WorldWideScience

Sample records for biological control

  1. Integrated Biological Control

    International Nuclear Information System (INIS)

    Biological control is any activity taken to prevent, limit, clean up, or remediate potential environmental, health and safety, or workplace quality impacts from plants, animals, or microorganisms. At Hanford the principal emphasis of biological control is to prevent the transport of radioactive contamination by biological vectors (plants, animals, or microorganisms), and where necessary, control and clean up resulting contamination. Other aspects of biological control at Hanford include industrial weed control (e.g.; tumbleweeds), noxious weed control (invasive, non-native plant species), and pest control (undesirable animals such as rodents and stinging insects; and microorganisms such as molds that adversely affect the quality of the workplace environment). Biological control activities may be either preventive (apriori) or in response to existing contamination spread (aposteriori). Surveillance activities, including ground, vegetation, flying insect, and other surveys, and apriori control actions, such as herbicide spraying and placing biological barriers, are important in preventing radioactive contamination spread. If surveillance discovers that biological vectors have spread radioactive contamination, aposteriori control measures, such as fixing contamination, followed by cleanup and removal of the contamination to an approved disposal location are typical response functions. In some cases remediation following the contamination cleanup and removal is necessary. Biological control activities for industrial weeds, noxious weeds and pests have similar modes of prevention and response

  2. Insecticides and Biological Control

    Science.gov (United States)

    Furness, G. O.

    1972-01-01

    Use of insecticides has been questioned due to their harmful effects on edible items. Biological control of insects along with other effective practices for checking spread of parasites on crops are discussed. (PS)

  3. Biological control of ticks

    Science.gov (United States)

    Samish, M.; Ginsberg, H.; Glazer, I.; Bowman, A.S.; Nuttall, P.

    2004-01-01

    Ticks have numerous natural enemies, but only a few species have been evaluated as tick biocontrol agents (BCAs). Some laboratory results suggest that several bacteria are pathogenic to ticks, but their mode of action and their potential value as biocontrol agents remain to be determined. The most promising entomopathogenic fungi appear to be Metarhizium anisopliae and Beauveria bassiana, strains of which are already commercially available for the control of some pests. Development of effective formulations is critical for tick management. Entomopathogenic nematodes that are pathogenic to ticks can potentially control ticks, but improved formulations and selection of novel nematode strains are needed. Parasitoid wasps of the genus Ixodiphagus do not typically control ticks under natural conditions, but inundative releases show potential value. Most predators of ticks are generalists, with a limited potential for tick management (one possible exception is oxpeckers in Africa). Biological control is likely to play a substantial role in future IPM programmes for ticks because of the diversity of taxa that show high potential as tick BCAs. Considerable research is required to select appropriate strains, develop them as BCAs, establish their effectiveness, and devise production strategies to bring them to practical use.

  4. Biological pest control in Mexico.

    Science.gov (United States)

    Williams, Trevor; Arredondo-Bernal, Hugo C; Rodríguez-del-Bosque, Luis A

    2013-01-01

    Mexico is a megadiverse country that forms part of the Mesoamerican biological corridor that connects North and South America. Mexico's biogeographical situation places it at risk from invasive exotic insect pests that enter from the United States, Central America, or the Caribbean. In this review we analyze the factors that contributed to some highly successful past programs involving classical biological control and/or the sterile insect technique (SIT). The present situation is then examined with reference to biological control, including SIT programs, targeted at seven major pests, with varying degrees of success. Finally, we analyze the current threats facing Mexico's agriculture industry from invasive pests that have recently entered the country or are about to do so. We conclude that despite a number of shortcomings, Mexico is better set to develop biological control-based pest control programs, particularly on an area-wide basis, than many other Latin American countries are. Classical and augmentative biological control and SIT-based programs are likely to provide effective and sustainable options for control of native and exotic pests, particularly when integrated into technology packages that meet farmers' needs across the great diversity of production systems in Mexico.

  5. Herbivory, Predation, and Biological Control.

    Science.gov (United States)

    Murphy, Terence M.; And Others

    1992-01-01

    Authors describe a set of controlled ecosystems that can be used to demonstrate the effects of herbivory on the health and growth of a plant population and of predation on the growth of a primary consumer population. The system also shows the effectiveness of biological pest control measures in a dramatic way. The construction of the ecosystems is…

  6. Biological control in greenhouse systems.

    Science.gov (United States)

    Paulitz, T C; Bélanger, R R

    2001-01-01

    The controlled environment of greenhouses, the high value of the crops, and the limited number of registered fungicides offer a unique niche for the biological control of plant diseases. During the past ten years, over 80 biocontrol products have been marketed worldwide. A large percentage of these have been developed for greenhouse crops. Products to control soilborne pathogens such as Sclerotinia, Pythium, Rhizoctonia and Fusarium include Coniothyrium minitans, species of Gliocladium, Trichoderma, Streptomyces, and Bacillus, and nonpathogenic Fusarium. Products containing Trichoderma, Ampelomyces quisqualis, Bacillus, and Ulocladium are being developed to control the primary foliar diseases, Botrytis and powdery mildew. The development of Pseudomonas for the control of Pythium diseases in hydroponics and Pseudozyma flocculosa for the control of powdery mildew by two Canadian research programs is presented. In the future, biological control of diseases in greenhouses could predominate over chemical pesticides, in the same way that biological control of greenhouse insects predominates in the United Kingdom. The limitations in formulation, registration, and commercialization are discussed, along with suggested future research priorities. PMID:11701861

  7. Intestinal nematodes: biology and control.

    Science.gov (United States)

    Epe, Christian

    2009-11-01

    A variety of nematodes occur in dogs and cats. Several nematode species inhabit the small and large intestines. Important species that live in the small intestine are roundworms of the genus Toxocara (T canis, T cati) and Toxascaris (ie, T leonina), and hookworms of the genus Ancylostoma (A caninum, A braziliense, A tubaeforme) or Uncinaria (U stenocephala). Parasites of the large intestine are nematodes of the genus Trichuris (ie, whipworms, T vulpis). After a comprehensive description of their life cycle and biology, which are indispensable for understanding and justifying their control, current recommendations for nematode control are presented and discussed thereafter. PMID:19932365

  8. Review of Pasteuria penetrans: Biology, Ecology, and Biological Control Potential

    OpenAIRE

    Chen, Z. X.; Dickson, D. W.

    1998-01-01

    Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite that has shown great potential as a biological control agent of root-knot nematodes. Considerable progress has been made during the last 10 years in understanding its biology and importance as an agent capable of effectively suppressing root-knot nematodes in field soil. The objective of this review is to summarize the current knowledge of the biology, ecology, and biological control potential of P. penetrans and other P...

  9. "Protected biological control"- Biological pest management in the greenhouse industry

    NARCIS (Netherlands)

    Pilkington, L.J.; Messelink, G.J.; Lenteren, van J.C.; Mottee, Le K.

    2010-01-01

    This paper briefly describes the foundations and characteristics of biological control in protected cropping and what drivers are behind adoption of this management system within this industry. Examining a brief history of biological control in greenhouses and what makes it a successful management s

  10. Controlling Sulfuryl-Transfer Biology.

    Science.gov (United States)

    Cook, Ian; Wang, Ting; Wang, Wei; Kopp, Felix; Wu, Peng; Leyh, Thomas S

    2016-05-19

    In humans, the cytosolic sulfotransferases (SULTs) catalyze regiospecific transfer of the sulfuryl moiety (-SO3) from 3'-phosphoadenosine 5'-phosphosulfate to thousands of metabolites, including numerous signaling small molecules, and thus regulates their activities and half-lives. Imbalances in the in vivo set points of these reactions leads to disease. Here, with the goal of controlling sulfonation in vivo, molecular ligand-recognition principles in the SULT and nuclear receptor families are integrated in creating a strategy that can prevent sulfonation of a compound without significantly altering its receptor affinity, or inhibiting SULTS. The strategy is validated by using it to control the sulfonation and estrogen receptor (ER) activating activity of raloxifene (a US Food and Drug Administration-approved selective estrogen receptor modulator) and its derivatives. Preventing sulfonation is shown to enhance ER-activation efficacy 10(4)-fold in studies using Ishikawa cells. The strategy offers the opportunity to control sulfuryl transfer on a compound-by-compound basis, to enhance the efficacy of sulfonated drugs, and to explore the biology of sulfuryl transfer with unprecedented precision. PMID:27203377

  11. Biological control and sustainable food production

    NARCIS (Netherlands)

    Bale, J.S.; Lenteren, van J.C.; Bigler, F.

    2008-01-01

    The use of biological control for the management of pest insects pre-dates the modern pesticide era. The first major successes in biological control occurred with exotic pests controlled by natural enemy species collected from the country or area of origin of the pest (classical control). Augmentati

  12. Biology and Water Pollution Control.

    Science.gov (United States)

    Warren, Charles E.

    Within this text, the reader is attuned to the role biology can and should play in combating the alarming increase in water pollution. Both the urgency of the problem and the biological techniques that are being developed to cope with the water pollution crisis are scrutinized; what is and is not known about the problem is explained; past,…

  13. Biological Control in Brazil: an overview

    OpenAIRE

    José Roberto Postali Parra

    2014-01-01

    The use of Biological Control methods is on the increase, mainly as a result of the mobilization of human resources in entomology studies since the establishment of graduate programs in this country in the 1960s. This review approaches the retrospective of Biological Control in Brazil in recent decades, with an emphasis on the "culture of applying agrochemicals" adopted by Brazilian growers, which constrains progress in this area. Successful cases of Biological Control have been reported on i...

  14. The biological control of disease vectors.

    Science.gov (United States)

    Okamoto, Kenichi W; Amarasekare, Priyanga

    2012-09-21

    Vector-borne diseases are common in nature and can have a large impact on humans, livestock and crops. Biological control of vectors using natural enemies or competitors can reduce vector density and hence disease transmission. However, the indirect interactions inherent in host-vector disease systems make it difficult to use traditional pest control theory to guide biological control of disease vectors. This necessitates a conceptual framework that explicitly considers a range of indirect interactions between the host-vector disease system and the vector's biological control agent. Here we conduct a comparative analysis of the efficacy of different types of biological control agents in controlling vector-borne diseases. We report three key findings. First, highly efficient predators and parasitoids of the vector prove to be effective biological control agents, but highly virulent pathogens of the vector also require a high transmission rate to be effective. Second, biocontrol agents can successfully reduce long-term host disease incidence even though they may fail to reduce long-term vector densities. Third, inundating a host-vector disease system with a natural enemy of the vector has little or no effect on reducing disease incidence, but inundating the system with a competitor of the vector has a large effect on reducing disease incidence. The comparative framework yields predictions that are useful in developing biological control strategies for vector-borne diseases. We discuss how these predictions can inform ongoing biological control efforts for host-vector disease systems.

  15. Use of nuclear techniques in biological control

    International Nuclear Information System (INIS)

    As pointed out by Benbrook (1996), pest management is at a crossroads, and there is a great need for new, biointensive pest management strategies. Among these approaches, biological control is a keystone. However, because of increasing concerns about the introduction of exotic natural enemies of insect pests and weeds (Howarth 1991, Delfosse 1997), the overall thrust of biological control has moved toward augmentative biological control, involving releases of established natural enemy species (Knipling 1992). This in turn has created a need to develop more cost-effective mass rearing technologies for beneficial insects. Nuclear techniques could play an especially important role in augmentative biological control, not only in facilitating mass rearing, but in several other ways, as indicated below. Recognising the potential value for use of nuclear techniques in biological control, the Insect and Pest Control Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, sponsored a Consultants' Group Meeting on this subject in April 1997. The Group produced a document entitled Use of Nuclear Techniques in Biological Control: Managing Pests, Facilitating Trade and Protecting the Environment. The consultants included the authors of this paper as well as Ernest Delfosse (at that time, with the USDA-APHIS National Biological Control Institute), Garry Hill (Intl. Institute for Biological Control), Sinthya Penn (Beneficial Insectary), and Felipe Jeronimo (USDA-APHIS PPQ, Guatemala). The remarks presented in this paper reflect the thoughts presented by these consultants and other participants at the IAEA-sponsored meeting. Several potential uses for nuclear techniques were identified by the Consultants' Group, including: 1) improvements in rearing media (either artificial diets or natural hosts/prey), 2) provision of sterilised natural prey to be used as food during shipment, to ameliorate concerns relating to the

  16. Biology & control of Anopheles culicifacies Giles 1901.

    Science.gov (United States)

    Sharma, V P; Dev, V

    2015-05-01

    Malaria epidemiology is complex due to multiplicity of disease vectors, sibling species complex and variations in bionomical characteristics, vast varied terrain, various ecological determinants. There are six major mosquito vector taxa in India, viz. Anopheles culicifacies, An. fluviatilis, An. stephensi, An. minimus, An. dirus and An. sundaicus. Among these, An. culicifacies is widely distributed and considered the most important vector throughout the plains and forests of India for generating bulk of malaria cases (>60% annually). Major malaria epidemics are caused by An. culicifaices. It is also the vector of tribal malaria except parts of Odisha and Northeastern States of India. An. culicifacies has been the cause of perennial malaria transmission in forests, and over the years penetrated the deforested areas of Northeast. An. culicifacies participates in malaria transmission either alone or along with An. stephensi or An. fluviatilis. The National Vector Borne Disease Control Programme (NVBDCP) spends about 80 per cent malaria control budget annually in the control of An. culicifacies, yet it remains one of the most formidable challenges in India. With recent advances in molecular biology there has been a significant added knowledge in understanding the biology, ecology, genetics and response to interventions, requiring stratification for cost-effective and sustainable malaria control. Research leading to newer interventions that are evidence-based, community oriented and sustainable would be useful in tackling the emerging challenges in malaria control. Current priority areas of research should include in-depth vector biology and control in problem pockets, preparation of malaria-risk maps for focused and selective interventions, monitoring insecticide resistance, cross-border initiative and data sharing, and coordinated control efforts for achieving transmission reduction, and control of drug-resistant malaria. The present review on An. culicifacies

  17. The Biological Control of the Malaria Vector

    Directory of Open Access Journals (Sweden)

    Layla Kamareddine

    2012-09-01

    Full Text Available The call for malaria control, over the last century, marked a new epoch in the history of this disease. Many control strategies targeting either the Plasmodium parasite or the Anopheles vector were shown to be effective. Yet, the emergence of drug resistant parasites and insecticide resistant mosquito strains, along with numerous health, environmental, and ecological side effects of many chemical agents, highlighted the need to develop alternative tools that either complement or substitute conventional malaria control approaches. The use of biological means is considered a fundamental part of the recently launched malaria eradication program and has so far shown promising results, although this approach is still in its infancy. This review presents an overview of the most promising biological control tools for malaria eradication, namely fungi, bacteria, larvivorous fish, parasites, viruses and nematodes.

  18. Biological control of aflatoxin contamination of crops

    Institute of Scientific and Technical Information of China (English)

    Yan-ni YIN; Lei-yan YAN; Jin-hua JIANG; Zhong-hua MA

    2008-01-01

    Aflatoxins produced primarily by two closely related fungi, Aspergillus flavus and Aspergillus parasiticus, are mutagenic and carcinogenic in animals and humans. Of many approaches investigated to manage aflatoxin contamination, biological control method has shown great promise. Numerous organisms, including bacteria, yeasts and nontoxigenic fungal strains of A.flavus and A. parasiticus, have been tested for their ability in controlling aflatoxin contamination. Great successes in reducing aflatoxin contamination have been achieved by application of nontoxigenic strains of A. flavus and A. parasiticus in fields of cotton, peanut, maize and pistachio. The nontoxigenic strains applied to soil occupy the same niches as the natural occurring toxigenic strains. They, therefore, are capable of competing and displacing toxigenic strains. In this paper, we review recent development in biological control of aflatoxin contamination.

  19. Landscape Structure and Biological Control in Agroecosystems

    OpenAIRE

    Thies, Carsten; Tscharntke, Teja

    1999-01-01

    Biological pest control has primarily relied on local improvements in populations of natural enemies, but landscape structure may also be important. This is shown here with experiments at different spatial scales using the rape pollen beetle (Meligethes aeneus), an important pest on oilseed rape (Brassica napus). The presence of old field margin strips along rape fields was associated with increased mortality of pollen beetles resulting from parasitism and adjacent, large, old fallow habit...

  20. Onchocerciasis control: biological research is still needed

    Directory of Open Access Journals (Sweden)

    Boussinesq M.

    2008-09-01

    Full Text Available Achievements obtained by the onchocerciasis control programmes should not lead to a relaxation in the biological research on Onchocerca volvulus. Issues such as the Loa loa-related postivermectin serious adverse events, the uncertainties as to whether onchocerciasis can be eliminated by ivermectin treatments, and the possible emergence of ivermectin-resistant O. volvulus populations should be addressed proactively. Doxycycline, moxidectin and emodepside appear to be promising as alternative drugs against onchocerciasis but support to researches in immunology and genomics should also be increased to develop new control tools, including both vaccines and macrofilaricidal drugs.

