Plants, unlike animals are naturally able to synthesize whatever compounds they need, require more than a dozen different elements [majorly Nitrogen, Phosphorus and Potassium (NPK)] as such. This study investigated the effect(s) of application of cow dung (CD) and NPK fertilizer on the early growth response of Irvingia gabonensis. Top soil samples of between 0 – 15 cm depth (control group I), top soil + NPK (Group II), top soil + cow dung (Group III) and top soil + NPK + cow dung (Group IV) were collected at varying combinations. The soils were then taken to the laboratory for physio-chemical analysis of key components [pH, N, P, K+, Ca2+, Mg2+, Na+, Org. C, sand, silt and clay]. Prior to and after actual experimentation, the N, P, K, Ca, Mg, Na, pH constituents of the cow dung were also analysed. For every two weeks (in twenty weeks duration) after application, plant heights, leaf area, number of leaf, stem girth were obtained and noted. By way of a sensitive weighing machine, 20 WAP destructive sampling was conducted to determine the weights of the shoot and root after oven-drying for three days in an oven sets at 75°C. In any case, these samples were then analysed for the nutrient content of the stem, root and leaf. Following data collection, comparisons of mean differences was performed using the Fishers protected least significant test and Duncan Multiple Range Test (DMRT) at 5% level of probability. Upon careful observation of result, study found that Irvingia gabonensis seedlings grown with cow-dung and NPK combination (Group IV) performed better in growth (height, diameter and leaf area) than seedlings grown in only top soil medium (TS) with single fertilizer use (Group II). However, NPK 3 CD 3, NPK 3 CD 2 and NPK 2 CD 3 best support the early growth phase of Irvingia gabonensis seedlings as compared to others. Study therefore showed Cow dung to contain substantial amount of essential elements that may be beneficial for the physio-chemical growth of Irvingia wombolu seedlings and combating reports of deforestations across the globe. It is recommended that for better results, cow-dung and NPK mixtures should be used than single use of the either treatments. Further studies aimed at corroborating this research are also recommended.
Effects of soil amendments on survival and early growth of three timber species grown on sand tailings in the peninsular Malaysia