Effects of N, P and K fertilizer levels on plant characters and yield of ginger (Zingiber officinale roscoe) in two locations in Cross River State of Nigeria
Field trials testing the effect of five rates each of N, P and K application on UGI variety (yellow ginger) were conducted in two separate locations of Akamkpa (rainforest zone) and Obubra (derived savanna zone) in Cross River State of Nigeria. The soils of Akamkpa are formed from Basement complex (Typic Dystropept) while that of Obubra are formed from shale (Lithic Dystropept). The soils for the trials were generally low in total nitrogen and organic carbon while phosphorus was higher in the Obubra soils ranging from 15.75 to 25.16 mgkg-1 compared to Akamkpa with a range of 7.04 to 15.05 mgkg-1. No distinct trend was observed in the cation content of the studied soils. The experiment was laid in a split plot design with three replications. Agronomic parameters such as plant height, number of leaves, number of shoot, leaf area and fresh rhizome yield were taken. The result showed that the tallest plants with more leaves and
shoots were produced with higher rates of N at Obubra while the largest leaf area was produced at Akamkpa. The trend in growth and yield parameters showed that ginger performed better in Obubra than in Akamkpa and rhizome yield were also better in 2007 with lower amount of rainfall in the two locations. The study therefore confirmed that the optimum NPK treatment combination of 200:80:150 kg/ha gave the best rhizome yield during the trials.
Key words: N, P and K fertilizers, soil properties, fertility status, growth parameters, yield