Copy numbers of four photosynthesis-related genes, PhyA, Ppc, RbcS and Lhcb1 (*)1, in wheat genomes were estimated by slot-blot analysis, and these genes were assigned to the chromosome arms of common wheat by Southern hybridization of DNA from an aneuploid series of the cultivar Chinese Spring. The copy number of PhyA was estimated to be one locus per haploid genome, and this gene was assigned to chromosomes 4AL, 4BS and 4DS. The Ppc gene showed a low copy number of small multigenes, and was located on the short arm of homoeologous group 3 chromosomes and the long arm of chromosomes of homoeologous group 7. RbcS consisted of a multigene family, with approximately 100 copies in the common wheat genome, and was located on the short arm of group 2 chromosomes and the long arm of group 5 chromosomes. Lhcb1 (*)1 also consisted of a multigene family with about 50 copies in common wheat. Only a limited number of restriction fragments (approximately 15%) were used to determine the locations of members of this family on the long arm of group 1 chromosomes owing to the multiplicity of DNA bands. The variability of hybridized bands with the four genes was less in polyploids, but was more in the case of multigene families. RFLP analysis of polyploid wheats and their presumed ancestors was carried out with probes of the oat PhyA gene, the maize Ppc gene, the wheat RbcS gene and the wheat Lhcb1 (*)1 gene. The RFLP patterns of common wheat most closely resembled those of T. Dicoccum (Emmer wheat), T. urartu (A genome), Ae. speltoides (S genome) and Ae. squarrosa (D genome). Diversification of genes in the wheat complex appear to have occurred mainly at the diploid level. Based on RFLP patterns, B and S genomes were clustered into two major groups. The fragment numbers per genome were reduced in proportion to the increase of ploidy level for all four genes, suggesting that some mechanism(s) might operate to restrict, and so keep to a minimum, the gene numbers in the polyploid genomes. However, the RbcS genes, located on 2BS, were more conserved (double dosage), indicating that the above mechanism(s) does not operate equally on individual genes.

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Patulin is a mycotoxin mainly produced by Penicillium and Aspergillus. We investigated the incidence of patulin contamination in 179 samples of apple juice and 9 samples of mixed juice (containing apple juice concentrate as an ingredient) commercially available in the Tohoku district of Japan. Patulin was detected in 3 of 143 samples containing domestic fruits and in 6 of 45 samples containing imported products and products produced in Japan using imported apple juice concentrate. Patulin analyses were carried out using high-pressure liquid chromatography with a detection limit of 4 microg/liter. The patulin content of contaminated domestic samples (three samples with concentrations ranging from 6 to 10 microg/liter), imported samples (one sample with a concentration of 15 microg/liter), and domestic samples produced containing imported concentrate (five samples with concentrations ranging from 6 to 9 microg/liter) was lower than the maximum limit of 50 microg/liter currently adopted by many countries, including Japan.

Foxtail millet, common millet and Japanese barnyard millet have traditionally been important food sources in East Asian countries. Although waxy types of foxtail and common millet have been identified, a waxy mutant of the allohexaploid crop Japanese barnyard millet has not yet been reported. However, several Japanese landraces have been identified that have approximately half the level of amylose found in other varieties. We employed one of the low amylose landraces, 'Noge-Hie', to produce waxy Japanese barnyard millet using a c-radiation treatment. The seeds from a single M 2 plant stained red-brown with iodine solution, indicating the starch in the seeds lacked amylose. Colorimetric tests indicated that amylose was not present in endosperm tissue of the mutant, and analysis of starch granule bound proteins showed that waxy (Wx) protein was absent from the starch granules. The waxy trait was stably inherited in subsequent generations. Additionally, a PCR-based analysis demonstrated the presence of three separate waxy genes in the millet, and indicated that the low amylose landraces carry a deletion in one of these three genes.

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