Occurrence and control of diseases and insect pests of cherry blossoms

Cherry blossom belongs to the genus Cherry of Rosaceae. It has the delicate fragrance of plum and the beauty of peach. There are hundreds of varieties. In recent years, with the demand of landscape architecture, cherry blossoms are widely used in gardens, adding a lot of beautiful scenery to urban gardens. However, there are many diseases and insect pests in cherry blossoms, which mainly include the following:

1 Cherry blossom sky dog nest disease

The disease is that most of the short and thin branches from the injured parts are like bird's nest, on these branches can not blossom or only a few flowers, the number of leaves on the branches is large and small, the abnormal branches are increased every year, in May to June, the leaves on the damaged branches are dark brown and wither and fall off, and gray-white spores spread to the surrounding branches in the wind. The prevention and treatment method is to cut off the damaged branches, burn off the diseased branches and leaves, spray stone-sulfur mixture before germination, and spray again in April after germination, which can achieve good results. During the onset period, you can choose 50% carbendazim 20-fold solution or other fungicides such as chlorothalonil.

2 perforated brown spot of cherry blossoms

It occurs from May to June. Purple-brown dots appeared on the leaves, then gradually expanded into a circle, and the spot became a small hole after drying and shrinking. The prevention and treatment method is to remove the diseased leaves and burn them, spray 8 ∶ Bordeaux solution before germination, or spray 45% Dysenamine water agent 40 times after germination.

3 cherry blossom leaf blight

Yellow-green round spots appear on the summer leaves, then turn brown, scattered with black particles, and the diseased leaves die but do not fall off. The method of prevention and treatment is to remove and burn the diseased leaves and spray Bordeaux liquid before germination. Spray 45% Dysenamine water agent 40 times or 0.8% chlorpheniramine No. 2 20 times after sending leaves.

4 Sclerotinia sclerotiorum

The disease occurs in leaves and young fruits. First, there are amorphous brown spots on the leaves, then spread to the whole leaf surface, and produce gray powder. The young fruit became ill soon after falling flowers, with brown spots on the surface, and then gradually enlarged, while the fruit dried and shrunk, resulting in small gray-white patches on the surface. Similar to this disease is Sclerotinia sclerotiorum, which occurs only on mature fruits. The control method is to burn the diseased leaves and fruits, and spray 6 ∶ 6 Bordeaux solution before and after flowering, 45% carbendazim solution 40 times or 25% carbendazim 50 times solution or 50% carbendazim 20 times solution.

5 Cherry blossom cancer

The patient is dark brown or dark brown, sunken, often secreting resin, usually forming cancer, but some do not produce cancer because of the tree potential and the location of the disease. The prevention and treatment method is to eliminate the affected part and burn it, or to disinfect it with 0.05-0.1% mercury water and then smear lime milk; or spray 8 ∶ 8 Bordeaux solution or Baume 5 °lime sulfur mixture before germination; or spray 500 times methyl topiramate or 50% carbendazim 20 times solution.

6 Spodoptera litura

The young moth eats the inside of the dry skin of cherry blossoms and peach blossoms, the adult body is blue-black, the 4th and 5th links of the abdomen are black, and the outer edge of the forewing is black. It occurs once a year, and the larvae spend the winter under the skin, which can be harmed in the early spring of the following year and Eclosion from August to September. The egg is laid in the space between the bark or in the wound of the dry bark. The prevention and treatment method is to apply lime coating on the branches to prevent spawning; when you see holes in the dry branches flowing glue or insect dung in the spring, you can beat the larvae with the head to kill the internal larvae or cut the dry skin with a knife to kill the larvae and remove tar from the wound.

7 plum caterpillar

It happens once a year, overwinters with eggs, hatches in March, larvae spin silk like a curtain, live in groups in the silk nest, come out at night to harm buds and leaves, and then leave the nest to disperse their activities when they grow up. Cocoon pupation was made around May, and Eclosion and spawning occurred from late May to mid June. The method of prevention and treatment is to collect egg blocks in winter or burn the nest together during the larval colony period. Adults are treated with 1000 times nicotine or other contact insecticides and stomach poisons.

8 scale insects

In addition to cherry blossoms, it also harms pears, apples, apricots, plums and other trees. The female scale shell is round, slightly raised on the back, white or even grayish white in diameter, about 0.2mm in diameter, and the male scale shell is also white, long, about 0.1cm. The prevention and treatment is to spray mechanical oil emulsion in winter or lime-sulfur mixture before sprouting in spring. The adult stage was controlled by killing scale at a rate of 2000 times.

9 other

In late April, beetles, golden flower insects, mulberry thorn inchworms can be killed, or 1000 times nicotine or other contact agents and stomach poisons can be sprayed for control. The Mongolian gray weevil was captured and killed in early May. Spray 200x Bt emulsion on the small gray weevil in early June, and spray 10% imidacloprid 2000-3000 times or other internal insecticides on aphids in the middle of June. In the middle of July, 2000 / 2000 times of chlorpromazine or 1500 / 2000 times of white red mites can be used to control red spiders. In the first ten days of August, the diamondback moth was sprayed with 1000 times nicotinine or 200 times Bt emulsion or other pesticides.