Effect of Remediation on Growth Parameters, Grain and Dry Matter Yield of Soybean (Glycine max) in Crude Oil Polluted Soils in Ogoni Land, South Eastern Nigeria

The effectiveness of organic and inorganic fertilizers (cow dung, poultry manure, NPK and municipal waste compost) in the remediation of crude oil polluted soil in Ogoni, Rivers state was assessed using soybean as a test crop. A simple factorial field experiment arranged into a randomized complete block design with four replicates and twenty-four experimental plot with six treatments was used. Plot treated with poultry manure recorded the highest value of emergence (79 and 74.62%) at both seasons followed by NPK (73 and 68.32%), Cow dung (69.37 and 67.92%), municipal waste compost (66.25 and 65.3%), respectively. The least emergence (56.50 and 60%) was observed in the control for both seasons. Soybean plants height were highest in plot treated with poultry manure 4 and 6 WAP (11.48 and 12.70 cm) and (24.70 and 19.18 cm) for both seasons. There was decreased in the following order NPK (10.98 and 11.58 cm) and (23.28 and 17.05 cm), cow dung (10.18 and 11.96 cm) and (20.88 and 17.10 cm), municipal waste compost (10.03 and 11.08 cm) and (18.58 and 16.88 cm), No pollution plot (9.80 and 10.65 cm) and (16.43 and 16.70 cm) and then the control (polluted with no amendment) (8.65 and 9.33 cm) and (14.85 and 14.50 cm). NPK had the largest leaf area (12.95 and 12.70 cm2) and (14.43 and 14.56 cm2) 4 and 6WAP for both seasons, followed by poultry manure (11.80 and 11.93 cm2) and (13.72 and 12.8 cm2), municipal waste compost (12.29 and 11.53 cm2) and (12.93 and 12.49 cm2), cow dung (11.45 and 11.13 cm2) and (13.06 and 12.51 cm2), respectively. Poultry manure gave the highest grain yield per hectare (2,800 and 3,875 kg ha-1) for both seasons followed by NPK (2,220 and 2,687 kg ha-1), municipal waste compost (2,000 and 2,190 kg ha-1) and no pollution (1,575 and 1,780 kg ha-1) for both season. NPK had the highest dry matter yield at both season (8,500 and 8,000 kg ha-1), respectively. This was followed by poultry manure (7,000 and 7,500 kg ha-1), cow dung (6,000 and 7,000 kg ha-1), municipal waste compost (5,500 and 4,500 kg ha-1) and no pollution (3,000 and 2,500 kg ha-1), respectively. The least dry matter yield was observed in the control (2,500 and 2,000 kg ha-1) for both seasons. There was improvement in the dry matter yield value of poultry manure (7,500 kg ha-1) and cow dung (7,000 kg ha-1) at late planting when compared to that of early planting. Since, there were no significant differences in leaf area between NPK, poultry manure and cow dung treatments, the results indicate poultry manure as a remediation material in crude oil polluted soils planted to soybean