Potato (Solanum tuberosum L.) yield and quality as influenced by cultivar and nitrogen fertilizer levels at Wolaita Sodo, Ethiopia

Abstract

Despite the food and nutritional contribution of potatoes, their production and productivity are faced with major constraints such as selection of an appropriate cultivar and fertilizer rates. A field experiment was conducted at Wolaita Soddo, in Southern Ethiopia, to identify adaptable cultivars and optimum levels of nitrogen fertilizer for potato production. The treatments consisted of three cultivars (Bellete, Gudene, and one local check) and four levels of nitrogen (N) (0, 55.5, 111, and 166.5 kg N ha-1) to give a total of 12 treatments arranged in factorial combinations and laid out in a Randomized Complete Block Design with three replications. Data was collected on growth, yield, and yield components. Results revealed that days to 50% flowering and maturity, number of marketable tubers, unmarketable tubers, marketable tuber yield, and total tuber yield were significantly influenced by the interaction effect. As the level of N increased from 0 to 166.5 kg ha-1, the days to physiological maturity were extended. The maximum marketable yield (34.15 t ha-1) was recorded from cultivar Bellete with 166.5 kg N ha-1, whereas the least (7.48 t ha-1) was obtained from local check with 0 kg N ha-1, indicating a 356.55% yield advantage with proper cultivar and fertilizer combination. In the tuber quality parameters, Bellete had the highest dry matter (23.28%) and specific gravity (1.094 g cm-1), whereas the lowest (17.65% and 1.070 g cm-1) were recorded from local. Partial budget analysis also confirmed that the Bellete cultivar with 166.5 kg N ha-1 had the highest MRR (1850), which was the most economically feasible regarding potato yield and quality. Thus, the cultivar Bellete with 166.5 kg N ha-1 can be used for potato production in the study area.