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1.
The prehistoric salt mine of Hallstatt together with its burial ground is one of the most prominent archaeological sites in the world, and has given its name to the “Hallstatt period”, an epoch of European prehistory (800 to 400 BCE). Due to the perfect conservation in rock salt a high number of organic materials have been found, including mostly wooden artefacts and structural timber.More than 2000 samples were taken from various archaeological sites in the mines as well as at the surface. It was possible to date 763 samples by the means of dendrochronology and by 14C wiggle matching. The dendrochronological dating was possible due to crossdating with various available chronologies (like Villingen-Magdalenenberg or Dachstein/Schwarzer See). The fir (Abies alba Mill.) chronologies span the periods: -1232 to -1063; -819 to -425 and -371 to-129. The spruce (Picea abies L. Karst.) chronologies span the periods: -1228 to -1063; -813 to -669 and -342 to -123. The larch (Larix decidua Mill.) chronologies span the periods: -1393 ± 18 to-1286 ± 18 based on wiggle matching data and -252 to -164. A beech (Fagus sylvatica L.) chronology span the time -1182 to -1062. 相似文献
2.
Though the extraction of increment cores is common practice in tree-ring research, there is no standard for the number of samples per tree, or trees per site needed to accurately describe the common growth pattern of a discrete population of trees over space and time. Tree-ring chronologies composed of living, subfossil and archaeological material often combine an uneven distribution of increment cores and disc samples. The effects of taking one or two cores per tree, or even the inclusion of multiple radii measurements from entire discs, on chronology development and quality remain unreported. Here, we present four new larch (Larix cajanderi Mayr) ring width chronologies from the same 20 trees in northeastern Siberia that have been independently developed using different combinations of core and disc samples. Our experiment reveals: i) sawing is much faster than coring, with the latter not always hitting the pith; ii) the disc-based chronology contains fewer locally absent rings, extends further back in time and exhibits more growth coherency; iii) although the sampling design has little impact on the overall chronology behaviour, lower frequency information is more robustly obtained from the disc measurements that also tend to reflect a slightly stronger temperature signal. In quantifying the influence of sampling strategy on the quality of tree-ring width chronologies, and their suitability for climate reconstructions, this study provides useful insights for optimizing fieldwork campaigns, as well as for developing composite chronologies from different wood sources. 相似文献
3.
A prerequisite for successful dating of wooden archaeological finds and historic wooden constructions in a specific territory is the existence of a chronology. In the Czech Republic the species most frequently dated by dendrochronology is oak (Quercus spp.). There are two territories where oak forests can be found (Bohemia and Moravia/Silesia), which are divided by an area without oak – the Highlands (Vyso?ina). The previous oak chronology for the Czech Republic from 2005 was extended in 2010, and currently we have a discontinuous oak chronology (CZGES 2010) ranging from 4682 bc to 2006 ad with a large sample size between 760 ad and the present. When comparing this chronology with European chronologies, the highest degree of similarity has been observed with chronologies for Eastern Austria, most of Germany and the Polish part of South Silesia. When comparing the chronologies for Moravia/Silesia (MORGES 2010) and Bohemia (CECHGES 2010) separately with chronologies from the Pannonian Basin, the Moravian/Silesian chronology manifests higher degrees of similarity. The Czech oak chronology enlarges the European network of chronologies, which is necessary for dendroarchaeological applications mainly. 相似文献
4.
Ernst van der Maaten Marieke van der Maaten-Theunissen Allan Buras Tobias Scharnweber Sonia Simard Knut Kaiser Sebastian Lorenz Martin Wilmking 《PloS one》2015,10(8)
In this study, we explore the potential to reconstruct lake-level (and groundwater) fluctuations from tree-ring chronologies of black alder (Alnus glutinosa L.) for three study lakes in the Mecklenburg Lake District, northeastern Germany. As gauging records for lakes in this region are generally short, long-term reconstructions of lake-level fluctuations could provide valuable information on past hydrological conditions, which, in turn, are useful to assess dynamics of climate and landscape evolution. We selected black alder as our study species as alder typically thrives as riparian vegetation along lakeshores. For the study lakes, we tested whether a regional signal in lake-level fluctuations and in the growth of alder exists that could be used for long-term regional hydrological reconstructions, but found that local (i.e. site-specific) signals in lake level and tree-ring chronologies prevailed. Hence, we built lake/groundwater-level reconstruction models for the three study lakes individually. Two sets of models were considered based on (1) local tree-ring series of black alder, and (2) site-specific Standardized Precipitation Evapotranspiration Indices (SPEI). Although the SPEI-based models performed statistically well, we critically reflect on the reliability of these reconstructions, as SPEI cannot account for human influence. Tree-ring based reconstruction models, on the other hand, performed poor. Combined, our results suggest that, for our study area, long-term regional reconstructions of lake-level fluctuations that consider both recent and ancient (e.g., archaeological) wood of black alder seem extremely challenging, if not impossible. 相似文献
5.
