Ask agricultural experts how to control wheat diseases and insect pests.

Wheat pest control needs to be prepared in stages-

Sowing date ——————————————————————————————————.

Wheat sowing date is the key period to control many wheat diseases and insect pests. This period can save labor, time and medicine, and can prevent and control a variety of pests and diseases, with twice the result with half the effort. The main pest control targets in wheat sowing date are underground pests such as grubs, grubs, needle worms, wheat midges, wheat sheath blight, take-all disease, virus diseases such as yellow dwarf, bush dwarf and head smut. Its control measures are: agricultural control should choose insect-resistant varieties according to the main local pests and diseases, and make a reasonable layout of varieties. Carefully prepare the soil and remove the sick and weeds in the field. Rational rotation, formula fertilization and application of decomposed farmyard manure. Cultivation measures such as timely sowing, precision sowing and semi-precision sowing are adopted to improve the resistance of wheat to diseases and insect pests, and to create a field ecological environment that is not conducive to the occurrence and harm of diseases and insect pests, but is conducive to the healthy growth of wheat.

Chemical control

1. Soil treatment. In the area where underground pests and wheat midges occur again, 0.25 ~ 0.3 kg of 50% phoxim or 40% methyl isocarbophos EC can be used per mu, and 25 kg of fine soil can be mixed with water 1 ~ 2 kg to make toxic soil. You can also use 2.5 ~ 3kg of 3% methyl isofenphos or phoxim granules per mu, mix them with15 ~ 20kg of fine soil, spread them evenly on the ground before ploughing, and turn them into the soil with ploughing.

2. Seed dressing with chemicals. For areas where underground pests are common, 50 grams of 40% methyl isofenphos or 50% phoxim EC can be used, 4 ~ 5 kilograms of water can be added, and 40 ~ 50 kilograms of wheat seeds can be mixed. Wheat sheath blight, head smut and stripe rust can be treated with 2% Likexiu 0. 1% ~ 0. 15% according to grain weight, or 20% triadimefon EC 0. 15% according to grain weight, or 12.5% with alkene. Excessive use of triadimefon and cereal has an effect on the emergence and growth of wheat, so the dosage should be strictly controlled to avoid phytotoxicity. Wheat take-all disease can be treated with 100 ml 2.5% suitable period, 1.5 ~ 2 kg water, 50 ~ 100 kg mixed wheat seeds, dried and sowed. 75% phorate EC100 ~150ml, 3 ~ 4 portions of water and 50kg of wheat seeds were used for wheat yellow dwarf disease and clump dwarf disease, mixed evenly, and stewed12h. In areas where pests and diseases are mixed, it is necessary to vigorously promote mixed seed dressing with fungicides and pesticides, mix pesticides first and then fungicides, and operate in strict accordance with seed dressing operation procedures to prevent human and animal poisoning.

3. Seed coating. Seed coating agent is a new type of pesticide which is compounded by pesticide, bactericide, micro-fertilizer, plant growth regulator and film-forming agent. Seed coating agent has the advantages of simplicity, slow release and long effect, which not only controls pests and diseases, but also has the function of seed fertilizer, so it should be popularized in a large area. According to the types of diseases and insect pests, all localities can choose the appropriate formula of seed coating agent. If 2.5% seed coating agent and 40% methyl isofenphos are used, not only underground pests can be controlled, but also wheat sheath blight and root rot can be controlled.

In addition, attention should be paid to the reserved spacing when sowing wheat, which is convenient for intercropping and interplanting. Intercropping and interplanting in wheat field is a simple, scientific and practical agricultural production measure, which can improve the multiple cropping index and obtain greater comprehensive agricultural benefits. The reserved rows in wheat field is the basic premise of intercropping and interplanting, and the effect of annual planting structure adjustment depends largely on the reserved rows in wheat sowing. Therefore, when sowing wheat, it is necessary to do a good job in crop layout adjustment planning, leave enough reserved rows, actively promote efficient intercropping modes such as "92", "62", "3 1", wheat, cotton, melon, wheat, melon and vegetables, and rationally configure the intercropping structure to realize 3-4 crops a year. Or when sowing wheat, the intercropping crops combination is not fixed, and when sowing in spring and summer, it should be planted according to market demand.

