为了供给政府作统一分配与合理施用化学肥料的参考,本所与华北、山东、河南等地十二个农场,在19(?)0年合作举行棉花、玉米、谷子、高粱等作物的三要素肥料试验。田间设计仍采用(3×3×2)复因子试验(1949——50年度小麦三要素肥料试验总结,登载本列第三年第二期第三十五页)。氮肥使用硫酸铵,分为每亩施用四十斤(合八斤氮素)、二十斤(合四斤氮素),与不施三种,磷肥使用过磷酸石灰,分为每 In order to provide the government with a unified reference to the rational distribution of chemical fertilizers, the two institutes cooperated with 12 farms in North China, Shandong and Henan provinces to hold three elements of crops such as cotton, corn, millet and sorghum during 19 (?) 0 years Fertilizer test. The field design is still using a (3 × 3 × 2) complex factor test (Summary of Three-Factor Wheat Fertilizer Practice, 1949-50, published in the third issue of the third phase, p. Nitrogen fertilizer using ammonium sulfate, divided into four acres per mu (eight pounds of nitrogen), twenty pounds (four pounds of nitrogen), and not three kinds of phosphate fertilizer used perphosphoric acid lime, divided into