The Regional Curve Standardization (RCS) is one of the most employed standardization methods to remove biological signals in long tree ring chronologies. The approach assumes that an overall age-related growth trend typify all tree ring series to be included in a standardized tree ring chronology. Although several potential problems of the method have been examined, the influence of varying the sampling height along tree stems has not been evaluated. Considering that age-related growth trends may vary with stem height, biases may arise when combining samples from unknown or variable sampling heights, a frequent situation with subfossil logs. In this study we perform a detailed stem analysis of 15 lakeshore black spruce (Picea mariana Mill. B.S.P.) trees in the taiga of eastern Canada to describe how the age-related growth trend varies with stem height and evaluate associated biases in RCS chronologies built from living and subfossil trees. Results show that the age-related growth trends vary markedly and systematically along stems, potentially generating large methodological biases in RCS chronologies, especially near the recent chronology end. These biases may lead to erroneous reconstructions of recent climatic trends and cause false divergence between tree ring and climate series. We have developed a correction procedure that appears efficient in removing these biases from chronologies built with the lakeshore trees and associated subfossil logs. 相似文献
6.
Kristof Haneca Ilse Boeren Joris Van Acker Hans Beeckman 《Vegetation History and Archaeobotany》2006,15(2):137-144
Throughout the Middle Ages forests in Flanders (northern Belgium) experienced a dramatic human influence. Forests were logged
for wood supply and converted to arable land. The structure of the remaining forests was altered. This, combined with the
tempering influence of the Atlantic climate, results in conditions that are suboptimal for dendrochronological research. Tree-ring
series of Quercus robur and Q. petraea of timber from medieval archaeological sites are often short, show abrupt growth-rate variations and are complacent. The
question arises whether tree-ring series of this type are potential records of past management and whether they could constitute
the basis of a reference chronology for archaeological dating. During six archaeological excavations in and around the medieval
town of Ypres, cross-sections were collected. The tree-ring series could be dated back to the 12th–14th centuries, using reference
chronologies from surrounding regions. The growth pattern of the short sequences displays a high similarity to tree-ring series
from modern coppice. For the first time, it has been confirmed that dendrochronological analysis in Flanders is possible and
can provide valuable information on medieval forest use and structure. 相似文献
7.
Although the importance of centuries-long tree ring width oak chronologies in dating wood, eastern European regions are still lacking a reference chronology. To fill this geographical gap, we combined living and historical chronologies from the Moldova region, including part of Romania and the Republic of Moldova. Here we present the “Suceava oak chronology” as the first 804 years long chronology continuously covering the 1216–2019 period. Our analyses further revealed the strong teleconnection of the Suceava oak chronology with south European ones. The link between Romania and northern Turkey chronologies is of particular importance in the context of the high abundance of undated subfossil and archaeological/historical oak wood in eastern Europe and intense wood trades with central Europe in XV-XVII centuries. The availability of the Suceava oak chronology will provide a good base for precise dating and climatic reconstructions. 相似文献
8.
Nesibe Köse Ünal Akkemik H. Tuncay Güner H. Nüzhet Dalfes Henri D. Grissino-Mayer M. Sinan Özeren Tayfun Kındap 《International journal of biometeorology》2013,57(5):691-701
We developed a high quality reconstruction of May–June precipitation for the interior region of southwestern Turkey using regional tree-ring data calibrated with meteorological data from Burdur. In this study, three new climate sensitive black pine chronologies were built. In addition to new chronologies, four previously published black pine chronologies were used for the reconstruction. Two separate reconstructions were developed. The first reconstruction used all site chronologies over the common interval AD 1813–2004. The second reconstruction used four of the chronologies with a common interval AD 1692–2004. R 2 values of the reconstructions were 0.64 and 0.51 with RE values of 0.63 and 0.51, respectively. During the period AD 1692–1938, 41 dry and 48 wet events were found. Very dry years occurred in AD 1725, 1814, 1851, 1887, 1916, and 1923, while very wet years occurred in AD 1736, 1780, 1788, 1803, and 1892. The longest dry period was 16 years long between 1860 and 1875. We then explored relationships between the reconstructed rainfall patterns and major volcanic eruptions, and discovered that wetter than normal years occurred during or immediately after the years with the largest volcanic eruptions. 相似文献
9.
