MySheen

Occurrence and control of perforation of cherry blossom brown spot

Published: 2024-11-22 Author: mysheen
Last Updated: 2024/11/22, Symptoms: the leaves start brown, grayish brown or purplish brown dots, gradually form round spots, non-waterlogged, opaque, there is no yellowish green halo around the spot, diameter 2: 4 ┨, the lesion boundary is clear, the periphery purplish brown. In the later stage, the middle part was white or brown, with slight wheel lines, and the disease spot withered and fell off, forming irregular perforation. 2. Occurrence regularity: the pathogen overwintered on the fallen leaves and spread by wind and rain in the following spring. The disease began in June, and the peak period was from August to September. When the rainfall was large, the disease occurred and prevailed, the tree was weak and the disease was serious. 3. Prevention and control methods:

Symptoms: the leaves start brown, grayish brown or purplish brown dots, gradually form round spots, non-waterlogged, opaque, there is no yellowish green halo around the spot, diameter 2: 4 ┨, the lesion boundary is clear, the periphery purplish brown. In the later stage, the middle part was white or brown, with slight wheel lines, and the disease spot withered and fell off, forming irregular perforation.

2. Occurrence regularity: the pathogen overwintered on the fallen leaves and spread by wind and rain in the following spring. The disease began in June, and the peak period was from August to September. When the rainfall was large, the disease occurred and prevailed, the tree was weak and the disease was serious.

3. Control methods: ① combined with winter pruning, cut off diseased branches, remove dead branches and leaves, and reduce the source of infection.

② trees were protected by spraying stone sulfur mixture before sprouting in spring.

At the initial stage of the onset of ③ in June, Ruidu Manganese Zinc, Carrinone, methyl topiramate and other agents were sprayed for prevention and treatment.

Bacterial perforation disease

1. Symptoms: the disease mainly occurs on the leaves, and the shoots can also be infected. The leaves begin to appear small brown spots, and then expand into a round or polygonal spot, brown or purplish brown, with a yellowish green halo around the spot. Under moist condition, there is light yellow bacteria overflow on the back of the disease spot, and the disease spot falls off in the later stage to form perforation. The tips of the branches are black sunken and cracked after damage.

2. Occurrence regularity: the pathogen overwinters in the diseased spots and buds of branches and shoots, and it is easy to cause disease epidemic when the disease is spread continuously by wind and rain and insects in spring, or when aphids and leafhoppers are seriously damaged.

3. Prevention and control methods:

Reasonable pruning of ① can increase ventilation and light transmission, and reasonable fertilization can enhance growth potential.

② was sprayed with Bordeaux solution before spring germination to eliminate the pathogen.

In the early stage of ③, carbendazim and Keshuda were sprayed to prevent and cure the disease.

 
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