Corn response to strip-tillage and phosphorus fertilization in the Northern Great Plains

Abstract

Strip-tillage is an emerging conservation tillage/residue management system for corn production in the Northern Great Plains. Producers in Manitoba are becoming more interested in strip-tillage as it may provide many of the soil conservation benefits of no-tillage production without potential limitations of cold soils in the spring common to this region. A 2-year study evaluated corn (Zea mays L.) response to phosphorus (P) fertilization in strip-tillage and conventional tillage systems. Fertilization treatments included a control (no P), two rates of P (30 and 60 kg P2O5 ha−1), applied as monoammonium phosphate (11–52–0) either in the fall with a strip-tillage unit (as a deep-band, 10–13 cm deep) or in the spring with a corn planter (as a side-band, 5 cm beside and 2.5 cm below the seed). Spring side-banded P treatments increased early-season biomass at 2 of 4 site-years by up to 103% compared to the unfertilized controls. At the same 2 site-years, banded P treatments reduced days to silking by 2–3 days, compared to the unfertilized controls. Across all site-years, spring side-banded P treatments increased grain yield by an average of 467 kg ha−1 and decreased grain moisture content by 9 g kg−1 compared to the unfertilized control. Overall, side-banded P at planting was agronomically superior to precision fall deep-banding. There was also no agronomic penalty for corn grown with strip-tillage, compared to conventional tillage, suggesting that strip-tillage is an agronomically promising practice for corn production in southern Manitoba.