EN
<Esterase isoenzymes> in roots epicotyls and leaves of 5-, 6-, and 7-week-old Brassica seedlings were studied. No variation in isoesterase phenotypes was found between individuals within the examined cultivar. Differences in the number and intensity of isoesterase bands between the investigated organs were observed. Distinctive isoesterase patterns were evaluated for each organ. Some esterase isoenzymes are proposed as markers of particular organs: EST 1/1 and EST 1/2 for leaves, whereas EST 2/2 and EST 2/3 for roots. Further studies be aimed at using different organo-specific isoesterase forms as markers of early stages of in vitro organogenesis in Brassica callus tissue culture.