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F W Allendorf

Publications and source records attributed to F W Allendorf.

9 recordsLinked to original sources
PubMed1979

Inheritance of isozyme variation and heterozygosity in Pinus ponderosa.

Techniques are presented to detect 23 isozyme loci in the long-lived perennial plant, ponderosa pine. Meiotically derived megagametophyte from seeds is used to examine directly the segregation of allelic variants. Approximately seven seeds were initially examined for 12 enzymes from each of 47 trees from ten stands throughout the northern Rocky Mountain region. Additional seeds were also examined from selected families to confirm the inheritance of observed electrophoretic variants at 13 polymorphic loci and to estimate linkage relationship. Significant norandom segregation was consistently detected for three pairs of loci: ADH-1:AAT-2, ADH-1:PGI-1, and LAP-2:6PG-1. Preliminary estimates of population parameters reveal a relatively high average heterozygosity (H = 0.123). This is partitioned into a high amont of genetic variation within local stands, with only approximately 12% of the total heterozygosity resulting from genic difference between stands.

Gene Frequency↗
PubMed1979

Genetic basis of creatine kinase isozymes in skeletal muscle of salmonid fishes.

The genetic basis of isozyme phenotypes of creatine kinase (CK) from extracts of skeletal muscle of salmonids has been resolved through breeding data including double heterozygous crosses and backcrosses of rainbow trout (Salmo gairdneri), and backcrosses of coho salmon (Oncorhynchus kisutch). The two-three-, or four-banded phenotypes of homozygous individuals and all heterozygous and hybrid phenotypes of ten salmonid species are readily explained by the following model: (1) there are no detectable heterodimers either between allelic products at a single locus or between loci: (2) each allele is represented electrophoretically by two bands, presumably a reflection of stable posttranslational modification of a single polypeptide unit; (3) CK of salmonid muscle is encoded by two loci--CK-1 and CK-2. The distance separating the paired bands reflecting each allele provides a basis for two groupings--a broad-spaced group (including all species of Oncorhynchus tested excepting O. masou) and a narrow-spaced group (including all species of Salmo tested and O. masou). The relationships among species suggested by the relative mobilities and spacings of these CK bands are consistent with taxonomic schemes inferred from morphological, cytogenetic, and other isozymic data.

Animals↗
PubMed1979

Reproductive isolation with little genetic divergence in sympatric populations of brown trout (Salmo trutta).

Two reproductively isolated demes of brown trout coexist in a small Swedish mountain lake, Lake Bunnersjörna. We electrophoretically examined 102 specimens from that lake for 27 enzymes encoded by 54 loci. The two demes are fixed for different alleles at a lactate dehydrogenase locus (LDH-1); statistically significant allele frequency differences at five other loci further support the complete lack of gene flow between these demes. There are significant differences in growth rates between fish in the two demes, but no further morphological differentiation h-s been detected.--In light of these findings, the genetic distance between these populations is surprisingly small (Nei's I = 0.975). These demes represent one of the least genetically divergent, reproductively isolated sympatric pair of vertebrate populations that have been identified. The results are discussed from both an evolutionary and ecological perspective.

Alleles↗