Influence of soil amendments on yield and yield characteristics of grain amaranth

Abstract

The problem of low yield in grain amaranth could be solved through selection of high yielding varieties and a consideration of appropriate nitrogen fertilizer source. The present study assessed the yield potentials of 5 grain amaranth accessions namely 74-43, RRC1351, RRC399, RRC8 and RRC551 as influenced by different nitrogen sources. The experiment was conducted at the National Horticultural Research Institute, Ibadan and Ladoke Akintola University of Technology, Teaching and Research Farm, Ogbomoso between August and December, 2015. Five accessions of grain amaranth were planted on the field at both locations. Randomized Complete Block Design was used to lay out the trial and assign treatments in the field; this was replicated thrice. Seven Nitrogen sources: poultry manure; cow dung; pacesetter organic fertilizer; brewery waste; providence organic fertilizer; Aleshinloye organic fertilizer and N: P: K were each applied at 120 kg N.ha-1and control imposed on the five selected accessions. Bi-weekly data collection was made on leaf area, dry matter index, inflorescence weight and length as well as grain yield and were subjected to analysis of variance. Accessions 74-43, RRC1351, RRC399, RRC8 and RRC551 in the two locations had good shoot biomass and stable grain yield above 1.00 t ha-1. Accession RRC8 had the highest fresh shoot weight both in Ibadan (74.2g) and Ogbomoso (82.0g). RRC551 needs some cultivar improvement as it recorded lowest shoot dry weight, infloresecence length and weight in both locations. Grain amaranth and the entire yield parameters were positively correlated with one another at p<0.01% probability level. The two agro-ecological zones were found suitable for high grain yield of grain amaranth. Addition of soil amendments to 120 kg N ha- 1 is recommended preferably organic fertilizer like cow dung.