据测定每收获4,000斤甜菜块根,大约需从土壤中摄取6斤磷酸。内蒙古大部分地区土壤有效磷含量在20公分耕作层内每亩不足6斤,土默川有些地方还要低些。因此,甜菜施磷效果显著。1974年五原县试验,每亩施40斤过磷酸钙,亩产甜菜6,400斤,比不施磷的每亩增产1,100斤,每斤过磷酸钙增产28 It has been determined that for every 4,000 kg beet root harvested, about 6 kg of phosphoric acid should be taken from the soil. In most parts of Inner Mongolia soil available phosphorus content in the 20 cm tillage layer less than 6 pounds per mu, Tumochuan some places even lower. Therefore, beet phosphorus effect is significant. In the experiment of Wuyuan County in 1974, 40 kg of superphosphate per mu was applied, yielding 6,400 kg of beet per mu, an increase of 1,100 kg per acre than that without phosphorus, and an increase of 28 kg per acre of superphosphate