  1. The reverse control of irreversible biological processes.

    Science.gov (United States)

    Cho, Kwang-Hyun; Joo, Jae Il; Shin, Dongkwan; Kim, Dongsan; Park, Sang-Min

    2016-09-01

    Most biological processes have been considered to be irreversible for a long time, but some recent studies have shown the possibility of their reversion at a cellular level. How can we then understand the reversion of such biological processes? We introduce a unified conceptual framework based on the attractor landscape, a molecular phase portrait describing the dynamics of a molecular regulatory network, and the phenotype landscape, a map of phenotypes determined by the steady states of particular output molecules in the attractor landscape. In this framework, irreversible processes involve reshaping of the phenotype landscape, and the landscape reshaping causes the irreversibility of processes. We suggest reverse control by network rewiring which changes network dynamics with constant perturbation, resulting in the restoration of the original phenotype landscape. The proposed framework provides a conceptual basis for the reverse control of irreversible biological processes through network rewiring. WIREs Syst Biol Med 2016, 8:366-377. doi: 10.1002/wsbm.1346 For further resources related to this article, please visit the WIREs website. PMID:27327189

  2. AN INTEGRATED BIOLOGICAL CONTROL SYSTEM AT HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    JOHNSON AR; CAUDILL JG; GIDDINGS RF; RODRIGUEZ JM; ROOS RC; WILDE JW

    2010-02-11

    In 1999 an integrated biological control system was instituted at the U.S. Department of Energy's Hanford Site. Successes and changes to the program needed to be communicated to a large and diverse mix of organizations and individuals. Efforts at communication are directed toward the following: Hanford Contractors (Liquid or Tank Waste, Solid Waste, Environmental Restoration, Science and Technology, Site Infrastructure), General Hanford Employees, and Hanford Advisory Board (Native American Tribes, Environmental Groups, Local Citizens, Washington State and Oregon State regulatory agencies). Communication was done through direct interface meetings, individual communication, where appropriate, and broadly sharing program reports. The objectives of the communication efforts was to have the program well coordinated with Hanford contractors, and to have the program understood well enough that all stakeholders would have confidence in the work performed by the program to reduce or elimated spread of radioactive contamination by biotic vectors. Communication of successes and changes to an integrated biological control system instituted in 1999 at the Department of Energy's Hanford Site have required regular interfaces with not only a diverse group of Hanford contractors (i.e., those responsible for liquid or tank waste, solid wastes, environmental restoration, science and technology, and site infrastructure), and general Hanford employees, but also with a consortium of designated stake holders organized as the Hanford Advisory Board (i.e., Native American tribes, various environmental groups, local citizens, Washington state and Oregon regulatory agencies, etc.). Direct interface meetings, individual communication where appropriate, and transparency of the biological control program were the methods and outcome of this effort.

  3. An Integrated Biological Control System At Hanford

    International Nuclear Information System (INIS)

    In 1999 an integrated biological control system was instituted at the U.S. Department of Energy's Hanford Site. Successes and changes to the program needed to be communicated to a large and diverse mix of organizations and individuals. Efforts at communication are directed toward the following: Hanford Contractors (Liquid or Tank Waste, Solid Waste, Environmental Restoration, Science and Technology, Site Infrastructure), General Hanford Employees, and Hanford Advisory Board (Native American Tribes, Environmental Groups, Local Citizens, Washington State and Oregon State regulatory agencies). Communication was done through direct interface meetings, individual communication, where appropriate, and broadly sharing program reports. The objectives of the communication efforts was to have the program well coordinated with Hanford contractors, and to have the program understood well enough that all stakeholders would have confidence in the work performed by the program to reduce or elimate spread of radioactive contamination by biotic vectors. Communication of successes and changes to an integrated biological control system instituted in 1999 at the Department of Energy's Hanford Site have required regular interfaces with not only a diverse group of Hanford contractors (i.e., those responsible for liquid or tank waste, solid wastes, environmental restoration, science and technology, and site infrastructure), and general Hanford employees, but also with a consortium of designated stake holders organized as the Hanford Advisory Board (i.e., Native American tribes, various environmental groups, local citizens, Washington state and Oregon regulatory agencies, etc.). Direct interface meetings, individual communication where appropriate, and transparency of the biological control program were the methods and outcome of this effort.

  4. Landscape structure and biological control in agroecosystems

    Science.gov (United States)

    Thies; Tscharntke

    1999-08-01

    Biological pest control has primarily relied on local improvements in populations of natural enemies, but landscape structure may also be important. This is shown here with experiments at different spatial scales using the rape pollen beetle (Meligethes aeneus), an important pest on oilseed rape (Brassica napus). The presence of old field margin strips along rape fields was associated with increased mortality of pollen beetles resulting from parasitism and adjacent, large, old fallow habitats had an even greater effect. In structurally complex landscapes, parasitism was higher and crop damage was lower than in simple landscapes with a high percentage of agricultural use. PMID:10436158

  5. Rotating Biological Contractors (RBC's). Instructor's Guide. Biological Treatment Process Control.

    Science.gov (United States)

    Zickefoose, Charles S.

    This two-lesson unit on rotating biological contactors (RBC's) is designed to be used with students who have had some experience in wastewater treatment and a basic understanding of biological treatment. The first lesson provides information on the concepts and components of RBC treatment systems. The second lesson focuses on design operation and…

  6. Chemical Biology Strategies for Biofilm Control.

    Science.gov (United States)

    Yang, Liang; Givskov, Michael

    2015-08-01

    Microbes live as densely populated multicellular surface-attached biofilm communities embedded in self-generated, extracellular polymeric substances (EPSs). EPSs serve as a scaffold for cross-linking biofilm cells and support development of biofilm architecture and functions. Biofilms can have a clear negative impact on humans, where biofilms are a common denominator in many chronic diseases in which they prime development of destructive inflammatory conditions and the failure of our immune system to efficiently cope with them. Our current assortment of antimicrobial agents cannot efficiently eradicate biofilms. For industrial applications, the removal of biofilms within production machinery in the paper and hygienic food packaging industry, cooling water circuits, and drinking water manufacturing systems can be critical for the safety and efficacy of those processes. Biofilm formation is a dynamic process that involves microbial cell migration, cell-to-cell signaling and interactions, EPS synthesis, and cell-EPS interactions. Recent progress of fundamental biofilm research has shed light on novel chemical biology strategies for biofilm control. In this article, chemical biology strategies targeting the bacterial intercellular and intracellular signaling pathways will be discussed.

  7. Using Pseudomonas spp. for Integrated Biological Control.

    Science.gov (United States)

    Stockwell, Virginia O; Stack, James P

    2007-02-01

    ABSTRACT Pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. Currently, there are three commercial formulations of pseudomonads registered with the U.S. Environmental Protection Agency for plant disease suppression, Bio-Save 10 LP, Bio-Save 11 LP, and BlightBan A506. Bio-Save 10 LP and Bio-Save 11 LP, products of Jet Harvest Solutions, Longwood, FL, contain Pseudomonas syringae strains ESC-10 and ESC-11, respectively. These products are applied in packinghouses to prevent postharvest fungal diseases during storage of citrus, pome, stone fruits, and potatoes. BlightBan A506, produced by NuFarm Americas, Burr Ridge, IL, contains P. fluorescens strain A506. BlightBan A506 is applied primarily to pear and apple trees during bloom to suppress the bacterial disease fire blight. Combining BlightBan A506 with the antibiotic streptomycin improves control of fire blight, even in areas with streptomycin-resistant populations of the pathogen. BlightBan A506 also may reduce fruit russet and mild frost injury. These biocontrol products consisting of Pseudomonas spp. provide moderate to excellent efficacy against multiple production constraints, are relatively easy to apply, and they can be integrated with conventional products for disease control. These characteristics will contribute to the adoption of these products by growers and packinghouses. PMID:18944382

  8. Rotating Biological Contactors (RBC's). Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Zickefoose, Charles S.

    This student manual provides the textual material for a unit on rotating biological contactors (RBC's). Topic areas considered include: (1) flow patterns of water through RBC installations; (2) basic concepts (shaft and stage); (3) characteristics of biomass; (4) mechanical features (bearings, mechanical drive systems, and air drive systems); (5)…

  9. BIOLOGICAL CONTROL OF WEEDS BY MEANS OF PLANT PATHOGENS

    Directory of Open Access Journals (Sweden)

    Marija Ravlić

    2014-06-01

    Full Text Available Biological control is the use of live beneficial organisms and products of their metabolism in the pests control. Plant pathogens can be used for weed control in three different ways: as classical, conservation and augmentative (inoculative and inundated biological control. Inundated biological control involves the use of bioherbicides (mycoherbicides or artificial breeding of pathogens and application in specific stages of crops and weeds. Biological control of weeds can be used where chemical herbicides are not allowed, if resistant weed species are present or in the integrated pest management against weeds with reduced herbicides doses and other non-chemical measures, but it has certain limitations and disadvantages.

  10. Ecological Compatibility of GM Crops and Biological Control

    Science.gov (United States)

    Insect-resistant and herbicide-tolerant genetically modified (GM) crops pervade many modern cropping systems, and present challenges and opportunities for developing biologically-based pest management programs. Interactions between biological control agents (insect predators, parasitoids, and pathog...

  11. Complexity, Analysis and Control of Singular Biological Systems

    CERN Document Server

    Zhang, Qingling; Zhang, Xue

    2012-01-01

    Complexity, Analysis and Control of Singular Biological Systems follows the control of real-world biological systems at both ecological and phyisological levels concentrating on the application of now-extensively-investigated singular system theory. Much effort has recently been dedicated to the modelling and analysis of developing bioeconomic systems and the text establishes singular examples of these, showing how proper control can help to maintain sustainable economic development of biological resources. The book begins from the essentials of singular systems theory and bifurcations before tackling  the use of various forms of control in singular biological systems using examples including predator-prey relationships and viral vaccination and quarantine control. Researchers and graduate students studying the control of complex biological systems are shown how a variety of methods can be brought to bear and practitioners working with the economics of biological systems and their control will also find the ...

  12. Maternal feeding controls fetal biological clock.

    Directory of Open Access Journals (Sweden)

    Hidenobu Ohta

    Full Text Available BACKGROUND: It is widely accepted that circadian physiological rhythms of the fetus are affected by oscillators in the maternal brain that are coupled to the environmental light-dark (LD cycle. METHODOLOGY/PRINCIPAL FINDINGS: To study the link between fetal and maternal biological clocks, we investigated the effects of cycles of maternal food availability on the rhythms of Per1 gene expression in the fetal suprachiasmatic nucleus (SCN and liver using a transgenic rat model whose tissues express luciferase in vitro. Although the maternal SCN remained phase-locked to the LD cycle, maternal restricted feeding phase-advanced the fetal SCN and liver by 5 and 7 hours respectively within the 22-day pregnancy. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that maternal feeding entrains the fetal SCN and liver independently of both the maternal SCN and the LD cycle. This indicates that maternal-feeding signals can be more influential for the fetal SCN and particular organ oscillators than hormonal signals controlled by the maternal SCN, suggesting the importance of a regular maternal feeding schedule for appropriate fetal molecular clockwork during pregnancy.

  13. Nanostructure Control of Biologically Inspired Polymers

    Science.gov (United States)

    Rosales, Adrianne Marie

    Biological polymers, such as polypeptides, are responsible for many of life's most sophisticated functions due to precisely evolved hierarchical structures. These protein structures are the result of monodisperse sequences of amino acids that fold into well-defined chain shapes and tertiary structures. Recently, there has been much interest in the design of such sequence-specific polymers for materials applications in fields ranging from biotechnology to separations membranes. Non-natural polymers offer the stability and robustness necessary for materials applications; however, our ability to control monomer sequence in non-natural polymers has traditionally operated on a much simpler level. In addition, the relationship between monomer sequence and self-assembly is not well understood for biological molecules, much less synthetic polymers. Thus, there is a need to explore self-assembly phase space with sequence using a model system. Polypeptoids are non-natural, sequence-specific polymers that offer the opportunity to probe the effect of sequence on self-assembly. A variety of monomer interactions have an impact on polymer properties, such as chirality, hydrophobicity, and electrostatic interactions. Thus, a necessary starting point for this project was to investigate monomer sequence effects on the bulk properties of polypeptoid homopolymers. It was found that several polypeptoids have experimentally accessible melting transitions that are dependent on the choice of side chains, and it was shown that this transition is tuned by the incorporation of "defects" or a comonomer. The polypeptoid chain shape is also controlled with the choice of monomer and monomer sequence. By using at least 50% monomers with bulky, chiral side chains, the polypeptoid backbone is sterically twisted into a helix, and as found for the first time in this work, the persistence length is increased. However, this persistence length, which is a measure of the stiffness of the polymer, is

  14. Will the Convention on Biological Diversity put an end to biological control?

    Directory of Open Access Journals (Sweden)

    Joop C. van Lenteren

    2011-03-01

    Full Text Available Will the Convention on Biological Diversity put an end to biological control? Under the Convention on Biological Diversity countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties. This also applies to species collected for potential use in biological control. Recent applications of access and benefit sharing principles have already made it difficult or impossible to collect and export natural enemies for biological control research in several countries. If such an approach is widely applied it would impede this very successful and environmentally safe pest management method based on the use of biological diversity. The International Organization for Biological Control of Noxious Animals and Plants has, therefore, created the "Commission on Biological Control and Access and Benefit Sharing". This commission is carrying out national and international activities to make clear how a benefit sharing regime might seriously frustrate the future of biological control. In addition, the IOBC Commission members published information on current regulations and perceptions concerning exploration for natural enemies and drafted some 30 case studies selected to illustrate a variety of points relevant to access and benefit sharing. In this article, we summarize our concern about the effects of access and benefit sharing systems on the future of biological control.

  15. New Biologic Drug Tackles Hard-To-Control Asthma

    Science.gov (United States)

    ... html New Biologic Drug Tackles Hard-to-Control Asthma Benralizumab significantly cuts respiratory attacks, two trials show ... drug reduces flare-ups in patients with severe asthma that is not controlled by steroid inhalers alone, ...

  16. Parasitoids as biological control agents of thrips pests

    NARCIS (Netherlands)

    Loomans, A.J.M.

    2003-01-01

    Keywords: Thysanoptera, Frankliniella occidentalis, Hymenoptera, Ceranisus menes, Ceranisus americensis, biological controlThe thesis presented here is the result of a joint European Research project "Biological Control of Thrips Pests". Specific aims of the project were to collect, evaluate, mass p

  17. Biological control of the terrestrial carbon sink

    Directory of Open Access Journals (Sweden)

    E.-D. Schulze

    2006-01-01

    Full Text Available This lecture reviews the past (since 1964 when the International Biological Program began and the future of our understanding of terrestrial carbon fluxes with focus on photosynthesis, respiration, primary-, ecosystem-, and biome-productivity. Photosynthetic capacity is related to the nitrogen concentration of leaves, but the capacity is only rarely reached under field conditions. Average rates of photosynthesis and stomatal conductance are closely correlated and operate near 50% of their maximal rate, with light being the limiting factor in humid regions and air humidity and soil water the limiting factor in arid climates. Leaf area is the main factor to extrapolate from leaves to canopies, with maximum surface conductance being dependent on leaf level stomatal conductance. Additionally, gas exchange depends also on rooting depth which determines the water and nutrient availability and on mycorrhizae which regulate the nutrient status. An important anthropogenic disturbance is the nitrogen uptake from air pollutants, which is not balanced by cation uptake from roots and this may lead to damage and breakdown of the plant cover. Photosynthesis is the main carbon input into ecosystems, but it alone does not represent the ecosystem carbon balance, which is determined by respiration of various kinds. Plant respiration and photosynthesis determine growth (net primary production and microbial respiration balances the net ecosystem flux. In a spruce forest, 30% of the assimilatory carbon gain is used for respiration of needles, 20% is used for respiration in stems. Soil respiration is about 50% the carbon gain, half of which is root respiration, half is microbial respiration. In addition, disturbances lead to carbon losses, where fire, harvest and grazing bypass the chain of respiration. In total, the carbon balance at the biome level is only about 1% of the photosynthetic carbon input, or may indeed become negative. The recent observed increase in

  18. Biology and control of Varroa destructor.

    Science.gov (United States)

    Rosenkranz, Peter; Aumeier, Pia; Ziegelmann, Bettina

    2010-01-01

    The ectoparasitic honey bee mite Varroa destructor was originally confined to the Eastern honey bee Apis cerana. After a shift to the new host Apis mellifera during the first half of the last century, the parasite dispersed world wide and is currently considered the major threat for apiculture. The damage caused by Varroosis is thought to be a crucial driver for the periodical colony losses in Europe and the USA and regular Varroa treatments are essential in these countries. Therefore, Varroa research not only deals with a fascinating host-parasite relationship but also has a responsibility to find sustainable solutions for the beekeeping. This review provides a survey of the current knowledge in the main fields of Varroa research including the biology of the mite, damage to the host, host tolerance, tolerance breeding and Varroa treatment. We first present a general view on the functional morphology and on the biology of the Varroa mite with special emphasis on host-parasite interactions during reproduction of the female mite. The pathology section describes host damage at the individual and colony level including the problem of transmission of secondary infections by the mite. Knowledge of both the biology and the pathology of Varroa mites is essential for understanding possible tolerance mechanisms in the honey bee host. We comment on the few examples of natural tolerance in A. mellifera and evaluate recent approaches to the selection of Varroa tolerant honey bees. Finally, an extensive listing and critical evaluation of chemical and biological methods of Varroa treatments is given. This compilation of present-day knowledge on Varroa honey bee interactions emphasizes that we are still far from a solution for Varroa infestation and that, therefore, further research on mite biology, tolerance breeding, and Varroa treatment is urgently needed.

