Sunflower Sclerotinia Control Methods

Sunflower Sclerotinia Types

Sclerotinia disease is mainly a fungal infection that causes the plant's flower disk to rot and the entire plant to wither. There are two common types:

Straight withering type

It mainly occurs in the seedling stage. Water-soaked spots appear on the stems, and white floc-like hyphae gradually grow out. When the air is dry, they turn black and the plants gradually wither and die. When the disease occurs, the stems are mainly affected, and the leaves turn yellow from the bottom to the top.

Bad disk type

This disease mainly appears after the flowers fade, with spots appearing on the flower disk and the receptacle becoming soft and brown. If it rains, the spots will gradually expand, the disease will worsen, and the entire flower disk will be covered with hyphae, causing rot.

Prevention and control measures

Physical prevention

Once disease spots are found on the stems, leaves or flower disks of the plants, the entire plant should be removed to prevent the spread of the fungus. The sclerotium has strong vitality and can survive in the soil for 3 years, so if there are other plants in the pot, it is recommended to change the soil and replant them.

Chemical control

1. Spray 1000 times of thiophanate solution before budding, spray 1 to 2 times.

2. Bud and flowering period: spray 1000 times dilution of Rhizoctonia solani solution, mainly on the lower part of the plant and the back of the disk.

3. Spray the solution of cypermethrin 500 during the seedling stage or flowering stage, once every 5 to 10 days, the preventive effect is excellent.

4. When the temperature reaches 18~20 ℃, it is the best time to spray pesticides on the ground. At this time, mixing 70% pentachloronitrobenzene with a small amount of wet soil and spreading it on the soil surface can effectively inhibit the germination of sclerotia, with a prevention effect of 80% .

Correct maintenance

Bacteria and fungi can easily grow in warm and humid environments, so it is important to control watering. For small potted varieties, try to use the immersion method to water. For home open-field cultivation, try to use drip irrigation, or use a small spray bottle for watering, which not only saves water but also prevents the occurrence of sclerotinia disease.