How to control the diseases of chrysanthemum?

How to control the diseases of chrysanthemum? Please guide gardening techniques: disease control of chrysanthemum 1. Main symptoms: it occurs on the leaves and can spread to the petiole when it is serious. In the initial stage, the disease spot is gray-black spot, surrounded by a faded green halo; after expansion, the disease spot is nearly round to irregular, the inside is grayish brown, the edge is dark brown, and there are yellow spots around it; in the later stage, the central part of the disease spot is yellowish brown and dry, and black grains appear on the disease spot in a humid environment. Second, the cause of the disease: fungal diseases. The pathogen lives in the soil and on the diseased body of the plant, and spreads with the help of wind and rain, watering, airflow, grafting and so on, and mostly infects from the stomata and wounds of plant leaves. Diseases are easy to be induced by weak plant growth, heavy soil viscosity, long-term overcast and rain, and the main factor causing serious disease is the carrying of bacteria in seedlings. Third, the control method: ⑴ changes the cultivation medium, increases the organic fertilizer, enhances the soil permeability. The ⑵ culture medium should be disinfected, and the pentachloronitrobenzene fungicide with 500x solution can be sprayed many times and used after a few days. In the early stage of ⑶, Dysen zinc or thiram fungicides were sprayed with 600x solution. Click for more chrysanthemum planting techniques click to get more flower planting techniques