Effect of rock phosphate and superphosphate fertilizer on the productivity of maize var. Bisma

Abstract

Superphosphate (SP) fertilizers have been used widely to improved food crop production in Indonesia. However, the high cost of SP is now focusing attention on rock phosphate (RP) fertilizer as a natural phosphorus (P) source and because of its relatively low cost. A field experiment was conducted to evaluate the effects of RP and SP-36 fertilizers and interaction between treatments on the productivity of maize on a Latosolic soil (low available Bray-II extractable P). A split-plot design with three blocks as replicates was used, with sources of P fertilizer as main plots and four levels of P fertilizer as subplots. Results showed that RP and SP-36 fertilizers increased maize grain yield, dry matter (DM) stover yield, and crude protein (CP) contents of maize stover over those of the control that did not receive P fertilizer. Superphosphate-36 application resulted in higher maize grain yield, DM yield, and CP contents of maize stover than crops treated with RP fertilizer at the same rate. The highest P-use efficiency for grain and stover was obtained with RP and SP-36 fertilizers that provided 66 kg P ha−1.