我县地处黑龙港下游,河北省东南部,土质有沙壤、轻壤、粘土三种,耕地面积48万多亩。除棉花外,主要油料作物是大豆和花生。其中夏大豆面积约占总耕地10%左右,推广品种是冀豆四号。当大豆长出4—5片真叶即7月中旬,发现幼苗叶片自下而上蒌蔫黄化,连片死亡,危害严重。为此,笔者进行了细微的田间调查和室内观察鉴定。一、病害发生为害情况 1987年7月中旬,在县原种场首次发现大豆孢囊线虫病(Heterodera grycines Ichins)。该场种植大豆3.3公顷,其中1公顷幼苗成片枯死。县植保站立即组织技术人员到现场观察症状及为害情况,并对全县豆田进行 My county is located in the downstream of Heilonggang, southeastern Hebei Province, soil sandy soil, light soil, clay three, arable land area of ​​480,000 mu. Apart from cotton, the main oilseeds are soybeans and peanuts. Summer soybean area which accounts for about 10% of the total cultivated land to promote varieties is Jidou IV. When the soybean grow 4-5 true leaves that is mid-July, seedling leaves were found from bottom to top 蒌 蔫 yellow, contiguous death, serious harm. To this end, I conducted a subtle field investigation and indoor observation appraisal. First, the occurrence of disease damage In mid-July 1987, the county in the original field of soybean cyst nematode disease (Heterodera grycines Ichins). The site planted 3.3 hectares of soybean, of which 1 hectare seedlings died. County plant protection station immediately organize technical staff to observe the scene symptoms and damage, and the county bean field