Effect of Plant Growth Regulation during in vitro Phase on Potato Minituber Production

ABSTRACT: One of the main limiting factors for potato production in the world is shortage of certified seed tubers. The aim of our study is determining the best plant growth regulators (PGRs) and its most efficient in vitro concentration for investigation the secondary effect of PGRs on potato minituber production in green house condition we design this study. Treatment included 4 concentration of Coumarin (CO) (15, 20, 25 or 30 mg/l), Paclobutrazol (PTZ) (0.001, 0.01, 0.1 or 0.5 mg/l), Thidiazuron (TDZ) (0.01, 0.1, 0.5 or 1 mg/l) and Etephon (ET) (0.5, 1, 2 or 3 mg/l) with 4 potato cultivars: Agria, Boren, sante and Savalan were tested. Results of lab experience showed Sante produced much more minituber number (MTN) produced compared to other cultivars. The best PGR for optimum enhancement of MTN was ET. The most efficient level of ET for significant increase in MTN was (2 and 3 mg/l). PTZ produced the least amount of minituber. In the other hand, 0.001 mg/l of PTZ produced minitubers that had more size and weight compared to control