There are two main types of perforation diseases on peach trees, one is bacterial perforation disease and the other is fungal perforation disease. Among them, fungal perforation disease includes brown spot perforation disease and mold spot perforation disease. In the Peach Tree Production Area of Yuncheng, bacterial perforation disease is more common, while brown spot perforation disease and mold perforation disease have occurred over the years, but the degree of impact is small, so that everyone has insufficient understanding of these two diseases.
This year, completely unexpectedly, the brown spot perforation disease is more violent in the Peach Tree production area of Yuncheng, and the typical manifestation is to cause a large number of early leaves. Because everyone does not pay attention to the disease, there are many misconceptions that there are many drug and fertilizer damages, resulting in many unnecessary disputes. There is a peach orchard, brown spot perforation disease caused a large number of leaves, the owner not only believes that it is a medicinal harm, but also does not understand the need for fungicides for peach trees. He said: "Peach trees also use fungicides?" I've never given peach trees a fungicide." This shows that it is very necessary to popularize the knowledge of diseases such as brown spot perforation disease.
A large area of fallen leaves in a peach orchard▲
The picture above shows a large number of fallen leaves and partial drying of leaves that suddenly appear after a peach orchard is watered. After on-site diagnosis, the conclusion is that the brown spot perforation disease has a serious outbreak and mixed leaf physiological dehydration.
Peach brown spot perforation disease is the initial symptom of leaf damage▲
Peach brown spot perforation disease occurs in many places on the leaves
The above two pictures are typical manifestations of peach brown spot perforation disease on leaves. The lesions are round or nearly round, with purple edges, and the junction of disease and health has a "water-stained" feature.
Symptoms at different stages of onset can be seen on one leaf
From the above figure, careful identification of this leaf, you can see that many punctate disease sites that have begun to lose green can also be seen that some spots have appeared purple-red in the middle, and you can also see that some spots have dried up, that is, the separation of diseases. The symptoms of this leaf indicate that the peach brown spot perforation disease is in the process of continuous infection in this peach orchard.
Large areas of physiological dehydration dry spots appear on the leaves
In addition to many brown spot perforation disease spots on the leaves above, there are also large areas of dry spots in the middle of the leaves, and no disease symptoms can be seen on the dry spots. How does this dry spot form? Peach brown spot perforation disease itself can lead to a large number of early leaves, the premise of early leaf fall is that the petiole produces a layer, there is a layer, the water supply is bound to be insufficient. In this case, the peach orchard was suddenly flooded with water, resulting in a lack of oxygen in the root system, difficulty in water absorption, and aggravated the lack of water in the leaves, thus leading to physiological dehydration and drying.
In terms of the degree of damage to the peach tree, although the peach brown spot perforation disease spots are small, the harm will be great. Because the rapid expansion is the culprit of early leaf fall, it is much more terrifying than the dry spots that are physiologically dehydrated.
Peach tree brown spot perforation disease, in recent years in yuncheng peach tree production area, there is an increasingly serious development trend, it is very likely to rise from a secondary disease to the main disease, must be paid great attention to.
Expert advice
The upper and lower limit temperatures for the development of the disease are 7 °C and 37 °C, and the suitable temperature is 25 to 28 °C. Therefore, when taking drugs after flowering, we must list the disease as the main prevention and treatment object. Agents can be selected from zinc manganese, methylthiocycline, diethyl methylcyclazole, isobacterium urea, pyrazole ether ester and daisen lian.
Author Li Xin talks about agriculture Li Xin teacher