Effect of poultry manure and/or inorganic fertilizer on the yield of shallot [Allium cepa var. aggregatum (G. Don)]

Abstract

The study was carried out to determine the optimum levels of poultry manure, inorganic fertilizer and their combined effect on yield of shallots grown on sandy Anloga soils in Ghana. Treatments comprised a 4x3 factorial combination of poultry manure at 0, 10, 20 and 40 tons/ha and three levels of NPK 15-15-15 fertilizer at 0, 300 and 600 kg ha-1 in a randomised complete block design with four replications. A combination of 40 tons/ha of poultry manure with 300 kg/ha and 6000 kg/ha of NPK 15-15-15 fertilizer increased plant height, number of leaves per plant and number of plantlets per plant. Although application of inorganic fertilizer alone or in combination with poultry manure significantly increased bulb yield, there was a decrease in dry matter content. Sole application of 40 tons/ha gave the highest bulb yield. Our results demonstrate that farmers in the Anloga district of Ghana can rely on organic matter alone applied at 40 tons/ha for shallot production.