Resistance responses of plants regenerated from tomato anther and somatic tissue cultures to Clavibacter michiganense subsp michiganense

The production of gametoclonal and somaclonal variants in tomato is of grea t importance for the genetic improvement of tomato hybrids and cultivars. T he possibility to obtain tomato plants resistant to Clavibacter michiganens e subsp. michiganense (Cmm) through anther and tissue culture was investiga ted in the present study. Regenerants from anther and tissue cultures and t heir progenies (R-1-R-3) in the cultivars Roma ins and Bella, lines L. 24-1 3, and L. 6944, as well as the hybrids Roma ms x UC 82A, Roma ms x L. 31, R oma ms x Bella, and Cristy, were tested for resistance to Cmm. The regenera nts differed in their resistance to Cmm. All regenerants from the anther cu lture of the genotype Roma ms and Roma ms x UC 82A are susceptible to the d isease, while those from Bella and Roma Ins x L. 31 vary from susceptible t o resistant. The highest number of regenerants obtained from somatic tissue culture lacking disease symptoms until the end of the vegetation was obser ved in the genotypes Cristy and L. 24-13. Variation in regenerant resistanc e is found in R-1, R-2, and R-3. The results suggest that the gametoclonal and somaclonal variation may be efficiently applied to obtain tomato plants resistant to Cmm.