Banded application improves the recovery of phosphorus fertiliser in a temperate pasture sward containing red clover

Abstract

Phosphorus (P) fertiliser is commonly broadcast onto existing pasture swards for ease and cost of application. However, improvements in P acquisition efficiency may be achieved by banding fertiliser. Micro-swards of red clover (<i>Trifolium pratense</i> L.) were grown in intact sandy loam soil cores with a ³³P-labelled fertiliser source. Dissolved P fertiliser was applied either to the surface or at a depth of 30 mm, to either small or large volumes of soil. Growth rates were modest and significant differences were not observed for shoot yield among treatments. However, shoot P content and P recovery were 37% and 35% higher, respectively, when P fertiliser was distributed across a larger soil volume when compared to concentrated points. Similarly, banded treatments increased recovery by 40% compared to surface-applied fertiliser. The results suggested that banded application of a low concentration liquid P fertiliser may improve the recovery of P fertiliser by pasture legumes grown in soil with a low phosphorus buffering index (PBI).