Identification and prevention of common diseases and pests of white radish

White radish is a common vegetable and is grown in many rural areas. To achieve high yield and high quality of white radish, it is necessary to do a good job in disease and pest control . Let’s learn about the identification and prevention of common diseases and pests of white radish.

Identification of common diseases and pests of white radish

1. Viral diseases

The leaf symptom is yellow-green leaves, sometimes with thick green lines running along the veins. The leaves are twisted, the old leaves on the periphery turn yellow, and the leaf surface becomes wrinkled.

2. Downy Mildew

It mainly harms the leaves, stems and roots of white radish. When magnified, it is a yellow-brown polygonal lesion, but downy mildew generally does not affect the heart of the leaf. When the roots are damaged, gray-yellow to gray-brown spots will form, and it is very easy to rot during storage.

3. Soft rot

The roots start mainly from the root tip and have oily brown spots. The roots then become soft and rot, and then develop new leaves, causing them to turn black and brown, become soft and rotten, and decay into a thin shape.

4. Black rot

Black rot, commonly known as black heart or rotten heart, is caused by bacteria and mainly harms leaves and roots. Black rot is a common disease of radish. The lesions spread along the veins and vascular bundles to shorten the stems and roots, and finally the entire plant leaves turn yellow and dry.

5. Brown rot

Brown rot is a common radish disease that can cause seedling death. At the seedling stage, the rhizomes of radish are damaged, small water-soaked spots begin to form, and then the lesions partially collapse, turn gray or gray-brown, and the seedlings die from the bottom to the top.

6. Diamondback moth

The diamondback moth is mainly harmful to the back of leaves, feeding on the mesophyll on the back of the leaves.

7. Cabbage aphid

The nymphs and adults of vegetable aphids are harmful to the leaves of vegetable leaves or the young leaves of seedlings, and the vegetable juice is sucked out, causing the internodes to become shorter and bent.

The control technology of white radish diseases and insect pests

1. Agricultural prevention and control

Rotate crops appropriately, including with non-cruciferous and solanaceous crops. Clear grassland weeds and pest debris, bury or burn them in a concentrated manner to reduce the occurrence of pests and diseases. Tillage should be carried out before winter to change the soil ecological conditions, deteriorate the places where pests depend on for overwintering, and reduce the sources of overwintering insects and bacteria.

2. Physical prevention

Pests such as aphids and jumpers can be captured using yellow boards, taking advantage of their coloration, phototaxis and taste characteristics. Covering with silver-gray film can be used to repel aphids. Adults such as cabbage caterpillars, armyworms and cutworms have a strong smell and can be trapped by the sweet and sour wine venom. The diamondback moth has strong phototaxis and chemotaxis and can be captured by black light, dual-wave trap light, sex attractants, etc.

3. Chemical control

Optional agents for downy mildew include imported thiophanate-methyl and metalaxyl-mancozeb. Soft rot can be treated with copper calcium sulfate, jinggangmycin, and kasugamycin. Other diseases caused by high-rot fungi, such as brown rot, black rot, leaf spot, etc., can be treated with therapeutic agents such as fenpropimorph or prochloraz. Plutella xylostella and cabbage looper can be killed by Bacillus thuringiensis and avermectin.

That’s it