The Acıgöl Graben in SW Turkey,ca.50-55 km in length and 11-15 km in width,formed during the Miocene to Quaternary periods.This graben is bounded by active normal faults of MaymundağıFault(MF)to the northwest and...The Acıgöl Graben in SW Turkey,ca.50-55 km in length and 11-15 km in width,formed during the Miocene to Quaternary periods.This graben is bounded by active normal faults of MaymundağıFault(MF)to the northwest and the GemişFault Zone(GFZ)to the southeast that have triggered significant earthquakes,causing considerable damage.This study focuses on the Bozkurt segment of the MF,which caused a damaging earthquake(Mw 6.0)in 2019 and another significant earthquake in 1886 during historical times.A paleoseismological trench survey along the Bozkurt segment revealed at least two faulting events,with the last event producing a vertical displacement of 0.25 m.The Optical Stimulated Luminescence(OSL)dating indicates that the last earthquake occurred 3.13±0.33 ka BP,while the penultimate earthquake occurred 4.0±0.72 ka BP.These dates correspond to a long-term slip rate of approximately 0.36±0.11 mm/a and a mean recurrence interval of 2.08 ka,short-term slip rate 0.78±0.16 mm/a and recurrence interval of 0.96 ka,and compatible with the mean sedimentation rate of 0.26 mm/a,calculated from drill logs in Acıgöl basin-fill.Considering the 6 km length of the Bozkurt segment and its vertical displacement of 0.25 m in the last event,this segment has the potential to generate earthquakes ranging from 5.6 to 5.9 Mw.Long-term slip rates derived from geomorphological data are 0.56 mm/year to the north and 0.64 mm/a to the south of the graben,indicating higher subsidence on the southern margin.These rates are in accordance with the slip rates calculated from the paleoseismological trench survey and sedimentation rate from the drill-log.These indications show that the Bozkurt segment is an active Holocene fault with relatively long recurrence intervals and low-slip rate.Consequently,the paleoseismological studies in combination with geomorphological data are important tool to assess seismic hazards and to define the characteristics of individual fault segments.展开更多
Background: Gossypium arboreum is a diploid species cultivated in the Old World. It possesses favorable characters that are valuable for developing superior cotton cultivars.Method: A set of 197 Gossypium arboreum acc...Background: Gossypium arboreum is a diploid species cultivated in the Old World. It possesses favorable characters that are valuable for developing superior cotton cultivars.Method: A set of 197 Gossypium arboreum accessions were genotyped using 80 genome-wide SSR markers to establish patterns of the genetic diversity and population structure. These accessions were collected from three major G. arboreum growing areas in China. A total of 255 alleles across 80 markers were identified in the genetic diversity analysis.Results: Three subgroups were found using the population structure analysis, corresponding to the Yangtze River Valley, North China, and Southwest China zones of G.arboreum growing areas in China. Average genetic distance and Polymorphic information content value of G. arboreum population were 0.34 and 0.47, respectively, indicating high genetic diversity in the G. arboreum germplasm pool. The Phylogenetic analysis results concurred with the subgroups identified by Structure analysis with a few exceptions. Variations among and within three groups were observed to be 13.61% and 86.39%, respectively.Conclusion: The information regarding genetic diversity and population structure from this study is useful for genetic and genomic analysis and systematic utilization of economically important traits in G. arboreum.展开更多
Gossypium arboreum (2n = 26, A2) is a diploid species with limited production in acreage com-pared with G. hirsutum and G. barbadense. However, its unique traits such as insect and disease resistance contribute an imp...Gossypium arboreum (2n = 26, A2) is a diploid species with limited production in acreage com-pared with G. hirsutum and G. barbadense. However, its unique traits such as insect and disease resistance contribute an important germplasm to cotton breeding. So polyploid manipulation for G. arboreum is an effective approach of germplasm development. This research focused on tetraploid induction of G. arboreum by colchicine. Morphology and cytology identifications for obtained mutants were also conducted. The seedling growth and development of all mutants was more stunted than controls. According to preliminary morphological characteristics, mutant rates in different treatment were statistically estimated and the highest mutant rate was 42.31% under the treatment of 0.1% colchicine for 24 hours. The chromosome number of most mutants was 2n = 4x = 52, while the chromosome number of diploid controls was 2n = 2x = 26 by cytology observation of root tip cells. By microscope observation of low leaf epidermis, there were significant differences for stoma area between tetraploids and diploids. The meiosis behavior of the induced tetraploid was much more complex than that of the diploid. At diakinesis, some univalent, trivalent and polyvalent were also observed besides bivalent and quadrivalent. There were different kinds of polyad in tetraspore period of mutants. The dissociate chromosomes existed during metaphase I and II, the unbalance separation of chromosomes existed during anaphase I and II. As a result, tetraploid mutants of G. arboreum were identified and their desirable traits would be further evaluated to incorporate into next breeding program.展开更多
