An electrophoretic study of esterase and peroxidase isozymes in Brassicoraphanus

Summary A comparative electrophoretic study of esterase and peroxidase isozymes from the leaves of Brassicoraphanus and its parental species (Brassica japonica and Raphanus sativus) was carried out by means of the polyacrylamide gel isoelectrofocusing technique. The isozyme bands of Brassicoraphanus could be regarded as a summation of parent-derived bands, some of which were missing, in addition to some new bands. The qualitative and quantitative variation of isozyme patterns among individual plants was found within each strain of Brassicoraphanus as well as each parental species. The range of the enzymatic variation of a certain strain seemed to reflect the genetic homogeneity of the strain in question. Every strain of Brassicoraphanus was less variable in esterase patterns than the parental species, but in peroxidase patterns the variations of Brassicoraphanus were intermediate between those of both parents. Some strains of Brassicoraphanus were uniform in isozyme patterns, whereas others were variable. The difference in enzymatic variation among strains was perhaps due to the difference in the source of the strains and the selection which they received.