Wheat scab often occurs in agriculture and rural areas. How harmful is scabbing? How to prevent and control farmers

Wheat will encounter many diseases in the whole growth period, such as rust, take-all disease, sheath blight, root rot, head smut, scab and so on. Among these diseases, scab is the only disease that has been highly concerned, and it is also the disease that the agricultural department emphasized to remind farmers to pay special attention to in previous years. The Ministry of Agriculture and Rural Affairs has also issued several supervision notices on scab prevention and control.

Some friends will ask, why does wheat scab cause so much concern? How harmful is scabbing? How should farmers prevent it? In this article, the assistant will talk about these issues in detail.

The Ministry of Agriculture and Rural Affairs frequently reports the prevention and control of wheat scab.

According to the contents released by official website, Ministry of Agriculture and Rural Affairs, the prevention and control of wheat scab was once again mentioned at the national on-the-spot meeting on the prevention and control of major diseases and insect pests at wheat heading stage held on April 6, 2023 at 5438+4.

April 18 released that attention should be paid to the prevention and control of scab when wheat in Jiangsu province enters the heading and flowering stage. Wheat in Jiangsu will grow earlier because of different regions and different climates.

On April 20, the prevention and control of wheat scab in Anhui Province was released, and it was predicted that the epidemic risk of wheat scab in Anhui Province was high this year. As of April 18 and 17, the whole province had controlled 3705120,000 mu of wheat scab.

On April 23, the prevention and control of scab in the main winter wheat producing areas such as Huanghuaihai was released, and the work of "one spraying and three prevention" was implemented.

In just 10 day, the Ministry of Agriculture and Rural Affairs released a number of prevention and control contents about wheat scab, which shows that the epidemic risk of wheat scab is high this year. The reason why wheat scab is special this year is mainly caused by weather factors.

From April 23rd to 24th, there was a long rainy day in central and eastern China. This is the key period of wheat heading and flowering in many places, and it is also the high incidence period of scab. With regard to the prevention and control of scab, we follow the principle of "spraying whenever we see flowers". However, when we encounter rainy weather during flowering, we can't spray drugs, and we will miss the best prevention period.

In addition, the occurrence and harm of scab will be aggravated by excessive humidity in the field when wheat is heading and flowering. On the whole, the continuous rainy weather this year not only led to excessive humidity in the field, but also failed to spray chemicals in time. Under the multiple effects, this year's wheat scab has become "special", so it is particularly important to do a good job in prevention and control in time.

Why pay attention to wheat scab?

The reason why we should pay special attention to wheat scab is because of the harm of scab, which is mainly reflected in the following three aspects.

First, the harm of wheat scab is irreversible, that is to say, once wheat is infected with scab, it cannot be cured, which will lead to reduced production or no harvest. According to statistics, the yield of wheat fields infected with scab is reduced by about 10%-20%, and it can reach about 70%-80% in severe cases, and the crops are not harvested in particularly serious plots.

For other common diseases, if they are in the early stage of onset, the harm is light, and spraying chemicals in time can promote the normal growth of wheat, and the yield will not be particularly affected.

Secondly, wheat scab will reduce the quality of wheat. According to observation, the wheat grain with scab shriveled (shriveled), and the contents of starch and protein also decreased, which led to the decrease of flour yield and wet gluten content. Compared with the wheat planted under normal conditions, the quality and nutrition have declined.

Third, wheat scab contains toxins, which will poison people and animals after eating, which is also the most important problem. Researchers found two mycotoxins in wheat infected with scab, one is monoterpene compound, and the other is gibberellin. Among them, the monoterpene compound deoxynivalenol is the most toxic, and it is also an important component causing poisoning in wheat scab.

When people and animals eat wheat with scab, they will have symptoms such as nausea, vomiting, diarrhea, general fatigue and unresponsiveness, and the symptoms will be more serious for people who are weak.

Therefore, for wheat scab, many areas also have certain requirements when purchasing. The grain content of wheat scab should not exceed 4.0%. If more than 4% of wheat scab is purchased, it needs to be properly treated on the spot and cannot be circulated in the market.

Some friends will ask, how can they tell if it is scab wheat? It's actually quite simple. The skin of scab wheat is purple, or it has pink mold. Normal wheat is yellow and easy to distinguish.

How to effectively control wheat scab?

For the wheat fields that have not yet blossomed, we should follow the preventive strategy of "spraying at the sight of flowers", and for the areas where scab has occurred, we should follow the preventive strategy of "controlling epidemic situation, ensuring yield and quality" and do a good job of "one spraying and three prevention" in time.

According to the notice issued by the National Agricultural Technology Extension Service Center, fenpropathrin, tebuconazole, prothioconazole, fluconazole, propiconazole, tebuconazole and other fungicides can be selected for control. It can be prevented and treated again at intervals of 5-7 days. If it rains within 6 hours after application, it should be sprayed again in time after the rain.