一、上壤含磷少于10ppm 的,属于极度缺磷。这样的地块,小麦亩产要达到200公斤,每亩可施磷肥(过磷酸钙)25～40公斤;如要达到400公斤,则需施磷肥40～50公斤。二、土壤含磷在10～20ppm 的,也属于缺磷。这样的地块,小麦亩产要达到200公斤,亩施磷肥要在10～15公斤;亩产达400公斤的,亩施磷肥需30～40公斤。三、土壤含磷在20～30ppm 的,属于可能缺磷,小麦亩产要达到200公斤,可暂不施磷肥;亩产要达到400公斤,则需施磷肥15～25公斤。 First, less than 10ppm of phosphorus on the soil, belonging to the extreme lack of phosphorus. Such plots, wheat mu produce 200 kilograms per acre can be applied phosphate (superphosphate) 25 to 40 kilograms; To reach 400 kilograms, you need to apply phosphate 40 to 50 kilograms. Second, the soil phosphorus in 10 ~ 20ppm, also belong to lack of phosphorus. Such plots, wheat mu to achieve 200 kilograms, Mushi phosphate fertilizer in 10 to 15 kilograms; per mu up to 400 kilograms, Mushi phosphate required 30 to 40 kilograms. Third, the soil phosphorus in the 20 ~ 30ppm, belonging to the possible lack of phosphorus, wheat mu to 200 kg, temporarily without phosphate; mu to reach 400 kg, you need to apply phosphate 15 to 25 kg.