Sweet potato varieties to diversify cultivars in Bhutan

Abstract

Sweet potato (Ipomea batatas (L.) Lam) is an important root crop grown in the world. It provides carbohydrates, proteins, vitamins, fibre and essential minerals. With limited released varieties available, and the crop being undocumented thus far, sweet potato production in Bhutan is insignificant and has not gained scope in agricultural food systems. For nutrient and crop diversification, three improved varieties from Japan i.e., Beni Azumi (proposed name: Bajo Kewa ngam-I), Orange flesh (Proposed name: Bajo kewa-ngam-II), Gorojima and a local variety as a check were evaluated under three different agro-ecological zones to ascertain their performance
in terms of yield and other yield attributes. The experiment was laid out in a Randomized Complete Block Design with four treatments each with three replications. The result showed no significant difference in yields between the varieties. Nonetheless, it was observed that orange flesh variety out-yielded (13.8 t/ac) all other experimented varieties across all experimental sites. The variety orange flesh followed by Beni Azumi and Gorojima were the most preferred variety based on their yield potential, pests and diseases tolerance, organoleptic test (taste, texture and colour) and yield attributes. All three varieties showed good yield stability.