  19. Statistical properties and robustness of biological controller-target networks.

    Directory of Open Access Journals (Sweden)

    Jacob D Feala

    Full Text Available Cells are regulated by networks of controllers having many targets, and targets affected by many controllers, in a "many-to-many" control structure. Here we study several of these bipartite (two-layer networks. We analyze both naturally occurring biological networks (composed of transcription factors controlling genes, microRNAs controlling mRNA transcripts, and protein kinases controlling protein substrates and a drug-target network composed of kinase inhibitors and of their kinase targets. Certain statistical properties of these biological bipartite structures seem universal across systems and species, suggesting the existence of common control strategies in biology. The number of controllers is ∼8% of targets and the density of links is 2.5%±1.2%. Links per node are predominantly exponentially distributed. We explain the conservation of the mean number of incoming links per target using a mathematical model of control networks, which also indicates that the "many-to-many" structure of biological control has properties of efficient robustness. The drug-target network has many statistical properties similar to the biological networks and we show that drug-target networks with biomimetic features can be obtained. These findings suggest a completely new approach to pharmacological control of biological systems. Molecular tools, such as kinase inhibitors, are now available to test if therapeutic combinations may benefit from being designed with biomimetic properties, such as "many-to-many" targeting, very wide coverage of the target set, and redundancy of incoming links per target.

  20. Encyrtid parasitoids of soft scale insects: biology, behavior, and their use in biological control.

    Science.gov (United States)

    Kapranas, Apostolos; Tena, Alejandro

    2015-01-01

    Parasitoids of the hymenopterous family Encyrtidae are one of the most important groups of natural enemies of soft scale insects and have been used extensively in biological control. We summarize existing knowledge of the biology, ecology, and behavior of these parasitoids and how it relates to biological control. Soft scale stage/size and phenology are important determinants of host range and host utilization, which are key aspects in understanding how control by these parasitoids is exerted. Furthermore, the nutritional ecology of encyrtids and their physiological interactions with their hosts affect soft scale insect population dynamics. Lastly, the interactions among encyrtids, heteronomous parasitoids, and ants shape parasitoid species complexes and consequently have a direct impact on the biological control of soft scale insects.

  1. Crop association to improve aphid biological control

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bosquée, Emilie; Bodson, Bernard; Francis, Frédéric

    2014-01-01

    This research focused on the development of sustainable alternative methods to control aphids, giving special emphasis on cultural practices and plant management systems. Increasing the diversity within crops may have several beneficial effects on pest control, creating attractive habitats for indigenous beneficial fauna and simultaneously deterring pests (“push-pull” approach). In this field study, two wheat/pea associations (mixed cropping and strip cropping) where compared to monocultures ...

  2. Biological control of weeds release sites : Kulm Wetland Management District

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Table of release sites of insects for biological control of invasive plants at Kulm Wetland Management District (WMD). Insects were released on Kulm WMD to...

  3. Arms Control: US and International efforts to ban biological weapons

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    The Bacteriological (Biological) and Toxin Weapons Convention, the treaty that bans the development, production, and stockpiling and acquisition of biological weapons was opened for signature in 1972 and came into force in 1975 after being ratified by 22 governments, including the depository nations of the USA, the United Kingdom, and the former Soviet Union. In support of the Convention, the USA later established export controls on items used to make biological weapons. Further, in accordance with the 1990 President`s Enhanced Proliferation Control Initiative, actions were taken to redefine and expand US export controls, as well as to encourage multilateral controls through the Australia Group. Thus far, the Convention has not been effective in stopping the development of biological weapons. The principal findings as to the reasons of the failures of the Convention are found to be: the Convention lacks universality, compliance measures are effective, advantage of verification may outweigh disadvantages. Recommendations for mitigating these failures are outlined in this report.

  4. Identification and evaluation of Trichogramma parasitoids for biological pest control

    OpenAIRE

    Silva, I.M.M.S.

    1999-01-01

    Egg parasitoids of the genus Trichogramma are used as biological control agents against lepidopterous pests. From the 180 species described world-wide, only 5 have large scale application. The development of better methods to select other Trichogramma species/strains is necessary for a more effective use of these wasps against target pests. The main aim of this thesis is to investigate criteria and methods for identification and selection of Trichogramma species/strains for biological control...

  5. Biological control of tortricids and aphids in strawberries

    DEFF Research Database (Denmark)

    Sigsgaard, Lene; Enkegaard, Annie; Eilenberg, Jørgen;

    Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising.......Cropping practice and biological control can contribute to reduced pesticide use in strawberries. Organic strawberries are less attacked by strawberry tortricid and buckwheat flower strips can augment its natural enemies. Against shallot aphid the two-spot ladybird is promising....

  6. Controllability and observability of Boolean networks arising from biology.

    Science.gov (United States)

    Li, Rui; Yang, Meng; Chu, Tianguang

    2015-02-01

    Boolean networks are currently receiving considerable attention as a computational scheme for system level analysis and modeling of biological systems. Studying control-related problems in Boolean networks may reveal new insights into the intrinsic control in complex biological systems and enable us to develop strategies for manipulating biological systems using exogenous inputs. This paper considers controllability and observability of Boolean biological networks. We propose a new approach, which draws from the rich theory of symbolic computation, to solve the problems. Consequently, simple necessary and sufficient conditions for reachability, controllability, and observability are obtained, and algorithmic tests for controllability and observability which are based on the Gröbner basis method are presented. As practical applications, we apply the proposed approach to several different biological systems, namely, the mammalian cell-cycle network, the T-cell activation network, the large granular lymphocyte survival signaling network, and the Drosophila segment polarity network, gaining novel insights into the control and/or monitoring of the specific biological systems.

  7. Controllability and observability of Boolean networks arising from biology

    Science.gov (United States)

    Li, Rui; Yang, Meng; Chu, Tianguang

    2015-02-01

    Boolean networks are currently receiving considerable attention as a computational scheme for system level analysis and modeling of biological systems. Studying control-related problems in Boolean networks may reveal new insights into the intrinsic control in complex biological systems and enable us to develop strategies for manipulating biological systems using exogenous inputs. This paper considers controllability and observability of Boolean biological networks. We propose a new approach, which draws from the rich theory of symbolic computation, to solve the problems. Consequently, simple necessary and sufficient conditions for reachability, controllability, and observability are obtained, and algorithmic tests for controllability and observability which are based on the Gröbner basis method are presented. As practical applications, we apply the proposed approach to several different biological systems, namely, the mammalian cell-cycle network, the T-cell activation network, the large granular lymphocyte survival signaling network, and the Drosophila segment polarity network, gaining novel insights into the control and/or monitoring of the specific biological systems.

  8. Biological effect of penetration controlled irradiation with ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi; Shimizu, Takashi; Kikuchi, Masahiro; Kobayashi, Yasuhiko; Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Yamashita, Takao

    1997-03-01

    To investigate the effect of local irradiation with ion beams on biological systems, technique for penetration controlled irradiation has been established. The range in a target was controlled by changing the distance from beam window in the atmosphere, and could be controlled linearly up to about 31 {mu}m in biological material. In addition, the effects of the penetration controlled irradiations with 1.5 MeV/u C and He ions were examined using tobacco pollen. The increased frequency of leaky pollen produced by ion beams suggests that the efficient pollen envelope damages would be induced at the range-end of ion beams. (author)

  9. Anti-tick biological control agents: assessment and future perspectives

    Science.gov (United States)

    Samish, M., H.; Ginsberg, H.S.; Glazer, I.

    2008-01-01

    Widespread and increasing resistance to most available acaracides threatens both global livestock industries and public health. This necessitates better understanding of ticks and the diseases they transmit in the development of new control strategies. Ticks: Biology, Disease and Control is written by an international collection of experts and covers in-depth information on aspects of the biology of the ticks themselves, various veterinary and medical tick-borne pathogens, and aspects of traditional and potential new control methods. A valuable resource for graduate students, academic researchers and professionals, the book covers the whole gamut of ticks and tick-borne diseases from microsatellites to satellite imagery and from exploiting tick saliva for therapeutic drugs to developing drugs to control tick populations. It encompasses the variety of interconnected fields impinging on the economically important and biologically fascinating phenomenon of ticks, the diseases they transmit and methods of their control.

  10. Exogenous control of biological and ecological systems through evolutionary modelling

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2013-09-01

    Full Text Available The controllability of network-like systems is a topical issue in ecology and biology. It relies on the ability to lead a system's behaviour towards the desired state through the appropriate handling of input variables. Up to now, controllability of networks is based on the permanent control of a set of driver nodes that can guide the system's dynamics. This assumption seems motivated by real-world networks observation, where a decentralized control is often applied only to part of the nodes. While in a previous paper I showed that ecological and biological networks can be efficaciously controlled from the inside, here I further introduce a new framework for network controllability based on the employment of exogenous controllers and evolutionary modelling, and provide an exemplification of its application.

  11. Augmentative biological control of arthropods in Latin America

    NARCIS (Netherlands)

    Lenteren, van J.C.; Bueno, V.H.P.

    2003-01-01

    Augmentative forms of biological control, where natural enemies are periodically introduced, are applied over large areas in various cropping systems in Latin America. About 25% of the world area under augmentative control is situated in this region. Well-known examples are the use of species of the

  12. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  13. Citrus growers vary in their adoption of biological control

    OpenAIRE

    Grogan, Kelly A.; Goodhue, Rachael E

    2012-01-01

    In a spring 2010 survey, we investigated the characteristics that influenced whether California growers controlled major citrus pests with beneficial insects. We also performed statistical analysis of growers' reliance on Aphytus melinus, a predatory wasp, to control California red scale. The survey results suggest that growers with greater citrus acreage and more education are more likely to use biological control. Marketing outlets, ethnicity and primary information sources also influenced ...

  14. Conservation biological control and enemy diversity on a landscape scale

    NARCIS (Netherlands)

    Tscharntke, T.; Bommarco, R.; Clough, Y.; Crist, T.O.; Kleijn, D.; Rand, T.A.; Tylianakis, J.M.; Nouhuys, S.; Vidal, S.

    2007-01-01

    Conservation biological control in agroecosystems requires a landscape management perspective, because most arthropod species experience their habitat at spatial scales beyond the plot level, and there is spillover of natural enemies across the crop–noncrop interface. The species pool in the surroun

  15. Identification and evaluation of Trichogramma parasitoids for biological pest control

    NARCIS (Netherlands)

    Silva, I.M.M.S.

    1999-01-01

    Egg parasitoids of the genus Trichogramma are used as biological control agents against lepidopterous pests. From the 180 species described world-wide, only 5 have large scale application. The development of better methods to select other Trichogramma species/strains is necessary for a more effectiv

  16. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation

    OpenAIRE

    Tautorus, T. E.; Townsley, P. M.

    1983-01-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus no...

  17. Adaptive Fuzzy-Lyapunov Controller Using Biologically Inspired Swarm Intelligence

    OpenAIRE

    Alejandro Carrasco Elizalde; Peter Goldsmith

    2008-01-01

    The collective behaviour of swarms produces smarter actions than those achieved by a single individual. Colonies of ants, flocks of birds and fish schools are examples of swarms interacting with their environment to achieve a common goal. This cooperative biological intelligence is the inspiration for an adaptive fuzzy controller developed in this paper. Swarm intelligence is used to adjust the parameters of the membership functions used in the adaptive fuzzy controller. The rules of the cont...

  18. Evaluation of Orius species for biological control of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

    NARCIS (Netherlands)

    Tommasini, M.G.

    2003-01-01

    Key words: Thysanoptera, Frankliniella occidentalis, Heteroptera, Orius leavigatu, Orius majusculu, Orius niger, Orius insidiosus, Biology, Diapause, Biological control.The overall aim of this research was to develop a biological control programme for F. occidentalis through the selection of

  19. Biologically controlled minerals as potential indicators of life

    Science.gov (United States)

    Schwartz, D. E.; Mancinelli, R. L.; Kaneshiro, E.

    1991-01-01

    Minerals can be produced and deposited either by abiotic or biologic means. Regardless of their origin, mineral crystals reflect the environment conditions (e.g., temperature, pressure, chemical composition, and redox potential) present during crystal formation. Biologically-produced mineral crystals are grown or reworked under the control of their host organism and reflect an environment different from the abiotic environment. In addition, minerals of either biologic or abiotic origin have great longevities. For these reasons, biologically produced minerals have been proposed as biomarkers. Biomarkers are key morphological, chemical, and isotopic signatures of living systems that can be used to determine if life processes have occurred. Studies of biologically controlled minerals produced by the protist, Paramecium tetraurelia, were initiated since techniques have already been developed to culture them and isolate their crystalline material, and methods are already in place to analyze this material. Two direct crystalline phases were identified. One phase, whose chemical composition is high in Mg, was identified as struvite. The second phase, whose chemical composition is high in Ca, has not been previously found occurring naturally and may be considered a newly discovered material. Analyses are underway to determine the characteristics of these minerals in order to compare them with characteristics of these minerals in order to compare them with characteristics of minerals formed abiotically, but with the same chemical composition.

  20. Epigenetics and Why Biological Networks are More Controllable than Expected

    Science.gov (United States)

    Motter, Adilson

    2013-03-01

    A fundamental property of networks is that perturbations to one node can affect other nodes, potentially causing the entire system to change behavior or fail. In this talk, I will show that it is possible to exploit this same principle to control network behavior. This approach takes advantage of the nonlinear dynamics inherent to real networks, and allows bringing the system to a desired target state even when this state is not directly accessible or the linear counterpart is not controllable. Applications show that this framework permits both reprogramming a network to a desired task as well as rescuing networks from the brink of failure, which I will illustrate through various biological problems. I will also briefly review the progress our group has made over the past 5 years on related control of complex networks in non-biological domains.

  1. A theoretical approach on controlling agricultural pest by biological controls.

    Science.gov (United States)

    Mondal, Prasanta Kumar; Jana, Soovoojeet; Kar, T K

    2014-03-01

    In this paper we propose and analyze a prey-predator type dynamical system for pest control where prey population is treated as the pest. We consider two classes for the pest namely susceptible pest and infected pest and the predator population is the natural enemy of the pest. We also consider average delay for both the predation rate i.e. predation to the susceptible pest and infected pest. Considering a subsystem of original system in the absence of infection, we analyze the existence of all possible non-negative equilibria and their stability criteria for both the subsystem as well as the original system. We present the conditions for transcritical bifurcation and Hopf bifurcation in the disease free system. The theoretical evaluations are demonstrated through numerical simulations.

  2. Controlled biological and biomimetic systems for landmine detection.

    Science.gov (United States)

    Habib, Maki K

    2007-08-30

    Humanitarian demining requires to accurately detect, locate and deactivate every single landmine and other buried mine-like objects as safely and as quickly as possible, and in the most non-invasive manner. The quality of landmine detection affects directly the efficiency and safety of this process. Most of the available methods to detect explosives and landmines are limited by their sensitivity and/or operational complexities. All landmines leak with time small amounts of their explosives that can be found on surrounding ground and plant life. Hence, explosive signatures represent the robust primary indicator of landmines. Accordingly, developing innovative technologies and efficient techniques to identify in real-time explosives residue in mined areas represents an attractive and promising approach. Biological and biologically inspired detection technology has the potential to compete with or be used in conjunction with other artificial technology to complement performance strengths. Biological systems are sensitive to many different scents concurrently, a property that has proven difficult to replicate artificially. Understanding biological systems presents unique opportunities for developing new capabilities through direct use of trained bio-systems, integration of living and non-living components, or inspiring new design by mimicking biological capabilities. It is expected that controlled bio-systems, biotechnology and microbial techniques will contribute to the advancement of mine detection and other application domains. This paper provides directions, evaluation and analysis on the progress of controlled biological and biomimetic systems for landmine detection. It introduces and discusses different approaches developed, underlining their relative advantages and limitations, and highlighting trends, safety and ecology concern, and possible future directions. PMID:17662594

  3. Wolbachia: A biological control strategy against arboviral diseases.

    Science.gov (United States)

    Mohanty, Ipsita; Rath, Animesha; Mahapatra, Namita; Hazra, Rupenangshu K

    2016-01-01

    Vector-borne diseases particularly those transmitted by mosquitoes like Dengue are among the leading causes of mortality and morbidity in human population. There are no effective vaccines or treatment against dengue fever till date and the control methods are limited. So, new approaches are urgently in need to reverse these trends. Vector control is currently the primary intervention tool. Strategies that reduce or block pathogen transmission by mosquitoes have been proposed as a means of augmenting current control measures to reduce the growing burden of vector-borne diseases. Wolbachia an endosymbiont of arthropod vectors is being explored as a novel ecofriendly control strategy. Studies in Drosophila have shown that Wolbachia can confer resistance to diverse RNA viruses and protect flies from virus-induced mortality. This review was focused on biology of the Wolbachia and its implication as a control measure for arboviral diseases mainly Dengue and Chikungunya. PMID:27681542

  4. Biological control of water hyacinth on Lake Victoria, Kenya.

    OpenAIRE

    Ochiel, G.R.S.; Mailu, A.M.; Gitonga, W.; Njoka, S.W.

