EFFECTS OF DIFFERENT SOURCES OF ANIMALS’ MANURE AND INORGANIC FERTILIZERS ON GROWTH, YIELD, AND YIELD RELATED PARAMETERS OF MAIZE (Zea mays L.) AT ALAGE, CENTRAL RIFT VALLEY OF ETHIOPIA

Abstract

Field experiment was conducted to assess the effect of sources of animals’ manure and rates of inorganic NP on yield and yield related parameters of maize on the saline soil at Alage, southern Ethiopia. Factorial combinations of three sources of animals’ manure (beef, goat, and poultry), and five rates (0, 25%, 50%, 75%, and 100%) of the recommended dose of inorganic NP fertilizers (92 kg N ha-1 and 69 kg P2O5 ha-1) were laid out in randomized complete block design with three replications. The interaction effect of sources of animal and inorganic NP were significant on soils AvK, AvP, OC, TN, CEC, Ex Ca, Ex Mg, Ex Na, ESP, and SAR. The highest available potassium (157.887 mg /kg) was obtained from use of beef manure and 100% of the recommended NP, the highest available P (15.0 ppm) was recorded with beef manure at 25% of inorganic NP, the highest organic carbon content was recorded with the application of beef manure with the zero NP, the highest total nitrogen (0.243%) was obtained from poultry’s manure at 50% inorganic NP, and the highest CEC (33.71 cmol (+)/kg) was obtained with poultry manure combined with 100% NP. Similarly, the interaction effect was significant on 10 days to silking, days to physiological maturity, number of kernels per ear, aboveground dry biomass, and harvest index. The highest days to silking (72.0 days), days to maturity (160.0 days), and number of kernels per ear (558.3) were recorded with the combination of poultry manure and 100% inorganic NP, while the highest above ground dry biomass (28.21 t ha-1) was recorded at the combination of goat’s manure at the level of 100% inorganic NP. The main effect of manure source showed significantly highest days to 50% tasseling (67.93), plant height (2.37 m), and thousand kernels weight (504 g) with the application of poultry manure. Likewise, the main effect of inorganic NP showed that as the rate of inorganic NP increased from zero to 100%, days to 50% tasseling, the plant height, ear length, number of ears per plant, thousand kernel weight and grain yield were increased significantly. Thus, the highest maize grain yield (11.832 t ha-1) was obtained with the application of 100% of inorganic NP and among the sources of manure, poultry manure gave the highest grain yield (10.594 t ha-1).