scholarly journals Grain trade between China and the United States shapes the spatial genetic pattern of common ragweed populations in East China cities

Author(s):  
Siran lu ◽  
Xiangyu Luo ◽  
Hongfang Wang ◽  
Rodolfo Gentili ◽  
Sandra Citterio ◽  
...  

Abstract Common ragweed (Ambrosia artemisiifolia L.) is an invasive alien species (IAS) that can cause severe allergies among urban residents. Understanding its invasion pathways is critical for designing effective control programs. However, studies on the invasion of common ragweed normally skip urban areas. Results from a few studies based on analyzing occurrence records contain high uncertainties. We attempted to address this knowledge gap through a case study in East China cities by combining the population genetic method with the occurrence records. We first collected leaf samples of 37 common ragweed populations from 15 cities. We then quantified the spatial genetic pattern of common ragweed populations by analyzing genomic and chloroplast DNA extracted from the leaf samples. Combined with the analysis of occurrence data and trade data, we discovered that multiple introductions have impacted the spatial genetic pattern of common ragweed populations in East China Cities. We inferred that the modern-day grain trade between the United States and China could be the primary invasion source while the bridgehead introduction passage through Japan played a minor role. Among the studied cities, Nanjing and Shenyang dispersed more gene flows than other cities. The two cities' central roles in transportation and grain importation might explain the observed pattern. Based on our findings, we suggest that invasive species control programs should consider the potential role of cities as landing points and dispersal hubs of common ragweed in invaded countries.

1989 ◽  
Vol 52 (8) ◽  
pp. 595-601 ◽  
Author(s):  
EWEN C. D. TODD

Although the full economic impact of foodborne diseases has yet to be measured, preliminary studies show that the cost of illness, death, and business lost is high indeed. This impact is probably greatest in developing countries, but few facts are known. For the United States, preliminary estimates are 12.6 million cases costing $8.4 billion. These may seem excessive but other authors have postulated even higher case and dollar figures. Microbiological diseases (bacterial and viral) represent 84% of the United States' costs, with salmonellosis and staphylococcal intoxication being the most economically important diseases (annually $4.0 billion and $1.5 billion, respectively). Other costly types of illnesses are toxoplasmosis ($445 million), listeriosis ($313 million), campylobacteriosis ($156 million), trichinosis ($144 million), Clostridium perfringens enteritis ($123 million), and E. coli infections including hemorrhagic colitis ($223 million). Botulism has a high cost per case ($322,200), but its total impact is only $87 million because relatively few cases occur (270). This is because the food industry has been able to introduce effective control measures. Salmonellosis, however, is much more widespread (2.9 million cases) and affects all sectors of the food industry.


2010 ◽  
Vol 11 (1) ◽  
pp. 32 ◽  
Author(s):  
Christian A. Wyenandt ◽  
Steven L. Rideout ◽  
Beth K. Gugino ◽  
Margaret T. McGrath ◽  
Kathryne L. Everts ◽  
...  

Foliar diseases and fruit rots occur routinely on tomato, an important crop grown throughout the Mid-Atlantic and Northeast regions of the United States where it is produced for both fresh-market and processing. To enable these tomato growers to more effectively manage economically important diseases, a fungicide resistance management table has been developed which promotes the importance of understanding FRAC (Fungicide Resistance Action Committee) codes and provides an integrated pest management tool for tomato growers which will allow them to develop season-long disease control programs with an emphasis on fungicide resistance management. Accepted for publication 19 July 2010. Published 27 August 2010.


2013 ◽  
Vol 27 (2) ◽  
pp. 291-297 ◽  
Author(s):  
Kelly A. Barnett ◽  
A. Stanley Culpepper ◽  
Alan C. York ◽  
Lawrence E. Steckel

