Yield Performance of Popcorn (Zea mays L. everta) under Lime and Nitrogen Fertilization on an Acid Soil

A two-year field experiment was carried out on the acidic coastal plain sands of South Eastern Nigeria during the year 2009 and 2010 planting seasons to study the effect of lime levels (L = 0, 500 and 1000 kg ha-1) and nitrogen rates (N = 0, 40, 80 and 120 kg ha-1) on -popcorn varieties (Yellow composite and Ashland). Results showed that N application resulted in significantly (p=0.05) higher grain yield at 80kg N ha-1 in 2010 than that obtained at 120 kg Nha-1 in 2009. Yield in 2010 outstripped yield in 2009 by 23.65%. Results also showed that lime at 500 kg ha-1 gave the highest popcorn yields in 2010, a yield increase of 18.03 % above control, whereas there was no yield response to lime in 2009. Based on the results obtained, it can be concluded that popcorn sown at 80 kg N ha-1 and 500 kg ha-1 rates of lime significantly increased the crop productivity compared to those sown at other N and lime rates. The study demonstrated the effect of lime amendment in reducing rates of inorganic N applied to popcorn especially with resource poor farmers who form the bulk of maize producers in Nigeria.