ABSTRACT

A greenhouse study and one field experiment were conducted between 2006 and 2007 to evaluate the fertility status of soils of Cross River State for Ginger (Zingiber Officinale Roscoe) Production. The soils for the greenhouse study were collected from fifteen (15) locations (Akamkpa, Mfamosing, Obubra, Ediba, Akpet I, Bawop, Betukwel, Bishere, Ogoja, Ugep, Creek Town, New Netim, Ikot-Omin, Nde and Bendeghe) to represent the five major parent material in the state namely; Basement Complex, Shale, Sandstone, Coastal Plain Sand and Basalt and the two ginger varieties used were the UG I (Yellow ginger) and UG II (black ginger). The greenhouse experiment was a split-plot design with three replicates, the ginger varieties occupied the main plot and the fifteen soil types the subplot while the experiment on NPK fertilizers requirements was laid out in a randomized complete block design with the three replications with each experiment located at Akamkpa (Basement Complex) and Obubra (Shale). The plant parameters accessed included plant height, number of leaves, number of shoots, leaf area, fresh weight of plants, rhizome yield and nutrient uptake. The result obtained showed that the soils were acidic with p1-I values ranging from 3.80 — 5.50, sandy and generaJly low in nutrients except the soils derived from Basement complex parent material. Rhizome yield in the green house studies in the various locations showed that soil from Akamkpa performed best followed by the soils of Mfamosing and Akpet I for the UG I variety with the following fresh rhizome weights 72.3, 69.1 and 61.6gm5 while the soils from Akamkpa also performed best followed by the soils of Ugep and Bendeghe for the UG II variety with the following fresh rhizome weights 67.8, 64.3 and 48.8gms. The UG I variety had higher yield compared to UG II variety. Exchangeable potassium correlated significantly with rhizome yield (r = 0.654*). Extractable boron correlated significantly with the number of shoots of the UG I variety (r = 0.492*) while the plant height of UG I variety had significant correlation with organic matter (r = 0.513*) and total nitrogen (r = 0.599*). The significant and positive correlation between plant height, number of shoots of the two ginger varieties and fresh rhizome yield is an indication that these plant parameters are great contributors to the yield of ginger. The results of the field study indicated that NPK treatment combination of 200 80 100 kg/ha was most suitable for ginger production in the state. While ginger performed better in Obubra in terms of fresh rhizome yield, the average fresh rhizome yield of 8.10 tones per hectare was 21% higher than the yield at Akamkpa.