wipe the leaves with tobacco water or garlic rice water, and use the irritating smell of tobacco leaf or garlic rice to repel red spiders.
Chemical control:Spray with acaricide. The commonly used acaricides are bedeciline, avermectin and so on.
When spraying the agent, pay attention to the concentration and use of the agent. Avoid excessive use that can cause plant damage or develop resistance.
Spraying should be uniform and thoughtful, especially on the back of the leaves and hidden parts of the plant.
According to the occurrence of starscream, timely adjust the dosage and spraying frequency of the agent.
Biological control:Use natural enemies for control. The natural enemies of the red spider are the Chinese Chrysopleus, the Thaliothrips, the mite eater ladybird and so on.
Plant some natural enemies like plants around the plants to attract natural enemies to come to roost and breed.
Avoid the use of chemical agents harmful to natural enemies and protect the survival and reproduction environment of natural enemies.
Conclusion
Take the rose as an example, when the rose leaves appear pinhole-like yellow and white spots, we should be alert to the danger of red spiders. At this point, you can turn the back of the leaf to see if there are white, red or black particles and the presence of red spiders. Once you find red spiders, take immediate measures to prevent and control them.
In the prevention and treatment process, we should pay attention to the following points:
Early detection: red spider initial harm is light, easy to control. Therefore, it is necessary to check the plant leaves regularly to find and deal with red spiders in time.
Comprehensive control: adopt physical, chemical and biological methods for comprehensive control to improve the control effect.
Drug use: When using the drug, pay attention to the concentration of the drug and the method of use. Avoid excessive use that can cause plant damage or develop resistance.
Natural enemy protection: In the process of prevention and control, attention should be paid to protecting the survival and reproduction environment of natural enemies to avoid harm to natural enemies.
Through the above identification and prevention methods, we can effectively control the harm of red spider and protect the healthy growth of plants. At the same time, strengthening plant conservation management and improving plant resistance are also important measures to prevent red spider hazards.
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