Plum Blossom Leaf Curl Disease Prevention and Treatment
Plant knowledge series, sharing with you the knowledge of plum blossom clinic, the prevention and treatment of plum blossom leaf curl disease, next, let's understand together.
I. Symptoms of Harm
Mainly occurs in spring, the first to be affected are the new buds and leaves, the young shoots become thickened and shortened, the leaves are dense, the leaf surface is wrinkled and thickened, becoming succulent, rough on the surface, and curling towards the leaf back. Initially, the affected leaves are yellow, red, or purplish red, and gradually turn grayish white, with powdery substances appearing. In severe cases, the affected shoots die, the tree vigor is weakened, and the flower yield is reduced.
II. Disease Development Pattern
The ascospores and芽 spores overwinter on the affected shoots inside and outside the host bud scales. The mycelium is annual or perennial, and the芽 spores have two types of thin-walled and thick-walled, the former can continue to芽 proliferate, and the latter have dormant and resistance to adverse environmental effects, after surviving adverse conditions, they germinate to form芽 spores that infect the host. In early April of the following year, the pathogen begins to infect, and the disease is more severe in early May, and stops in June. The pathogen infects once a year, and occasionally re-infection occurs. However, due to high temperatures and unsuitable conditions, the harm is not significant. Cool and humid weather is most suitable for spore germination and infection. About 20°C is most suitable for the growth of the pathogen, and the growth of the pathogen is inhibited at 28°C, and the disease cannot occur. Early spring continuous rainy or foggy weather is not conducive to the occurrence of the disease.
III. Control Techniques
1. If pruning is necessary in winter, be sure to collect all fallen plum leaves and branches and clean the plum garden. In combination with winter pruning, when managing topdressing, apply more decomposed high-quality organic fertilizers and phosphorus-potassium fertilizers, and apply less or no nitrogen fertilizers to promote the healthy growth of plum branches and leaves and improve the plant's resistance to plum leaf curl disease.
2. If pruning is necessary in spring, take the cut-off diseased branches and leaves out of the garden and burn them together to reduce the source of pathogens for the next year. When removing diseased branches and leaves, you can soak the pruning shears in a 1:1:100 Bordeaux mixture for 3 to 5 minutes before cutting.
3. You can spray a 5-degree lime sulfur mixture or a 1:1:100 Bordeaux mixture when the plum leaf buds are just swelling. Spray 1 to 2 times a year, continuously for 2 to 3 years for better results. Note that when spraying, make sure to spray evenly to form a medicine film.
4. For potted plum blossoms, in addition to pruning branches and leaves in winter and spring and burning the diseased branches and leaves away from the pot, the environment around the pot must be kept dry, which helps to suppress the occurrence of pathogens. If plum leaf curl disease has occurred, spray each pot with the aforementioned medicine and concentration.
The above-sharing of the green plant flower knowledge and experience in preventing and treating plum leaf curl disease, hoping to bring help to you in life!