An Improved Method for Cultivar Identification in Radish (Raphanus sativus L.) Using M13-Tailed Primers

Radish is an important root vegetable in the world, and many cultivars have been developed with various molecular marker systems to identify these cultivars. Recently developed markers for radish cultivar identification require only 11 primer pairs, but they still use conven tional PCR with different annealing temperatures and time-consuming gel electrophoresis. To improve the genotyping method, we applied touchdown PCR with 11 primers with M13 tails among 105 radish cultivars. Touchdown PCR successfully generated amplicons in all 11 M13-tailed prim ers with a condition of annealing temperature starting from 55℃, decreased by 1°C and 33 cycles at 53°C. The 11 M13-tailed primers followed by fragment analysis produced 71 amplicons, which pro duced more amplicons than gel electrophoresis that produced 23 amplicons. Especially, simple sequence repeats produced more amplicons, 12 on average, than the other marker types. The pres ent study requires less effort and provides more accurate results compared to genotyping using gel electrophoresis. Besides, a database can be established using digitized genotyping results among radish cultivars.