Citrus sinensis powdery mildew
Symptoms: Powdery mildew is a common disease of cineraria, and leaves, shoots, buds, buds and other parts can be infected. At the beginning of the disease, a layer of white mold layer grows on the surface of the damaged part, the edge is not obvious, and then gradually expands and becomes light gray, and produces small black dots. After the plants are damaged, the flowers are not able to open normally and the leaf curls and shrinks. Affect the ornamental value, when the leaves gradually die, or even the whole plant died. Incidence regularity: The pathogenic bacteria use mycelia to overwinter on diseased shoots, diseased leaves, and diseased branches, and infested with germination of new shoots the following year, and spread with the wind. Powdery mildew is usually severe in spring and autumn, but the annual incidence of cineraria produced in greenhouses can be affected. The occurrence of powdery mildew can be caused by insufficient sunlight, poor ventilation, and partial application of nitrogen fertilizer. Control methods: 1. Alcohol wipes: Wipe the leaves of damaged parts 3-4 times with an alcohol swab to make the powdery mildew disappear quickly, without harm to the flowering plants. 2. Leek juice spray: Wash and smash the leek to take juice, each city two leek juice add half a catty of water, spray with liquid once, after 3-4 consecutive times, the flower line is returned to normal. 3. Washing liquid detergent: Take detergent powder? Neutral is good? 2 copies, watered 1000 copies, dubbed solution rinse, wait 2-3 minutes to rinse with water, once every 2 days, continuous rinse 2-3 times Visible effect. 4. Baking soda liquid spray: Take 2 baking sodas, add 988 waters and make up a 0.2% solution. Spray this solution once every 4 to 5 days. Continuous spraying 3 to 4 times can be effective. 5. Juice spraying of walnut leaves, oleander leaves, and A. annua leaves: fresh leaves of Walnut, oleander and A. annua were taken in equal portions, followed by one serving of raw pepper, and a total of 10 times dilution of juice and water was added. ,Spray or scrub the stems and leaves with a brush, once every 3 to 5 days, 3-4 times can be effective. 6. The sick branches are cut off in time and burned down; rational fertilization is applied to increase ventilation and light transmission, and proper spacing between rows is maintained to reduce the occurrence of diseases.