    1998-01-01

    The Kenya Agricultural Research Institute (KARI) imported 12 800 curculionid weevils (Neochetina spp.) from Benin, Uganda, South Africa and Australia for biological control of water hyacinth between 1993 and1998. In 1996, KARI’s rearing and quarantine facility at the National Agricultural Research Centre, Muguga, provided initial “breeding stock” to another rearing facility at the National Fibre Research Centre, Kibos, near Lake Victoria. To date, 36 500 weevils and 42 000 w...

  5. Biopesticides: An option for the biological pest control

    OpenAIRE

    Eusebio Nava Pérez; Cipriano García Gutiérrez; Jesús Ricardo Camacho Báez; Elva Lorena Vázquez Montoya

    2012-01-01

    The indiscriminate use of synthetic pesticides and the problems that its cause to human health, agriculture and the environment is comment, this paper also present general aspects about of biopesticides, and their uses in the biological pest control. By the nature these can be safely used in a sustainable agriculture. An example is the use of botanical pesticides whose active ingredient are the terpenes, alkaloids and phenolics, these have insecticide effects for many agriculture pests; also...

  6. Evolution in invasive plants: implications for biological control

    OpenAIRE

    Müller-Schärer, Heinz; Schaffner, Urs; Steinger, Thomas

    2005-01-01

    Evidence is increasing that invasive plants can undergo rapid adaptive evolution during the process of range expansion. Here, we argue that evolutionary change during invasions will also affect plant–antagonist inter-actions and, thus, will have important implications for biological control programmes targeted at invasive plants. We explore how altered selection in the new range might influence the evolution of plant defence (resistance and tolerance) and life history. The degree to which suc...

  7. Biological control of Fusarium graminearum on wheat by antagonistic bacteria

    OpenAIRE

    Javad Nourozian; Hassan Reza Etebarian; Gholam Khodakaramian

    2006-01-01

    Bacillus subtilis strains 53 and 71, Pseudomonas fluorescens biov1 strain 32 and Streptomyces sp. Strain 3 were evaluated as potential biological agents for control of fusarium head blight (FHB) caused by Fusarium graminearum. Mycelial growth of the pathogen was reduced by cell free and volatile metabolites of bacterial antagonists by 37%-97%. Streptomyces sp. Strain 3 reduced disease severity of FHB 21 d after inoculation. The yield of wheat from plants treated with Streptomyces sp. strain 3...

  8. Leaf microbiota of strawberries as affected by biological control agents

    OpenAIRE

    Sylla, Justine; Alsanius, Beatrix W; Krüger, Erika; Reineke, Annette; Strohmeier, Stephan; Wohanka, Walter

    2013-01-01

    The increasing use of biological control agents (BCAs) against Botrytis cinerea in strawberry raises the question of whether there are any undesirable impacts of foliar applications of BCAs on nontarget microorganisms in the phyllosphere. Therefore, our objective was to investigate this issue within a field study. Strawberry plants were repeatedly sprayed with three BCAs—namely, RhizoVital 42 fl. (Bacillus amyloliquefaciens FZB42), Trianum-P (Trichoderma harzianum T22), and Naturalis (Beauver...

  9. Goatsrue (Galega officinalis) Seed Biology, Control, and Toxicity

    OpenAIRE

    Oldham, Michelle

    2009-01-01

    Goatsrue is an introduced perennial plant that has proven to have great invasive potential, leading to its classification as a noxious weed in many states and at the federal level. This research focused on seed biology, herbicide control, and toxic dynamics of goatsrue. Physical dormancy of mature goatsrue seed was tested through scarification using sulfuric acid with exposures of up to 60 minutes resulting in 100% germination. Comparison of dormancy for 26-year-old and 6-month-old goatsru...

  10. Biological Control of Olive Green Mold in Agaricus bisporus Cultivation.

    Science.gov (United States)

    Tautorus, T E; Townsley, P M

    1983-02-01

    Successful methods to control the damaging weed mold Chaetomium olivaceum (olive green mold) in mushroom beds are not presently known. An attempt was made to control C. olivaceum by biological means. A thermophilic Bacillus sp. which showed dramatic activity against C. olivaceum on Trypticase soy agar (BBL Microbiology Systems)-0.4% yeast extract agar plates was isolated from commercial mushroom compost (phase I). When inoculated into conventional and hydroponic mushroom beds, the bacillus not only provided a significant degree of protection from C. olivaceum, but also increased yields of Agaricus bisporus.

  11. Self-Organized Biological Dynamics and Nonlinear Control

    Science.gov (United States)

    Walleczek, Jan

    2006-04-01

    The frontiers and challenges of biodynamics research Jan Walleczek; Part I. Nonlinear Dynamics in Biology and Response to Stimuli: 1. External signals and internal oscillation dynamics - principal aspects and response of stimulated rhythmic processes Friedemann Kaiser; 2. Nonlinear dynamics in biochemical and biophysical systems: from enzyme kinetics to epilepsy Raima Larter, Robert Worth and Brent Speelman; 3. Fractal mechanisms in neural control: human heartbeat and gait dynamics in health and disease Chung-Kang Peng, Jeffrey M. Hausdorff and Ary L. Goldberger; 4. Self-organising dynamics in human coordination and perception Mingzhou Ding, Yanqing Chen, J. A. Scott Kelso and Betty Tuller; 5. Signal processing in biochemical reaction networks Adam P. Arkin; Part II. Nonlinear Sensitivity of Biological Systems to Electromagnetic Stimuli: 6. Electrical signal detection and noise in systems with long-range coherence Paul C. Gailey; 7. Oscillatory signals in migrating neutrophils: effects of time-varying chemical and electrical fields Howard R. Petty; 8. Enzyme kinetics and nonlinear biochemical amplification in response to static and oscillating magnetic fields Jan Walleczek and Clemens F. Eichwald; 9. Magnetic field sensitivity in the hippocampus Stefan Engström, Suzanne Bawin and W. Ross Adey; Part III. Stochastic Noise-Induced Dynamics and Transport in Biological Systems: 10. Stochastic resonance: looking forward Frank Moss; 11. Stochastic resonance and small-amplitude signal transduction in voltage-gated ion channels Sergey M. Bezrukov and Igor Vodyanoy; 12. Ratchets, rectifiers and demons: the constructive role of noise in free energy and signal transduction R. Dean Astumian; 13. Cellular transduction of periodic and stochastic energy signals by electroconformational coupling Tian Y. Tsong; Part IV. Nonlinear Control of Biological and Other Excitable Systems: 14. Controlling chaos in dynamical systems Kenneth Showalter; 15. Electromagnetic fields and biological

  12. Adaptive Fuzzy-Lyapunov Controller Using Biologically Inspired Swarm Intelligence

    Directory of Open Access Journals (Sweden)

    Alejandro Carrasco Elizalde

    2008-01-01

    Full Text Available The collective behaviour of swarms produces smarter actions than those achieved by a single individual. Colonies of ants, flocks of birds and fish schools are examples of swarms interacting with their environment to achieve a common goal. This cooperative biological intelligence is the inspiration for an adaptive fuzzy controller developed in this paper. Swarm intelligence is used to adjust the parameters of the membership functions used in the adaptive fuzzy controller. The rules of the controller are designed using a computing-with-words approach called Fuzzy-Lyapunov synthesis to improve the stability and robustness of an adaptive fuzzy controller. Computing-with-words provides a powerful tool to manipulate numbers and symbols, like words in a natural language.

  13. Biopesticides: An option for the biological pest control

    Directory of Open Access Journals (Sweden)

    Eusebio Nava Pérez

    2012-09-01

    Full Text Available The indiscriminate use of synthetic pesticides and the problems that its cause to human health, agriculture and the environment is comment, this paper also present general aspects about of biopesticides, and their uses in the biological pest control. By the nature these can be safely used in a sustainable agriculture. An example is the use of botanical pesticides whose active ingredient are the terpenes, alkaloids and phenolics, these have insecticide effects for many agriculture pests; also its are less expensive, are biodegradable and safe for humans and the environment, however havelittle residuality. Microbial pesticides are being introduced successfully to pests control in important crops such as; coffee, sugar cane, beans and corn. These products contain bacteria, fungi, viruses or nematodes. However, few entomopathogenic agents have been developed as effective biocontrol agents, one of them is the bacterium Bacillus thuringiensis (Berlinier for control of armyworm Spodoptera frugiperda (J.E Smith covering about 74% of the market,fungus 10% , viruses 5% and 11% others. Other upstanding case is the use of the fungus Beauveria bassiana (Balsamoagainst bean weevil Acanthoscelides obtectus (Say. Biopesticides have shown that when are used properly in the biological pest control its favor the practice of a sustainable agriculture, with less dependence of chemical insecticides.

  14. Biologically Inspired Robotic Arm Control Using an Artificial Neural Oscillator

    Directory of Open Access Journals (Sweden)

    Woosung Yang

    2010-01-01

    Full Text Available We address a neural-oscillator-based control scheme to achieve biologically inspired motion generation. In general, it is known that humans or animals exhibit novel adaptive behaviors regardless of their kinematic configurations against unexpected disturbances or environment changes. This is caused by the entrainment property of the neural oscillator which plays a key role to adapt their nervous system to the natural frequency of the interacted environments. Thus we focus on a self-adapting robot arm control to attain natural adaptive motions as a controller employing neural oscillators. To demonstrate the excellence of entrainment, we implement the proposed control scheme to a single pendulum coupled with the neural oscillator in simulation and experiment. Then this work shows the performance of the robot arm coupled to neural oscillators through various tasks that the arm traces a trajectory. With these, the real-time closed-loop system allowing sensory feedback of the neural oscillator for the entrainment property is proposed. In particular, we verify an impressive capability of biologically inspired self-adaptation behaviors that enables the robot arm to make adaptive motions corresponding to an unexpected environmental variety.

  15. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  16. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  17. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  18. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  19. Study on Biological Control Of Rhizoctonia solani via Trichoderma

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Strain T02-25 was selected from approximately 30 rhizosphere isolates of Trichoderma species isolated from roots of crops. Its biological activity against Rhizoctonia solani was determined for the control efficacy to pepper seedling blight caused by R. solani in the field. The assay methods were treating R. solani sclerotia by Trichoderma conidial suspension (106cfu ml-1) and scattering Thichoderma rice bran over the pepper root medium. The results showed that T02-25 was active against R. solani in both ways, and its control efficacy was 82.7% and 78.0%, respectively. In addition to comparison of the efficacy of the two application methods, the relationship of different factors in the control efficacy of Trichoderma against R. solani was discussed.

  20. Indoor biology pollution control based on system-based humidity priority control strategy

    Institute of Scientific and Technical Information of China (English)

    刘亚昱; 谢慧; 石博强

    2009-01-01

    Indoor biological contamination and HVAC system secondary contamination problems caused wide public concerns. Biological contamination control will be the next step to achieve better IAQ. The most efficient and safe way to control biological contamination was to limit relative humidity in HVAC system and conditioned environment in the range that is more unsuitable for microorganism to survive. In this paper,by referring to bio-clean project experiences,a system-based humidity priority control manner came into being by lowering outdoor air humidity ratio to eliminate all indoor latent load and using self recirculation units to bear indoor sensible load. Based on the whole-course residue humidity contaminant control concept,dynamic step models for coil and conditioned zone were developed to describe mass and energy conservation and transformation processes. Then,HVAC system and conditioned zone dynamic models were established on LabVIEW+Matlab platform to investigate optimized regulation types,input signatures and control logics. Decoupling between cooling and dehumidification processes can be achieved and a more simplified and stable control system can be acquired by the system-based humidity priority control strategy. Therefore,it was a promising way for controlling biological pollution in buildings in order to achieve better IAQ.

  1. Biological Efficacy of Herbicides for Weed Control in Noncropped Areas

    Directory of Open Access Journals (Sweden)

    Tsvetanka Dimitrova

    2009-01-01

    Full Text Available An increasing problem facing agricultural producers is the invasion of weeds, perennial in particular, so that implementation of industrial technologies is impossible without their highly efficient and rational control. For the purpose of studying efficient herbicides for weed control in noncropped areas (stubbles, a biological study of five total systemic herbicides was conducted in areas under natural weed infestation and pressure from othersurrounding weeds at the Institute of Forage Crops in Pleven in 2005-2007. The trials were carried out in field conditions using the block method with plot size of 20 m². Treatment was conducted at the predominant stage of budding of perennial dicotyledonous weeds and earing of monocotyledonous weeds. Herbicidal efficacy was recorded on the EWRS 9-score scale (0-100% killed weeds = score 9-1. It was found that treatment of noncropped areas (stubbles with the total systemic herbicides Touchdown System 4 (360 g/l glyphosate; Cosmic (360 g/l glyphosate; Roundup Plus (441 g/l glyphosate potassium salt; Leon 36 SL (360 g/l glyphosate and Glyphos Super 45 SL (450 g/l glyphosate was highly efficient, so that it was a successful element of a strategy for controlling weeds of different biological groups, and was especially effective against perennial weeds.

  2. Microstructure synthesis control of biological polyhydroxyalkanoates with mass spectrometry

    Science.gov (United States)

    Pederson, Erik Norman

    Polyhydroxyalkanoates (PHA's) are a class of biologically produced polymers, or plastic, that is synthesized by various microorganisms. PHA's are made from biorenewable resources and are fully biodegradable and biocompatible, making them an environmentally friendly green polymer. A method of incorporating polymer microstructure into the PHA synthesized in Ralstonia eutropha was developed. These microstructures were synthesized with polyhydroxybutyrate (PHB) and poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) as the polymer domains. To synthesize the PHB V copolymer, the additional presence of valerate was required. To control valerate substrate additions to the bioreactor, an off-gas mass spectrometry (MS) feedback control system was developed. Important process information including the cell physiology, growth kinetics, and product formation kinetics in the bioreactor was obtained with MS and used to control microstructure synthesis. The two polymer microstructures synthesized were core-shell granules and block copolymers. Block copolymers control the structure of the individual polymer chains while core-shell granules control the organization of many polymer chains. Both these microstructures result in properties unattainable by blending the two polymers together. The core-shell structures were synthesized with controlled domain thickness based on a developed model. Different block copolymers compositions were synthesized by varying the switching time of the substrate pulses responsible for block copolymer synthesis. The block copolymers were tested to determine their chemical properties and cast into films to determine the materials properties. These block copolymer films possessed new properties not achieved by copolymers or blends of the two polymers.

  3. A biological model for controlling interface growth and morphology.

    Energy Technology Data Exchange (ETDEWEB)

    Hoyt, Jeffrey John; Holm, Elizabeth Ann

    2004-01-01

    Biological systems create proteins that perform tasks more efficiently and precisely than conventional chemicals. For example, many plants and animals produce proteins to control the freezing of water. Biological antifreeze proteins (AFPs) inhibit the solidification process, even below the freezing point. These molecules bond to specific sites at the ice/water interface and are theorized to suppress solidification chemically or geometrically. In this project, we investigated the theoretical and experimental data on AFPs and performed analyses to understand the unique physics of AFPs. The experimental literature was analyzed to determine chemical mechanisms and effects of protein bonding at ice surfaces, specifically thermodynamic freezing point depression, suppression of ice nucleation, decrease in dendrite growth kinetics, solute drag on the moving solid/liquid interface, and stearic pinning of the ice interface. Stearic pinning was found to be the most likely candidate to explain experimental results, including freezing point depression, growth morphologies, and thermal hysteresis. A new stearic pinning model was developed and applied to AFPs, with excellent quantitative results. Understanding biological antifreeze mechanisms could enable important medical and engineering applications, but considerable future work will be necessary.

  4. Biological Characteristics and Control of Orobanche Crenata Forsk., a Review

    Directory of Open Access Journals (Sweden)

    Giuseppe Restuccia

    2011-02-01

    Full Text Available Orobanche crenata is a holoparasitic phanerogam which is particularly noxious to legumes, such as faba bean (Vicia faba L., pea (Pisum sativum L., chickpea (Cicer arietinum L., lentil (Lens culinaris Medik., etc., and commonly considered one of the major causes which has contributed to re-rizing the area designed to their cultivation. After a few brief references on the origin and diffusion of O. crenata, in this work summarises the results of research into biological aspects and control of this species. The information obtained especially concerns seed production, seed viability, seed longevity and dormancy, seed conditioning and germination, parasitism phases, the effects of parasite attacks on host plants and the means of control.

