EFFECTS OF ORGANIC AND INORGANIC FERTILIZERS ON SOIL CHEMICAL PROPERTIES AND THE YIELD OF Amaranthus species IN A CONTINUOUSLY CROPPED ULTISOL
Akinmutimi, A.L. and Okoroji¸ M.C.
Akinmutimi, A.L.: Department of Soil Science and Land Resources Management, College of Crop and Soil Sciences, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, Abia State, Nigeria.
Okoroji¸ M.C.: Department of Soil Science and Land Resources Management, College of Crop and Soil Sciences, Michael Okpara University of Agriculture, Umudike, P.M.B. 7267, Umuahia, Abia State, Nigeria.
ABSTRACT
Field and laboratory experiments were conducted to evaluate the effects of poultry manure and NPK (20:10:10) fertilizer on soil chemical properties and yield of Amaranthus species. The treatments were: T1-Control (no fertilizer), T2-NPK 20:10:10 (200kg/ha), T3-Poultry manure (5 tons/ha), T4-NPK 20:10:10 (100kg/ha) + Poultry manure (2.5 tons/ha), T5-NPK 20:10:10 (100kg/ha)+ Poultry manure (5 tons/ha), T6-NPK 20:10:10 (200kg/ha)+ Poultry manure (5 tons/ha. The experiments were laid out in a randomized complete block design (RCBD). The soil was strongly acidic, having a pH of 5.1 and low in % total Nitrogen (0.10), % organic carbon (1.13) and the exchangeable bases. From the study, the poultry manure 5t/ha + NPK (20:10:10) 100kg/ha gave the best yield of Amaranthus species, followed by poultry manure 5t/ha + NPK (20:10:10) 200kg/ha which gave an increase in soil chemical properties. It is recommended that the combination of poultry manure 5t/ha + NPK (20:10:10) 100kg/ha fertilizer could be used for profitable Amaranthus production in the study area.
Keywords: Organic fertilizer, Inorganic fertilizer, Soil chemical properties, Yield, Amaranthus species