The black locust (Robinia pseudoacacia Linn.) is the dominant tree species in the “grain for green” project on the Loess Plateau (LP) of China, and brings many ecological benefits to this planted region. However, there are concerns regarding its suitability as a plantation forest species in different regions of the LP. We used a dendroclimatological approach to investigate the radial growth response of black locust to varying climate in two sites on the LP with differing precipitation gradients. We took tree-ring samples from black locust in Yongshou County (in the semi-humid southern LP) and Shenmu County (in the semi-arid northern LP), and developed tree-ring width (TRW) chronologies for each. We performed moving correlation analyses between TRW chronologies and aggregated thermal (maximum temperature (TMX), minimum temperature (TMN), mean temperature (TMP)) and hydroclimatic factors (precipitation, self-calibrated Drought Severity Index (scPDSI), and humidity). The results demonstrated the increased influence of thermal factors during autumn, and the generally decreased influence of hydroclimatic factors on black locust radial growth in Yongshou, compared with the decreasing influence of thermal factors (during all seasons) and increasing influence of hydroclimatic factors (precipitation during summer, scPDSI and humidity during autumn) on black locust radial growth in Shenmu. The results indicated that black locust radial growth might benefit from the current climatic conditions in the southern LP. However, black locust radial growth stressed by water availability in the northern LP, which may reduce its vitality and productivity as climate warms in the future. These results have implications for regional forestry planning and ecological restoration strategies on the LP. 相似文献
10.
Thomas Giesecke Basil Davis Simon Brewer Walter Finsinger Steffen Wolters Maarten Blaauw Jacques-Louis de Beaulieu Heather Binney Ralph M. Fyfe Marie-José Gaillard Graciela Gil-Romera W. O. van der Knaap Petr Kuneš Norbert Kühl Jacqueline F. N. van Leeuwen Michelle Leydet André F. Lotter Elena Ortu Malte Semmler Richard H. W. Bradshaw 《Vegetation History and Archaeobotany》2014,23(1):75-86
The number of well-dated pollen diagrams in Europe has increased considerably over the last 30 years and many of them have been submitted to the European Pollen Database (EPD). This allows for the construction of increasingly precise maps of Holocene vegetation change across the continent. Chronological information in the EPD has been expressed in uncalibrated radiocarbon years, and most chronologies to date are based on this time scale. Here we present new chronologies for most of the datasets stored in the EPD based on calibrated radiocarbon years. Age information associated with pollen diagrams is often derived from the pollen stratigraphy itself or from other sedimentological information. We reviewed these chronological tie points and assigned uncertainties to them. The steps taken to generate the new chronologies are described and the rationale for a new classification system for age uncertainties is introduced. The resulting chronologies are fit for most continental-scale questions. They may not provide the best age model for particular sites, but may be viewed as general purpose chronologies. Taxonomic particularities of the data stored in the EPD are explained. An example is given of how the database can be queried to select samples with appropriate age control as well as the suitable taxonomic level to answer a specific research question. 相似文献
11.