  5. Control of Lymantria dispar L. by biological agents

    Institute of Scientific and Technical Information of China (English)

    ZHANGGuo-cai; WANGYue-jie; YANGXiao-guang

    2005-01-01

    The experiment on control of Lymantria dispar L by using different kinds of biological measures, including nuclear polyhedrosis virus (NPV) of Lymantria dispar L., BtMP-342, sex-attractant as well as botanical insecticide, was carried out in the forest regions of Inner Mongolia in 2003. Two concentrations (2.632×106 PIB·ml-1 and 2.632×107 PIB·ml-1) of Lymantria dispar L. NPV were sprayed on the 2rd-instar-larvae of L. dispar and 70% and 77.8% control effect were obtained respectively. BtMP0-342 was applied to the 3rd- and 4th-instar larvae and the control effect was around 80%. The sex-attractant provided by Canada Pacific Forestry Research Center also showed a good result in trapping L. dispar adults. The self-produced botanical insecticide, which was extracted from a kind of poisonous plant distributed in Daxing'an Mountains, China, exhibited a good control result in controlling the larvae of L. dispar, and 82% mortality was observed when spraying primary liquid of the botanical insecticide on the 3rd-5th-instar-larvae in lab.

  6. Reevaluation of the value of autoparasitoids in biological control.

    Directory of Open Access Journals (Sweden)

    Lian-Sheng Zang

    Full Text Available Autoparasitoids with the capacity of consuming primary parasitoids that share the same hosts to produce males are analogous to intraguild predators. The use of autoparasitoids in biological control programs is a controversial matter because there is little evidence to support the view that autoparasitoids do not disrupt and at times may promote suppression of insect pests in combination with primary parasitoids. We found that Encarsia sophia, a facultative autoparasitoid, preferred to use heterospecific hosts as secondary hosts for producing males. The autoparasitoids mated with males originated from heterospecifics may parasitize more hosts than those mated with males from conspecifics. Provided with an adequate number of males, the autoparasitoids killed more hosts than En. formosa, a commonly used parasitoid for biological control of whiteflies. This study supports the view that autoparasitoids in combination with primary parasitoids do not disrupt pest management and may enhance such programs. The demonstrated preference of an autoparasitoid for heterospecifics and improved performance of males from heterospecifics observed in this study suggests these criteria should be considered in strategies that endeavor to mass-produce and utilize autoparasitoids in the future.

  7. INTEGRATED MANAGEMENT OF CHROMOLAENA ODORATA EMPHASIZING THE CLASSICAL BIOLOGICAL CONTROL

    Directory of Open Access Journals (Sweden)

    SOEKISMAN TJITROSEMITO

    1998-01-01

    Full Text Available Chromolaena odorata, Siam weed, a very important weed of Java Island (Indonesia is native to Central and South America. In the laboratory it showed rapid growth (1.15 g/g/week in the first 8 weeks of its growth. The biomass was mainly as leaves (LAR : 317.50 cm'/g total weight. It slowed down in the following month as the biomass was utilized for stem and branch formation. This behavior supported the growth of C. odorata into a very dense stand. It flowered, fruited during the dry season, and senesced following maturation of seeds from inflorescence branches. These branches dried out, but soon the stem resumed aggressive growth following the wet season. Leaf biomass was affected by the size of the stem in its early phase of regrowth, but later on it was more affected by the number of branches. The introduction of Pareuchaetes pseudoinsulata to Indonesia, was successful only in North Sumatera. In Java it has not been reported to establish succesfully. The introduction of another biological control agent, Procecidochares conneca to Indonesia was shown to be sp ecific and upon release in West Java it established immediately. It spread exponentia lly in the first 6 months of its release. Field monitoring continues to eval uate the impact of the agents. Other biocontrol agents (Actmole anteas and Conotrachelus wilt be introduced to Indonesia in 1997 through ACIAR Project on the Biological Control of Chromolaena odorata in Indonesia and Papua New Guinea.

  8. Biological control of weeds in European crops: recent achievements and future work

    NARCIS (Netherlands)

    Müllerer-Schärer, H.; Greaves, M.P.

    2000-01-01

    Approaches to the biological control of weeds in arable crops and integration of biological weed control with other methods of weed management are broadly discussed. Various types of integrative approaches to biological control of weeds in crops have been studied within the framework of a concerted

  9. Models for integrated pest control and their biological implications.

    Science.gov (United States)

    Tang, Sanyi; Cheke, Robert A

    2008-09-01

    Successful integrated pest management (IPM) control programmes depend on many factors which include host-parasitoid ratios, starting densities, timings of parasitoid releases, dosages and timings of insecticide applications and levels of host-feeding and parasitism. Mathematical models can help us to clarify and predict the effects of such factors on the stability of host-parasitoid systems, which we illustrate here by extending the classical continuous and discrete host-parasitoid models to include an IPM control programme. The results indicate that one of three control methods can maintain the host level below the economic threshold (ET) in relation to different ET levels, initial densities of host and parasitoid populations and host-parasitoid ratios. The effects of host intrinsic growth rate and parasitoid searching efficiency on host mean outbreak period can be calculated numerically from the models presented. The instantaneous pest killing rate of an insecticide application is also estimated from the models. The results imply that the modelling methods described can help in the design of appropriate control strategies and assist management decision-making. The results also indicate that a high initial density of parasitoids (such as in inundative releases) and high parasitoid inter-generational survival rates will lead to more frequent host outbreaks and, therefore, greater economic damage. The biological implications of this counter intuitive result are discussed.

  10. Controlling seepage in discrete particle simulations of biological systems.

    Science.gov (United States)

    Gardiner, Bruce S; Joldes, Grand R; Wong, Kelvin K L; Tan, Chin Wee; Smith, David W

    2016-08-01

    It is now commonplace to represent materials in a simulation using assemblies of discrete particles. Sometimes, one wishes to maintain the integrity of boundaries between particle types, for example, when modelling multiple tissue layers. However, as the particle assembly evolves during a simulation, particles may pass across interfaces. This behaviour is referred to as 'seepage'. The aims of this study were (i) to examine the conditions for seepage through a confining particle membrane and (ii) to define some simple rules that can be employed to control seepage. Based on the force-deformation response of spheres with various sizes and stiffness, we develop analytic expressions for the force required to move a 'probe particle' between confining 'membrane particles'. We analyse the influence that particle's size and stiffness have on the maximum force that can act on the probe particle before the onset of seepage. The theoretical results are applied in the simulation of a biological cell under unconfined compression. PMID:26629728

  11. Parasites and biological invasions: parallels, interactions, and control.

    Science.gov (United States)

    Dunn, Alison M; Hatcher, Melanie J

    2015-05-01

    Species distributions are changing at an unprecedented rate owing to human activity. We examine how two key processes of redistribution - biological invasion and disease emergence - are interlinked. There are many parallels between invasion and emergence processes, and invasions can drive the spread of new diseases to wildlife. We examine the potential impacts of invasion and disease emergence, and discuss how these threats can be countered, focusing on biosecurity. In contrast with international policy on emerging diseases of humans and managed species, policy on invasive species and parasites of wildlife is fragmented, and the lack of international cooperation encourages individual parties to minimize their input into control. We call for international policy that acknowledges the strong links between emerging diseases and invasion risk.

  12. Dynamic phases in control and information processing biological circuits

    Science.gov (United States)

    Vaikuntanathan, Suriyanarayanan

    2015-03-01

    Recent work using the mathematical framework of large deviation theory has shown that fluctuations about the steady state can have a particularly rich structure even in extremely simple non-equilibrium systems [Phys. Rev. E. 89, 062108, 2014]. In certain instances the fluctuations can encode the presence of a dynamical phase with properties distinct from those of the steady state of the system. The transition between these two regimes is akin to a first order thermodynamic phase transition. Specifically, it implies an extreme sensitivity of the system to changes in certain sets of parameters. I will show that such dynamical phase transitions can serve as a general organizing principle to understand biological circuits that are involved in information processing and control. I will focus on two specific examples: adaptation control in E. coli chemotaxis and ultra sensitive response of the E. coli flagella motor, to illustrate these calculations. This work also elucidates the role played by energy dissipation in ensuring control and suggests general guidelines for the construction of robust non equilibrium circuits that perform various specified functions.

  13. A Biologically Inspired Cooperative Multi-Robot Control Architecture

    Science.gov (United States)

    Howsman, Tom; Craft, Mike; ONeil, Daniel; Howell, Joe T. (Technical Monitor)

    2002-01-01

    A prototype cooperative multi-robot control architecture suitable for the eventual construction of large space structures has been developed. In nature, there are numerous examples of complex architectures constructed by relatively simple insects, such as termites and wasps, which cooperatively assemble their nests. The prototype control architecture emulates this biological model. Actions of each of the autonomous robotic construction agents are only indirectly coordinated, thus mimicking the distributed construction processes of various social insects. The robotic construction agents perform their primary duties stigmergically i.e., without direct inter-agent communication and without a preprogrammed global blueprint of the final design. Communication and coordination between individual agents occurs indirectly through the sensed modifications that each agent makes to the structure. The global stigmergic building algorithm prototyped during the initial research assumes that the robotic builders only perceive the current state of the structure under construction. Simulation studies have established that an idealized form of the proposed architecture was indeed capable of producing representative large space structures with autonomous robots. This paper will explore the construction simulations in order to illustrate the multi-robot control architecture.

  14. Biological control of biofilms on membranes by metazoans.

    Science.gov (United States)

    Klein, Theresa; Zihlmann, David; Derlon, Nicolas; Isaacson, Carl; Szivak, Ilona; Weissbrodt, David G; Pronk, Wouter

    2016-01-01

    Traditionally, chemical and physical methods have been used to control biofouling on membranes by inactivating and removing the biofouling layer. Alternatively, the permeability can be increased using biological methods while accepting the presence of the biofouling layer. We have investigated two different types of metazoans for this purpose, the oligochaete Aelosoma hemprichi and the nematode Plectus aquatilis. The addition of these grazing metazoans in biofilm-controlled membrane systems resulted in a flux increase of 50% in presence of the oligochaetes (Aelosoma hemprichi), and a flux increase of 119-164% in presence of the nematodes (Plectus aquatilis) in comparison to the control system operated without metazoans. The change in flux resulted from (1) a change in the biofilm structure, from a homogeneous, cake-like biofilm to a more heterogeneous, porous structure and (2) a significant reduction in the thickness of the basal layer. Pyrosequencing data showed that due to the addition of the predators, also the community composition of the biofilm in terms of protists and bacteria was strongly affected. The results have implications for a range of membrane processes, including ultrafiltration for potable water production, membrane bioreactors and reverse osmosis.

  15. Economic value of biological control in integrated pest management of managed plant systems.

    Science.gov (United States)

    Naranjo, Steven E; Ellsworth, Peter C; Frisvold, George B

    2015-01-01

    Biological control is an underlying pillar of integrated pest management, yet little focus has been placed on assigning economic value to this key ecosystem service. Setting biological control on a firm economic foundation would help to broaden its utility and adoption for sustainable crop protection. Here we discuss approaches and methods available for valuation of biological control of arthropod pests by arthropod natural enemies and summarize economic evaluations in classical, augmentative, and conservation biological control. Emphasis is placed on valuation of conservation biological control, which has received little attention. We identify some of the challenges of and opportunities for applying economics to biological control to advance integrated pest management. Interaction among diverse scientists and stakeholders will be required to measure the direct and indirect costs and benefits of biological control that will allow farmers and others to internalize the benefits that incentivize and accelerate adoption for private and public good.

  16. Insect pathogens as biological control agents: Back to the future.

    Science.gov (United States)

    Lacey, L A; Grzywacz, D; Shapiro-Ilan, D I; Frutos, R; Brownbridge, M; Goettel, M S

    2015-11-01

    The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 1years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of microbial control agents (MCAs), particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for control of medically important pests including dipteran vectors. These pathogens

  17. Use of rhizobacteria and endophytes for biological control of weeds

    Directory of Open Access Journals (Sweden)

    Trognitz, Friederike

    2014-02-01

    Full Text Available Weeds cause severe yield losses in agriculture, with a maximum estimate of 34% of yield loss worldwide due to competition between the crops and the weeds for nutrition, light and humidity (OERKE, 2006. Invasive plants contribute partially to other problems. The pollen of common ragweed, Ambrosia artemisiifolia L., for example, is five times more allergenic than grass pollen; already ten pollen grains per m3 air can trigger allergy in sensitized patients, including rhinitis, conjunctivitis and asthma. This neophyte from America has extended the season of allergy in European patients to October. Common ragweed is currently most frequent in Hungary, France and Italy. In Austria, ragweed populations along roads have increased dramatically since 2000. The effective means to control this weed of the Asteraceae family are limited; a single plant can produce up to 6000 seeds which stay in the soil for 40 years. Control using selective herbicides is not possible within stands of the Asteraceae member sunflower. Efforts to use herbivore insects as biological control agents also failed due to the unavailability of insects specializing on this ragweed. The use of plant-associated rhizobacteria and endophytes as bio-herbicides offers a novel alternative to conventional methods. By analogy to experiences from other plant-microbe systems, the chances to find microbes of the desired characteristics are highest when isolating and testing specimens directly from ragweed plants. These organisms often have an extremely narrow host range that permits their use for the control of among several even closely related plant species growing together in a field.

  18. Evolutionary biology and genetic techniques for insect control.

    Science.gov (United States)

    Leftwich, Philip T; Bolton, Michael; Chapman, Tracey

    2016-01-01

    The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutilized methods such as reproductive interference, CRISPR technology, RNA interference (RNAi), and genetic underdominance. We focus on understanding principles and potential effectiveness from the perspective of evolutionary biology. This offers useful insights into mechanisms through which potential problems may be minimized, in much the same way that an understanding of how resistance evolves is key to slowing the spread of antibiotic and insecticide resistance. We conclude that there is much to gain from applying principles from the study of resistance in these other scenarios - specifically, the adoption of combinatorial approaches to minimize the spread of resistance evolution. We conclude by discussing the focused use of GM for insect pest control in the context of modern conservation planning under land-sparing scenarios. PMID:27087849

  19. Insect pathogens as biological control agents: Back to the future.

    Science.gov (United States)

    Lacey, L A; Grzywacz, D; Shapiro-Ilan, D I; Frutos, R; Brownbridge, M; Goettel, M S

    2015-11-01

    The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 1years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of microbial control agents (MCAs), particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for control of medically important pests including dipteran vectors. These pathogens

  20. Biological agents for whitefly control in Sardinian greenhouse tomatoes.

    Science.gov (United States)

    Nannini, M; Foddi, F; Manca, L; Pisci, R; Sanna, F

    2009-01-01

    To evaluate the effectiveness of alternative options for biocontrol of whiteflies in greenhouse tomatoes, an experiment was carried out during the cropping season 2005-2006 in one of Sardinia's major horticultural districts (S. Margherita di Pula, Cagliari, Italy). Twelve long-cycle and 17 short-cycle tomato crops (8 autumn and 9 spring crops) were surveyed. All of them were treated for insect pest control at the beginning of the growing season, but in 19 out of 29 cases whitefly natural enemies were also released (BCA greenhouses), at least four weeks after the last treatment. The following release programmes were tested: on autumn crops, 1 Macrolophus caliginosus and 12 Eretmocerus mundus/m2; on long-cycle crops, 1 M. caliginosus (released in autumn or spring) and 24 Encarsia formosa/m2 or 48 E. formosa/m2; on spring crops, 1 M. caliginosus and 24 E. formosa/m2 or 48 E. formosa/m2. The cost of each option was fixed at approximately 0.25 Euros/m2. The remaining greenhouses were maintained as controls (no BCA greenhouses). While whitefly and mirid populations were monitored monthly, whitefly species composition and mortality of immature stages were estimated at least twice during the growing season. On short-cycle autumn crops, the release of M. caliginosus and E. mundus produced negligible results in terms of Bemisia tabaci control. On long-cycle and spring crops, even though in June mortality rates in BCA greenhouses were found to be 2- to 3-fold higher than in no-BCA greenhouses, Trialeurodes vaporariorum population growth was not significantly affected by natural enemies. Among the beneficials tested, E. formosa proved to be the most effective; E. mundus and M. caliginosus did not establish well, probably owing to the persistence of insecticide residues, scarce prey availability and intense plant de-leafing. The presence of indigenous natural enemies of whiteflies was observed in most sites, but in general they contributed little to biological control. The

  1. Biological control of alien and invasive species in agriculture

    International Nuclear Information System (INIS)

    Agricultural production in Europe faces many challenges including limited availability of water, nitrogen input and fossil fuels. It is necessary, therefore, to identify methods of production and new technologies to increase the efficiency of the primary systems, guaranteeing amount of food, quality, safety and eco-sustainability . One of the most important aspects, though often undervalued in relation to the food chain, is the adversity of biological management of agricultural crops due to pests, pathogens or fitomizi with potential invasive already present in the territory or of recent origin alien. In this context, two main objectives should be implemented at the same time reduce production losses and protect the agro-ecosystem. To meet these expectations, as of January 1, 2015 all farms in the European Union countries are bound to the application of the Integrated Defense principles, as indicated by the Directive on the sustainable use of plant protection products (128/09 / EC) .In response to this and other new entomological emergencies plant health and medical-veterinary entomologist researchers of the Laboratory sustainable management of Agro-Ecosystems in ENEA, have directed their research towards the development of innovative systems for the sustainable control of invasive species of insects is in the agricultural sector that health.

