TRANSFORMATION OF POTATO (SOLANUM-TUBEROSUM L) USING TUBER DISCS AND STEM EXPLANTS

Abstract

Transformation of three potato cultivars (Desiree, Isola and Anac) was achieved using tuber discs and callus tissue derived from cultured stems via co-cultivation with Agrobacterium tumafaciens Ti plasmid based vectors. Neomycin phosphotransferase (NPT II) marker and beta-glucuronidase (GUS) reporter genes were used in transfer-optimization studies. First selection of transgenics was done on selective Murashige and Skoog (MS) media containing 100 mg/l kanamycin and 500 mg/l cefotaxime. Histochemical assays were done for GUS activity using X-Gluc substrat. In addition polymerase chain reaction based Southern blot analyses revealed the existence of the transferred genes. The highest transformation frequency (10%) was obtained with cultivar Desiree in MS media supplied with 5 mg/l zeatin riboside and 1.5 mg/l indolacetic acid However; Anac gave the lowest frequency using tuber discs (3% and stem explants (2%). This protocol could be useful for the improvement of potato through gene manipulation.