Effects of teak canopy cover and npk fertilizer application on growth of ginger in agroforestry trial, Ile-Ife, Nigeria
Non-timber forest products issues are of global interest due to their importance among rural and urban dwellers for income, healthcare and food security. This study investigates the effects of Tectona grandis canopy cover and NPK (Nitrogen, Phosphorus, Potassium) fertilizer (15:15:15) application on growth parameters of Ginger (Zingiber officinale Roscoe, Zingiberaceae) in Ile-Ife, south-western Nigeria. Twelve replicates of ginger plots (6m²each) were laid in a completely randomised block design within and outside Teak plantations. Six replicates were treated with NPK (15:15:15) in a split dose at two and 6 weeks old, while others serve as control. Growth indices such as foliage, tiller numbers, and plant height per plot were obtained for two cropping seasons. Data obtained were analysed using ANOVA and descriptive statistics. Tiller formation in ginger was significantly inhibited by Teak canopy with or without NPK fertilizer (0.000 and 0.033, ρ ≤ 0.05). Ginger heights were not significantly different within Teak plantation with or without NPK (0.647); however, there were significant differences between heights of ginger grown within and outside Teak plantations, (0.000 and 0.011, ρ ≤ 0.05). Foliage production in ginger was higher outside teak plantation, (0.000 and 0.007, ρ ≤ 0.05), while NPK also enhanced foliage production in ginger significantly, (0.000, ρ ≤ 0.05). The study concluded that incorporation of Ginger in plantations such as Teak and other fast growing indigenous species can enhance plantation benefits in terms of biomass yield. Further research in this area is recommended in agroforestry systems.
Keywords: Ginger, Teak canopy, tiller formation, leaf production, agroforestry.