海伦市位于松嫩平原北部,玉米种植面积较大,每年均在100万亩左右。可是由于受气候条件的影响和科学种田水平的制约,玉米单产水平较低,1985～1989年平均亩产仅为181.9公斤,低于全省平均水平的20.9%。1989～1990年我们承担了省农科院下达的在第二、三积温带玉米大面积综合高产技术开发课题,1990年9月通过专家鉴定。试验完成了以乡为单位,应用龙字号玉米品种,全乡平均公顷产5000公斤,其中亩产500公斤的地块1000亩,亩产400公斤的地 Helen City is located in the northern part of the Songnen Plain, a larger area of ​​corn planted every year in about 100 acres. However, due to the influence of climatic conditions and the restriction of scientific farming level, the yield of maize was relatively low. The average yield per mu was only 181.9 kg from 1985 to 1989, lower than the provincial average of 20.9%. From 1989 to 1990, we undertook the project of large area comprehensive high yield technology development of the second and third quarters of temperate maize issued by the Provincial Academy of Agricultural Sciences, and passed the expert appraisal in September 1990. The experiment was completed in rural units, the application of the dragon-type corn varieties, the township, an average of 5000 hectares of production, of which 500 acres of mu plot of 1,000 acres of land, 400 kg of land per mu