Plants have developed a complicated defense mechanism during evolution to resist the harmful pathogens they encountered.The mechanism involves the interaction of the plant resistance(R)
文摘The Acıgöl Graben in SW Turkey,ca.50-55 km in length and 11-15 km in width,formed during the Miocene to Quaternary periods.This graben is bounded by active normal faults of MaymundağıFault(MF)to the northwest and the GemişFault Zone(GFZ)to the southeast that have triggered significant earthquakes,causing considerable damage.This study focuses on the Bozkurt segment of the MF,which caused a damaging earthquake(Mw 6.0)in 2019 and another significant earthquake in 1886 during historical times.A paleoseismological trench survey along the Bozkurt segment revealed at least two faulting events,with the last event producing a vertical displacement of 0.25 m.The Optical Stimulated Luminescence(OSL)dating indicates that the last earthquake occurred 3.13±0.33 ka BP,while the penultimate earthquake occurred 4.0±0.72 ka BP.These dates correspond to a long-term slip rate of approximately 0.36±0.11 mm/a and a mean recurrence interval of 2.08 ka,short-term slip rate 0.78±0.16 mm/a and recurrence interval of 0.96 ka,and compatible with the mean sedimentation rate of 0.26 mm/a,calculated from drill logs in Acıgöl basin-fill.Considering the 6 km length of the Bozkurt segment and its vertical displacement of 0.25 m in the last event,this segment has the potential to generate earthquakes ranging from 5.6 to 5.9 Mw.Long-term slip rates derived from geomorphological data are 0.56 mm/year to the north and 0.64 mm/a to the south of the graben,indicating higher subsidence on the southern margin.These rates are in accordance with the slip rates calculated from the paleoseismological trench survey and sedimentation rate from the drill-log.These indications show that the Bozkurt segment is an active Holocene fault with relatively long recurrence intervals and low-slip rate.Consequently,the paleoseismological studies in combination with geomorphological data are important tool to assess seismic hazards and to define the characteristics of individual fault segments.
基金supported by the National Natural Science Foundation of China Agriculture(Grant No.2015NWB039)
文摘Background: Gossypium arboreum is a diploid species cultivated in the Old World. It possesses favorable characters that are valuable for developing superior cotton cultivars.Method: A set of 197 Gossypium arboreum accessions were genotyped using 80 genome-wide SSR markers to establish patterns of the genetic diversity and population structure. These accessions were collected from three major G. arboreum growing areas in China. A total of 255 alleles across 80 markers were identified in the genetic diversity analysis.Results: Three subgroups were found using the population structure analysis, corresponding to the Yangtze River Valley, North China, and Southwest China zones of G.arboreum growing areas in China. Average genetic distance and Polymorphic information content value of G. arboreum population were 0.34 and 0.47, respectively, indicating high genetic diversity in the G. arboreum germplasm pool. The Phylogenetic analysis results concurred with the subgroups identified by Structure analysis with a few exceptions. Variations among and within three groups were observed to be 13.61% and 86.39%, respectively.Conclusion: The information regarding genetic diversity and population structure from this study is useful for genetic and genomic analysis and systematic utilization of economically important traits in G. arboreum.
文摘Gossypium arboreum (2n = 26, A2) is a diploid species with limited production in acreage com-pared with G. hirsutum and G. barbadense. However, its unique traits such as insect and disease resistance contribute an important germplasm to cotton breeding. So polyploid manipulation for G. arboreum is an effective approach of germplasm development. This research focused on tetraploid induction of G. arboreum by colchicine. Morphology and cytology identifications for obtained mutants were also conducted. The seedling growth and development of all mutants was more stunted than controls. According to preliminary morphological characteristics, mutant rates in different treatment were statistically estimated and the highest mutant rate was 42.31% under the treatment of 0.1% colchicine for 24 hours. The chromosome number of most mutants was 2n = 4x = 52, while the chromosome number of diploid controls was 2n = 2x = 26 by cytology observation of root tip cells. By microscope observation of low leaf epidermis, there were significant differences for stoma area between tetraploids and diploids. The meiosis behavior of the induced tetraploid was much more complex than that of the diploid. At diakinesis, some univalent, trivalent and polyvalent were also observed besides bivalent and quadrivalent. There were different kinds of polyad in tetraspore period of mutants. The dissociate chromosomes existed during metaphase I and II, the unbalance separation of chromosomes existed during anaphase I and II. As a result, tetraploid mutants of G. arboreum were identified and their desirable traits would be further evaluated to incorporate into next breeding program.
文摘Plants have developed a complicated defense mechanism during evolution to resist the harmful pathogens they encountered.The mechanism involves the interaction of the plant resistance(R)
