Abstract

A field experiment was set up to investigate the effects of different sources of nitrogen on potato at Tigoni in Kenya. The treatments consisted of ten fertilizer materials and two potatoSolanum tuberosum varieties, namely, ‘Tigoni’ and ‘Asante’. The experiment was conducted for two consecutive seasons: October, 2008 to February, 2009 (first season) and April, 2009 to August, 2009, (second season). The experiment was a factorial laid in randomized complete block design with three replications. The potato yields were high with variety ‘Tigoni’ giving an average of 81.0 tons/ha in the first season and 86.8 tons/ ha in the second season. Variety ‘Asante‘yielded an average of 59.5 tons/ha in the first season and 62.1 tons/ha in the second season. The fertilizer materials, the varieties, and the interaction between fertilizers and varieties were all significant (P = 0.05) in both seasons. The experiment need to be repeated on farmers’ fields where the masking effects of the residual fertilizers can be eliminated. In addition, the cost of different fertilizer combinations needs to be evaluated so as to make the most profitable recommendations to potato growers in Kenya.

Key words: Asante, Kenya, nitrogen sources.