Which are the symptoms of sweet-scented osmanthus brown spot

The pathogen of sweet-scented osmanthus brown spot is Cercospora oleifera. It often happens in Hangzhou and other places. Sweet-scented osmanthus brown spot is a very common disease, which mainly infects leaves, seriously leads to defoliation of the whole plant, and affects flowering and ornamental. It often happens in Hangzhou and other places. Symptoms and characteristics of the injured leaves began to appear small macula, and then gradually changed into tawny to grayish brown, the disease spot is nearly round or irregular, or polygonal spots due to the limitation of leaf veins. The lesion is 2mm in diameter and has a yellow halo outside. The disease department produces black mildew spots in wet weather, which are the conidiophores and conidia of the pathogen. The pathogen of sweet-scented osmanthus brown spot overwintered on diseased plants and fallen leaves by mycelium and became the source of infection at the beginning of the next year. Conidia are produced in late March every year and begin to infect. Conidia are transmitted by airflow and raindrops and can invade directly or from wounds and natural orifices. Old leaves are more susceptible than young leaves. Brown spot occurred from April to October and subsided after November. High temperature and humidity are beneficial to the disease. There are differences in resistance among varieties. generally speaking, the disease resistance of Dangui is stronger than that of Jin Gui and Yingui. Control methods: (1) pruning in winter to remove diseased leaves and remove diseased leaves, and centralized burning; (2) at the beginning of May, spray 1 ∶ 2 ∶ 100cm 200 Bordeaux solution, and then spray 50% benzoate 1000 to 1500 times or azinamide 1000 times or 70% methyl topiramate 1000 times. Click to get more sweet-scented osmanthus planting techniques