Growth and Yield Response of Soyabean (<i>Glycine max</i> Merr.) to Organic and Inorganic Fertilizer in Edo Rainforest of Nigeria

Abstract

In tropical and subtropical areas, the importance of organic manure and inorganic fertilizer in increasing crop production for food security cannot be overemphasized. A field study was therefore conducted at the Department of Crop Science, University of Benin Teaching and Research Farm, Benin City, Edo State during the 2012/2013 cropping seasons, to investigate the effects of poultry manure and inorganic NPK 15:15:15 fertilizer on the growth and yield of soya bean (Glycine max (L.) Merr). The experiment was laid out as a randomized complete block design (RCBD) in three replications with six treatments viz: 0, 200 kg/ha NPK 15:15:15, 10 t/ha poultry manure, 7 t/ha poultry manure + 60 kg/ha NPK 15:15:15, 5 t/ha poultry manure + 100 kg/ha NPK 15:15:15, 2.5 t/ha poultry manure + 150 kg/ha NPK 15:15:15. Parameters on vegetative and reproductive traits were taken on five randomly selected plants. Results showed that plant height, number of branches and number of leaves per plant were enhanced by organic and inorganic fertilizers. Similarly, combined application of organic and inorganic fertilizer increased the pod weight/plant compared to the sole application of organic and inorganic fertilizer. Application rate of 2.5 t/ha poultry manure + 150 kg/ha NPK 15:15:15 gave the highest grain yield of 7.367 t/ha followed by 5 t/ha poultry manure + 100 kg/ha NPK which gave (7.244 t/ha), application rate of 7 t/ha poultry manure + 60 kg/ha NPK gave (6.654 t/ha), while 10 t/ha poultry manure gave (3.889 t/ha) and this was followed by application rate of 200 kg/ha NPK 15:15:15 which gave (4.112 t/ha) and the control gave the lowest grain yield of (3.245 t/ha). The application of 2.5 t/ha poultry manure + 150 kg/ha NPK 15:15:15 is therefore suggested for the growth and yield of soyabean in Edo rainforest of Nigeria.