玉米上有两种黑粉病:一种叫玉米黑粉病或瘤黑粉病;另一种叫玉米丝黑穗病。由于它们最后都形成大包黑粉,一般就统称这两种病为黑粉病,东北群众都管它叫“乌米”。这两种黑粉病发生十分普遍,几乎每块玉米地里都能找到。但玉米瘤黑粉病一般多发生于茎秆上,特别在接近基部的节上。据过去的研究认为,它属气流传播、局部侵染的病害。在一般情况下,受病株仍能结实,对生产的影响不很大,暂时也没有切实有效的防治方法,只要在未形成黑粉前,尽早把瘤切除就行了。而对生产真正危害较大的主要是玉米丝黑穗病,只发生在雌雄穗上(在极个别情况下,于主脉和叶缘 There are two kinds of powdery mildew on corn: one is called corn powdery mildew or tumor powdery mildew; the other is cornmeal smut. As they all eventually form large packages of black powder, they are generally referred to as smut, while the northeastern masses all call it “wu meters.” The occurrence of these two kinds of smut is very common, almost every piece of corn can be found. However, maize smut usually occurs mostly on stalks, especially near the basal nodes. According to past studies, it is a disease of airborne and localized infection. Under normal circumstances, the affected plant can still be strong, the impact on the production is not large, there is no effective and effective prevention and treatment methods, as long as the black powder is not formed, as soon as possible to remove the tumor on the line. And the real harm to the production of corn head smut is mainly occurred in the male and female ear (in very few cases, in the main vein and leaf margin