PPI/ PPIC has studied the contribution of fertilizers in numerous provinces through maximum economic yield( MEY) research comparing traditional farming practices to an adequate and balanced fertilization approach to crop production.

• 钾磷研究所/拿大钾磷研究所(PI/pic)通过最高经济产量研究(EY)比较传统农作措施与充足平衡施肥措施，研究了在大多数省份肥料对作物生产的贡献。