Abstract

The experiment was conducted at Teaching and Research Farm of University of Port Harcourt between May and August, 2016 to determine the influence of different soil management practices on soil organisms and maize yield (Zea mays L.) in South Eastern Nigeria. The experiment consisted of six treatments, namely:  control (no application), cover crop (pumpkin cover), 10 t/ha dry guinea grass mulch (dead mulch), 10 t/ha poultry manure, 250 kg/ha N:P:K 15:15:15 and 10 t/ha dry guinea grass as bush burning material. These treatments were laid out in a Randomized Complete Block Design with four replicates. Results showed that the initial bacterial count was 2.0 × 10⁶ CFU/g, fungal count (1.7 × 10⁵ cfu/g), and earthworm casts (0). The soil was sandy loam and the pH was very strongly acid (4.80). At 11 weeks after application (WAA), NPK treated plots had the highest bacterial count (4.6 × 10⁶ CFU/g), while cover crop and dead mulch plots had the highest fungal count (1.9 × 10⁵ cfu/g). At the point of harvest, the highest earth worm casts (19.00) were in cover crop. The most predominant bacteria isolates across the various soil management practices were Bacillus and Pseudomonas species, while that of fungal were Aspergillus niger and Candida species. Maize yield differed significantly (p<0.05) among various soil management practices. In spite of the variation in the population of soil organisms, NPK plots produced the highest yield (170 kg/ha) and is therefore recommended.

Key words: Influence, maize yield, soil management practices, soil organisms, Southeastern Nigeria.