用豆科作物和禾本科作物实行換茬或間套作的种植方式,提高单位面积产量和增进地力,是我国农民群众用地和养地相結合的固有經驗。近年来,我們在总結北京地区群众輪作換茬經驗的基础上,进行了有关利用春播作物前期种植“极早熟豌豆”的試驗。“极早熟豌豆”是中国农业科学院蔬菜研究所和北京市农业科学研究所試种成功的蔬菜新品种。从1962年开始,用他們供給的 It is an inherent experience of our country’s peasant masses to combine the use of land and the raising of land with the practice of cropping or grazing crops with crop rotation or intercropping to increase the yield per unit area and enhance the soil fertility. In recent years, on the basis of summing up the experience of crop rotation in Beijing, we conducted experiments on the use of early-spring planting of “very early peas”. “Very early peas ” is the Chinese Academy of Agricultural Sciences Institute of vegetables and Beijing Institute of Agricultural Sciences, a successful trial of new varieties of vegetables. From 1962 onwards, they supplied