Mehdi Younessi-Hamzekhanlu - Department of Agronomy and Plant Breeding Sciences, College of Aburaihan, University ofTehran, Tehran-Pakdasht, Iran, P.O. Box: 3391653755
Ali Izadi-Darbandi - Department of Agronomy and Plant Breeding Sciences, College of Aburaihan, University ofTehran, Tehran-Pakdasht, Iran, P.O. Box: 3391653755
Mohammad Ali Ali Malboubi - ran, Tehran-Pakdasht, Iran, P.O. Box: 3391653755.2. Department of Plant Biotechnology, National Institute of Genetic Engineering andBiotechnology,Tehran, Iran, P.O. Box: 14965/161
Mohsen Ebrahimi - Department of Agronomy and Plant Breeding Sciences, College of Aburaihan, University ofTehran, Tehran-Pakdasht, Iran, P.O. Box: 3391653755

Direct regenerations by using mature cotyledonary node as a explants has been shown to be time-savingand convenient strategy for micropropagation of soybean. So we have evaluated regeneration protocolthrough single shoot using cotyledonary node as a rapid and efficient protocol for two soybean cultivarsand one mutant line. Cotyledonary nodes explants obtained from 7-days-old in vitro seedlings. After 28days, the percent of regeneration and after 42 days, regeneration area were calculated. The results showedthat percent of regeneration and regeneration area of mutant line was significantly more than twocultivars, L17 and Williams. After shoot induction, plants were transferred to shoot elongation mediumfollowed by transferring plants to rooting medium. The results showed that the percent of rooting was notsignificantly affected by genotypes. In another experiment to test kanamycin sensitivity of regeneratedshoots, it was found that kanamaycin with 150 mg/L concentration is lethal for regeneration of soybeanshoots from cotyledonary node explants. The results showed that regeneration efficiency of mutant linewas significantly more than two other cultivars. Kanamaycin sensitivity of regenerated shoots showedthat kanamycin at 150 mg/L or above can be used as a selective agent for all three tested cultivarstransformation

Cotyledonary node, Mutant, Regeneration, Soybean