Control techniques of flower aphids, red spiders, shell insects, blight, rust and powdery mildew

The temperature is warm and cold again in spring, and the air humidity is high. At present, the occurrence of crop diseases and insect pests is moderately heavy, and there are also many diseases and insect pests in flowers. Generally speaking, there are the following serious hazards from April to May:

1. Blight

When the temperature reaches 20 ℃, newly sown flowers, saplings and some flowers with rotten roots are very prone to bacterial blight when the soil moisture is high. Prevention and control methods: 1. Before sowing, 70% pentachloronitrobenzene 1.5 kilograms of pentachloronitrobenzene was evenly mixed in the soil. 2. Control watering at the seedling stage so as not to make the soil too wet. 3, at the beginning of the disease, irrigate 1% of ferrous sulfate or 200 of 400 times 50% of Dysenammonium solution, and irrigate 2 kilograms of liquids per square meter.

2. Rust

Rose rust infects roses when they are in bud. Prevention and control techniques: 1. When the rose sprouts, the first yellow bud should be removed and burned in time to eliminate the source of infectious disease. 2. Spray 15% triadimefon 700Mel 1000 times solution in the initial invasion period.

3. Powdery mildew

Rose powdery mildew and impatiens powdery mildew mostly occur from May to June, which are easy to cause yellow leaves, withered leaves, tender shoot bending and other symptoms in summer. Prevention and control methods: 1. Pay attention to the ventilation and light transmission of flowers. 2. Apply less nitrogen fertilizer and more phosphorus and potassium fertilizer. 3. Spray 15% strychnine at the first dyeing stage with 700Mel 1000 times solution.

4. Aphids

Hibiscus, green peach, mulberry, rose, honeysuckle and so on are vulnerable to aphids. With the rise of temperature, aphids are also increasing. Prevention and control methods: 1. 40% omethoate or more or 50% imidophos is sprayed 1500 times on the water. 2. A small amount of potted flowers can also be sprayed with 100 times neutral laundry powder.

5. Red spider

The harm to jasmine, Fusang, asparagus, rose, dahlia and so on began to come out in early April. Prevention and control methods: 1, can spray speed culling 1000 times liquid. 2. A small amount of potted flowers often rinse the front and back of the leaves with tap water, or spray or dip in the 100m / 150x batter water that has been boiled and cooled, and rinse again with clean water in a day or two, which can achieve obvious results.

6. Scale insects (flower lice)

Most of the scale insects on Magnolia, rose, yellow poplar and Haitong began to hatch from mid-April to mid-May. Prevention and control methods: 1. Brush off the insect body manually before hatching. 2. Spray 40% omethoate 1000ml 1500 times during the larval incubation period.