Pests of Dianthus and their control methods

Pests of Deutzia: Red-margined moth

symptom

The red-margined tiger moth occurs more frequently in the eastern region of my country and south of Liaoning. The adult moth hides during the day and comes out at night. It has a strong phototaxis and weak flying ability. The larvae gather in groups and cause damage after hatching, and disperse after the third instar. The larvae are relatively agile.

The larvae are polyphagous, mainly feeding on the stems, flowers and fruits of the Deutzia plant. In severe cases, the flowers and leaves of the entire plant are bitten clean, leaving only the leaf veins and pedicels.

Prevention and treatment methods

During the larval stage, you can spray with 500 times diluted Bt emulsion or 8000 times diluted 20% diflubenzuron.

After the larvae spread, they can be killed manually when they are large enough, and captured 2-3 times in a row.

When the adults are in the pupation stage, they can be killed with black light.

Pests of Deutzia odorata: White moth

symptom

The gypsy moth is a new pest discovered in coastal areas in recent years. It has a varied diet, a large reproduction rate, strong adaptability, and a wide range of transmission routes.

When the situation is serious, the entire plant of Deutzia can be eaten up by the insects, causing the death of some branches or even the entire plant.

Prevention and treatment methods

Spray 8000 times diluted chlorpyrifos No. 1 on eggs and larvae before 4th instar or adopt biological control methods such as releasing Zhou's rodent wasp for prevention and control.

Black light can be used to lure and kill adults.

Pests of Deutzia: Big Bagworm

symptom

In Henan, Jiangsu, Zhejiang, Anhui, Jiangxi, Hubei and other places, one generation occurs a year, in Nanjing and Nanchang, two generations occur very rarely, and in Guangzhou, two generations occur.

The mature larvae overwinter in sacs hanging on the branches. In Zhengzhou, the larvae resume activities in mid-to-late April of the following year, but do not feed.

The larvae are the most harmful to Deutzia odorata. They feed during the day and night and are most aggressive at night. In serious cases, you can hear the rustling sound of the larvae eating away at the leaves.

Prevention and treatment methods

During the peak period of early larvae, 800 times diluted 50% carbofuran emulsifiable concentrate can be sprayed and the adult insects can be lured and killed with black light.

Because Deutzia odorata is allergic to DDT and Omethoate, avoid using these two pesticides when insect pests occur to prevent pesticide damage.