Prevention and control of perforation disease in peach trees with long brown spots and dry shedding perforation

Peach perforation disease, common fungal mildew spot perforation, bacterial perforation, brown spot perforation. There is a trend of aggravating development in recent years, and bacterial perforation is the most serious. The perforation disease of peach trees caused a large number of fallen leaves, serious shoot death, reduced yield and affected flower bud formation.

Peach tree piercing disease

(1) symptoms of harm:

1. Bacterial perforation. It is mainly harmful to the leaves, but also to the peach fruits and shoots, and the leaves suffer, at first, it is a small disease spot with water stains, and then it develops into a dark brown, and there are disease spots with yellowish halo circles around them, and cracks occur at the edges. After the disease spots fall off, they form perforations or part of them are connected to the leaves, and the disease spots are about 2 mm. The fruit is damaged, the spot is dark brown, slightly sunken, and the margin is watery. When it is wet, bacterial pus occurs in the plaque; when it is dry, cracks occur. There are two kinds of disease spots on the branches in spring and summer, and the ulcers in spring occurred on the branches in the summer of last year. After the bacteria invaded, dark brown herpes was formed on the branches in the coming spring, and withered branches were caused after expansion. Summer ulcers often occur on the new shoots of the same year at the end of summer, with lenticels as the center to form dark purple spots, slightly sunken after expansion, the color becomes darker, and the outer edge is watery.

2. Brown spot perforation. To harm leaves, shoots and fruits. Leaf damage, both sides produce round or irregular disease spot, the edge has wheel pattern, the periphery is purple, the disease spot on the later stage produces gray brown mold layer, the diameter of disease spot is 1-4 mm. The central part of the lesion dried up and fell off to form a perforation. New shoots and fruits were damaged, disease spots were similar to leaves, and grayish-brown mildew layer was also produced.

Second, prevention and control methods:

1. Apply more organic fertilizer to strengthen the tree potential and improve the disease resistance. For clayey soil, more horse dung or other organic fertilizer should be applied to improve the soil.

2. Reasonable pruning to make peach trees well ventilated and transparent; at the same time, withered branches, diseased leaves and fallen fruits should be thoroughly removed and burned or buried deeply in order to eliminate the source of overwintering bacteria.

3. Strictly control the times and quantity of irrigation, and ventilate in time. Attention should be paid to drainage in the rainy season.

4. spray control: if the perforation disease is serious in the previous year, after the nectarine leaves are spread, spray 45% streptomycin 2500 times, or 72% agricultural streptomycin 2500 times, or streptomycin sulfate 3500 times or neophytomycin 3500 times, or 50% thiram 3500 times, or 65% mancozeb 500 times, or 70% mancozeb 500 times, generally every 10 days, spray once, a total of 3 times 4 times. In addition, zinc sulfate solution sprayed with 1 ∶ 4 ∶ 240 (zinc sulfate ∶ hydrated lime ∶ water) also has a good control effect on bacterial perforation, but sometimes it is easy to cause drug damage, so a small-scale test should be carried out before use.

5. no partial application of nitrogen fertilizer, increase of phosphorus and potassium fertilizer, cultivation of strong seedlings, in order to improve the disease resistance of peach trees. Appropriate amount of irrigation, rainy days or afternoon should not be watered to prevent frost injury.