Publications by authors named "Ron J Okagaki"

Until the mid-1950s, it was believed that genetic crossovers did not occur within genes. Crossovers occurred between genes, the "beads on a string" model. Then in 1956, Seymour Benzer published his classic paper describing crossing over within a gene, intragenic recombination.

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The shoot apical and axillary meristems control shoot development, effectively influencing lateral branch and leaf formation. The barley () () mutation blocks axillary meristem development, and mutant plants lack lateral branches (tillers) that normally develop from the crown. A genetic screen for suppressors recovered two recessive alleles of () that partially rescued the tillering phenotype.

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Vegetative axillary meristem (AXM) activity results in the production of branches. In barley (Hordeum vulgare L.), vegetative AXM develop in the crown and give rise to modified branches, referred to as tillers.

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Barley (Hordeum vulgare L.) carrying recessive mutations at the Low number of tillers1 (Lnt1) gene does not develop secondary tillers and only develops one to four tillers by maturity. Double mutant analysis determined that the lnt1 mutant was epistatic to five of the six low and high tillering mutants tested.

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Oat-maize addition (OMA) lines with one, or occasionally more, chromosomes of maize (Zea mays L., 2n = 2x = 20) added to an oat (Avena sativa L., 2n = 6x = 42) genomic background can be produced via embryo rescue from sexual crosses of oat x maize.

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Barley (Hordeum vulgare L.) carrying the recessive mutation absent lower laterals (als) exhibits few tillers and irregular inflorescence development. To gain an increased understanding of the genetic control of tillering in barley, we conducted morphological, genetic, and transcriptome analysis of the als mutant.

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Centromere positions on 7 maize chromosomes were compared on the basis of data from 4 to 6 mapping techniques per chromosome. Centromere positions were first located relative to molecular markers by means of radiation hybrid lines and centric fission lines recovered from oat-maize chromosome addition lines. These centromere positions were then compared with new data from centric fission lines recovered from maize plants, half-tetrad mapping, and fluorescence in situ hybridizations and to data from earlier studies.

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We have developed from crosses of oat (Avena sativa L.) and maize (Zea mays L.) 50 fertile lines that are disomic additions of individual maize chromosomes 1-9 and chromosome 10 as a short-arm telosome.

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A large amount of repetitive DNA complicates the assembly of the maize genome sequence. Genome-filtration techniques, such as methylation-filtration and high-CoT separation, enrich gene sequences in genomic libraries. These methods may provide a low-cost alternative to whole-genome sequencing for maize and other complex genomes.

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