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11.
Multiple introductions,admixture and bridgehead invasion characterize the introduction history of Ambrosia artemisiifolia in Europe and Australia 下载免费PDF全文
Lotte A. van Boheemen Eric Lombaert Kristin A. Nurkowski Bertrand Gauffre Loren H. Rieseberg Kathryn A. Hodgins 《Molecular ecology》2017,26(20):5421-5434
Admixture between differentiated populations is considered to be a powerful mechanism stimulating the invasive success of some introduced species. It is generally facilitated through multiple introductions; however, the importance of admixture prior to introduction has rarely been considered. We assess the likelihood that the invasive Ambrosia artemisiifolia populations of Europe and Australia developed through multiple introductions or were sourced from a historical admixture zone within native North America. To do this, we combine large genomic and sampling data sets analysed with approximate Bayesian computation and random forest scenario evaluation to compare single and multiple invasion scenarios with pre‐ and postintroduction admixture simultaneously. We show the historical admixture zone within native North America originated before global invasion of this weed and could act as a potential source of introduced populations. We provide evidence supporting the hypothesis that the invasive populations established through multiple introductions from the native range into Europe and subsequent bridgehead invasion into Australia. We discuss the evolutionary mechanisms that could promote invasiveness and evolutionary potential of alien species from bridgehead invasions and admixed source populations. 相似文献
12.
M. K. Dhami D. N. Gunawardana D. Voice L. Kumarasinghe 《Journal of Applied Entomology》2016,140(7):536-552
Significant plant pests such as fruit flies that travel with fresh produce between countries as eggs or larvae pose a great economic threat to the agriculture and fruit industry worldwide. Time‐limited and expensive quarantine decisions require accurate identification of such pests. Immature stages are often impossible to identify, making them a serious concern for biosecurity agencies. Use of COI barcoding PCR, often the only molecular identification resource, is time‐consuming. We assess the suitability of the COI barcoding region for real‐time PCR assays to identify four pest fruit fly species (Family: Tephritidae), in a diagnostic framework. These species, namely Mediterranean fruit fly (Ceratitis capitata), Queensland fruit fly (Bactrocera tryoni), African invader fly (Bactrocera invadens) and Island fly (Dirioxa pornia) each provide a different set of genetic species delimitation problems. We discuss the benefits and limitations of using a single‐gene TaqMan? real‐time approach for such species. Our results indicate that COI‐based TaqMan? real‐time PCR assays, in particular for genetically distinct species, provide an accurate, sensitive and rapid diagnostic tool. 相似文献
13.
Rafal Krela Elzbieta Poreba Martyna Weglewska Tomasz Skrzypczak Krzysztof Lesniewicz 《Biochimica et Biophysica Acta (BBA)/General Subjects》2019,1863(3):521-527
Background
During standard gene cloning, the recombinant protein appearing in bacteria as the result of expression leakage very often inhibits cell proliferation leading to blocking of the cloning procedure. Although different approaches can reduce transgene basal expression, the recombinant proteins, which even in trace amounts inhibit bacterial growth, can completely prevent the cloning process.Methods
Working to solve the problem of DNase II-like cDNA cloning, we developed a novel cloning approach. The method is based on separate cloning of the 5′ and 3′ fragments of target cDNA into a vector in such a way that the short Multiple Cloning Site insertion remaining between both fragments changes the reading frame and prevents translation of mRNA arising as a result of promoter leakage. Subsequently, to get the vector with full, uninterrupted Open Reading Frame, the Multiple Cloning Site insertion is removed by in vitro restriction/ligation reactions, utilizing the unique restriction site present in native cDNA.Results
Using this designed method, we cloned a coding sequence of AcDNase II that is extremely toxic for bacteria cells. Then, we demonstrated the usefulness of the construct prepared in this way for overexpression of AcDNase II in eukaryotic cells.Conclusions
The designed method allows cloning of toxic protein coding sequences that cannot be cloned by standard methods.General significance
Cloning of cDNAs encoding toxic proteins is still a troublesome problem that hinders the progress of numerous studies. The method described here is a convenient solution to cloning problems that are common in research on toxic proteins. 相似文献14.
