The Journal of Heredity 1984:75(6):453-456
© 1984 The American Genetic Association 75:453-456
research-article |
Enzyme activities and growth rates in two sunfish species and their hybrids
Department of Genetics and Development, University of Illinois Urbana, IL 61801
Aquatic Biology Section, Illinois Natural History Survey, Champaign, IL 61820, and the Department of Animal Science, University of Illinois Urbana
Department of Genetics and Development, University of Illinois, Urbana, and the Aquatic Biology Section, Illinois Natural History Survey Champaign, IL 61820
Please address reprint requests to Dr. G. S. Whitt
Abstract
Intra- and interspecific crosses involving green sunfish (Lepomis cyanellus) and redear sunfish (L. microlophus) were made to produce progeny of each parental species and reciprocal hybrids. The differences in growth rates of different progeny classes were determined and related to their differences in tissue enzyme activities. After one growing season, redear
× green
hybrids showed the greatest growth (average weight gain) followed by that of green
× redear
hybrids, redear and green sunfish. At the end of the second growing season, green
× redear
hybrids had the highest average weight followed by redear
× green
hybrid, redear and green sunfish. Specific activities of different enzymes (malate dehydrogenase, lactate dehydrogenase, glucosephosphate isomerase and phosphoglucomutase) in one or more tissues (skeletal muscle, liver, and eye) also differed among the progeny classes. No significant correlation was observed between growth and the tissue levels of enzyme locus expression. Enzyme activity levels of hybrids tended to be intermediate to those of parental species, whereas growth rates of each hybrid exceeded parental growth rates. Apparently, alterations of gene regulation in the hybrids are exerting different effects upon these morphological and molecular traits.