What are the control methods for grape sour rot?
Growing grapes is subject to many diseases, and these diseases harm grape leaves, fruit, flowers and other organs to varying degrees, having a very large impact on the growth of grape plants. Sour rot is one of them, and sour rot occurs every year in various places across our country. The affected area is not small either. It causes large-scale rotting of grape berries, affecting both yield and quality. So what are the symptoms of sour rot? How should it be controlled? Let's take a look together!
1. Disease symptoms
Sour rot mainly harms grape berries. After the berries are infected, you will find that the flesh and skin of the affected berries cannot adhere to each other. The wound also turns white, the flesh begins to rot, and liquid accompanied by a foul odor appears outside the skin, and later gradually flows out of the berry. Some red insects also appear around the berries; upon identification, these insects are vinegar flies. After the liquid flows out of the berry, the places it passes, such as leaves, flowers and shoots, all begin to rot. In the end, the entire plant dies completely.
2. Control methods
Reduce damage: This disease occurs mostly on various cracked berries and berries with wounds, so we need to reduce berry cracking. Berry cracking is most likely to occur when the soil is given a heavy watering under continuous drought weather, or when it rains. We should maintain regular watering, replenish water in time during drought weather, and pay attention to drainage when there is too much standing water. During the growing period, pay attention to applying calcium fertilizer as a top dressing, because a calcium deficiency in grapes can also cause berry cracking and similar problems.
Control diseases: A large part of the reason sour rot occurs is because of other diseases, such as anthracnose, gray mold and so on. So while controlling sour rot, we must also do a good job of preventing other diseases. The peak period for these diseases is during the grape cluster-closing and bagging stage, because no chemicals can be used after bagging, and before bagging the orchard fruit disinfection work was not done well either; the air permeability inside the bag is poor and the temperature is high, so diseases are likely to breed. Remove rotten berries, cracked berries and diseased berries promptly to reduce the spread of pathogens.
Strengthen management: Strengthening orchard management is the most basic thing. When planting, we have a bad habit, which is liking to plant different grape varieties mixed together. Actually this is wrong, because different varieties differ in their growth stages, nutritional needs and even the diseases that harm them, causing some early-maturing varieties with a high incidence of pests and diseases to pass diseases on to late-maturing varieties, and sour rot may be among them. In the process of top dressing, pay attention to the application of nitrogen fertilizer; do not apply it in a one-sided or excessive way, to prevent excessive vegetative growth. Then carry out pruning and training work in time to improve the air permeability of the orchard and prevent bacteria from breeding.
The above is a brief introduction to the symptoms and control methods of sour rot. Sour rot is a disease of secondary infection, and it is very harmful to grapes and also quite contagious. In severe cases, it may cause an entire orchard to be infected, leading to total loss of production. So everyone must do a good job of control, and reduce the incidence of various diseases, as well as some physiological phenomena such as berry cracking, in order to effectively prevent the occurrence of sour rot and improve yield and quality.