Rose powdery mildew is a common disease in greenhouses, flower gardens, flower beds and potted rose, also known as rose powdery mildew, endangering buds, leaves, and petioles of rose, rose, ten sisters, peony, yellow thorn rose, rose and other plants. Young shoots and buds. The prevention of rose powdery mildew in early spring is effective. In the early stages of leaf damage, green spots and yellow spots gradually appeared. Afterwards, a layer of white powder was formed. In severe cases, the entire leaf was covered with a layer of white powder. The leaves of the young leaves are rewinded, shrunken, thickened and sometimes purple. When petiole and young shoots become infected, the victim is slightly bulky and bends toward the opposite side. When the bud is infected, the surface is covered with white powder, malformed, abnormal flowering or unable to flower. When the damage is serious, the leaves, young shoots, and buds are covered with a layer of white powder, which causes the young leaves to shrink, and the heads to bend and wither, affecting the apical flowering and growth. The outdoor rose began to infect and develop in May. In June and July, a large number of conidia were produced on the new diseased plants and transmitted by wind and airflow. Prevention begins in the early spring and can achieve a multiplier effect. Pruning and destroying all dead and susceptible shoots in early spring can reduce the source of infection. Found that diseased, diseased leaves removed in time to destroy. During the rose cultivation in the greenhouse, ventilation is increased so that the humidity is not too high. Do not apply excessive nitrogen fertilizer and apply more phosphorus and potassium fertilizers. Spraying Bami 3 to 4 degrees lime sulfur before germination in early spring can eliminate overwintering bacteria in bud scales and effectively prevent the occurrence of rose powdery mildew; fungicides such as chlorothalonil and carbendazim are used alternately in spring growing season; Can spray 70% thiophanate-methyl 1000 to 1500 times, or 15% triadimefon 1000 times. Spray time is generally selected from 8 am to 10 am and from 4 pm to 7 pm. Indoor Ceiling Lamp,Ceiling Lamp Cover,Pure White Ultra Thin Cover,Pure White Ceiling Lamp Cover Hangzhou Lingjun Technology Co.,Ltd , https://www.lingjunelectrical.com
Prevention of rose powdery mildew in early spring