Martina Demuro Lee J. Arnold Josep M. Parés Alfredo Pérez-González Ana I. Ortega Juan L. Arsuaga José M. Bermúdez de Castro Eudald Carbonell 《PloS one》2014,9(10)
The archaeological karstic infill site of Galería Complex, located within the Atapuerca system (Spain), has produced a large faunal and archaeological record (Homo sp. aff. heidelbergensis fossils and Mode II lithic artefacts) belonging to the Middle Pleistocene. Extended-range luminescence dating techniques, namely post-infrared infrared stimulated luminescence (pIR-IR) dating of K-feldspars and thermally transferred optically stimulated luminescence (TT-OSL) dating of individual quartz grains, were applied to fossil-bearing sediments at Galería. The luminescence dating results are in good agreement with published chronologies derived using alternative radiometric dating methods (i.e., ESR and U-series dating of bracketing speleothems and combined ESR/U-series dating of herbivore teeth), as well as biochronology and palaeoenvironmental reconstructions inferred from proxy records (e.g., pollen data). For the majority of samples dated, however, the new luminescence ages are significantly (∼50%) younger than previously published polymineral thermoluminescence (TL) chronologies, suggesting that the latter may have overestimated the true burial age of the Galería deposits. The luminescence ages obtained indicate that the top of the basal sterile sands (GIb) at Galería have an age of up to ∼370 thousand years (ka), while the lowermost sub-unit containing Mode II Acheulean lithics (base of unit GIIa) was deposited during MIS 9 (mean age = 313±14 ka; n = 4). The overlying units GIIb-GIV, which contain the richest archaeopalaeontological remains, were deposited during late MIS 8 or early MIS 7 (∼240 ka). Galería Complex may be correlative with other Middle Pleistocene sites from Atapuerca, such as Gran Dolina level TD10 and unit TE19 from Sima del Elefante, but the lowermost archaeological horizons are ∼100 ka younger than the hominin-bearing clay breccias at the Sima de los Huesos site. Our results suggest that both pIR-IR and single-grain TT-OSL dating are suitable for resolving Middle Pleistocene chronologies for the Sierra de Atapuerca karstic infill sequences. 相似文献
12.
Gliganic LA Jacobs Z Roberts RG Domínguez-Rodrigo M Mabulla AZ 《Journal of human evolution》2012,62(4):533-547
The archaeological deposits at Mumba rockshelter, northern Tanzania, have been excavated for more than 70 years, starting with Margit and Ludwig Köhl-Larsen in the 1930s. The assemblages of Middle Stone Age (MSA) and Later Stone Age (LSA) artefacts collected from this site constitute the type sequences for these cultural phases in East Africa. Despite its archaeological importance, however, the chronology of the site is poorly constrained, despite the application since the 1980s of several dating methods (radiocarbon, uranium-series and amino acid racemisation) to a variety of materials recovered from the deposits. Here, we review these previous chronologies for Mumba and report new ages obtained from optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL) measurements on single grains of quartz and multi-grain aliquots of potassium (K) feldspar from the MSA and LSA deposits. Measurements of single grains of quartz allowed the rejection of unrepresentative grains and the application of appropriate statistical models to obtain the most reliable age estimates, while measurements of K-feldspars allowed the chronology to be extended to older deposits. The seven quartz ages and four K-feldspar ages provide improved temporal constraints on the archaeological sequence at Mumba. The deposits associated with the latest Kisele Industry (Bed VI-A) and the earliest Mumba Industry (Bed V) are dated to 63.4 ± 5.7 and 56.9 ± 4.8 ka (thousands of years ago), respectively, thus constraining the time of transition between these two archaeological phases to ∼60 ka. An age of 49.1 ± 4.3 ka has been obtained for the latest deposits associated with the Mumba Industry, which show no evidence for post-depositional mixing and contain ostrich eggshell (OES) beads and abundant microlithics. The Nasera Industry deposits (Bed III) contain large quantities of OES beads and date to 36.8 ± 3.4 ka. We compare the luminescence ages with the previous chronologies for Mumba, and briefly discuss how the revised chronology fits in the context of existing archaeological records and palaeoclimatic reconstructions for East Africa. 相似文献
13.
《PloS one》2014,9(7)
The first arrivals of hominin populations into Eurasia during the Early Pleistocene are currently considered to have occurred as short and poorly dated biological dispersions. Questions as to the tempo and mode of these early prehistoric settlements have given rise to debates concerning the taxonomic significance of the lithic assemblages, as trace fossils, and the geographical distribution of the technological traditions found in the Lower Palaeolithic record. Here, we report on the Barranc de la Boella site which has yielded a lithic assemblage dating to ∼1 million years ago that includes large cutting tools (LCT). We argue that distinct technological traditions coexisted in the Iberian archaeological repertoires of the late Early Pleistocene age in a similar way to the earliest sub-Saharan African artefact assemblages. These differences between stone tool assemblages may be attributed to the different chronologies of hominin dispersal events. The archaeological record of Barranc de la Boella completes the geographical distribution of LCT assemblages across southern Eurasia during the EMPT (Early-Middle Pleistocene Transition, circa 942 to 641 kyr). Up to now, chronology of the earliest European LCT assemblages is based on the abundant Palaeolithic record found in terrace river sequences which have been dated to the end of the EMPT and later. However, the findings at Barranc de la Boella suggest that early LCT lithic assemblages appeared in the SW of Europe during earlier hominin dispersal episodes before the definitive colonization of temperate Eurasia took place. 相似文献
14.
