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Svetlana Landjeva Viktor Korzun Ganka Ganeva 《Genetic Resources and Crop Evolution》2006,53(8):1605-1614
Simple sequence repeats (SSRs) were used to study the genetic diversity within old and modern Bulgarian winter wheat (Triticum aestivum L.) varieties released in 20th century. A set of 91 varieties were screened by 19 wheat microsatellite markers (WMS), covering
17 wheat chromosomes, and one secalin-specific marker for rye chromosome arm 1RS. A total of 136 allelic variants were detected
at 22 loci, ranging from 2 to 11, with an average of 6.8 alleles per marker. For 7 markers, null alleles were detected. The
occurrence of rare alleles (frequency <2%) was observed for 13 markers. The polymorphism information content (PIC) values
of the markers ranged from 0.10 (WMS0165 on 4AS) to 0.81 (WMS0437 on 7DL) with an average of 0.51. Approximately 74% of the
varieties, mostly non-commercial, showed heterogeneity, with an average level of 10.1%. For the majority of markers, the relative
frequencies of alleles varied considerably among different groups of varieties, revealing the effects of different selection
between breeding centres. Some alleles, present in old genotypes, were lost, and new alleles have been introduced into modern
varieties. Genetic diversity values over different periods of release were high, starting at 0.64 for varieties developed
before 1960 to reach 0.71 in 1990s, revealing no declining trends in the diversity due to breeding activity. The cluster analysis
discriminated all varieties (except for two) and revealed distinct groups of old and modern varieties, released from the main
breeding centres in Northern, Southern and Western Bulgaria. 相似文献
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The chromosome morphology and the variation in the N-band distribution along the chromosomes were studied in 13 accessions of the wild wheat Aegilops geniculata Roth (2n=28, genome formula UUM°M°). The karyotype consisted of four metacentric, five submetacentric, three subtelocentric, and two satellited pairs of chromosomes. The N-banding technique stained differentially all 14 chromosome pairs. The most prominent bands were observed near the centromeres and in the intercalary regions of both arms. Telomeric bands were found in only seven chromosomes. All chromosomes produced a specific banding pattern, permitting their identification. Polymorphism for presence or absence of particular bands was observed among the different accessions. The variable bands were located predominantly at the terminal and subterminal chromosome regions, and were also unevenly distributed over chromosomes. This polymorphism resulted in up to eight distinct banding pattern variants for each of the Ae. geniculata chromosomes. Each accession in this study showed a unique overall karyotype, sharing 0 to 8 chromosomes of identical banding pattern with the other accessions. A generalized idiogram of Aegilops geniculata is presented. 相似文献
3.
Natalia V. Melnikova Ganka D. Ganeva Zapryanka G. Popova Svetlana P. Landjeva Alexander M. Kudryavtsev 《Genetic Resources and Crop Evolution》2010,57(4):587-595
The polymorphism of gliadins was studied in 98 Bulgarian durum wheat (Triticum durum Desf.) landraces and classified according to the existing catalogues of blocks of gliadin components. In total, 31 alleles,
including 12 new ones, were revealed for five gliadin-coding loci. Nine allele families, which included several alleles coding
similar blocks differed only by minor components, were found. The gliadin loci had a high genetic diversity (H = 0.70), and Gli-A2
d
was the most polymorphic locus. Significant differences in allele distribution were observed through the Bulgarian region
under study. The results made it possible to explain the distribution by historical factors. Presumably, the genetic material
flew into the country via two different ways and different durum wheat subgroups contributed to the formation of Bulgarian
landraces. The landraces were a result of long-term selection and, probably, had a close association with the history of the
human populations of the region. 相似文献
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Ganka Ganeva Victor Korzun Svetlana Landjeva Zaprjanka Popova Nikolai K. Christov 《Genetic Resources and Crop Evolution》2010,57(2):273-285
The genetic diversity in a Triticum durum Desf. collection, consisting of 102 Bulgarian landraces, nine Bulgarian and 25 introduced cultivars was studied using 14
highly polymorphic microsatellite markers. A total of 100 alleles were identified, with an average of 7.14 alleles per marker.
