玉米精播长效化肥侧位深施机的研制１９９２年北京市平原区节水型农业示范研究土壤资源良性循环课题引进７０多ｔ东北长效碳铵在京郊通县、大兴、昌平进行夏玉米生产试验。做底肥一次深施与普通碳铵等量迫施进行对比，平均每亩增产６０～９０ｋｇ，增产率１０％以上、１９９２? Research on the application of long-acting fertilizers on the side of corn sowing in deep lateral application 1992 1992 Beijing City, a demonstration project of water-saving agriculture A virtuous cycle of soil resources Introduction of more than 70 long-acting ammonium bicarbonate in the northeast Tongxian, Daxing, Changping summer Corn production test. A base fertilizer to do deep application of ammonium bicarbonate and the average amount of compulsory comparisons, the average yield per acre 60 ~ 90kg, the rate of increase of more than 10%, 1992?