Somaclonal variation for resistance to Verticillium dahliae in potato (Solanum tuberosum L.) plants regenerated from callus

Summary Plant tissue culture is recognized as an important tool to generate useful genetic variability for crop improvement. Regenerated plants from callus induced from stem explants of Solanum tuberosum cv Désirée were assessed by in vitro selection, for resistance to Verticillium dahliae. This fungus is the causal agent of Verticillium wilt, a serious vascular wilt disease both in crops and wild species.The rate of in vitro multiplication by single node cuttings was used as a parameter of screening in two selection cycles with different concentrations of V. dahliae filtrate. One resistant clone was selected and then evaluated by inoculation in the growth chamber. Induced damage, and morphological traits (dry weight, leaf area and tuber production) were estimated. The selected clone was comparable to the resistant control, cv Kondor.The results suggest that genetic variation induced in tissue culture cound be utilized to generate disease resistance.