Maize cropping system analysis and economic comparison for two environments

Abstract

The effect of different maize cropping systems and economic implications were investigated at two localities from 1994 to 2000. Soil types differed, and the topsoil at Bloekomspruit and Viljoenskroon contained 17% and 5% clay, respectively. The five primary cropping systems consisted of plough × 0.92 m rows, chisel × 0.92 m rows, chisel × 1.80/0.92 m rows, rip × 1.50 m rows and rip × 2.30 m rows. Each treatment was further divided into three plant densities (15 000, 21 000 and 28 000 plants ha⁻¹). The ploughing treatment, at the highest plant density, yielded significantly higher at both localities than any of the other treatments during the wetter seasons. During average to dry seasons, however, chisel × 0.92 m rows and rip × 1.50 m rows, at intermediate and high plant densities, resulted in significantly higher yields than ploughing. Economically, chisel × 0.92 m rows and rip × 1.50 m rows were the most effective and stable treatments on the heavier soil and rip × 1.50 m rows on the sandier soil. Ploughing was shown to be a profitable economic option in some seasons but the yield variation effect over time renders it too risky a proposition. Wide row spacing was not a profitable economic option at either locality. Margins of profit for different treatments, however, depended strongly on prevailing maize prices.