Results of the tree-ring dating of samples from the three Russian settlements of the 18th century (Bjornbeinflyene, Palffyodden, and Schonningholmane) at Svalbard are presented. The present study is a development of a previous work (Chochorowski and Krapiec, 2017). These stations were discovered during excavations conducted by the Polish archaeological expedition of Jagiellonian University in the Sorkappland and Hornsund fjord regions of the Svalbard Archipelago. In total, 5 non-dated samples of the previous work were reanalyzed for these sites: Bjornbeinflyene (2 samples), Palffyodden (1 sample), Schonningholmane (1 sample) and relics from the landing site on the Torrflya coast (1 sample). All samples from these settlements are constructional elements of dwellings, appearing to be prefabricates brought from the continent, and only one of them is a driftwood timber. These floating chronologies were cross-dated against more than 200 master tree-ring chronologies from the Arctic coast, including as well our own data. Cross-dating was performed by CORINA software which includes t-values calculated with different detrending options. As a result, it was possible to successfully date and determine the place of origin of these samples. Results obtained do not contradict the data of radiocarbon and archaeological dating and indicate the possible use of wood from the territories of the White and Kara Sea basins as a building material for the Russian Pomor settlements in Svalbard. 相似文献
15.
This paper describes attempts to develop tree-ring chronologies from New Zealand matai (Prumnopitys taxifolia) and miro (Prumnopitys ferruginea). These tree species have been recovered from Māori archaeological contexts, including as objects such as canoes and palisade posts. Dendrochronology offers the potential to establish accurate and precise calendar dates for wooden objects but relies on cultural use of species that are also suitable for tree-ring analysis, and the availability of calendar-dated reference chronologies for crossdating wood of unknown age. We used archived cross-section and core samples from seven sites in central North Island, and nineteen core samples collected in 2019 from matai and miro trees at Pureora Forest Park for our analysis. Some of these samples came from long lived trees, with ring counts indicating ages up to 800 years old. We found that both matai and miro exhibit considerable variability in ring clarity and ring width. They also have ring anomalies affecting the reliability of ring-width series. Miro was very challenging, and no tree sequences were built for this species. Tree-ring sequences were built for several matai samples but no secure inter-tree matches were identified. Further analysis of matai samples is required to establish reliable tree ring patterns for inter-tree and inter-site crossmatching. 相似文献
16.
In the past decade, striking advances have been made in the field of gene introducing/disrupting technology including generation of transgenic and knockout mice, which have enabled us to elucidate roles of specific genes in development. In this technology, embryos introduced with exogenous genes or chimeric embryos aggregated/injected with embryonic stem (ES) cells carrying targeted genes are allowed to develop in the uterus of foster mothers. The uterus, however, is like a black box for researchers investigating postimplantation development of mammalian embryos. Embryo culture is one of the powerful techniques that can open this black box. In this review, we focus on the applicable aspects of the whole embryo culture in the study of mammalian development and discuss the future possibilities of this technique. 相似文献
17.
全球气候变化导致的区域森林生长衰退和死亡普遍发生,并对森林生态系统结构和组成以及主要生态系统服务功能产生重要影响,然而相关研究在国内还显偏少。根据黄土高原延安羊圈沟小流域人工刺槐林健康和衰退个体分别构建了刺槐健康和衰退树轮年表,并对人工刺槐林健康和衰退年表特征及对气候响应敏感性进行了对比分析。结果表明刺槐衰退年表质量较低,其年表统计参量,包括平均敏感度、样芯间相关系数、信噪比和样本群体代表系数均要低于刺槐健康年表。刺槐衰退年表在生活史早期(1985-2007年)与生长健康年表的波动趋势相类似,而在生活史晚期(2008-2016年)与健康年表指数出现生长分离现象,生长速率明显偏低。年表与气候要素响应分析表明刺槐生长衰退年表对气候要素响应敏感性要低于刺槐生长健康年表,但是两者均含有干旱胁迫气候信号,主要体现在与温度呈负相关关系,与降雨和干旱指数的正相关关系。年表与极端气候年份的时序叠加分析表明,生长健康和衰退年表对极端干旱年份响应敏感性均较高,表明极端干旱胁迫条件对刺槐生长健康和衰退个体均有抑制性影响;生长健康年表对极端湿润年份响应敏感性明显高于衰退年表,表明刺槐健康个体比衰退个体更能有效利用湿润年份有利条件,而具有较高的生长速率。研究揭示出黄土高原健康和衰退刺槐个体生长趋势变化及对气候响应敏感性均存在明显差异性,将为气候变化背景下人工刺槐林生长衰退和死亡预测模型建立提供科学依据,因而对黄土高原人工刺槐林生态恢复和保护及可持续经营具有科学价值。 相似文献
18.
