Amornwat Srangsam and Kamnoon Kanchanapoom

pp. 697 - 702

Abstract

Field studies were made on wheat and maize crops grown on loam soil to determine the effect of
fertigated phosphorus (P) on crop yield and P use efficiency. In case of wheat, rate of P application was 33
and 44 kg P ha^-1 (not P₂O₅) from single supperphosphate (SSP) and diammonium phosphate (DAP), while to
maize it was 22 and 33 kg P ha^-1 from SSP only. The results showed that fertigated SSP enhanced the grain
yield of wheat significantly over broadcast, while fertigated DAP did not affect it significantly. Application
of lower dose (33 kg P ha^-1) from DAP by fertigation resulted in almost equivalent wheat yield with higher
dose (44 kg P ha^-1) applied by broadcast method. Phosphorus uptake, P use and agronomic efficiency were
higher in fertigation for both the P fertilizers than broadcast method. In case of the maize experiment, application of SSP by fertigation produced significantly higher grain yield as compared to the yield obtained from
same dose applied by broadcast method. The lower dose (22 kg P ha^-1) applied through fertigation resulted
in significantly higher grain yield than the full dose (44 kg P ha^-1) applied by broadcast. The P use efficiency
and agronomic efficiency were higher in fertigation than broadcast method. In both studies, fertigated P
enhanced the grain yield of the tested crops and improved the P use and agronomic efficiency, indicating
the superiority of fertigation technique.