Several species in the genus Peperomia Ruiz & Pav. have giant chloroplasts in the palisade parenchyma of their leaves. Because of this unique feature, Peperomia metallica L. Linden & Rodigas has become a valuable model plant for studying plastid biology. However, the use of Peperomia for molecular studies has been limited by the lack of efficient regeneration and transformation protocols. In this work, we aimed to develop a reliable regeneration system for Peperomia from leaf explants. | Research Article Turk J Bot 34 (2010) 329-334 © TÜBİTAK doi: Development of a highly responsive leaf-based regeneration system for Peperomia species Mohammad AHMADABADI1,2,*, Ralph BOCK1 1 Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm - GERMANY 2Azarbaijan University of Tarbiat Moallem, 35 km Tabriz-Maraqeh Road, Tabriz - IRAN Received: Accepted: Abstract: Several species in the genus Peperomia Ruiz & Pav. have giant chloroplasts in the palisade parenchyma of their leaves. Because of this unique feature, Peperomia metallica L. Linden & Rodigas has become a valuable model plant for studying plastid biology. However, the use of Peperomia for molecular studies has been limited by the lack of efficient regeneration and transformation protocols. In this work, we aimed to develop a reliable regeneration system for Peperomia from leaf explants. Using MS medium complemented with different combinations of phytohormones, a highly efficient in vitro regeneration protocol was developed for P. metallica and P. peduncularis, another species with giant chloroplasts. Regeneration occurs through direct organogenesis from leaf discs at a very high frequency. Our protocol can provide a reliable tissue culture system for future Peperomia genetic transformation experiments. Key words: Peperomia, tissue culture, giant chloroplast, regeneration, gibberellic acid Introduction The genus Peperomia belongs to the family Piperaceae and comprises approximately 1500-1700 mostly tropical species, making it one of the largest genera of basal angiosperms (Wanke et al., 2006). Several species of Peperomia grow quickly and vary considerably in appearance, making them a fine choice for gardeners. A few species are also popular as house plants. One well-known species in the genus is Peperomia metallica, which was reported to contain giant chloroplasts in its palisade parenchyma cells (Schürhoff, 1908) .
