Fertilizer placement of maize. II. Root growth and water use

Abstract

Normal fertilizer placement, two placements deeper than normal, a broadcast application and a non-fertilized control were compared to maximize production in a stubble tillage system. Root growth was evaluated at three growth stages from tassel initiation to flowering during the 1986/87 and 1987/88 growing seasons. Fertilizer placed in the soil stimulated deeper rooting, particularly during early vegetative growth stages. The lowest total root length was measured in no-fertilizer and broadcast treatments. No differences in total evapotranspiration were associated with treatments. The percentage of available water in the top 0.3 m soil was less than, 25% for most of the active growing period while in the 0.3–0.6-m soil layer available water generally exceeded 25%. This lead to the conclusion that fertilizer placed in the deeper soil layer is accessible to the plants for a longer period.