REARRANGEMENT OF HIGHLY REPETITIVE GENOMI C DNA OF BARLEY UNDER IN-VITRO CULTIVATION

A molecular analysis of plant material obtained during in vitro cultiv ation of embryogenic tissue of three barley cultivars was performed us ing cloned highly-repetitive sequences (HRS) of DNA of barley Hordeum vulgare. New fragments absent in seedling DNA of the studied species w ere revealed in DNA of in vivo embryos of H. marinum and H. jubatum as a result of hybridization with one of the HRSs. Blot hybridization an alysis of DNA from calluses and regenerated shoots did not reveal stru ctural rearrangement of HRSs. However, a significant decrease in the q uantity of the two most abundant DNA sequences in calluses and regener ated shoots of H. marinum and H. jubatum was fixed by the dot hybridiz ation method. At the same time, a significant amplification of a plasm idlike DNA sequence was revealed in a suspension culture of H. marinum . The obtained results evidence a determining role of plant genotype i n the character of alterations occurring in vitro.