Asian Journal of Soil Science and Plant Nutrition

Aim: The aim of investigation was to evaluate the influence of organic fertilizer on soil, leaf nutrient content, growth and yield of Physic nut in Makurdi, North Central, Nigeria.

Study Design: The experiment was laid out in a randomized complete block design and replicated trice.

Place and Duration of the Study: Field experiment was carried out at Teaching and Research Farm of the University of Agriculture, Makurdi, Nigeria during 2009 and 2010 cropping seasons.

Methodology: The trial consisted of four treatments: organic fertilizer (Nomau®) at rate of 0, 0.50, 0.75 and 1.00 t ha^-1. Soil samples were collected from the plough layer (0 – 20 cm) at the beginning of the experiment as composite. After harvest of the first and second cropping seasons, soil composite samples were collected on the basis of treatments for routine chemical analysis. The Nomau® manure was incorporated into the soil two weeks before planting physic nut. Parameters measured at three weeks intervals number of primary branches, plant height and leaf area and yield at the end of cropping season.

Results: Organic fertilizer is an important contribution of organic matter that improves the physical and chemical characteristics of the soil. The soil at the experimental site had soil pH which was adequate for producing most crops in the tropics, low in organic matter, available phosphorus, cation exchange capacity, exchangeable calcium, potassium and Magnesium. It increased SOM, N, P, Mg, K, Na and CEC. Its application significantly increased number of primary branches, plant height, leaf area, leaf N, P and K concentrations of physic nut and yield relative to control.

Conclusion: The findings from the experiment shows that maximum production of physic nut and soil sustainability can be achieved from treatment 1.00 t ha^-1 if properly managed in Markudi, Nigeria.