The latest course on the techniques and methods of Violet Pest Control

Violet is native to southern Europe and the Mediterranean coast. It is often introduced in big cities in southern China. In the north, it is planted in garden flower beds or greenhouses for ornamental use. It is often harmed by diseases and pests in cultivation. The main diseases are Violet Fusarium wilt, Violet Verticillium wilt, Violet white rust and Violet mosaic disease. Let's take a look!

Downy mildew

[incidence characteristics] Violet downy mildew was found in Zhongshan Park in Shanghai, which caused leaf sagging and even the whole plant to die. There are green spots on the surface of the diseased leaves, and then they turn into yellow thieves, without obvious edges, and become angled members limited by the veins of the leaves. There is a white frost layer on the back of the corresponding leaves. Tender shoots and flowers can also be infected, resulting in plant dwarfing or deformity. The pathogen overwintered with eggs in the soil and in the residual tissue of the diseased plant. The next spring began to germinate and the first infection was carried out. Too dense sowing and poor drainage are easy to cause serious disease.

[prevention and control methods] to avoid cutting Huan for too long to remove diseased plants in time, Shanghai pesticide widely trial-produced a new fungicide subpound acid ethyl A3, the concentration is 2-3 grams per liter of water.

Fusarium wilt

[characteristics] Fusarium wilt is caused by Fusarium oxysporum. The main symptoms are plant dwarfing and wilting. The young plants produced obvious veins on the leaves and caused the leaf sagging on the larger plants.

[control method] the seeds can be soaked with 50-55 ℃ warm water for 10 minutes, which can kill the germs carried by the seeds. The soil used for planting violets should be disinfected and reused. The medicament can be used with 1000 times potassium permanganate solution. If seriously infected plants are found, they should be removed and burned immediately to prevent transmission to other healthy plants.

Verticillium wilt

The symptoms were yellowing and wilting of the lower leaves of the plant. The diseased plant was seriously dwarfed and the tissue of bundle management changed color rapidly.

[control method] same as Violet Fusarium wilt.

Violet white rust

[characteristics of the disease] caused by white rust, the diseased part of the Violet plant turned yellow after infection and brown in the later stage. Chains of colorless spores are produced under the epidermis of the leaves.

[control methods] Violet white rust is also seriously harmful to other cruciferous plants. If violets are placed together with other cruciferous plants, they will infect each other, so the weeds of Cruciferae should be eradicated and isolated from other cruciferous plants. Violet plants should be sprayed with Baume 3-4 degrees stone-sulfur mixture to prevent the disease, and 65% zinc wettable powder 500-600 times should be sprayed according to the growing season. Or rust sodium 250 times 300 times the solution to control.

Mosaic disease

[characteristics] Mosaic disease is caused by Daphne genkwa mosaic virus, also known as cabbage virus 1. The virus is transmitted by 40 and 50 species of aphids, mainly peach aphids and vegetable aphids, and can also be transmitted through juices. The virus can harm many cruciferous plants and other non-cruciferous plants. Therefore, it should be isolated from these plants.

The paging symbol [control method] should be isolated from other poisonous plants, and aphids should be eliminated in time. 1.2% nicotinine 2000-4000 times or 10% imidacloprid 2000 times can be sprayed and controlled.