An-Najah Staff

Effect of different levels of 6-benzylaminopurine (RAP) and naphthaleneacetic acid (NAA) and BAP and sucrose on in vitro shoot (SH) proliferation and microtuberization of 'Spunta' potato was studied using virus-free plantlets on modified Murashige and Skoog (MS) media. NAA at 2.0 mg 1^-1 and RAP at 0.5 mg rl resulted in the longest main SH (22 em) with highest node numbers (23 nodes). A maximum of 15 axillary SHs per main SH was produced after 10 weeks of incubation on the modified MS proliferation media in presence of 2.0 mg 1^-1 RAP and 0.1 mg 1^-1 NAA. Sucrose at 40 g 1^-1 when associated with 0.1 mg r 1 RAP was optimal for obtaining the maximum number of microtubers (MTs) in vitro. Severn MTs per SH and 1.35 MTs per node were obtained after 20 and 8 weeks, respectively. Largest MT weight and size resulted from media with 80 g 1^-1 sucrose supplemented with 0.1 mgr' RAP. On basis of space required and media used, single nodal cuttings with leaf (SNCs) seem to be more applicable for induction of MTs in vitro; contamination hazards are also reduced.