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Substitution rate comparisons between grasses and palms: synonymous rate differences at the nuclear gene Adh parallel rate differences at the plastid gene rbcL.
It is reported that palm sequences evolve at a rate of 2.61 x 10(-9) substitution per synonymous site per year, a rate which is slower than most plant nuclear genes, and synonymous rates in nuclear Adh genes show a marked decrease in palms relative to grasses, paralleling the pattern found at the plastid rbcL locus. Expand
Plant Population Genetics, Breeding, and Genetic Resources
A resource for students and research workers in population genetics, molecular evolution, evolutionary biology, ecological genetics, forestry and crop improvement.
Regions of stable equilibria for models of differential selection in the two sexes under random mating.
The principle that the average degree of dominance controls equilibrium behavior is extended to models allowing directional selection in one sex with overdominance in the other sex, by showing that polymorphism is maintained if and only if the average fitness in heterozygotes exceeds one. Expand
Genetic evidence for a second domestication of barley (Hordeum vulgare) east of the Fertile Crescent
  • P. Morrell, M. Clegg
  • Biology, Medicine
  • Proceedings of the National Academy of Sciences
  • 27 February 2007
Differences in haplotype frequency among geographic regions at multiple loci are used to infer at least two domestications of barley within the Fertile Crescent and a second 1,500–3,000 km farther east, both of which contributed to diversity in European and American cultivars. Expand
The Nature of Nucleotide Sequence Divergence between Barley and Maize Chloroplast DNA.
Compared to spinach chloroplast DNA, the barley rbcL-atpB untranslated region is extremely diverged, with only the putative rBCL promoters and ribosome-binding site being extensively conserved. Expand
Low levels of linkage disequilibrium in wild barley (Hordeum vulgare ssp. spontaneum) despite high rates of self-fertilization.
It is demonstrated that, for the majority of wild barley loci, intralocus LD decays rapidly, i.e., at a rate similar to that observed in the outcrossing species, Zea mays (maize). Expand
Relative rates of nucleotide substitution at the rbcl locus of monocotyledonous plants
Grasses have the most rapid substitution rate and the pattern of rate variation is consistent with the generation-time-effect hypothesis, which has important implications for phylogenetic reconstruction. Expand
Measuring Plant Mating Systems
Plants exhibit a wide variety of mating structures including (a) regular systems of inbreeding and frequently self-fertilization; (b) negative assortative mating due to various kinds of incompatibility systems; and (c) effective inbreeding due to the clustering of related individuals within a small neighborhood. Expand
Evolution of alcohol dehydrogenase genes in the palm and grass families.
Comparison of the Adh gene families from palms and grasses shows that theadh1 and adh2 genes of grasses, and the adhA andadhB genes of palms, arose by duplication following the divergence of the two families. Expand