Seedling stage-

The prevention and control of diseases and pests in wheat seedling stage is very important, which is directly related to the growth of wheat in the future, thus affecting the wheat harvest in the coming year. Wheat seedling diseases mainly include wheat rust, sheath blight and take-all disease. Pests include underground pests and aphids. Its prevention and control methods are as follows.

Under normal circumstances, the wheat seedlings will basically grow together about 15 days after sowing, so how to manage and protect the wheat seedlings in the future is very important. The author recommends several methods to control diseases and insect pests in wheat seedling stage.

Wheat rust 15~20 days after the emergence of wheat, the wheat fields with disease were selected for investigation. When the diseased leaf rate reaches 10%, and the autumn temperature is high and there is a lot of rain, herbicide or triadimefon should be sprayed immediately for control, that is, 12.5% herbicide wettable powder 15 ~ 20g or 660 per mu.

Wheat sheath blight can occur from seedling stage to heading stage. The symptoms of seedling stage are mainly manifested in the underground part. After emergence, the underground stems of wheat were damaged, and brown spots or oval spots appeared, which developed upward. 75g of 20% triadimefon wettable powder or 40g of 20% jinggangmycin and 50kg of water can be sprayed along the ridge per mu.

The pathogen of wheat take-all disease can spread in wheat seedling stage, and the peak of spread is 20~30 days after emergence. For the plots where wheat take-all disease occurred in the past, spraying seedlings along the ridge with 12.5% Heguoli wettable powder 15 ~ 20g or 20% triadimefon emulsifiable concentrate 120 ~ 200ml and watering for 40 ~ 50kg can significantly reduce the incidence of wheat at heading stage.

Wheat aphid wheat aphid can not only directly harm and cause wheat yield reduction, but also spread wheat yellow dwarf disease. Chemical control should be carried out when the plant rate of aphids exceeds 5% and the number of aphids per hundred plants is about 10. 25 ml of aphid lice or 20 g of hero or 20 g of imidacloprid per mu and 40-50 kg of water are sprayed along the ridge, and it can also cure wheat red spider.

There are three kinds of underground pests that harm wheat at seedling stage: grubs, grubs and needle worms. It is observed that when the mole cricket is harmful, the tender stems of wheat seedlings are bitten into a ball and the fracture is irregular; When grubs do harm, bite off the roots of wheat seedlings, and the fracture is neat; Flammulina velutipes, on the other hand, got into the tender heart of the wheat straw, and the injured part was a mess, but the skin was still attached. Careful observation of these injuries of wheat seedlings can determine what kind of underground pests appear in wheat fields. 30 days after the emergence of wheat, select representative plots for investigation, and immediately carry out pesticide control when the dead seedling rate reaches 3%. Application of trichlorfon poison cake: 75g of 90% crystal trichlorfon is used per mu, which is first dissolved in warm water, and then added with water to 65,438+0.5kg to prepare a liquid medicine, which is sprayed on 65,438+00kg of crushed and fried sesame cake or rapeseed cake, and then left standing for 4-6h to obtain the poison cake. Infiltrate the poison bait into the wheat field with polonium. The effect of preventing and controlling pests and protecting seedlings by this method can reach 95%. Poison-spreading soil: 30 ~ 40 kg of fine soil per mu mixed with 2% methyl isofenphos powder, and then furrowed and applied to wheat ridges, which can effectively prevent and control the harm of white grubs and needle worms. Sprinkler solution: For the patch-damaged plots, 60 ~ 75kg of 40% methyl isofenphos or 50% phoxim water can be sprayed on the roots of wheat along the ridge per mu, which has special effects on white grubs and needle worms.

