Effect of rice-husk ash on exchange acidity, growth and yield of groundnut (&lt;i&gt;Arachis hypogaea&lt;/i&gt; l.) in an acid ultisol.

D.O Nottidge,R.B Balogun,N.R Njoku

doi:10.4314/gjass.v8i1.48514

Abstract

Response of groundnut grown on acidic soil to rice-husk ash applied at 0, 1, 2, 3 and 4 t ha-1 was studied in two field experiments in 2005 and 2006 at Ishiagu in the derived savanna zone of southeast Nigeria. Treatments were fitted in a randomized complete block design (RCBD) replicated three times. Effects of treatments on some soil fertility and productivity parameters were evaluated. The rice-husk ash used contain 64.00 g kg-1Ca, 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. Soil pH increased from initial values of 5.16 to 6.20, while levels of exchangeable acidity correspondingly decreased from initial values of 0.80 to 0.26 cmol kg-1 with 3 t ha-1 applied rice-husk ash. Estimation of linear and quadratic curves respectively for soil pH and exchange acidity show values of r2 = 0.95 for soil pH and R2 = 0.98 for exchange acidity. Significant increases (P < 0.01) in soil P, K and Ca status relate significantly (P = 0.05) to patterns of growth and kernel yield of the crop. The 3 t ha-1 rice-husk ash is recommended. No significant yield advantage was observed at 4 t ha-1.

Highlights

Soil infertility problems in humid tropical soils of southeast Nigeria are associated with low pH, deficiency in soil organic matter, nitrogen and cations (Nottidge, 2005)
These characteristics are responsible for the response in growth and kernel yields of groundnut obtained in the field to varying levels of rice-husk ash
The response curves showing the effect of different levels of rice-husk ash on soil pH, exchange acidity and calcium are presented in Figures 1, 2 and 3

Summary

Introduction

Soil infertility problems in humid tropical soils of southeast Nigeria are associated with low pH, deficiency in soil organic matter, nitrogen and cations (Nottidge, 2005). They possess a much lower base status. The organic matter and cation exchange capacity are low and reflect the kaolinitic and oxide clay mineralogy (Enwezor, et al, 1989). In an experiment in an acid oxisol reported that an acid regime prevents the development of an effective legume-rhizobium symbiosis resulting in poor yields of peanut. Stubbiness of roots of some crops such as maize, groundnut and soybean, was ascribed to the toxic presence of soil exchangeable Al, low Ca and Mg (Igbokwe et al, 1981; Anandan et al, 1985). Stubbiness of roots of some crops such as maize, groundnut and soybean, was ascribed to the toxic presence of soil exchangeable Al, low Ca and Mg (Igbokwe et al, 1981; Anandan et al, 1985). Brady and Weil, (1999), concludes that a soil in the intermediate pH range (6.0 – 6.5) presents the most satisfactory biological regime

Methods

Results

Discussion

Conclusion