How to Control Leaf Blight of Osmanthus fragrans

How to control leaf blight of sweet-scented osmanthus trees? Please introduce that leaf blight is a common disease in sweet-scented osmanthus planting and its symptom occurs at the leaf edge and tip of the leaf. At first it is a light brown spot, then it gradually expands into a large irregular plaque. If several plaques are connected, the whole leaf will dry up. The disease spot is grayish brown to reddish brown, sometimes brittle, the edge is dark, slightly raised, and there are many small black spots scattered in the later stage, and the back color of the disease spot is lighter. Route of transmission: the pathogen overwintered in diseased leaves and fallen leaves by hyphae or conidia, and the conidia were transmitted by wind and rain. The optimum temperature for the development of bacteria was about 27 ℃. Pot place humid and muggy, poor ventilation, or plant growth weakness will aggravate the disease. The disease occurred more frequently on the old leaves after winter. There are more occurrence in the lower leaves of the plant. Prevention and control methods 1. Horticulture prevention and control should strengthen cultivation and management. Potted sweet-scented osmanthus should avoid stagnant water and increase the application of humus fertilizer and potash fertilizer to improve disease resistance. Diseased plants should be removed in time, and diseased leaves should be removed in winter to feed the source of infection. 2. During the period of chemical prevention and treatment, the Bordeaux liquid of 100 times lime can be sprayed at the initial stage, and then 50% benzoate wettable powder 1000-1500 times or 50% carbendazim 1000-1000 times can be sprayed for prevention and treatment. Click to get more sweet-scented osmanthus planting techniques