Effects of Biochar and Compost on Cocoa (Theobroma Cacao) Seedlings Growth

Abstract— The research was carried out at the experimental field of the Kumasi Institute of Tropical Agriculture (KITA) to evaluate the effect of biochar and compost on the growth of cocoa seedlings. There were four (4) treatments including biochar, compost, a combination of biochar + compost, and a control. Treatments were applied at a rate of 0 g (control), 60 g compost, 60 g biochar, and 30 g each of biochar and compost combination into 60 kg soil in polybags. The treatments were laid out in a randomized complete block design (RCBD) with three replications. Data were collected on the number of leaves, plant height, stem girth, and leaf area, all analyzed using analysis of variance. Significant treatment means were separated LSD at P≤0.05. The analysis of variance indicated significant differences among treatment types in plant height (P<0.00001), the number of leaves (P<0.034), stem girth (P<0.044) and leaf area (P<0.012). The highest seedlings height was recorded in soil amended with biochar (55.3 cm) and the least in the control (28.1 cm). Soils amended with compost (15.3) recorded the highest numbers of leaves while a relatively low number was recorded by control (9.0). Stem girth was very high in soils amended with compost+biochar (0.76 mm) and the least in the control (0.62 mm). The highest leaf area was recorded in soils amended with biochar (84.6 cm²) while the control recorded 57.0 cm². It can be recommended that the application of 60g biochar influences significantly growth parameters of cocoa seedlings at nursery.