What are the corn spider control methods? What medicine is most effective?

Corn red spider is one of the most important explosive pests in corn production. In different corn production areas, it occurs to varying degrees every year, especially after the north enters July, the continuous high temperature and drought will provide extremely favorable conditions for the occurrence of red spiders. So what are the control methods of corn red spiders? What medicine is the most effective?

Harmful symptoms of corn red spider

Corn red spider to silk drift spread with the wind damage, or crawl, or with Rain Water drift transfer damage. The adults and nymphs were clustered on the back of the corn leaves to feed on the sap, first feeding on the lower 3mur5 leaves, and then spreading to the upper leaves. The injured area showed green spots or stripes, which affected photosynthesis. After the damaged leaves lost green and dried up, they were transferred to other green leaves. Finally, the whole leaf turned rusty red and withered, showing a burning shape.

Introduction of Corn Red Spider

The scientific name of corn red spider is corn spider mite, which is mainly divided into three kinds: truncated spider mite, two-spot spider mite and cinnabar spider mite. Leaf mites occur for 10 to 15 generations a year in the north. Adult mites and nymph mites are used to suck the tissue sap of maize leaves, first harming the lower leaves, gradually transferring to the upper leaves, and then showing green spots at first, and then gradually enlarged, turning green and yellowing. When serious occurrence, the leaves completely whitened and withered, resulting in thin grain chaff and decreased grain weight, resulting in reduced yield and a serious impact on corn production.

The main reason for the formation of corn red spider

1. Temperature and humidity

From July to August, with high temperature and continuous drought and little rain, the number of insect population will increase sharply and spread rapidly from the point to the whole field.

2. Generation is short

The corn red spider has strong fecundity. 6Mel can reproduce one generation in 7 days and 20 generations a year, especially the high temperature and drought weather from July to August, which is suitable for its rapid spread.

3. Many hosts and large cardinal number

Corn red spiders not only harm corn, but also harm dozens of crops such as sorghum, brocade flowers, soybeans, cucumbers, potatoes and so on. Dozens of weeds are hosts, including ash vegetables of Chenopodiaceae, amaranth of amaranth, wild soybeans of Leguminosae, sauerkraut of Solanaceae and Bidens bipinnata of Compositae.

4. Farmers' awareness of prevention and control is not strong.

Because the corn red spider is small and the harm is hidden, the masses do not know enough about its harmfulness, and miss the best prevention and control period.

In addition, maize is a high-stem crop, and dense planting and high-yield cultivation techniques have been widely popularized in recent years, which brings great difficulties to the control work.

Prevention and cure method

1. Agricultural control removes weeds in fields, ridges and ditches, reduces food and breeding places for corn red spiders, plants resistant (tolerant) varieties, and avoids intercropping with soybeans.

2. 1.8% avermectin and 20% chlorpromazine EC were sprayed 2000 times in the field. Spray the solution on the back of corn leaves as far as possible, repeat the field, spray once every 10 days, even spray 2 times for 3 times, can achieve good results.

3. Where there are conditions for smoke prevention and control, you can choose paraben EC and avermectin EC, and use a smoke machine to prevent and cure it when the pressure is low in the morning or evening.

4. For the corn fields with high density of cutting control, cutting control can be adopted, that is, cutting 2 rows to control 12 rows, and motor spraying machine can be used for mobile spray control.

5. Fumigation in the field with 1.5 kg of 3% methamidophos granules, or 55% phosphos EC 1 kg mixed with fine sand or sawdust 20 kg, evenly sprinkled in the corn row fumigation control.

Special attention should be paid to: due to the high tightness of corn plants, hot weather, and poor ventilation conditions, it is necessary to strictly abide by the technical rules for the use of pesticides, strictly prohibit the use of highly toxic pesticides and organize mass regiments to apply pesticides. Pesticide application is strictly prohibited after 10:00 and before 5 pm to ensure the safety of human beings and animals.