Marili Laas Kalev Adamson Irene Barnes Josef Janouek Martin S. Mullett Katarína Adam
íkov Mitsuteru Akiba Ludwig Beenken Helena Braganca Timur S. Bulgakov Paolo Capretti Thomas Cech Michelle Cleary Rasmus Enderle Luisa Ghelardini Libor Jankovský Svetlana Markovskaja Iryna Matsiakh Joana B. Meyer Funda Oskay Barbara Pikur Kristina Raitelaityt Duan Sadikovi Rein Drenkhan 《Molecular Plant Pathology》2022,23(11):1620
Lecanosticta acicola is a pine needle pathogen causing brown spot needle blight that results in premature needle shedding with considerable damage described in North America, Europe, and Asia. Microsatellite and mating type markers were used to study the population genetics, migration history, and reproduction mode of the pathogen, based on a collection of 650 isolates from 27 countries and 26 hosts across the range of L. acicola. The presence of L. acicola in Georgia was confirmed in this study. Migration analyses indicate there have been several introduction events from North America into Europe. However, some of the source populations still appear to remain unknown. The populations in Croatia and western Asia appear to originate from genetically similar populations in North America. Intercontinental movement of the pathogen was reflected in an identical haplotype occurring on two continents, in North America (Canada) and Europe (Germany). Several shared haplotypes between European populations further suggests more local pathogen movement between countries. Moreover, migration analyses indicate that the populations in northern Europe originate from more established populations in central Europe. Overall, the highest genetic diversity was observed in south‐eastern USA. In Europe, the highest diversity was observed in France, where the presence of both known pathogen lineages was recorded. Less than half of the observed populations contained mating types in equal proportions. Although there is evidence of some sexual reproduction taking place, the pathogen spreads predominantly asexually and through anthropogenic activity. 相似文献
15.
Angela C. Bartlett Tim M. Blackburn Rod Randall Jane A. Catford 《Global Ecology and Biogeography》2023,32(7):1163-1177
Aim
Directly or indirectly, humans select the plants that they transport and introduce outside of species native ranges. Plants that have become invasive may therefore reflect which species had the chance to invade, rather than which species would become invasive given the chance. We examine characteristics of failed introductions, along with invasion successes, by investigating (a) variation in plant characteristics across invasion stages, and (b) how observed characteristics predict the likelihood of species moving through invasion stages.Location
Australia.Time period
1770s to present.Major taxa studied
34,650 plant species, across 424 families.Methods
We used a comprehensive list of 34,650 plant species that are known to have been introduced to Australia, 4,081 of which are classified as naturalized and 428 as invasive. We represent plant characteristics with categorical growth forms, three functional traits (plant height, seed mass, and specific leaf area) and three factors related to species introduction histories (native regions, purpose, and minimum residence times).Results
(a) The types of species introduced determine the types of species that naturalize and become invasive; (b) species introduction histories predict the likelihood of species moving through invasion stages; and (c) the numbers of species naturalizing (~15%) and becoming invasive (~15%) slightly exceeds expectation from the “tens rule”, which expects that 10% of introduced species naturalize and 10% become invasive.Main conclusions
Our findings are significant for global biosecurity, indicating that functional traits alone cannot be used to predict a species' risk of becoming invasive. Rather, evidence suggests that characteristics of species introductions—specifically, a longer time-lag since first introduction and more pathways of introduction—define the relative risks of species moving through invasion stages. This is important for assessing future invasion risks, as future introductions may differ from those of the past. Our work highlights the need to reduce the number of species introduced. 相似文献16.
