Abstract:
Soil physical and chemical properties and cassava (Manihot esculenta) performance were evaluated in an alfisol giving eight tillage cum ash treatments in Akure, southwest Nigeria in 2012 and 2013. The treatments were no till (NT), NT + wood ash application (NTA), manual slashing (MS), MS + ash (MSA), manual ridging (MR), MR +ash (MRA), heaping (HP), and HP +ash (HPA). The aim of the work was to evolve a suitable tillage combined with manuring package for cassava production. The soil test was low in organic matter (OM), Ca, Mg, acidic and bulk density. Relative to NT, MSA, MR, and HP increased number of leaves, plant girth in 2012 and 2013. Plant height increased in 2012. The MSA, MR and HP increased tuber length and number of tubers. Consistently MR gave height values of the parameters. Without ash, NT and HP had least tuber weight respectively. Addition of ash to NT and tilled soils increased cassava growth and yield significantly. The MRA had highest values of performance parameters; it increased tuber weight by 174% relative to NT. Among four tillage treatments, ridging and heaping significantly reduced soil bulk density, increased porosity and gave lower soil moisture content. Ash addition reduced soil bulk density, increased porosity, Ph, N, P, K, Ca and OM. Tillage did not influence soil chemical properties significantly although manual ridging plus ash had highest soil N and P.
