What are the common diseases of rhododendron?

What are the common diseases of rhododendron? Please introduce and guide the prevention and control methods of rhododendron common diseases are as follows: rhododendron leaf spot symptoms mainly infect leaves, at the initial stage, the leaves appear reddish brown spots, gradually expand into disease spots or irregular polygonal spots, dark brown. In the later stage, the central tissue of the lesion turned gray. When the disease is serious, the disease spots are connected to each other, resulting in withered and yellow leaves and early fall. Prevention and control methods 1. The fallen leaves were removed and treated in autumn, and the diseased leaves were removed in time during the growing season. two。 The density of planting or potted flowers should be suitable to ensure that the plants are ventilated and transparent, reduce the leaf humidity, and put potted flowers in the outdoor shade shed in summer to reduce the wounds caused by sunburn and mechanical damage. 3. Immediately after flowering, 65% Dyson zinc wettable powder 500 Mel 600 times or 50% carbendazim wettable powder 500 Mel 800 times were sprayed. Spray every 10 Mel 14 days for 3 times in a row. Brown spot of rhododendron is the main disease of rhododendron. At the beginning, the leaves produced small brown spots, which fused with each other, and gradually developed into large spots, the disease spots were irregular, the positive complexion was darker and the negative complexion was lighter. In the later stage, the middle of the lesion becomes grayish brown, and a lot of black or grayish brown is produced on the spot. In severe cases, the branches are completely exposed and the plants are weak. At the initial stage of the disease, the prevention and treatment program was sprayed with 1RV 120 Bordeaux solution, or Baume 0.4 degree stone sulfur mixture, or 65% Dyson zinc wettable powder 500 times, or 25% carbendazim wettable powder 300 times, once every 10 times every 14 days, for a total of 4 times. Click to get more azaleas planting techniques click to get more flower planting techniques