Rafael Muñoz-Mas Franz Essl Mark van Kleunen Hanno Seebens Wayne Dawson Christine Marie V. Casal Emili García-Berthou 《Global Ecology and Biogeography》2023,32(9):1632-1644
Aim
Investigating major freshwater fish flows (translocations) between biogeographic regions and their temporal dynamics and also quantifying spatial patterns and temporal changes in the array of introduced species, and the emergence and distance between major donor and recipient regions.Location
Global.Time Period
1800–2020.Major Taxa Studied
Freshwater fishes.Methods
We analysed a global dataset on freshwater fish introductions (4241 events of 688 species). Freshwater fish flows were investigated with flow diagrams and χ2 tests, while PERMANOVA (permutational multivariate analysis of variance) was used to test the association between species and regions and temporal shifts. Cluster analysis revealed major recipient areas and composition of the introduced species. Finally, changes in distances between donor and recipient sites were tested with PERMANOVA.Results
The number of introductions between biogeographic regions mirrored the European and North American dominance before World War II (WWII) and the trends in recreational fishing, biocontrol programmes and food production, especially in the Sino-Oriental region, which has a long tradition of aquaculture and fishkeeping. Over the years, the origins and composition of introduced species changed uniquely in each biogeographic region, although the most introduced species are common to every region. Salmonids and other cold-water species were frequently introduced before the 1950s, whereas tropical ornamental and aquaculture species currently prevail. Distances between donor and recipient sites did not vary over the time. After WWII, the Sino-Oriental region consolidated its dominance and the Ethiopian and Neotropical regions emerged as new global donor and recipient regions.Main Conclusions
Global policy should focus on tropical ornamental and aquaculture species, which could benefit from global warming, especially in the Sino-Oriental region, because it currently dominates freshwater fish species flows, and the Ethiopian and Neotropical regions, because they recently emerged as important global donor and recipient regions of freshwater fish introductions. 相似文献17.
18.
宁夏国外小麦种质资源考察、引进和利用 总被引:2,自引:0,他引:2
国外小麦种质资源引进在宁夏小麦引种中发挥着重要的作用。碧玉麦、阿勃、墨卡(卡杰姆F-71)、WC-20(宁春37)、9186(宁冬6号)等国外小麦品种在宁夏生产上直接利用。宁夏春小麦的品质杂交选育始于1953年,利用国外小麦种质资源先后培育出斗地1号、宁春4号等50余个春麦品种。1990年宁夏国外冬麦种质资源的引进带动了宁夏引黄灌区冬麦北移和耕作改制的研究,也引发了宁夏冬麦品种杂交选育的研究。宁夏引黄灌区冬小麦品种的杂交选育的工作始于1991年,经过15年的努力,杂交选育出第一批冬麦品种宁冬10号、宁冬11号,2010年在冬麦生产上取代了明丰5088,不仅实现了宁夏引黄灌区冬小麦品种第3次更新、实现了小麦品种的5次更新,而且使宁夏小麦生产水平跃上新台阶,有力地促进宁夏引黄灌区耕作制度改善和种植业结构的调整。 相似文献
19.
苦丁茶在海南儋州的引种试种 总被引:1,自引:0,他引:1
在海南儋州进行苦丁茶引种试验。结果表明,儋州地区适宜种植苦丁茶,且能获得较高产量。田间试验表明,适当遮阳能促进植株的生长,灌溉是种植成功并获得高产的重要条件;生产中要加强技术管理,培养合理的树冠,以便保持持续的高产、稳产。 相似文献
20.
桑白蚧恩蚜小蜂Encarsia(=Prospaltella)berlesel(Howard)是寄生桑白蚧Pseudaulacaspls pentagona(Targioni-Tozzctti)的重要寄生蜂,许多国家进行了引进移植,对控制桑白蚧的为害取得明显的成效.本记述了桑白蚧恩蚜小蜂形态特征的鉴别。以及各国引进利用的概况.并讨论了利用寄生蜂防治桑白蚧的重要性. 相似文献