gamma-induced reciprocal mitotic recombination and gene conversion have been studied under conditions inhibiting XrapidX postirradiation recovery of diploid yeast Saccharomyces cerevisiae. It turned out that, if the first postirradiation cell division occurs at higher KCl concentrations (XrapidX postirradiation recovery is inhibited), the frequency of mitotic reciprocal recombination within the gene ADE2-centromere region decreases. Keeping of irradiated cells (in the G1 phase of the cell division cycle) in water at 28 degrees C prior to plating on the selective agar containing 1.5 M KCl leads to smaller frequency of gene conversion lys2-25/lys2-22----Lys+, as compared with that for the cells immediately plated on the selective agar. Correlation has been found between the coefficient of gene conversion frequency decrease, due to postirradiation keeping in water, and XrapidX recovery efficiency. Interpretation of the data is based on the hypothesis that recombination repair of DNA double-strand breaks induced by ionizing radiation is responsible for XrapidX postirradiation recovery.