Response of leaf nutrient content, growth and corm yield of cocoyam (<i>Xanthosoma sagittifolium</i> Schott) to tillage and poultry manure

Abstract

In order to provide information on soil management requirement of cocoyam, three field experiments were carried out at two locations in 2007, 2008 and 2009 on an Alfisol at Owo southwest Nigeria to evaluate the effects of different tillage methods and poultry manure levels on leaf nutrient content, growth and corm yield of cocoyam. The treatments were five tillage methods: manual clearing (MC), manual ridging (MR), manual mounding (MM), ploughing plus harrowing (P+H) and ploughing plus harrowing twice (P+2H) and five poultry manure (PM) levels: 0.0, 2.5, 5.0, 7.5 and 10.0 t/ha). These were factorially combined and arranged in a randomized complete block design and replicated three times. In 2008, P+H had highest leaf N, P, K Ca and Mg, but in 2009, MC had the highest while P+2H had the least. In the first 2 years (2007 & 2008), MR, MM and P+H increased cocoyam growth and corm yield compared with MC, but in 2009, MC had highest growth and yield of cocoyam and P+2H had the least. Irrespective of tillage method, leaf K, Ca, Mg, plant height, leaf area and corm yield of cocoyam only increased up to 7.5 t/ha PM, although leaf N and P increased up to 10.0 t/ha PM. The mean data for the 3 years showed that P+H+7.5PM had highest corm yield (10.2 t/ha) while unmanured P+2H had the least (6.1 t/ha). Relative to P+2H, the P+H+7.5PM increased corm yield by 69%. In order to maximise performance of cocoyam, a combination of P+H+7.5 t/ha PM is recommended

Keywords: Tillage, poultry manure, leaf nutrient content, cocoyam, corm