The gene diversity values (He) of the markers for the total samples ranged from 0.23 (WMS357 and WMS631) to 0.77 (WMS46),
with an average of 0.52. Within the landraces that were collected from 18 sites in Southern Bulgaria showed 2–11 alleles per
locus with an average of 6.07. The microsatellite analysis suggests that the genetic diversity among landraces is lower compared
to the diversity levels for durum wheat in countries close to the main centers of wheat domestication. Breeding activities
have caused significant reduction of the allelic polymorphism, elimination of rare alleles, and increase in the number of
common alleles and the frequency of dominating alleles. 相似文献
5.
Ganka Chaneva Petya Parvanova Nikolina Tzvetkova Alexandra Uzunova 《Water, air, and soil pollution》2010,208(1-4):287-293
The effects of cadmium (Cd) and/or paraquat (PQ) toxicity on photosynthesis in maize leaves were examined by measurement of gas exchange and chlorophyll content in hydroponically cultured plants. It was found that growth rate was distinctly influenced only by 100 µM Cd treatment. Chlorophyll a and chlorophyll b decreased along with the increase of Cd concentration, while PQ spraying, alone and combined with Cd, increased chlorophyll a content on the third and seventh experimental days. Generally, carotenoid content increased in response to Cd and PQ and reached the highest levels at 100 µM Cd. Rate of photosynthesis in maize decreased after Cd treatment. CO2 assimilation was approximately 60% reduced at 50 µM Cd and 70% reduced in the presence of 100 µM Cd. PQ toxicity was partly overcome after the third day of exposure. Transpiration and stomatal conductance in maize leaves decreased on the third day along with Cd concentration and PQ spraying, except for the 25-µM Cd-treated plants. On the tenth day, the 25-µM Cd-treated plants and those from PQ-treated variants showed an increase of transpiration and stomatal conductance. Maize exhibited an ability to accumulate Cd in high quantities, especially in the roots—over 4,500 mg Cd/kg dry weight. 相似文献
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7.
Ganka?GanevaEmail author Viktor?Korzun Svetlana?Landjeva Nikolaj?Tsenov Mariana?Atanasova 《Euphytica》2005,145(3):305-315
Bulgarian common wheat cultivars released in the period 1925–2003 were studied using the gibberellic acid (GA) test and microsatellite
analysis of the Xgwm261 locus on chromosome 2DS to identify the semi-dwarfing (Rht) genes. The old cultivars, isolated through selection from landraces, carried rare alleles (211- and 215-bp) at Xgwm261 locus, and those developed by hybridisation to foreign cultivars, carried the 165- and 174-bp alleles. Forty-two (55.3%)
of 76 modern cultivars were GA-responsive. The 192-bp allele, diagnostic for Rht8, was observed in 64 (84.2%) modern cultivars, of which 37 carry Rht8 alone, and 27 possess a combination of Rht8 and a GA-insensitive allele viz. Rht-B1d (17); Rht-D1b (6) and Rht-B1b (4). The 174-bp allele is present in seven cultivars, only one of which is photoperiod-sensitive, and the rest are day-length
insensitive. The 203-bp allele was found in six modern cultivars. Cultivars carrying the Rht8 allele are the most widespread and some of them have been cultivated for a long period. Cultivars with the `Saitama 27' allele
(Rht-B1d) are the most productive and are second in distribution in the country. The recently observed trend for increasing the proportion
of cultivars with GA-insensitive Rht genes is probably due to their combination with the 192-bp allele of Xgwm261 locus tightly linked to the Ppd-D1, to the break of the link between the 174-bp allele and ppd-D1, and to the introduction of other genes influencing flowering time. 相似文献
8.
Obesity and metabolic syndrome in circadian Clock mutant mice 总被引：2，自引：0，他引：2
Turek FW Joshu C Kohsaka A Lin E Ivanova G McDearmon E Laposky A Losee-Olson S Easton A Jensen DR Eckel RH Takahashi JS Bass J 《Science (New York, N.Y.)》2005,308(5724):1043-1045
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