The inheritance of alcohol dehydrogenase isozymes in seeds of hexaploid Echinochloa crus-galli Beauv.

Abstract

To clarify the mode of inheritance of alcohol dehydrogenase (ADH) isozymes in Echinochloa crus-galli, we induced single-banded mutant lines for ADH by gamma-ray irradiation; the irradiation of the 5-banded E. crus-galli var. formosensis (phenotype A1A2A3A4A5) produced two single-banded mutant lines, A1 and A5. All pairwise reciprocal crosses were made among the single-banded mutant lines and the naturally occurring single-banded type E. crus-galli var. praticola that displays only band A3. The ADH zymograms from the resulting F1 progenies were identified by polyacrylamide gel electrophoresis and the relative staining densities of the bands were determined by densitometer scanning for several important E. crus-galli phenotypes and F1 individuals. All F1 seeds displayed both parental bands plus an additional band located intermediate to the parental bands. Moreover, the ratios of the band densities were in agreement with those expected from the kinetics of ADH dimer formation. The results can be accounted for by three loci encoding three ADH subunits. Also, the data indicate that the A3 band of the 5-banded phenotype consists of two different dimeric products, homo- and hetero-dimers.