Direct and efficient plant regeneration from leaf explants of Solanum tuberosum l. cv. Bintje.

A two-step procedure was used for plant regeneration from in vitro grown leaf strips (2-3 mm wide) of cv. Bintje. Step I medium was designed with 2,4-dichlorophenoxycetic acid (2,4-D) at 0.0 or 9.0 μM, in combination with 2.28 μM kinetin (K), benzyl adenine (BA), zeatin (Z) or zeatin riboside (ZR). Step II media were 2,4-D-free media containing 5.78 μM gibberellic acid (GA3) and growth regulators similar to those of step I media. Leaf explants cultured in medium I containing zeatin riboside or zeatin for 6 days and then subcultured in medium II containing zeatin riboside produced numerous shoots without callus formation. Zeatin riboside containing step I and II media caused shoot regeneration in a high number (97.5±2.2) of explants. Approximately, 33.7±8.4 shoots were regenerated from each leaf explant.