Comparison of Banded and Broadcast Fertilizer Applications in Relation to Compaction and Irrigation in Maize and Wheat

Abstract For maximum utilization of applied nutrients, the zone of nutrient concentration and root activity must synchronize. Since irrigation and compaction influence nutrient mobility and root configuration, their effect on growth and nutrient uptake were studied under different methods of fertilizer application in deep sandy loam and loamy sand soils. In studies with maize ( Zea mays L.) and wheat ( Triticum aestivum L.), fertilizer was banded or broadcast with and without irrigation and interrow compaction. Because seedling growth was faster when fertilizer was placed 20 cm below the seed, this treatment ultimately resulted in higher grain yield than when fertilizer was broadcast. In 1970, placement of fertilizer P was banded alone and increased corn yield by 40% while in 1971, placement of NPK increased maize yield by 170% over broadcast. The differences were greater with, than without, interrow compaction. Compared with broadcast, band placement of NPK increased the yield of irrigated wheat by 48% and 26% and that of unirrigated wheat by 288% and 150% with and without compaction, respectively. Treatment effects on nutrient uptake followed the same trends as those on grain yield. Fertilizer should not be broadcast where root growth in the surface layers is likely to be restricted due to surface drying or compaction. In compacted plots, heavy and infrequent irrigations appeared to be desirable because they resulted in significantly higher uptake of N. In the absence of compaction, nutrient uptake in the two irrigation practices was similar but grain yields were higher with frequent light irrigations than with infrequent heavy irrigations.