The temperature warms up, cherry scab and brown spot perforation disease begin to appear, are you ready to prevent it?

Temperatures are lower this spring, but as summer approaches, temperatures are about to warm up, and the ensuing leaf diseases will begin to harm growers' trees, causing inevitable losses. Therefore, prevention is the mainstay, and it will be able to prevent problems before they occur.

1. Scab disease

1, Symptoms

Cherry scabs are also known as cherry scabs. It is mainly harmful to fruits, but also to branches and leaves. Infected with the initial dark brown round spots, the size of 2-3 (mm), after becoming black brown to black, slightly concave, generally do not go deep into the flesh, when the humidity is high, the disease grows black mold, the disease part often fuses, in severe cases, there are as many as dozens of fruits, connected together to form scab-like spots. The leaves are infected with polygonal gray-green spots, and the posterior diseased part is dried off or perforated.

2. Pathogenesis

Pathogens mainly use hyphae to overwinter on the branches of the disease, the next year from April to May temperature is higher than 10 °C to produce conidia, the appropriate temperature is 20 ~ 28 °C, the suitable relative humidity is more than 80%, the pathogen directly invades the fruit, after 20 ~ 70 days of incubation, the onset of the disease begins in June, and enters the peak period of illness in July to August. Spring and summer are rainy and wet and prone to disease, and the peach orchard is low-lying, the moisture is trapped, and the planting is too dense and not ventilated. Late maturing varieties tend to have more severe disease than earlier maturing varieties.

2. Brown spot perforation disease

Mainly harmful to leaves and new shoots. At the beginning of the disease, round or nearly circular spots appear on the leaves, with purple edges, slightly chapled, and the size is 1-5 (mm); in the later stages, black-brown mold grows on the spots, and the middle is dried and shed, forming perforations, and the perforation edges are neat, often causing early leaf fallout.

Pathogens mainly overwinter in mycelium on infected deciduous leaves or branches in infected tissues, or can overwinter ascosac shells, and produce ascospores or conidia in the following spring, which are spread by wind and rain and air. The onset of the disease began in June and entered the peak of the disease in August and September. It is very susceptible to disease when the tree is weak, warm and moist.

3. Brown spot disease

Mainly harmful to blades. The leaves initially develop purplish-brown nearly circular spots with a diameter of 2-5 (mm), while pink mold forms on the back of the leaf. Later, as the leaf spots gradually expand, small black particles developed in the disease, and after the fusion of several spots, the leaves died and fell off.

The pathogen mainly overwinters on the infected deciduous leaves with ascomycete shells, and produces spores for initial infection and re-infection in the following spring. The onset usually occurs in April and occurs in June.

Fourth, prevention and control methods

1. Remove diseased leaves and branches, burn them centrally, bury them deeply or ferment them

2. Spray the whole garden with the rotting spirit before germination

3. Spray with liangguoan before flowering and after flowering

4. Spray with liangguoan and Wofeng pigment during the leaf spreading period

5. Spray liang guoan every 7-10 days from young fruit to harvest

6. When it is windy and rainy and other bad weather, prevent the use of liangguoan, wofengsu and garlic oil spray in advance to supplement nutrition, repair wounds, and inhibit germs. = The temperature is lower this spring, but as summer approaches, the temperature is about to warm up, and the ensuing leaf diseases will also begin to harm the fruit trees of the growers, causing inevitable losses. Therefore, prevention is the mainstay, and it will be able to prevent problems before they occur.

6. When it is windy and rainy and other bad weather, prevent the use of liangguoan, wofengsu and garlic oil spray in advance to supplement nutrition, repair wounds, and inhibit germs.