Detailed Guide to Identifying and Controlling Common Hawthorn Diseases
The sweet-and-sour taste people talk about is probably the hawthorn. As its nutritional value has gradually become known, market demand has grown larger and larger. So more and more people have started planting it on a large scale, but many begin without any preparation at all, little knowing that they will encounter many diseases during cultivation and have no idea how to control them. So what diseases can hawthorn develop? How should they be controlled? Let's take a look together below!
1. Leaf spot disease
Disease characteristics: Leaf spot disease harms the leaves. After the leaves are infected, yellow irregular patches appear on the leaf surface, and the color gradually deepens. The patches gradually extend and expand, and finally the entire leaf turns into brown patches. Many small black dots also appear on the patches; these small black dots are the conidia of the pathogen, causing the leaves to turn yellow, wither and fall, affecting the plant's photosynthesis.
Control method: After harvesting in autumn and winter, promptly remove diseased and pest-infested branches and old branches and leaves from the orchard, burn them in a place far from the orchard to reduce the pathogens in the orchard, strengthen orchard management, apply fertilizer reasonably, and improve the tree's resistance. In the early stage of the disease, the plants can be sprayed with agents such as thiophanate-methyl for control.
2. Scab
Disease characteristics: After hawthorn is infected with scab, the disease begins on the underside of the leaves, where sparse mold spots appear. These mold spots begin to expand and finally merge in various places on the underside to form brown patches, while irregular lesions with light green also appear on the leaf surface. When it cannot be controlled, all the patches on the entire leaf merge together, and finally, just as with leaf spot disease, the whole leaf loses nutrients and falls.
Control method: Patrol the orchard regularly and carefully check the growth of each tree. If abnormal fruit trees are found, promptly remove the leaves, fruits and branches, and if any have already fallen, promptly pick them out of the orchard. To prevent the pathogen from lurking on these diseased residues over winter, in the early stage of infection, agents such as difenoconazole water-dispersible granules can be sprayed for control, once a week for one month.
3. Flower rot
Disease characteristics: Flower rot not only harms the flowers but occasionally also invades young leaves and tender shoots. When the young leaves begin to develop the disease, stripe-like patches appear on the leaves, and the infection spreads quickly, reaching about half of the plant's young leaves in about a week. The disease is even more serious after the flowers are affected, causing the flowers to rot and then fall. The incubation period for fruit infection is longer, but the symptoms are similar to those of the flowers.
Control method: As with the previous two, strengthen orchard management, do a good job of clearing the orchard in autumn and winter, and when fallen fruits and flowers are found, promptly take them out of the orchard, control the soil moisture content of the orchard, and drain excess standing water. Control the tree shape of the fruit trees to prevent injuries and wounds, and be careful with force during harvest; do not pick fruit roughly. Carry out preventive treatment on the fruit trees, spraying an appropriate amount of agents such as diethofencarb for prevention. After the disease occurs, wettable powder can be used for control.
The above are the common diseases encountered in the process of growing hawthorn. Although hawthorn has relatively strong disease resistance, if management is not up to standard, there is still a certain chance of disease occurring. Do not take chances, otherwise when disease actually appears you will be caught unprepared. Today I have only covered three; there are some others that do not occur often, so I will not go into detail. The main thing is to do a good job of orchard management, which is the best prevention method.