Response of quality, yield and growth of amaranth (Amaranthus hybridus) and soil chemical properties on application of organic and inorganic nutrients

Abstract

Poultry manure (PM) is limited by large quantity required for large scale vegetable production, to avert this problem, integrating inorganic (urea) with organic (PM) fertilizers is recently been advocated. Hence, two field experiments were carried out in years 2016 and 2017 at Landmark University, Omu-Aran, Kwara State, Nigeria to evaluate the effects of sole and integrated applications of poultry manure (PM) and urea fertilizer (UF) on soil chemical properties, growth, yield and quality of green Amaranth (Amaranthus hybridus).The study was laid out in 2 × 4 × 4 factorial experiment with two years (2016 and 2017), four levels of PM (0, 40, 80 and 120 kg N/ha) and four levels of UF (0, 40, 80 and 120 kg N/ha) application. The sixteen treatment combinations were arranged in a randomized complete block design having four replications. Results showed that UF and PM alone or their integration improved soil organic matter (OM), N, P, K, Ca, Mg (urea alone did not increase OM, P and K significantly), yield and growth indices, minerals (urea alone only increased leaf N), moisture, fibre, protein, dry matter, ash and reduced fat content of Amaranthus leaves compared with the control. Although fresh plant weight /plot (yield), plant height, leaf N and moisture contents of Amaranthus increased up to 120 kg N/ha, for both sole UF and