Maize yields benefit from injected manure positioned in bands

Abstract

The use of positioned mineral fertilizer phosphorus (P) starters reduces the risk of yield penalties in maize production. However, it also increases the soil P surplus and attendant risk of P losses to the environment, in particular on farms with ample supplies of livestock manures. We examined whether routine applications of starter P can be refrained from if manure is injected in subsurface bands close to the anticipated position of the maize rows as an alternative to the conventional even injection at random lateral positions relative to the rows.Fourteen field experiments were executed on sandy soils in The Netherlands. In these experiments comparisons were made of the nitrogen (N) and P-concentrations in shoots and of dry matter (DM), N and P-yields over time, between evenly injected liquid manure (with and without starter P) and band-injected liquid manure.Silage yields of DM, N and P generally responded positively (P<0.05) to starter P applied at a rate of 9–31kg per hectare where manure had been applied at rates of circa 120kg N and circa 20kg P per hectare, but less so when the manure was band-injected. This positive response to P was not reflected in the concentration of P in shoots. Positioning of manure via band-injection without extra starter P resulted in silage maize dry matter yields that were similar to yields after even injection combined with a P-starter. Band-injection improved the recovery of the N and P (P<0.05) supplied by the manure and reduced the soil surpluses of N and P. Planting maize close to bands where liquid manure had been injected, thus increased silage yields and contributed to a better balance between the inputs and outputs of plant nutrients.