  2. Biological Control of Meloidogyne hapla Using an Antagonistic Bacterium

    Directory of Open Access Journals (Sweden)

    Jiyeong Park

    2014-09-01

    Full Text Available We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN Meloidogyne hapla in carrot (Daucus carota subsp. sativus and tomato (Solanum lycopersicum. Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

  3. External noise control in inherently stochastic biological systems.

    Science.gov (United States)

    Zheng, Likun; Chen, Meng; Nie, Qing

    2012-11-01

    Biological systems are often subject to external noise from signal stimuli and environmental perturbations, as well as noises in the intracellular signal transduction pathway. Can different stochastic fluctuations interact to give rise to new emerging behaviors? How can a system reduce noise effects while still being capable of detecting changes in the input signal? Here, we study analytically and computationally the role of nonlinear feedback systems in controlling external noise with the presence of large internal noise. In addition to noise attenuation, we analyze derivatives of Fano factor to study systems' capability of differentiating signal inputs. We find effects of internal noise and external noise may be separated in one slow positive feedback loop system; in particular, the slow loop can decrease external noise and increase robustness of signaling with respect to fluctuations in rate constants, while maintaining the signal output specific to the input. For two feedback loops, we demonstrate that the influence of external noise mainly depends on how the fast loop responds to fluctuations in the input and the slow loop plays a limited role in determining the signal precision. Furthermore, in a dual loop system of one positive feedback and one negative feedback, a slower positive feedback always leads to better noise attenuation; in contrast, a slower negative feedback may not be more beneficial. Our results reveal interesting stochastic effects for systems containing both extrinsic and intrinsic noises, suggesting novel noise filtering strategies in inherently stochastic systems. PMID:23213267

  4. Prescribed fire effects on biological control of leafy spurge

    Science.gov (United States)

    Fellows, D.P.; Newton, W.E.

    1999-01-01

    The flea beetle, Aphthona nigriscutis Foudras, is a potentially useful agent for biological control of leafy spurge (Euphorbia esula L.) in grasslands devoted to wildlife conservation. However, effects of other grassland management practices on the persistence and dynamics of flea beetle populations are not well understood. We conducted small plot tests to evaluate 1) the effect of prerelease burning on establishment of A. nigriscutis colonies, and 2) the ability of established A. nigriscutis colonies to survive prescribed fire. More colonies established on plots that were burned prior to beetle release (83% establishment) than on unburned plots (37% establishment), possibly due to litter reduction and baring of the soil surface. However, most colonies established with the aid of fire did not survive past the first generation unless the habitat was otherwise suitable for the species, and we conclude that the primary benefit of prerelease burning is increased recruitment of A. nigriscutis during the first few generations. Established colonies were not harmed by burns in October and May. Both spring and fall burns resulted in an increase in leafy spurge stem density during the first growing season, but stem density declined to the preburn level by the second growing season.

  5. 75 FR 64984 - Availability of an Environmental Assessment for a Biological Control Agent for Hawkweeds

    Science.gov (United States)

    2010-10-21

    ... Assessment for a Biological Control Agent for Hawkweeds AGENCY: Animal and Plant Health Inspection Service... the control of hawkweeds (Hieracium spp.). The environmental assessment considers the effects of, and... States as a biological control agent to reduce the severity of infestations of hawkweeds. We are...

  6. Predatory hoverflies increase oviposition in response to colour stimuli offering no reward: implications for biological control

    OpenAIRE

    Day, R.L.; Hickman, J.M.; Sprague, R.I.; Wratten, S. D.

    2015-01-01

    There are increasing efforts worldwide to engineer agroecosystems to enhance ecosystem services such as carbon storage, minimisation of erosion, and biological control of pests. A key group of insect biological control agents is the hoverflies (Diptera: Syrphidae). While adult Syrphidae are pollen and nectar feeders, the larvae of many species are aphidophagous, thus demonstrating life-history omnivory and their potentially important role in the biological control of aphids and other pests. S...

  7. Eicosanoids: Exploiting Insect Immunity to Improve Biological Control Programs

    Directory of Open Access Journals (Sweden)

    David Stanley

    2012-05-01

    Full Text Available Insects, like all invertebrates, express robust innate, but not adaptive, immune reactions to infection and invasion. Insect immunity is usually resolved into three major components. The integument serves as a physical barrier to infections. Within the hemocoel, the circulating hemocytes are the temporal first line of defense, responsible for clearing the majority of infecting bacterial cells from circulation. Specific cellular defenses include phagocytosis, microaggregation of hemocytes with adhering bacteria, nodulation and encapsulation. Infections also stimulate the humoral component of immunity, which involves the induced expression of genes encoding antimicrobial peptides and activation of prophenoloxidase. These peptides appear in the hemolymph of challenged insects 6–12 hours after the challenge. Prostaglandins and other eicosanoids are crucial mediators of innate immune responses. Eicosanoid biosynthesis is stimulated by infection in insects. Inhibition of eicosanoid biosynthesis lethally renders experimental insects unable to clear bacterial infection from hemolymph. Eicosanoids mediate specific cell actions, including phagocytosis, microaggregation, nodulation, hemocyte migration, hemocyte spreading and the release of prophenoloxidase from oenocytoids. Some invaders have evolved mechanisms to suppress insect immunity; a few of them suppress immunity by targeting the first step in the eicosanoid biosynthesis pathways, the enzyme phospholipase A2. We proposed research designed to cripple insect immunity as a technology to improve biological control of insects. We used dsRNA to silence insect genes encoding phospholipase A2, and thereby inhibited the nodulation reaction to infection. The purpose of this article is to place our view of applying dsRNA technologies into the context of eicosanoid actions in insect immunity. The long-term significance of research in this area lies in developing new pest management

  8. WILD PIGS: BIOLOGY, DAMAGE, CONTROL TECHINQUES AND MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, John; Brisbin, I. Lehr

    2009-12-31

    about anything; and, they can live just about anywhere. On top of that, wild pigs are both very difficult to control and, with the possible exception of island ecosystems, almost impossible to eradicate (Dickson et al. 2001, Sweeney et al. 2003). The solution to the wild pig problem has not been readily apparent. The ultimate answer as to how to control these animals has not been found to date. In many ways, wild pigs are America's most successful large invasive species. All of which means that wild pigs are a veritable nightmare for land and resource managers trying to keep the numbers of these animals and the damage that they do under control. Since the more that one knows about an invasive species, the easier it is to deal with and hopefully control. For wild pigs then, it is better to 'know thy enemy' than to not, especially if one expects to be able to successfully control them. In an effort to better 'know thy enemy,' a two-day symposium was held in Augusta, Georgia, on April 21-22, 2004. This symposium was organized and sponsored by U.S.D.A. Forest Service-Savannah River (USFS-SR), U. S. Department of Energy-Savannah River Operations Office (DOE-SR), the Westinghouse Savannah River Company (WSRC), the South Carolina Chapter of the Soil & Water Conservation Society, and the Savannah River Ecology Laboratory (SREL). The goal of this symposium was to assemble researchers and land managers to first address various aspects of the biology and damage of wild pigs, and then review the control techniques and management of this invasive species. The result would then be a collected synopsis of what is known about wild pigs in the United States. Although the focus of the symposium was primarily directed toward federal agencies, presenters also included professionals from academic institutions, and private-sector control contractors and land managers. Most of the organizations associated with implementing this symposium were affiliated with the

  9. WILD PIGS: BIOLOGY, DAMAGE, CONTROL TECHINQUES AND MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, John; Brisbin, I. Lehr

    2009-12-31

    about anything; and, they can live just about anywhere. On top of that, wild pigs are both very difficult to control and, with the possible exception of island ecosystems, almost impossible to eradicate (Dickson et al. 2001, Sweeney et al. 2003). The solution to the wild pig problem has not been readily apparent. The ultimate answer as to how to control these animals has not been found to date. In many ways, wild pigs are America's most successful large invasive species. All of which means that wild pigs are a veritable nightmare for land and resource managers trying to keep the numbers of these animals and the damage that they do under control. Since the more that one knows about an invasive species, the easier it is to deal with and hopefully control. For wild pigs then, it is better to 'know thy enemy' than to not, especially if one expects to be able to successfully control them. In an effort to better 'know thy enemy,' a two-day symposium was held in Augusta, Georgia, on April 21-22, 2004. This symposium was organized and sponsored by U.S.D.A. Forest Service-Savannah River (USFS-SR), U. S. Department of Energy-Savannah River Operations Office (DOE-SR), the Westinghouse Savannah River Company (WSRC), the South Carolina Chapter of the Soil & Water Conservation Society, and the Savannah River Ecology Laboratory (SREL). The goal of this symposium was to assemble researchers and land managers to first address various aspects of the biology and damage of wild pigs, and then review the control techniques and management of this invasive species. The result would then be a collected synopsis of what is known about wild pigs in the United States. Although the focus of the symposium was primarily directed toward federal agencies, presenters also included professionals from academic institutions, and private-sector control contractors and land managers. Most of the organizations associated with implementing this symposium were affiliated with the

  10. Bit by bit control of nonlinear ecological and biological networks using Evolutionary Network Control

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2016-06-01

    Full Text Available Evolutionary Network Control (ENC has been first introduced in 2013 to effectively subdue network-like systems. ENC opposes the idea, very common in the scientific literature, that controllability of networks should be based on the identification of the set of driver nodes that can guide the system's dynamics, in other words on the choice of a subset of nodes that should be selected to be permanently controlled. ENC has proven to be effective in the global control (i.e. the focus is on mastery of the final state of network dynamics of linear and nonlinear networks, and in the local (i.e. the focus is on the step-by-step ascendancy of network dynamics control of linear networks. In this work, ENC is applied to the local control of nonlinear networks. Using the Lotka-Volterra model as a case study, I show here that ENC is capable of locally driving nonlinear networks as well, so that also intermediate steps (not only the final state are under our strict control. ENC can be readily applied to any kind of ecological, biological, economic and network-like system.

  11. Evaluation of Orius species for biological control of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

    OpenAIRE

    Tommasini, M.G.

    2003-01-01

    Key words: Thysanoptera, Frankliniella occidentalis, Heteroptera, Orius leavigatu, Orius majusculu, Orius niger, Orius insidiosus, Biology, Diapause, Biological control.The overall aim of this research was to develop a biological control programme for F. occidentalis through the selection of an efficient beneficial arthropod. First, a general review of the literature about thrips pest species in Europe and in particular of Frankliniella occidentalis (Pergande) (Western Flower Thrips) was made...

  12. Potential for widespread application of biological control of stored-product pests

    DEFF Research Database (Denmark)

    Hansen, Lise Stengaard

    2007-01-01

    Biological control of stored product pests has substantial potential in Europe". This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biological...... control of stored-product pests and has considered a number of existing and potential fields for application of biological control. Three situations were identified where biological control would be a valuable component of integrated pest management: (1) Empty room treatment against stored-product mites......, beetles and moths; (2) Preventative treatment of bulk commodities against weevils (Sitophilus spp.) and storage mites; (3) Preventative application of egg-parasitoids against moths in packaged products. Development of methods for biological control and of mass production of natural enemies...

  13. Evolutionary game based control for biological systems with applications in drug delivery.

    Science.gov (United States)

    Li, Xiaobo; Lenaghan, Scott C; Zhang, Mingjun

    2013-06-01

    Control engineering and analysis of biological systems have become increasingly important for systems and synthetic biology. Unfortunately, no widely accepted control framework is currently available for these systems, especially at the cell and molecular levels. This is partially due to the lack of appropriate mathematical models to describe the unique dynamics of biological systems, and the lack of implementation techniques, such as ultra-fast and ultra-small devices and corresponding control algorithms. This paper proposes a control framework for biological systems subject to dynamics that exhibit adaptive behavior under evolutionary pressures. The control framework was formulated based on evolutionary game based modeling, which integrates both the internal dynamics and the population dynamics. In the proposed control framework, the adaptive behavior was characterized as an internal dynamic, and the external environment was regarded as an external control input. The proposed open-interface control framework can be integrated with additional control algorithms for control of biological systems. To demonstrate the effectiveness of the proposed framework, an optimal control strategy was developed and validated for drug delivery using the pathogen Giardia lamblia as a test case. In principle, the proposed control framework can be applied to any biological system exhibiting adaptive behavior under evolutionary pressures.

  14. Biology of Leipothrix dipsacivagus (Acari: Eriophyidae), a candidate for biological control of invasive teasels (Dipsacus spp.)

    Science.gov (United States)

    The present study describes key aspects of the biology of Leipothrix dipsacivagus, an eriophyid mite that was recently described as a new species from Dipsacus fullonum and D. laciniatus (Dipsacaceae). Preliminary host-specificity tests have shown that it can develop and reproduce only on Dipsacus s...

  15. BIOLOGICAL CONTROL OF THE CROWN GALL AGROBACTERIUM TUMEFACIENS

    OpenAIRE

    Lemanova, N.; M. Mager

    2011-01-01

    Genetic date transfer T-DNA from a pathogen to a plant cell occur the process of tumefaction on vineyard and fruit varieties. Treatment of woundings by biologic preparation Paurin (suspension of bacterial cells of Pseudomonas fluorescens cr-330d) deteriorates the interaction of bacteria-pathogen with the cell of host plant. Application of this preparation decrease the quantity of plants with tumors

  16. Biological stability of drinking water: Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and ca

  17. Synthetic biology and regulatory networks: where metabolic systems biology meets control engineering

    OpenAIRE

    He, Fei; Murabito, Ettore; Westerhoff, Hans V

    2016-01-01

    Metabolic pathways can be engineered to maximize the synthesis of various products of interest. With the advent of computational systems biology, this endeavour is usually carried out through in silico theoretical studies with the aim to guide and complement further in vitro and in vivo experimental efforts. Clearly, what counts is the result in vivo, not only in terms of maximal productivity but also robustness against environmental perturbations. Engineering an organism towards an increased...

  18. The biological control as a strategy to support nontraditional agricultural exports in Peru: An empirical analysis

    Directory of Open Access Journals (Sweden)

    Franklin Duarte Cueva

    2012-12-01

    Full Text Available The study is oriented to explore the general characteristics of agriculture, the biological control as a pest control mechanism and agro export industry. In this context, we try to promote the use of biological control as a strategy to support nontraditional exports related to products such as asparagus and fresh avocados grown in the La Libertad Department (Peru, through an agronomic and management approach. Biological control is the basis of integrated pest management (IPM and contributes to the conservation of agricultural ecosystems allowing to export companies reduce costs, fulfill international phytosanitary measures and supports the preservation of the environment and health. Thus, the Peruvian agro export companies could build a sustainable competitive advantage and seek a positioning as socially responsible firms. We analyze variables such as crop statistics, comparative costs between biological control and chemical control, main destination markets for asparagus and fresh avocados, international standards, among others.

  19. Quality of environmental impact assessment (EIA) reports on biological pest control / Thea Henriette Carroll

    OpenAIRE

    Carroll, Thea Henriette

    2006-01-01

    Decision making regarding the release of biological control agents for invasive species such as lantana, Lantana camara, requires the consideration and evaluation of environmental impact assessment (EIA) reports by a competent authority. Although various biological control agents have been authorised for release into the environment for the control of lantana, the quality of the EIA reports that form the basis for decision making has never been evaluated. The evaluation of the ...

  20. Probiotic Bacteria as Biological Control Agents in Aquaculture

    OpenAIRE

    Verschuere, L.; Rombaut, G.; Sorgeloos, P.; Verstraete, W.

    2000-01-01

    There is an urgent need in aquaculture to develop microbial control strategies, since disease outbreaks are recognized as important constraints to aquaculture production and trade and since the development of antibiotic resistance has become a matter of growing concern. One of the alternatives to antimicrobials in disease control could be the use of probiotic bacteria as microbial control agents. This review describes the state of the art of probiotic research in the culture of fish, crustace...

  1. Safety of biologics in rheumatoid arthritis: data from randomized controlled trials and registries

    OpenAIRE

    Codreanu C; Damjanov N

    2015-01-01

    Catalin O Codreanu,1 Nemanja Damjanov2 1Rheumatology Department, Center of Rheumatic Diseases, Bucharest, Romania; 2Institute of Rheumatology, School of Medicine, University of Belgrade, Belgrade, SerbiaAbstract: Over the past decade, the use of biologics has significantly changed the management of rheumatoid arthritis (RA). Biologics selectively target components of the immune system, resulting in better disease control. However, the growing use of biologics in RA has increased safety concer...