Glyphosate-resistant (GR) weeds, especially GR Palmer amaranth, are very problematic for cotton growers in the Southeast and Midsouth regions of the United States. Glufosinate can control GR Palmer amaranth, and growers are transitioning to glufosinate-based systems. Palmer amaranth must be small for consistently effective control by glufosinate. Because this weed grows rapidly, growers are not always timely with applications. With widespread resistance to acetolactate synthase-inhibiting herbicides, growers have few herbicide options to mix with glufosinate to improve control of larger weeds. In a field study using a WideStrike®cotton cultivar, we evaluated fluometuron at 140 to 1,120 g ai ha−1mixed with the ammonium salt of glufosinate at 485 g ae ha−1for control of GR Palmer amaranth 13 and 26 cm tall. Standard PRE- and POST-directed herbicides were included in the systems. Glufosinate alone injured the WideStrike® cotton less than 10%. Fluometuron increased injury up to 25% but did not adversely affect yield. Glufosinate controlled 13-cm Palmer amaranth at least 90%, and there was no improvement in weed control nor a cotton yield response to fluometuron mixed with glufosinate. Palmer amaranth 26 cm tall was controlled only 59% by glufosinate. Fluometuron mixed with glufosinate increased control of the larger weeds up to 28% and there was a trend for greater yields. However, delaying applications until weeds were 26 cm reduced yield 22% relative to timely application. Our results suggest fluometuron mixed with glufosinate may be of some benefit when attempting to control large Palmer amaranth. However, mixing fluometuron with glufosinate is not a substitute for a timely glufosinate application.


Author(s):  
Robert S. Ross

This chapter examines alliance dynamics in U.S.–China relations in Northeast Asia. It analyzes how each nation has used third-party coercive diplomacy to compel the other to restrain its allies' challenges to great power security. A major objective of U.S. policy toward North Korea and the corresponding tension of the Korean Peninsula has been to compel China to exercise greater control over North Korea's nuclear weapons program. A major objective of Chinese policy toward Japan and the corresponding tension in the East China Sea has been to compel the United States to restrain Japanese challenges to Chinese sovereignty claims in disputed waters in the East China Sea. For a brief period, third-party coercion contributed to greater U.S.–China cooperation as each country adjusted its policies toward its respective ally, easing regional tension and U.S.–China conflict.


Worldview ◽  
1982 ◽  
Vol 25 (12) ◽  
pp. 8-10 ◽  
Author(s):  
Lester R. Brown

Each day two 20,000-ton freighters loaded with grain leave the United States for the Soviet Union. This flow of grain between two major adversaries is influenced by economic considerations such as the size of the Soviet grain deficit, the U.S. capacity to supply, and the Soviet ability to pay. Political considerations include the risk to both trading partners of such a heavy interdependence, whether as supplier or market.Never before has a country dominated the world grain trade as the United States does today. Its 55 per cent share of world grain exports in 1981 easily overshadows Saudi Arabia's 24 per cent share of world oil exports in 1978. And while the amount of oil traded internationally has been falling since 1979, grain shipments are continuing to grow.


2001 ◽  
Vol 2001 (1) ◽  
pp. 3-24 ◽  
Author(s):  
Gary Tannahill ◽  
Alexis Steen

