论文部分内容阅读
油用向日葵俗称为油葵,油葵黑斑病是向日葵的常发性病害,普遍发生于向日葵产区。一般年份造成减产10％～20％,严重者减产50％以上,如不及时预防,任由病情发展,甚至造成绝产。2000年我省武邑县66.67多公顷油葵由于发生该病颗粒无收。黑斑病已成为向日葵生产上危害严重的病害。 油葵黑斑病一般在6月份发生,到7、8月份进入盛发期。该病主要为害叶片,也可为害叶柄、茎、花、果实、花盘等各个部位。首先是下部叶片开始发病,并逐渐向上蔓延,最初叶上产生黄色小点,逐步变褐,直径1～2毫米,病斑扩大,呈圆形或近圆形;直径达5～20毫米病斑;中央灰白色,边缘褐色,如病斑进一步扩大,中央灰白部分不再扩大,褐色部分形成同心轮纹。具有同心
Oil commonly known as sunflower sunflower, sunflower black spot is a common disease of sunflowers, commonly occurs in sunflower areas. In general, it will result in a 10% to 20% reduction in production and a production reduction in excess of 50% in serious cases. If not prevented in time, the disease may be allowed to develop or even become aborted. In 2000, Wuyi County, our province more than 66.67 hectares of sunflower oil due to the disease crop failure. Black spot has become a devastating disease in sunflower production. Sunflower black spot disease usually occurs in June, to 7, August into Shengfa period. The disease is mainly affected leaves, but also damage petioles, stems, flowers, fruits, faceplates and other parts. The first is the onset of the lower leaves, and gradually spread upward, the first yellow leaves on the leaves, and gradually brown, 1 to 2 mm in diameter, lesion expansion, was round or nearly circular; diameter of 5 to 20 mm ; Central gray, brown edge, such as lesions further expanded, the central part is no longer gray-white, brown part of the formation of concentric pattern. Concentric