Article Sidebar
Article Details
NAJ supports free online communication and exchange of knowledge as the most effective way of ensuring that the fruits of research and development practice are made widely available. It is therefore committed to open access, which, for authors, enables the widest possible dissemination of their findings and, for readers, increases their ability to discover pertinent information. The Journal adopts and uses the CC: BY license and is open access. This license lets others distribute, remix, adapt, and build upon your work, even commercially, as long as they credit you for the original creation. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the Journal’s published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work. Copyright for articles published in this Journal is retained by the Journal.
Main Article Content
Effects of potassium (K) sources and rates on tuber yield and storage life of white yam (Dioscorea rotundata poir) grown in an ultisol of southeastern Nigeria
Abstract
The effect of potassium (K) sources at two rates on tuber yield and storage life of white yam was investigated. The four sources of potassium were; defatted palm kernel cake (DPKC), poultry manure (PM), their combination (DPKC+PM) as organic K source and combined NPK fertilizer as inorganic K source while the two rates were 37.5 and 75.0kg K tha-1 (low and high rates) based on their K content and a control (no application). These treatments were laid out in a randomized complete block design (RCBD) with four replications and the test crop was a local land race (Nwopoko). Planting was in April (on-set of rain) while harvesting was done at seven months after planting (November) in both 2010 and 2011. Healthy tubers of varying grades were selected from each treatment for storage studies over a period of six months. While in storage, the tubers were examined periodically for weight loss, rot incidence, sprout development and dormancy period. Tuber yields and storage data were subjected to analysis of variance. Two years (2010/11) mean indicated that among K source, poultry manure at high rate showed significant difference to the control and had 41.67, 20.48, 24.50 and 28.84% increases over combined NPK fertilizer at similar rate on number large (>1kg), small (<1kg), total number and total tuber weight respectively. Utilization efficiency test further buttressed the superiority of K sources at both rates over the control. Tubers from defatted palm kernel cake plots enhanced the storage life of the white yam tuber by recording the least loss in weight, rot incidence and sprout weight of 27.00, 9.40 and 4.75% respectively, and the longest dormancy period of 95.5 days. From the result, it can be concluded that K sources at high rate proved more effective than low rate. Poultry manure had significant increase over the control and combined NPK fertilizer in the tuber yield attributes. Defatted palm kernel cake enhanced the storage life of the white yam tuber significantly (P=0.05).
Keywords: Root and tuber, potassium, yam and utisol
