Fertilizer values of composts as affected by plant materials and composting duration on maize (<i>Zea mays</i>) performance

Abstract

Chemical properties and nutrient release pattern from compost are influenced by composted plant materials (CPM) and duration of composting (DC). The following plant materials; guinea grass (GGC), tridax weed (TWC), siam weed (SWC) and maize stover (MSC) were composted with cow dung. Pot and field experiments were carried out to evaluate the effect of these CPM on growth yield performance of maize, and the properties of soil after harvest. The pot trial was a 4 × 5 factorial experiment laid out in a completely randomized design (CRD) with three replicates while the field experiment was a 4 × 3 factorial arranged in a randomized complete block design (RCBD), replicated three times. Data collected on initial and soil properties after harvest, growth, dry matter yield (DMY), nutrient uptake and yield of maize were subjected to analysis of variance and means separated using Duncan Multiple Range Test. Results showed that MSC compost had the highest N content while GGC had the highest K. Phosphorus (P) content was similar for all the CPMs. Results of pot experiment showed that maize growth was higher (p ≤ 0.05) with GGC, TWC and MSC of 3, 4 and 5 months DC. The DMY and P-uptake increased with increasing DC. On field trial, plants height was similar for all the CPM that received MSC and GGC gave similar highest DMY which were significantly higher than TWC and SWC. MSC gave the highest N-uptake while GGC treated plant had the highest P and K uptake. Grain yield was significantly higher for MSC (1.80 t ha^–1) than SWC and Control but similar to GGC (1.37 t ha^–1) and TWC (1.18 t ha^–1). Compost application at 20 t ha^–1 significantly increased cob weight, N and K uptake of maize compared to control. Application of CPM improved final soil available P which increased with DC and rate of application of different CPM. Therefore, CPM and DC have great potentials in influencing compost quality and should be considered in formulating compost fertilizer in organic farming.