Dendroprovenancing studies frequently use site chronologies to identify the origin of archaeological and historical timber. However, radial growth (tree-ring width, TRW) of tree species is influenced by both local and regional climate scales. Here we investigate how the use of annually-resolved Blue Intensity (BI) measurements can enhance dendroprovenancing precision of black pine (Pinus nigra Arn.) and Scots pine (P. sylvestris L.) on the Iberian Peninsula. Principal Component Gradient Analyses (PCGA) was used to assess geographical patterns of annual variation in different TRW and BI proxies of pine trees from two mountain ranges in the Central System and Andalusia in Spain. Local climate-growth relationships were quantified to identify underlying causes of identified groups with diverse growth patterns. Two distinct elevational groups were observed when performing PCGA on latewood BI time series with the response to summer drought as the main factor causing the differences. Both P. nigra and P. sylvestris BI time series were found to be more related to summer drought at low-elevation sites showing an increase in sensitivity at lower latitudes. PCGA of TRW time series allowed to discriminate between trees from Andalusia and Central System within the elevation groups. February and October temperatures were found to be the main climatic factors causing the differences in TRW time series among the high- elevation sites, whereas for low-elevation trees it was the average winter temperature influencing TRW. A subsequent leave-one-out analyses confirmed that including latewood BI time series improves the precision of dendroprovenancing of pine wood in the Iberian Peninsula. 相似文献
19.
A C Aufderheide J L Angel J O Kelley A C Outlaw M A Outlaw G Rapp L E Wittmers 《American journal of physical anthropology》1985,66(4):353-361
Lead content was determined in the skeletal tissue of 82 individuals representing two black and two white Colonial American populations: Catoctin Furnace, College Landing, Governor's Land, and Irene Mound. Group and individual differences in bone lead concentrations were used to assess behavioral, social and occupational characteristics. Variations in skeletal lead content suggested that the white owners of the Catoctin iron furnace shared little of their food and beverage with their black, male, industrial slaves, but that some of these workers' women had access to the owners' food sources--probably via domestic duty assignments. A broad range of lead concentrations in bones of the free blacks at College Landing implies a wide range of economic success among these tradesmen. Bone lead content of the white populations at Governor's Land and Irene Mound helped confirm family relationships that had been assigned on an archaeological and osteological basis, and also suggested that the social and functional status of the white tenant farmers' white servants frequently differed little from that of black slaves. These findings suggest that, when applied in appropriate circumstances, lead studies of archaeological skeletal tissue may provide information supplemental to that derived from historical, archaeological, or other conventional sources. 相似文献
20.
LAURA CONDE-FERRÁEZ CEES WAALWIJK BLONDY B. CANTO-CANCHÉ GERT H. J. KEMA PEDRO W. CROUS REW C. JAMES EDWIN C. A. ABELN † 《Molecular Plant Pathology》2007,8(1):111-120
Idiomorphs mat1-1 and mat1-2 from Mycosphaerella fijiensis , the causal agent of black leaf streak disease of banana, were isolated. Degenerate oligos were used to amplify the HMG box of the mat1-2 idiomorph from M. fijiensis , showing homology with the HMG box of Mycosphaerella graminicola. Using a DNA walking strategy, anchored on the DNA lyase gene towards the HMG box, a 9-kb-long region of mat1-2 was obtained. A 5-kb fragment from the mat1-1 region was obtained by long-range PCR using primers on the flanking regions, which have close to 100% identity between both idiomorphs. High-identity (77–89%), inverted regions within both idiomorphs were found, which suggest unique inversion events, which have not been found before, and that could have been significant in the evolution of this species. The predicted genes showed the conserved introns in both idiomorphs as well as an additional intron within the alpha box. The implications for the evolution of species in the Mycosphaerella complex on banana are discussed. 相似文献