黑斑病是月季花的一种严重病害。我国大部分地区发病严重，其发病率达８０％以上，病害引起大量落叶，致植株生长不良，甚至枝条枯死，降低观赏价值。此病主要为害叶片，侵染嫩枝、叶柄、花梗和花，病初叶面出现黑褐色，圆形或近圆形病斑，直径３～１２毫米，边缘呈放射状，后 Black spot is a serious disease of rose flowers. In most parts of our country, the disease is serious with the incidence of more than 80%. The disease caused a large number of deciduous leaves, causing poor growth of plants and even dead branches, reducing the ornamental value. The disease mainly leaves damage, infection of shoots, petioles, peduncles and flowers, disease early leaves appeared dark brown, round or nearly circular lesions, diameter of 3 to 12 mm, the edge was radial, after