Chrysanthemum planting techniques: what diseases and insect pests need to be controlled when planting chrysanthemums?

What diseases and insect pests need to be controlled in planting chrysanthemums? Please introduce the control methods of chrysanthemum diseases: the common diseases of chrysanthemum are black spot, powdery mildew and Fusarium wilt. In Shenzhen, the most serious disease of chrysanthemum is black spot. The disease occurs from the lower leaves of the plant, which appears brown spots at the beginning of the disease, then expands into round, oval or irregular disease spots, and in severe cases, the leaves turn black and die. The disease can occur in the whole growing period of chrysanthemum, especially in high temperature and rainy weather. The susceptible leaves of powdery mildew appeared yellow dots at the initial stage, and then gradually expanded and connected into pieces, and the diseased part was covered with white powdery mildew, that is, the fruiting body of the pathogen. The seriously susceptible leaves were twisted and deformed, withered and yellow fell off, and the disease occurred more frequently in spring and summer. Fusarium wilt: the above-ground leaves of the injured plant initially showed light leaf color, loss of luster, slightly wavy, wilting and drooping, slight swelling and browning at the base of the stem, rough epidermis, cracks, white mildew in the seams in severe cases, black and rotten roots, root hair shedding, harmful substances secreted by bacteria destroyed host cell tissue and blocked ducts, blocked water supply, and the plant wilted and died quickly. the disease occurred seriously in summer. The common pests of chrysanthemum are aphids and red spiders. Aphids are the main pests of chrysanthemum, the damaged part of the plant grows slowly, the leaves are curly and deformed, the seriously harmful plants yellowed and deformed, and the flower buds can not develop normally. In Shenzhen, April to May and September to October are the most harmful to autumn chrysanthemum. A large number of aphids are concentrated in the tender shoots, buds and leaf backs of chrysanthemum, causing great losses to chrysanthemum production. Red spiders often occur in the high temperature and dry season, lurking on the back of the leaves, sucking the leaf juice, making the leaves dry and yellow and withering, endangering the buds during flowering and causing the flowers to wither quickly. In order to do a good job in the integrated prevention and control of diseases and insect pests of chrysanthemum, there are three key points: first, strengthen fertilizer and water management, cultivate robust plants, and improve disease resistance. Second, prevention first, usually combined with production season and weather changes, timely use of drugs, comprehensive prevention and control. In the aspect of drug use, the mixed use of drugs can achieve better control effects, such as the mixed use of Haoshengling and Chlorothalonil, Haoshengling and Ruidui, which has a better control effect on chrysanthemum black spot and Fusarium wilt. Some insecticides can also be mixed with fungicides, which can not only achieve the effect of disease and insect control, but also save manpower. In addition, the application of carbofuran granules in the potted soil of chrysanthemum has a long-term control effect on piercing pests. Third, the early use of medicine, usually should be diligent observation. Once the signs of diseases and insect pests are found, the use of drugs for symptoms can often achieve better results, but once negligent, when the diseases and insect pests are serious, it will often get half the result with twice the effort, and greatly reduce the growth and ornamental value of chrysanthemums. Click for more chrysanthemum planting techniques click to get more flower planting techniques