Soil hydraulic properties and maize root growth after application of poultry manure under different tillage systems in Abeokuta, southwestern Nigeria

摘要

This study was carried out in 2008 and 2009 at Abeokuta, southwestern Nigeria, to evaluate the effects of tillage and poultry manure (PM) on soil hydraulic properties and maize root growth. The experiment was a split-plot design with three replications. Tillage (zero tillage (ZT), minimum tillage (MT) and conventional tillage (CT)) was the main plot while the subplot comprised three PM treatments (0, 10 and 20Mgha(-1)). Volumetric water content (theta), infiltration characteristics and maize root mass were determined using time domain reflectometer, disc permeameter and excavation method, respectively. It was observed that infiltration rate (IR) in the manured plots was higher under MT than other tillage systems in 2008 while in the unmanured plots IR was lower by 5% under ZT compared with CT. However, in 2009, IR of unmanured plots was lower under CT compared with MT and ZT by 55% and 45%, respectively. Application of PM20, which resulted in higher IR than the control under all tillage systems in 2008, decreased IR by 34% and 46% under ZT and MT, respectively, in 2009. Generally, maize root mass was lower under ZT than MT and CT; however, where PM20 was applied, root masses were statistically similar under the three tillage treatments.