ABSTRACT Since its inception, the Oil Pollution Act of 1990 (OPA 90) was intended to greatly improve the ability to respond to large spills in the United States and has been the subject of frequent discussion and debate within the United States and elsewhere. Its provisions created new regulatory programs, expanded existing requirements, and established a variety of competency requirements for those entities and personnel involved in the production, transport, handling, or storage of petroleum within the United States. Tens upon tens of articles have been published in prior Proceedings of the International Oil Spill Conference (IOSC) and in many other venues about legislative intent, subsequent regulatory programs and their implementation, interagency negotiations, industry compliance successes or difficulties, training issues, etc. OPA 90 has also had an impact on U.S. policies internationally and in U.S. participation in international spill conventions/treaties. In recognition of a decade's passage since its enactment, IOSC sponsors commissioned a review and analysis of the effectiveness of OPA 90 and the interrelationship of OPA 90 with other oil spill laws and rules in the world. Another important purpose was to identify issues for the related panel discussion of this topic at the 2001 IOSC. This review was conducted using a questionnaire to acquire input from a broad range of individuals with OPA 90 expertise and experience. An informal survey of 57 questions in four sections was prepared and distributed to 22 participants. These participants were selected to represent a core of knowledge about OPA 90 and its history of implementation. Findings from the survey are presented to foster discussion and debate, educate members of the spill response community, assist with resolution of outstanding issues, and help focus on future issues that will need attention. The rate of response to the survey questions was high and enabled a broad review of the effectiveness of some of the various OPA 90 requirements. Questions were in either multiple-choice or essay format. Commonalties, differences, and issues were identified from all responses and used to evaluate OPA 90. From the commonalties and differences in the responses, selected OPA 90 requirements were classified as effective or ineffective. Based on an analysis of multiple-choice and essay answers, respondents generally agreed that OPA 90 was moderately effective (across all covered provisions). Closer examination of the four survey sections, however, indicated distinct concerns and benefits derived from implementation of OPA 90. In addition, where OPA 90 provisions were judged effective, caveats sometimes followed. Despite the effective rating of many OPA 90 prevention provisions, prevention still needs more attention based on the opinions of the survey respondents. Some respondents felt more attention and resources often are given to preparing to respond to a spill than to preventing spills, even though preventing a spill is considered preferable. Further, some believed that spill prevention would be enhanced if vessels with large, onboard bunker fuel storage also were subject to prevention requirements similar to OPA 90 requirements for vessels carrying petroleum as cargo. Survey feedback indicated that better Area Contingency Plans (ACPs) could result in significant improvements in response preparedness. ACPs need to be improved in many geographic areas. ACPs should be more response-oriented and less like a reference document, and be made more readily available and useable. Many respondents viewed these items as the foundation for any major improvements in response planning. In the United States, spill response using a multiparty management system, which is inclusive of broad stakeholder groups, differs from systems in other countries. Most felt that response activities can impact restoration activities greatly, but the legal structure does not support a seamless and efficient coordination of response and restoration. Coordination between response and restoration needs to be improved to avoid response delays and promote better/faster resource restoration. The biggest concern expressed by survey respondents regarding restoration dealt with management of the Natural Resource Damage Assessment (NRDA) process. Damage assessments and restoration management need to be streamlined, partly because too many interested parties make decision making inefficient. Some felt that public review of restoration plans led to better results; others felt public review delayed timely restoration activities. While international cooperation has increased over the last decade, respondents felt there was room for further improvement. In particular, sharing personnel and resources better, joining inspection and control programs, and drafting international restoration guidelines were some of the improvement activities mentioned. Findings from this survey have provided insights on what actions are needed to further improve spill prevention, preparedness, response, and restoration. Now is the time to renew this effort and improve performance to a higher plane globally. 2001 IOSC sponsors and Issue Paper Subcommittee desire the response community's commitment and solicit its involvement toward this goal.


Plant Disease ◽  
2015 ◽  
Vol 99 (4) ◽  
pp. 428-441 ◽  
Author(s):  
Gerald J. Holmes ◽  
Peter S. Ojiambo ◽  
Mary K. Hausbeck ◽  
Lina Quesada-Ocampo ◽  
Anthony P. Keinath

In 2004, an outbreak of cucurbit downy mildew (CDM) caused by the oomycete Pseudoperonospora cubensis (Berk. & M. A. Curtis) Rostovzev resulted in an epidemic that stunned the cucumber (Cucumis sativus L.) industry in the eastern United States. The disease affects all major cucurbit crops, including cucumber, muskmelon, squashes, and watermelon. Although the 2004 epidemic began in North Carolina, the cucumber crop from Florida to the northern growing regions in the United States was devastated, resulting in complete crop loss in several areas. Many cucumber fields were abandoned prior to harvest. The rapid spread of the disease coupled with the failure of fungicide control programs surprised growers, crop consultants, and extension specialists. The epidemic raised several fundamental questions about the potential causes for the resurgence of the disease. Some of these questions revolved around whether the epidemic would recur in subsequent years and the possible roles that changes in the host, pathogen, and environment may have played in the epidemic.


2000 ◽  
Vol 28 (6) ◽  
pp. 392-400 ◽  
Author(s):  
Giang T. Nguyêñ ◽  
Suzanne E. Proctor ◽  
Ronda L. Sinkowitz-Cochran ◽  
Denise O. Garrett ◽  
William R. Jarvis

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