Growth and Yield Characteristics of Five Different Sweet Potato Varieties Grown in the Guinea Savanna Ecological Zone of Ghana

Abstract

Aim: To determine the growth characteristics of five sweet potato varieties on different soil types as well as how they each relates to tuber yield. This investigation will help guide farmers from resource-limited areas to select varieties that grow well in austere soils to produce good yield of tubers, thereby boosting global food security. 
 Study Design: Randomized complete block design (RCBD) with five treatments and three replications.
 Place and Duration of Study: Experimental field of Bolgatanga Technical University for five months.
 Methodology: Planting was done by inserting 10 cm length of each 30 cm long soft wood vine cutting into the soil, followed by watering. Five vine cuttings planted per ridge at a spacing of 60cm. Vine cuttings were transplanted in the same order on each ridge. There were 15 plants per treatment, so seventy-five (75) for the five treatments.
 Results: Analysis of the soil showed sandy loamy soil with suitable pH of 6.05. The Orange flesh and Agric white varieties had the largest and smallest leaf areas of 177.76 cm2 and 110.74 cm2 respectively. Leaf area was positively correlated with root tuber mass in only the Red local variety (r = 0.026). Petiole length of the Orange flesh variety (19.08 cm) was significantly longer than that of the Agric white (13.55 cm, p = 0.02), Agric orange flesh (13.85 cm, p = 0.04), Red skin (11.84 cm, p = 0.00) and Red local (12.18 cm, p = 0.00) varieties. Petiole length was positively correlated with tuber yield in only the Orange flesh variety (r = 204). The Red skin (174.28 cm) and Red local (172.46 cm) varieties had the longest vines than all the rest, though not statistically significant (p = 0.241). Root tuber yield of the five varieties were Agric white (1.22 Kg), Agric orange flesh (1.40 Kg), Red skin (4.27 Kg), Red local (2.96 Kg) and Orange flesh (5.72 Kg), which were significantly different from each other (p=0.05). 
 Conclusion: The Orange flesh variety had the largest leaf area, longest petioles and the highest root tuber mass. On the other hand, the Agric white variety recorded the least Leaf area, Vine length and Tuber mass while the Red skin variety had the shortest Petioles.