Concentration of Thiourea is effective in breaking the dormancy of potato (Solanum tuberosum L.) varieties

Abstract

Potato germination is highly sensitive to ecological conditions. High altitude and low annual average temperature result in tuber dormancy and poor sprouting. Dormancy has become a significant constraint for lowering potato production, which hinders the possibility of growing two crop cycles per year. An experiment was conducted from February to April 2020. Two major potato varieties (Desiree and Cardinal) were treated with four Thiourea concentrations (0, 1, 2, and 3%) in a two factorial, completely randomized block design with three replications. Tubers were soaked for 2 hours in different Thiourea solution as per treatments, air dried until excess solution was removed and kept in a dark room on plastic trays. With the progress of experiment dormancy breaking and sprouting parameters like early sprouting, dormancy breaking, sprout length and sprout density were recorded. It was found that Thiourea has a significant effect on all observed attributes as per varieties of potato. For Desiree variety, Thiourea (1%) decreased dormancy period by 22 days compared to control (Desiree*Thiourea 0%) and produced the longest average sprout of 7.36cm at 49 days after treatment (DAT). On the other hand, for the Cardinal variety, Thiourea (3%) decreased tuber dormancy by 27 days compared to control (Cardinal*Thiourea 0%) and produced sprout of 7.75 cm at 49 DAT. In case of sprouts/tuber 1% and 3% Thiourea produced 4.13 and 1.91 sprouts/tubers in Desiree and Cardinal, respectively. The overall mean finding indicate that, 1% and 3% Thiourea concentration was significantly superior for breaking dormancy and enhancing sprouting of potato varieties of Desiree and Cardinal respectively.