In recent years, a large number of locusts and crickets have occurred, which often harms early sowing wheat seedlings. 75g of 90% crystal trichlorfon can be used per mu. After being dissolved in hot water, water is added to 65438±0.5kg, and 5-7kg of pulverized and fried wheat bran is sprayed to make poison bait, which is spread along the ridge to trap and kill. The effect is very good.

Green jointing stage-

The key points of control at jointing stage are wheat sheath blight, midge and red spider. Sheath sheath blight is one of the main diseases in the production of high-quality wheat, which should be done sooner rather than later. Generally, pesticides are sprayed for the first time at the beginning of March and every 10 ~ 15 days. 40g of 20% Jinggangmycin wettable powder, 40g of 20% Rhizoctonia solani wettable powder, 20g of 12.5% Heguoli wettable powder or 40-50g of 20% triadimefon emulsifiable concentrate and 40-50kg of water are sprayed on the wheat base to treat wheat powdery mildew, rust and other diseases.

In recent years, the occurrence of midges is serious, generally 3-5 heads per square meter (10 cm× 20 cm), up to more than 90 heads, which leads to the reduction of wheat production or basically no harvest. In order to seize the favorable opportunity that wheat seedlings are small and easy to operate at jointing stage, when the midge larvae move up to the soil surface, the second soil treatment is carried out. An acre of 40% methyl isocarbophos EC 150 ~ 200ml or 50% phoxim EC 200ml is added with appropriate amount of water, and 25kg of fine soil is sprayed to make medicinal soil, which is evenly spread along the wheat ridge, and then the medicinal soil is turned into the soil with a shallow hoe. Alternatively, 20 kg of 3% methyl isofenphos granules mixed with 20 kg of fine soil are evenly scattered on the surface, and then the shallow hoe is turned into the soil, which can also treat pests such as the golden needle worm, white grubs and white grubs. After the investigation of some red spiders in wheat fields reached the control standard, they were sprayed with 6 ~ 8 ml of 1.8% fenpropathrin EC or 20 ml of Lvhengsha with 40 ~ 50 kg of water.

Heading, heading and flowering—

During this period, we will focus on the prevention and control of pests and diseases such as midge, red spider, powdery mildew, stripe rust and scab. Before the wheat enters the heading and flowering period (before April 25th), it is the key moment for the pulp-sucking adults to be unearthed, and 50 ml of 50% phoxim emulsion or 40 ml of 40% omethoate and 40 ~ 50 kg of water should be sprayed in time for control. When the wheat begins to blossom and the midge has already got into the wheat glume and started to suck the pulp, it is useless to spray the medicine again.

When the single row size of red spider or long-legged red spider reaches 200 or 100 respectively, spraying 6-8 ml of 1.8% chlorfenapyr emulsifiable concentrate with 40-50 kg of water per mu has obvious control effect, and can also control ear aphids.

Powdery mildew, rust and other diseases are epidemic diseases, so we must pay attention to regular investigation, and prevent them in time when they reach the control index to prevent large-scale spread. Evenly spray 20 grams of 12.5% wolliguo wettable powder or 50 kilograms of 75 ~ 15% fenxiuning wettable powder and 7 ~100g of water per mu.

If it rains for more than 2-3 days from full heading to early flowering, 50% carbendazim emulsion 100 ml or 70% thiophanate-methyl wettable powder 100 g and 50 kg of water should be sprayed immediately, which can effectively control scab.

Grouting period-

Wheat filling period is the peak period of many diseases, and it is also the key period to control pests and diseases and win high yield and high quality of wheat. The focus of prevention and control in this period is wheat aphid, powdery mildew, rust and so on. Spraying 65438+20g 00% nematode wettable powder or 40 ~ 50kg water of 25% Kuaishaling EC per mu can effectively control wheat aphids. The methods of controlling powdery mildew and rust are the same as above, and it can also treat wheat leaf blight. If the ratio of natural enemies to aphids in the field is greater than 1: 120, it is unnecessary to use pesticides to control aphids.