  2. Biological control through intraguild predation: case studies in pest control, invasive species and range expansion.

    Science.gov (United States)

    Bampfylde, C J; Lewis, M A

    2007-04-01

    Intraguild predation (IGP), the interaction between species that eat each other and compete for shared resources, is ubiquitous in nature. We document its occurrence across a wide range of taxonomic groups and ecosystems with particular reference to non-indigenous species and agricultural pests. The consequences of IGP are complex and difficult to interpret. The purpose of this paper is to provide a modelling framework for the analysis of IGP in a spatial context. We start by considering a spatially homogeneous system and find the conditions for predator and prey to exclude each other, to coexist and for alternative stable states. Management alternatives for the control of invasive or pest species through IGP are presented for the spatially homogeneous system. We extend the model to include movement of predator and prey. In this spatial context, it is possible to switch between alternative stable steady states through local perturbations that give rise to travelling waves of extinction or control. The direction of the travelling wave depends on the details of the nonlinear intraguild interactions, but can be calculated explicitly. This spatial phenomenon suggests means by which invasions succeed or fail, and yields new methods for spatial biological control. Freshwater case studies are used to illustrate the outcomes.

  3. Evaluation of biological control agents for mosquitoes control in artificial breeding places

    Institute of Scientific and Technical Information of China (English)

    Salim Abadi Yaser; Vatandoost Hassan; Rassi Yavar; Abai Mohammad Reza; Sanei Dehkordi Ali Reza; Paksa Azim

    2010-01-01

    Objective:To evaluate the entomological impact of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on mosquitoes control in artificial breeding places.Methods:A Latin square design with 4 replicates was performed in order to evaluate the efficacy of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on larva. The larvicide was applied at the dosage of 100 mg a.h/ha,Bacillus thuringiensis at the recommended dosage and 10 fishes per m2 were applied at 1í1 m2 artificial breeding sites. The larval densities for both anopheline and culicine were counted according to larvae /10 dippers prior and 24 h after application.Results:All three control agents are effective for mosquito density reduction, and the difference between the three agents and the control is significant (P<0.05). There is also significant difference among chlorpyrifos-methyl,Bacillus thuringiensis andGambusia affinis.Bacillus thuringiensisexhibited more reduction on mosquito larval density than fish and larvicide (P<0.05).Conclusions:Bacillus thuringiensis in comparison with two other agents is the appropriate method for larviciding in the breeding places. Although long term assessing for biological activities as well as monitoring and mapping of resistance is required.

  4. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  5. Anaerobic Digestion. Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Carnegie, John W., Ed.

    This student manual contains the textual material for a four-lesson unit on anaerobic digestion control. Areas addressed include: (1) anaerobic sludge digestion (considering the nature of raw sludge, purposes of anaerobic digestion, the results of digestion, types of equipment, and other topics); (2) digester process control (considering feeding…

  6. Biological control of greenhouse whitefly (Trialeurodes vaporariorum) with fungal insecticides.

    Science.gov (United States)

    Siongers, C; Coosemans, J

    2003-01-01

    The influence of the biological insecticide Botanigard (Beauveria bassiana) on different developmental stages of the greenhouse whitefly (Trialeurodes vaporariorum) has been tested and compared with the influence of Preferal (Paecilomyces fumosoroseus), also a biological product. Six experiments were set up to test the two products on eggs, which were four and seven days old, on larvae of the first, second/third and fourth stage and to test the effect on egg-deposition. These experiments were all conducted on cucumber. Egg-deposition was limited to a small area on the leaf by using leaf cages. To evaluate these tests the number of eggs or larvae developed to the next stage has been counted and compared to the total amount of eggs or larvae on the leaves. The results revealed that Botanigard has an effect on the larval stages. The first larval stage is most sensitive; the next stages have a decreasing sensitivity. There was no influence on the hatching of the eggs, but a treatment short before the hatching could have a residual effect on the new nymphs. When the treatment with Botanigard is performed shortly before a moult or a fungicide treatment, the efficacy of the product decreases significantly. The influence of Preferal on the greenhouse whitefly is, under the same circumstances, less obvious.

  7. Biological control of wood decay against fungal infection.

    Science.gov (United States)

    Susi, Petri; Aktuganov, Gleb; Himanen, Juha; Korpela, Timo

    2011-07-01

    Wood (timber) is an important raw material for various purposes, and having biological composition it is susceptible to deterioration by various agents. The history of wood protection by impregnation with synthetic chemicals is almost two hundred years old. However, the ever-increasing public concern and the new environmental regulations on the use of chemicals have created the need for the development and the use of alternative methods for wood protection. Biological wood protection by antagonistic microbes alone or in combination with (bio)chemicals, is one of the most promising ways for the environmentally sound wood protection. The most effective biocontrol antagonists belong to genera Trichoderma, Gliocladium, Bacillus, Pseudomonas and Streptomyces. They compete for an ecological niche by consuming available nutrients as well as by secreting a spectrum of biochemicals effective against various fungal pathogens. The biochemicals include cell wall-degrading enzymes, siderophores, chelating iron and a wide variety of volatile and non-volatile antibiotics. In this review, the nature and the function of the antagonistic microbes in wood protection are discussed.

  8. Biological control of the strawberry mite by using predatory mites

    OpenAIRE

    Tuovinen, Tuomo

    2003-01-01

    Strawberry mite control by Neoseiulus cucumeris has proven economically feasible. To achieve a better integration of biocontrol with growing techniques and outdoor conditions development of alternative approaches by native phytoseiid species are required.

  9. Biological approaches for control of root pathogens of strawberry.

    Science.gov (United States)

    Martin, F N; Bull, C T

    2002-12-01

    ABSTRACT Soil fumigation with methyl bromide plus chloropicrin is used as a preplant treatment to control a broad range of pathogens in high-value annual crop production systems. In California, fumigation is used on approximately 10,125 ha of strawberry production to control pathogens ranging from Verticillium dahliae to root pruning pathogens such as Pythium, Rhizoctonia, or Cylindrocarpon spp. In addition to pathogen control, fumigation also causes an enhanced growth response of the plant and reduces weed pressure. The development of successful, long-term cost effective biocontrol strategies most likely will require the development of an integrated systems approach that incorporates diverse aspects of the crop production system. Although application of single microbial inoculants may provide some level of control for specific production problems, it will be a challenge to provide the broad spectrum of activity needed in production fields. PMID:18943893

  10. Bioprospecting endophytic bacteria for biological control of coffee leaf rust

    OpenAIRE

    Shiomi Humberto Franco; Silva Harllen Sandro Alves; Melo Itamar Soares de; Nunes Flávia Vieira; Bettiol Wagner

    2006-01-01

    Suppression of plant diseases due to the action of endophytic microorganisms has been demonstrated in several pathosystems. Experiments under controlled conditions involving endophytic bacteria isolated from leaves and branches of Coffea arabica L and Coffea robusta L were conducted with the objective of evaluating the inhibition of germination of Hemileia vastatrix Berk. & Br., race II, urediniospores and the control of coffee leaf rust development in tests with leaf discs, detached leaves, ...

  11. Biological control and management of the detoxication wastewater treatment technologies

    Directory of Open Access Journals (Sweden)

    Topalova Yana

    2007-01-01

    Full Text Available Detoxication technologies require the combination of theoretical and practical knowledge of xenobiotic biodegradation, wastewater treatment technologies, and management rules. The purpose of this complicated combination is to propose specialized strategies for detoxication, based on lab- and pilot-scale modeling. These strategies include preliminary created algorithms for preventing the risk of water pollution and sediments. The technologies and algorithms are essentially important outcome, applied in the textile, pharmaceutical, cosmetic, woodtreating, and oiltreating industries. In this paper four rehabilitation technologies for pretreatment of water contaminated by pentachlorophenol (PCP have been developed in the frame of the European and Bulgarian National projects. Emphasize is put on the biological systems and their potential of detoxication management. The light and transmission electron microscopy of the reconstructed activated sludges the microbial, kinetic and enzymological indicators are presented and approved as critical points in the biocontrol.

  12. Comparative evaluation of two populations of Pseudophilothrips ichini as candidates for biological control of Brazilian peppertree

    Science.gov (United States)

    Brazilian peppertree, Schinus terebinthifolius Raddi (Sapindales: Anacardiaceae) is one of the worst invasive species in Florida. The thrips Pseudophilothrips ichini Hood (Thysanoptera: Phlaeothripidae) is being considered as a potential biological control agent of Brazilian peppertree. Two populati...

  13. High-throughput assay for optimising microbial biological control agent production and delivery

    Science.gov (United States)

    Lack of technologies to produce and deliver effective biological control agents (BCAs) is a major barrier to their commercialization. A myriad of variables associated with BCA cultivation, formulation, drying, storage, and reconstitution processes complicates agent quality maximization. An efficie...

  14. Holarchical Systems and Emotional Holons : Biologically-Inspired System Designs for Control of Autonomous Aerial Vehicles

    Science.gov (United States)

    Ippolito, Corey; Plice, Laura; Pisanich, Greg

    2003-01-01

    The BEES (Bio-inspired Engineering for Exploration Systems) for Mars project at NASA Ames Research Center has the goal of developing bio-inspired flight control strategies to enable aerial explorers for Mars scientific investigations. This paper presents a summary of our ongoing research into biologically inspired system designs for control of unmanned autonomous aerial vehicle communities for Mars exploration. First, we present cooperative design considerations for robotic explorers based on the holarchical nature of biological systems and communities. Second, an outline of an architecture for cognitive decision making and control of individual robotic explorers is presented, modeled after the emotional nervous system of cognitive biological systems. Keywords: Holarchy, Biologically Inspired, Emotional UAV Flight Control

  15. Historical perspective on biological control of postharvest diseases – past, present, and future

    Science.gov (United States)

    The birth of the field of biological control of postharvest diseases can be traced back to 1984 when a researcher testing an antagonist (Bacillus subtilis) in the field to control brown rot of peaches (caused by Monilinia fructicola ) decided to apply the antagonist directly to the peach to control ...

  16. Biological control of aphids in the presence of thrips and their enemies

    NARCIS (Netherlands)

    Messelink, G.J.; Bloemhard, C.M.J.; Sabelis, M.W.; Janssen, A.

    2013-01-01

    Generalist predators are often used in biological control programs, although they can be detrimental for pest control through interference with other natural enemies. Here, we assess the effects of generalist natural enemies on the control of two major pest species in sweet pepper: the green peach a

  17. 75 FR 28232 - Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly...

    Science.gov (United States)

    2010-05-20

    ... Control Agent for Hemlock Woolly Adelgid AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... Plant Health Inspection Service has prepared an environmental assessment relative to the control of... a biological control agent to reduce the severity of hemlock woolly adelgid infestations. We...

  18. 77 FR 46373 - Availability of an Environmental Assessment for a Biological Control Agent for Hemlock Woolly...

    Science.gov (United States)

    2012-08-03

    ... Control Agent for Hemlock Woolly Adelgid AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION... prepared an environmental assessment relative to the release of Symnus coniferarum to control hemlock... of Symnus coniferarum into the eastern United States for use as a biological control agent to...

  19. Metabolic behavior of bacterial biological control agents in soil and plant rhizospheres

    Science.gov (United States)

    Biological control provides an attractive alternative to chemical pesticides for the control of plant diseases. To date, however, few biocontrol products have been developed successfully at the commercial level. This stems largely from variability in disease control performance that is often obser...

  20. Biological control of banana black Sigatoka disease with Trichoderma

    Directory of Open Access Journals (Sweden)

    Poholl Adan Sagratzki Cavero

    2015-06-01

    Full Text Available Black Sigatoka disease caused by Mycosphaerella fijiensis is the most severe banana disease worldwide. The pathogen is in an invasive phase in Brazil and is already present in most States of the country. The potential of 29 isolates of Trichoderma spp. was studied for the control of black Sigatoka disease under field conditions. Four isolates were able to significantly reduce disease severity and were further tested in a second field experiment. Isolate 2.047 showed the best results in both field experiments and was selected for fungicide sensitivity tests and mass production. This isolate was identified as Trichoderma atroviride by sequencing fragments of the ITS region of the rDNA and tef-1α of the RNA polymerase. Trichoderma atroviride was as effective as the fungicide Azoxystrobin, which is recommended for controlling black Sigatoka. This biocontrol agent has potential to control the disease and may be scaled-up for field applications on rice-based solid fermentation

  1. Novel ESCRT functions in cell biology: spiraling out of control?

    Science.gov (United States)

    Campsteijn, Coen; Vietri, Marina; Stenmark, Harald

    2016-08-01

    The endosomal sorting complex required for transport (ESCRT), originally identified for its role in endosomal protein sorting and biogenesis of multivesicular endosomes (MVEs), has proven to be a versatile machinery for involution and scission of narrow membrane invaginations filled with cytosol. Budding of enveloped viruses and cytokinetic abscission were early described functions for the ESCRT machinery, and recently a number of new ESCRT functions have emerged. These include cytokinetic abscission checkpoint control, plasma membrane repair, exovesicle release, quality control of nuclear pore complexes, neuron pruning, and sealing of the newly formed nuclear envelope. Here we review these novel ESCRT mechanisms and discuss similarities and differences between the various ESCRT-dependent activities.

  2. Anaerobic Digestion. Instructor's Guide. Biological Treatment Process Control.

    Science.gov (United States)

    Carnegie, John W., Ed.

    This instructor's guide contains materials needed to teach a four-lesson unit on anaerobic digestion control. These materials include: (1) unit overview; (2) lesson plans; (3) lecture outlines; (4) student worksheets for each lesson (with answers); and (5) two copies of a final quiz (with and without answers). Lesson 1 is a review of the theory of…

  3. Ecological risks of biological control agents: impacts on IPM

    NARCIS (Netherlands)

    Hokkanen, H.M.T.; Lenteren, van J.C.; Menzler-Hokkanen, I.

    2007-01-01

    Since the early days of integrated pest management a sound ecological foundation has been considered essential for the development of effective systems. From time to time, there have been attempts to evaluate the ways in which ecological theory is exploited in pest control, and to review the lessons

  4. Microbial control of the dark end of the biological pump.

    Science.gov (United States)

    Herndl, Gerhard J; Reinthaler, Thomas

    2013-09-01

    A fraction of the carbon captured by phytoplankton in the sunlit surface ocean sinks to depth as dead organic matter and faecal material. The microbial breakdown of this material in the subsurface ocean generates carbon dioxide. Collectively, this microbially mediated flux of carbon from the atmosphere to the ocean interior is termed the biological pump. In recent decades it has become clear that the composition of the phytoplankton community in the surface ocean largely determines the quantity and quality of organic matter that sinks to depth. This settling organic matter, however, is not sufficient to meet the energy demands of microbes in the dark ocean. Two additional sources of organic matter have been identified: non-sinking organic particles of debated origin that escape capture by sediment traps and exhibit stable concentrations throughout the dark ocean, and microbes that convert inorganic carbon into organic matter. Whether these two sources can together account for the significant mismatch between organic matter consumption and supply in the dark ocean remains to be seen. It is clear, however, that the microbial community of the deep ocean works in a fundamentally different way from surface water communities.

  5. The biological basis for the control of prenatal irradiation

    International Nuclear Information System (INIS)

    The embryo and fetus have been generally considered to be more sensitive than the adult to the detrimental effects of radiation exposure. In particular, recent re-evaluations of epidemiological data on human population exposed to radiation have suggested that there may be greater sensitivity than heretofore recognized to the induction of mental retardation and reduced intelligence by exposure during gestation. To assist national authorities in evaluating this problem and establishing appropriate protection measures for limiting the dose to the embryo and fetus and, thus, to pregnant or potentially pregnant women, the Nuclear Energy Agency has appointed a Group of Consultants to assemble and evaluate the biological data relevant to the protection of the human conceptus, and to make recommendations for achieving this in the operational practice. The Group has surveyed the human data dealing with the biologcal effects of radiation exposure at low doses, and has supplemented this with information derived from animal studies. The Group has also taken full account of the studies and recommendations issued in this area by other international organizations, primarily the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Commission on Radiological Protection (ICRP). This report is published under the responsibility of the Secretary General of the OECD, and does not commit Member governments of the Organization

  6. The Potential for the Integration of Nuclear Techniques in Arthropod Biological Control

    International Nuclear Information System (INIS)

    Biological control is today being practised more widely than ever before and its popularity looks set to increase further in the future. While the discipline has historically been dominated by 'classical' biological control (the one-off introduction of natural enemies to control pests in their adventive range) augmentative biological control (the repeated introduction of biocontrol agents to a particular crop or forest) has increased substantially over the past 20 years and is likely to increase in importance further in the future. This view is supported by an assessment of some of the key issues facing the discipline of biological control today. There is no clear role for nuclear techniques in the future of classical biological control. However the use of irradiation as a means of creating increased rates of mutation in natural enemy populations being selected for enhanced beneficial traits (such as insecticide resistance), might be useful and could be investigated further. There is scope for the use of irradiation in killing or sterilising insect diets and hosts, a technique which has been used for over 25 years without gaining wide acceptance. Augmentative biological control as an adjunct to SIT may have a role in future pest control campaigns, although it is likely to prove difficult to provide a clear economic justification given the technical difficulties of measuring separately the effects of the two techniques. It is suggested that the technical advances in project development and implementation (e.g. insect rearing techniques and field application) which have been made by SIT practitioners have a potentially useful role in assisting the development of improved production and delivery of biological control agents for augmentative release (author)

  7. Mechanization and Control Concepts for Biologically Inspired Micro Aerial Vehicles

    Science.gov (United States)

    Raney, David L.; Slominski, Eric C.

