A set of 24 microsatellite markers was used for assessing the genetic diversity of 40 obsolete and modern Bulgarian winter wheat (Triticum aestivum L.) varieties. The total number of alleles detected was 215 with the average per locus 8.96 and varying from 4 (Xgwm480, Xgwm333) to 15 (Xgwm291). The obsolete varieties of interest were created in the period between 1911 and 1938 through selection of local populations, originating from three Bulgarian regions. The number of alleles detected in those old varieties was 182 with an average of 7.58, out of which 2.67 were rare. Regional differences in the allelic richness and diversity were also observed. Greater number of alleles was found in the old varieties, originating from South Bulgarian and Northeast landraces. Modern wheat breeding in Bulgaria has led to a decrease in the alleles per locus ratio and an increase in the allelic frequency. The same process has invalidated 44.2% of the old wheat alleles, preserved 40.9% and made possible an inflow of 14.9% new alleles. The artificial selection tolerated the preservation of a big number of the alleles of some loci found in old varieties (Xgwm205 and Xgwm160), while others experienced loss of alleles (Xgwm291, Xgwm312, Xgwm219 and Xgwm261). The genealogical analysis of 94 Bulgarian varieties, created in the period 1940-2000, showed that 27.7% of those varieties were based on Bulgarian landraces.
In order to investigate the origin of two 4B-5R wheat-rye translocations a number of microsatellite markers were considered, (a) which were specific for the rye chromosome arm 5RL and (b) which should enable precise characterisation for the gene pool of a ‘Cornell’ wheat derivative. Seven out of eight markers revealed amplification fragments with the rye control, while the marker WMS0186 amplified only a PCR product with the appropriate chromosome arm of the wheat control. The heterogeneity of the DNA fragment patterns among five wheat-rye translocation lines confirms different wheat backgrounds of the American, Danish/UK, Hungarian, and Swedish sources of the 4B-5R translocations. The homogeneous DNA marker patterns of ‘Viking-hairy neck’ and ‘Cornell Sel. 82a1-2-4-7’ are particularly clear. The corresponding molecular markers together with the cytological data, genomic
hybridisation, the physiological investigations, and the historical review support the hypothesis of a common origin of ‘Viking-hairy neck’ and ‘Cornell Sel. 82a1-2-4-7’. The importance of the results for practical breeding and for introgression experiments is discussed.
PCR assays specific for the GA insensitive dwarfing genes (alleles)
were employed to study a series of additional alleles of
. The amplification profiles of
were not distinguishable from one another, whereas lines carrying
amplified a product analogous to that of the wild type. At the 4D locus, no discrimination was possible between
. As a result, the utilisation of these PCR assays is limited. Examples of the analysis of germplasm and spontaneous occurring off-types are presented.
Genetic diversity was investigated in a set of eleven hexaploid wheat genotypes originated from CIMMYT, Turkey in comparison with some modern European mostly originated from KWS wheat breeding program using 24 wheat SNP markers. The lowest and highest genetic dissimilarities were observed between genotypes Opus and LDO 330/06, KWS Salix and LDO 330/06, respectively. Based on cluster analysis, 38 wheat genotypes were grouped in two main clusters. Although the grouping pattern is very origin heterogeneous in each group, the grouping pattern of some genotypes appeared to be associated, to some extent. Principal coordinate analysis (PCoA) was used as an alternative way of visualizing the genotypic data. The first, second and third principal components explained 17.79%, 14.39% and 12.24% of the variation, respectively. This study can also be an indicator for breeders to evolve genotypes with diverse genetic background to achieve sustainability in wheat production, to get favorable heterotic combinations in a wheat improvement program.
Authors:C. Knopf, H. Becker, E. Ebmeyer, and V. Korzun
Ninety percent of wheat varieties grown worldwide have a semi-dwarf phenotype controlled by three major genes
. The objective of this study was to determine their frequency in modern wheat varieties grown in Germany. Ninety-five winter wheat varieties that were registered in Germany in 2004 were screened with PCR-based markers for
and with the microsatellite WMS261 for
allele for plant height reduction was not found in any of the varieties, which confirms previous studies.
alleles were present in 44% of the screened varieties, but only 6% contained
, which predominates in northern Europe.
was found in 38% of the varieties, which were planted on 34% of the total area of wheat in Germany. Wheat varieties with
were shorter and higher yielding than wheat varieties without this allele, but more susceptible to
head blight, which could limit their productivity.
Authors:K. Shiraishi, Y. Muramatsu, I. Los, V. Korzun, N. Tsigankov, and P. Zamostyan
Total diet samples for Ukrainians and Japanese were collected by duplicate portion studies in relation to the Chernobyl accident.
Stable iodine and bromine in the diet samples were determined by using ICP-MS after chemical separation. Daily intakes of
iodine for Ukrainians and Japanese were found to be 110±104 and 1770±1610 μg per person per day, respectively. Daily intakes
of Br were as follows: Ukrainians 3.47±2.12 mg; Japanese 11.4±2.4 mg. Daily iodine intake in Ukrainians was lower than the
recommended dietary allowance (150 μg) and showed the relationship of high prevalence of goiter in this area.
Authors:K. Shiraishi, S. Ko, T. Ban-nai, H. Arae, K. Ayama, P. Zamostyan, N. Tsigankov, I. Los, and V. Korzun
Daily intakes of 134Cs and 137Cs in Ukrainians were estimated in relation to the health effects on habitants after the Chernobyl accident. Two hundred and
sixty-eight diet samples were collected from 25 oblasts (regions) using a duplicate portion method. For Ukrainians, the range
and median daily intakes of 137Cs were 0.53–571 and 8.8 Bq per person, respectively. Intakes of 134Cs were also detected in highly 137Cs contaminated areas. Daily intakes of 134Cs were in the range of not detected to 3.6 Bq per person. Using the highest radiocesium intakes, annual effective doses for
134Cs and 137Cs were estimated to be 2.5·10−2 and 2.7 mSv, respectively.
Authors:S. Ko, K. Shiraishi, S. K. Sahoo, K. Ayama, Y. Muramatsu, I. P. Los, V. N. Korzun, N. Y. Tsigankov, and P. V. Zamostyan
The concentration of stable iodine and bromine in Ukrainian milk has been determined in relation to the effect of the Chernobyl
nuclear power plant accident. The geometric mean of iodine and bromine concentration was 31.0mg/kg and 2.57 mg/kg, respectively.
Compared with Japanese milk, it was statistically lower. Bromine concentrations in Ukrainian and Japanese milk were not significantly
different. Contribution of milk to daily intake of iodine and bromine in Ukrainian adults has been estimated to 88% and 94%.