<p>In this paper the compaction level of a sandy-loam soil in a humid tropical climate, most suited for maize cultivation for high productivity was investigated. This involved studying the yield of maize under varying compaction conditions of the soil. Five experimental plots of land at the teaching and research farm of the Rivers State University of Science and Technology, Port Harcourt, Nigeria were used for the exercise. Four of the plots were tilled, while one was left in its original state. Three of the four tilled plots were compacted by wheel traffic; and the compaction values of all the five plots, measured by their bulk densities are 1.17g/cm<sup>3</sup>, 1.20g/cm<sup>3</sup>, 1.23g/cm<sup>3</sup>, 1.28g/cm<sup>3</sup>, and 1.35g/cm<sup>3</sup>. The plot that was left in its original untilled and un-compacted state was used as the control plot. Irrigation of the field, weed and pest controls were done uniformly for all the plots. The maize plant was cultivated between October and February and its growth and yield estimated in terms of plant height, leaf area, number of plants to reach maturity, and quantum of dry matter and grain obtained. Results of early shoot emergence showed that plots with lower bulk densities had higher percentage emergence than the ones with higher bulk densities. Furthermore, it was found that the maize yield was significantly affected by the soil bulk density at P<0.05. A compaction value of 1.31g/cm<sup>3</sup> is determined as optimal for maize cultivation in a sandy-loam soil in a humid tropical environment.</p>
Growth and yield response of streak virus resistant maize (TZESR-W) to different nitrogen rates on a sandy loam soil of semi-arid region of Nigeria
