Effect of different Rates of Wood Ash on Exchangeable Aluminum, Growth, Nodulation, Nitrogen Accumulation and Grain Yield of Soybean (Glycine Max (L.) Merrill) in an Acid Ultisol

Response of soybean grown on acidic soil to wood ash applied at 0, 2, 4, 6, and 8 t ha-1 was studied in two field experiments in 2003 and 2004 at Umudike in the rainforest zone of Southeast Nigeria. Treatments were fitted in a randomized complete block design (RCBD) replicated three times. Effect of treatments on some soil fertility and productivity parameters were evaluated. The wood ash contains 64.30 g kg-1 Ca, 12.20 g kg-1 Mg, 9.03 g kg-1 K, 8.75 g kg-1 P and 4.84 g kg-1 N, and had a pH of 11.07. Soil pH increased significantly from 4.80 to 6.40, while levels of exchangeable Al3+ correspondingly decreased from initial values of 2.50 cmol kg-1 to 0.21 cmol kg-1 when 4 t ha-1 of wood ash was applied. Estimation of linear and quadratic curves respectively for soil pH and exchangeable Al3+ indicated values of r2 = 0.973** for soil pH and R2 = 0.944** for exchangeable Al3+. Significant increases (P < 0.01) in soil Ca, P, K, status relate to patterns of growth, nodulation, nitrogen accumulation and grain yield of soybean. The application of 4 t ha-1 wood ash gave grain yield of 2028.34 kg ha-1 compared with 0 t ha-1,and this was significantly (P < 0.01) higher than values obtained from either 2, 6 or 8 t ha-1. Thus, the effect of the application of 4 t ha-1 was more outstanding and is recommended if high grain yields are to be obtained.KEY WORDS: Soil Acidity, Wood Ash, Growth, Nodulation, Grain Yields, Southeast, Nigeria

Effect of different levels of wood ash on soil chemical properties in an acid ultisol of Southeast Nigeria

No Abstract. Nigerian Journal of Soil Science Vol. 16 (1) 2006: pp. 109-11

Integrated Nutrient Management, Soil Fertility and Productivity of Maize (Zea mays l.) in a Derived Savanna Ultisol of Southeastern Nigeria

The response of maize to different rates of NPK 15:15:15 compound fertilizer under basal application of rice-husk ash (RHA) was evaluated in a two-year field experiments in 2009 and 2010. The RHA at 4 t ha-1 was incorporated into the soil before the application of 0, 100, 200, 300 and 400 kg ha-1 NPK. The RHA contains 64.00 g kg-1 Ca, 12.20 g kg-1 Mg, 12.50 g kg-1 P, 9.00 g kg-1 K, 2.10 g kg-1 N, 1.23 g kg-1 Organic carbon and had a pH of 10.86. Treatments were fitted in a randomized complete block design (RCBD) replicated three times. Analysis of variance (ANOVA) indicated no significant treatment effects at P = 0.05 on soil pH, Ca, P and K except for soil total N. Curve estimations show values of R2 = 0.892** for soil total N and R2 = 0.874** for grain yield of maize. Significant increase (P < 0.01) in soil total N status from 0.065 % in the control (0 kg ha-1) plots to 0.23 % at 400 kg ha-1 NPK fertilizer relate to the patterns of growth and grain yield of maize test crop. The application of 200 kg ha-1 NPK gave grain yield of 3016.67 kg ha-1 when compared with 1755.55 kg and 1944.44 kg ha-1 obtained, respectively in the control and 100 kg ha-1 NPK. Grain yield at 300 and 400 kg ha-1 NPK were not significant (P = 0.05) when compared with that at 200 kg ha-1. The application of 200 kg ha-1 NPK tended to be cost effective

Comparative effects of plant residues and NPK fertilizer on soil properties in a humid ultisol

Field experiments were conducted at two locations in 2001 and 2002 on acidic Ultisol of Southeast Nigeria to assess the effects of amending soil with plant residues on soil physical and chemical properties. The soil amendment treatments compared were natural fallow, wood ash at 6 tha-1, peanut residue at 12 tha-1, combination of wood ash and peanut residue at 6 tha-1 and 12 tha-1 respectively, and NPK fertilizer (300 kg ha-1). Incorporated wood ash, peanut residue, their combination, and fertilizer increased cation exchange capacity (CEC) compared with fallow, peanut residue increased soil N but not P. Ash increased soil P and not N, NPK fertilizer increased soil N, P and CEC. Ash and peanut residue, alone or combined, reduced soil bulk density and increased aggregate stability and porosity. Nigerian Journal of Soil Science Vol. 15 2005: 9-1