The formation of cucumber resistant plants Cucunzis sativus of Rhizoctonia solani calves and stems

In this study callus stimulated from cotyledons and stem explantsof cucumber seedlings on MS media supplemented with 2.0 mg/L of BAand 1.0 mg/ L of NAA for cotyledons , while in stem MS mediacontaining 1.0 mg/L from BA and NAA were used . Selection of resistantcallus to the virulent strains of Rhizoctonia so/ani was examined fromculture of cotyledons and stem medium contained the concentrations 1.0,5.0, 10.0, 15.0, 20 and 25% of fungal filtrates. The best concentrationswhich allowed selection after three cycles ( 20 days I cycle) of selectionswere 10 and 15% . The resistant callus showed a high level ofperoxidases enzymes activity . Resistance callus of cotyledons and stemswere regenerated on MS medium containing 4.0 mg/L of BA and 0.1mg/L NAA in spite of reduction of the regeneration ability of the resistantcallus up to half in cotyledons and stems compat~d-with the controlplants. Regenerated stems formed roots on MS medium without grouthregulators . Cucumber plants regenerated from callus tolerating toxicfiltrates exhibited resistance when infected with pathogenic fungi .