    2003-01-01

    It is possible that MAV designs of the future will exploit flapping flight in order to perform missions that require extreme agility, such as rapid flight beneath a forest canopy or within the confines of a building. Many of nature's most agile flyers generate flapping motions through resonant excitation of an aeroelastically tailored structure: muscle tissue is used to excite a vibratory mode of their flexible wing structure that creates propulsion and lift. A number of MAV concepts have been proposed that would operate in a similar fashion. This paper describes an ongoing research activity in which mechanization and control concepts with application to resonant flapping MAVs are being explored. Structural approaches, mechanical design, sensing and wingbeat control concepts inspired by hummingbirds, bats and insects are examined. Experimental results from a testbed capable of generating vibratory wingbeat patterns that approximately match those exhibited by hummingbirds in hover, cruise, and reverse flight are presented.

  8. Biological Control of Mosquito Vectors: Past, Present, and Future

    Directory of Open Access Journals (Sweden)

    Giovanni Benelli

    2016-10-01

    Full Text Available Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs is available for most of these diseases andvectorcontrolisstillthemainformofprevention. Thelimitationsoftraditionalinsecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In thisreview, weoutline non-insecticide basedstrategiesthat havebeenimplemented orare currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies.

  9. Controlled flight of a biologically inspired, insect-scale robot.

    Science.gov (United States)

    Ma, Kevin Y; Chirarattananon, Pakpong; Fuller, Sawyer B; Wood, Robert J

    2013-05-01

    Flies are among the most agile flying creatures on Earth. To mimic this aerial prowess in a similarly sized robot requires tiny, high-efficiency mechanical components that pose miniaturization challenges governed by force-scaling laws, suggesting unconventional solutions for propulsion, actuation, and manufacturing. To this end, we developed high-power-density piezoelectric flight muscles and a manufacturing methodology capable of rapidly prototyping articulated, flexure-based sub-millimeter mechanisms. We built an 80-milligram, insect-scale, flapping-wing robot modeled loosely on the morphology of flies. Using a modular approach to flight control that relies on limited information about the robot's dynamics, we demonstrated tethered but unconstrained stable hovering and basic controlled flight maneuvers. The result validates a sufficient suite of innovations for achieving artificial, insect-like flight. PMID:23641114

  10. Evolutionary biology and genetic techniques for insect control

    OpenAIRE

    Leftwich, Philip; Bolton, Michael; Chapman, Tracey

    2016-01-01

    Abstract The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutil...

  11. Controlled light field concentration through turbid biological membrane for phototherapy

    OpenAIRE

    Wang, Fujuan; He, Hexiang; Zhuang, Huichang; Xie, Xiangsheng; Yang, Zhenchong; Cai, Zhigang; Gu, Huaiyu; Zhou, Jianying

    2015-01-01

    Laser propagation through a turbid rat dura mater membrane is shown to be controllable with a wavefront modulation technique. The scattered light field can be refocused into a target area behind the rat dura mater membrane with a 110 times intensity enhancement using a spatial light modulator. The efficient laser intensity concentration system is demonstrated to imitate the phototherapy for human brain tumors. The power density in the target area is enhanced more than 200 times compared with ...

  12. International Issues in Relation to Biological Control Regulation, Coordination and Accountability

    International Nuclear Information System (INIS)

    Biological control has been an accepted and effective method of pest management for over 100 years. Several recent reports from the Office of Technology Assessment, the National Research Council of the National Academy of Sciences, the U.S. Department of Agriculture and others have advised increasing research and development of biologically-based technologies (BBTs) for pest management. In addition, several reports have identified elements of regulation, coordination, and accountability that should be in place for a biological control program to be highly successful. This report summarizes perspectives on regulation, coordination and accountability that were presented in key documents important to the future of biological control, particularly Carruthers and Petroff (1997), Delfosse et al. (1996a,b), NRC (1996) and OTA (1995). (author)

  13. Parasitoids of Queensland Fruit Fly Bactrocera tryoni in Australia and Prospects for Improved Biological Control

    Directory of Open Access Journals (Sweden)

    Olivia L. Reynolds

    2012-10-01

    Full Text Available This review draws together available information on the biology, methods for study, and culturing of hymenopteran parasitoids of the Queensland fruit fly, Bactrocera tryoni, and assesses prospects for improving biological control of this serious pest. Augmentative release of the native and naturalised Australian parasitoids, especially the braconid Diachasmimorpha tryoni, may result in better management of B. tryoni in some parts of Australia. Mass releases are an especially attractive option for areas of inland eastern Australia around the Fruit Fly Exclusion Zone that produces B. tryoni-free fruits for export. Diachasmimorpha tryoni has been successful in other locations such as Hawaii for the biological control of other fruit fly species. Biological control could contribute to local eradication of isolated outbreaks and more general suppression and/or eradication of the B. tryoni population in endemic areas. Combining biological control with the use of sterile insect technique offers scope for synergy because the former is most effective at high pest densities and the latter most economical when the pest becomes scarce. Recommendations are made on methods for culturing and study of four B. tryoni parasitoids present in Australia along with research priorities for optimising augmentative biological control of B. tryoni.

  14. Multi-objective evolutionary optimization of biological pest control with impulsive dynamics in soybean crops.

    Science.gov (United States)

    Cardoso, Rodrigo T N; da Cruz, André R; Wanner, Elizabeth F; Takahashi, Ricardo H C

    2009-08-01

    The biological pest control in agriculture, an environment-friendly practice, maintains the density of pests below an economic injury level by releasing a suitable quantity of their natural enemies. This work proposes a multi-objective numerical solution to biological pest control for soybean crops, considering both the cost of application of the control action and the cost of economic damages. The system model is nonlinear with impulsive control dynamics, in order to cope more effectively with the actual control action to be applied, which should be performed in a finite number of discrete time instants. The dynamic optimization problem is solved using the NSGA-II, a fast and trustworthy multi-objective genetic algorithm. The results suggest a dual pest control policy, in which the relative price of control action versus the associated additional harvest yield determines the usage of either a low control action strategy or a higher one.

  15. The role and control of sludge age in biological nutrient removal activated sludge systems.

    Science.gov (United States)

    Ekama, G A

    2010-01-01

    The sludge age is the most fundamental and important parameter in the design, operation and control of biological nutrient removal (BNR) activated sludge (AS) systems. Generally, the better the effluent and waste sludge quality required from the system, the longer the sludge age, the larger the biological reactor and the more wastewater characteristics need to be known. Controlling the reactor concentration does not control sludge age, only the mass of sludge in the system. When nitrification is a requirement, sludge age control becomes a requirement and the secondary settling tanks can no longer serve the dual purpose of clarifier and waste activated sludge thickeners. The easiest and most practical way to control sludge age is with hydraulic control by wasting a defined proportion of the reactor volume daily. In AS plants with reactor concentration control, nitrification fails first. With hydraulic control of sludge age, nitrification will not fail, rather the plant fails by shedding solids over the secondary settling tank effluent weirs.

  16. Control of biological hazards in cold smoked salmon production

    DEFF Research Database (Denmark)

    Huss, Hans Henrik; Embarek, Peter Karim Ben; Jeppesen, V.F.

    1995-01-01

    An outline of the common processing technology for cold smoked salmon in Denmark is presented. The safety hazards related to pathogenic bacteria, parasites and biogenic amines are discussed with special emphasis on hazards related to Clostridium botulinum and Listeria monocytogenes. Critical...... control points are identified for all hazards except growth of L. monocytogenes. For this reason a limitation of shelf life to three weeks at +5 degrees C far cold smoked vacuum-packed salmon having greater than or equal to 3% water phase salt is recommended...

  17. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France.

    Directory of Open Access Journals (Sweden)

    Thibaut Malausa

    Full Text Available Pseudococcus comstocki (Hemiptera: Pseudococcidae is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae and Acerophagus malinus (Hymenoptera: Encyrtidae. The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids.

  18. Investigating Biological Control Agents for Controlling Invasive Populations of the Mealybug Pseudococcus comstocki in France

    Science.gov (United States)

    Malausa, Thibaut; Delaunay, Mathilde; Fleisch, Alexandre; Groussier-Bout, Géraldine; Warot, Sylvie; Crochard, Didier; Guerrieri, Emilio; Delvare, Gérard; Pellizzari, Giuseppina; Kaydan, M. Bora; Al-Khateeb, Nadia; Germain, Jean-François; Brancaccio, Lisa; Le Goff, Isabelle; Bessac, Melissa; Ris, Nicolas; Kreiter, Philippe

    2016-01-01

    Pseudococcus comstocki (Hemiptera: Pseudococcidae) is a mealybug species native to Eastern Asia and present as an invasive pest in northern Italy and southern France since the start of the century. It infests apple and pear trees, grapevines and some ornamental trees. Biocontrol programmes against this pest proved successful in central Asia and North America in the second half of the 20th century. In this study, we investigated possible biocontrol agents against P. comstocki, with the aim of developing a biocontrol programme in France. We carried out systematic DNA-barcoding at each step in the search for a specialist parasitoid. First we characterised the French target populations of P. comstocki. We then identified the parasitoids attacking P. comstocki in France. Finally, we searched for foreign mealybug populations identified a priori as P. comstocki and surveyed their hymenopteran parasitoids. Three mealybug species (P. comstocki, P. viburni and P. cryptus) were identified during the survey, together with at least 16 different parasitoid taxa. We selected candidate biological control agent populations for use against P. comstocki in France, from the species Allotropa burrelli (Hymenoptera: Platygastridae) and Acerophagus malinus (Hymenoptera: Encyrtidae). The coupling of molecular and morphological characterisation for both pests and natural enemies facilitated the programme development and the rejection of unsuitable or generalist parasitoids. PMID:27362639

  19. Agricultural biological reference materials for analytical quality control

    Energy Technology Data Exchange (ETDEWEB)

    Ihnat, M.

    1986-01-01

    Cooperative work is under way at Agriculture Canada, US Department of Agriculture, and US National Bureau of Standards in an attempt to fill some of the gaps in the world repertoire of reference materials and to provide much needed control materials for laboratories' day to day operations. This undertaking involves the preparation and characterization of a number of agricultural and food materials for data quality control for inorganic constituents. Parameters considered in the development of these materials were material selection based on importance in commerce and analysis; techniques of preparation, processing, and packaging; physical and chemical characterization; homogeneity testing and quantitation (certification). A large number of agricultural/food products have been selected to represent a wide range of not only levels of sought-for constituents (elements) but also a wide range of matrix components such as protein, carbohydrate, dietary fiber, fat, and ash. Elements whose concentrations are being certified cover some two dozen major, minor, and trace elements of nutritional, toxicological, and environmental significance.

  20. Machine perception and intelligent control architecture for multirobot coordination based on biological principles

    Science.gov (United States)

    Thomopoulos, Stelios C.; Braught, Grant

    1996-10-01

    Intelligent control, inspired by biological and AI (artificial intelligence) principles, has increased the understanding of controlling complex processes without precise mathematical model of the controlled process. Through customized applications, intelligent control has demonstrated that it is a step in the right direction. However, intelligent control has yet to provide a complete solution to the problem of integrated manufacturing systems via intelligent reconfiguration of the robotics systems. The aim of this paper is to present an intelligent control architecture and design methodology based on biological principles that govern self-organization of autonomous agents. Two key structural elements of the proposed control architecture have been tested individually on key pilot applications and shown promising results. The proposed intelligent control design is inspired by observed individual and collective biological behavior in colonies of living organisms that are capable of self-organization into groups of specialized individuals capable of collectively achieving a set of prescribed or emerging objectives. The nervous and brain system in the proposed control architecture is based on reinforcement learning principles and conditioning and modeled using adaptive neurocontrollers. Mathematical control theory (e.g. optimal control, adaptive control, and neurocontrol) is used to coordinate the interactions of multiple robotics agents.

  1. Perspectives for the biological control of Cameraria ohridella.

    Science.gov (United States)

    Zemek, Rostislav; Prenerová, Eva; Volter, Lubomír; Weyda, Frantisek; Skuhravý, Václav

    2007-01-01

    The horse chestnut leaf-miner, Cameraria ohridella Deschka et Dimic (Lepidoptera, Gracillariidae) is a serious invasive pest of Aesculus hippocastanum in Europe. The larvae of this species feed on leaf parenchyma and can reduce the tree growth. We studied the impact of parasitoids on C. ohridella in the Czech Republic and also searched for entomopathogenic fungi associated with this pest. The results showed that the rate of parasitism varied between 5% and 15% in most cases. The most parasitized stages of C. ohridella were spinning stages and especially pupae. The most abundant parasitoid species were Minotetrastichus frontalis, Pnigalio sp. and Pediobius saulius (Hymenoptera, Eulophidae). All species are polyphagous. Using the Galleria-bait method we isolated many strains of entomopathogenic fungi. Dominant species were Paecilomyces fumosoroseus, Paecilomyces farinosus and Beauveria bassiana. The perspectives of fungal bioagents in control of C. ohridella is discussed. PMID:18399483

  2. Predator interference effects on biological control: The "paradox" of the generalist predator revisited

    Science.gov (United States)

    Parshad, Rana D.; Bhowmick, Suman; Quansah, Emmanuel; Basheer, Aladeen; Upadhyay, Ranjit Kumar

    2016-10-01

    An interesting conundrum in biological control questions the efficiency of generalist predators as biological control agents. Theory suggests, generalist predators are poor agents for biological control, primarily due to mutual interference. However field evidence shows they are actually quite effective in regulating pest densities. In this work we provide a plausible answer to this paradox. We analyze a three species model, where a generalist top predator is introduced into an ecosystem as a biological control, to check the population of a middle predator, that in turn is depredating on a prey species. We show that the inclusion of predator interference alone, can cause the solution of the top predator equation to blow-up in finite time, while there is global existence in the no interference case. This result shows that interference could actually cause a population explosion of the top predator, enabling it to control the target species, thus corroborating recent field evidence. Our results might also partially explain the population explosion of certain species, introduced originally for biological control purposes, such as the cane toad (Bufo marinus) in Australia, which now functions as a generalist top predator. We also show both Turing instability and spatio-temporal chaos in the model. Lastly we investigate time delay effects.

  3. Biologically inspired control of humanoid robot arms robust and adaptive approaches

    CERN Document Server

    Spiers, Adam; Herrmann, Guido

    2016-01-01

    This book investigates a biologically inspired method of robot arm control, developed with the objective of synthesising human-like motion dynamically, using nonlinear, robust and adaptive control techniques in practical robot systems. The control method caters to a rising interest in humanoid robots and the need for appropriate control schemes to match these systems. Unlike the classic kinematic schemes used in industrial manipulators, the dynamic approaches proposed here promote human-like motion with better exploitation of the robot’s physical structure. This also benefits human-robot interaction. The control schemes proposed in this book are inspired by a wealth of human-motion literature that indicates the drivers of motion to be dynamic, model-based and optimal. Such considerations lend themselves nicely to achievement via nonlinear control techniques without the necessity for extensive and complex biological models. The operational-space method of robot control forms the basis of many of the techniqu...

  4. Compatible biological and chemical control systems for Rhizoctonia solani in potato

    NARCIS (Netherlands)

    Boogert, van den P.H.J.F.; Luttikholt, A.J.G.

    2004-01-01

    A series of chemical and biological control agents were tested for compatibility with the Rhizoctonia-specific biocontrol fungus Verticillium biguttatum aimed at designing novel control strategies for black scurf (Rhizoctonia solani) and other tuber diseases in potato. The efficacy of chemicals, alo

  5. 21 CFR 310.4 - Biologics; products subject to license control.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Biologics; products subject to license control. 310.4 Section 310.4 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... to license control. (a) If a drug has an approved license under section 351 of the Public...

  6. Zika virus: History, emergence, biology, and prospects for control.

    Science.gov (United States)

    Weaver, Scott C; Costa, Federico; Garcia-Blanco, Mariano A; Ko, Albert I; Ribeiro, Guilherme S; Saade, George; Shi, Pei-Yong; Vasilakis, Nikos

    2016-06-01

    Zika virus (ZIKV), a previously obscure flavivirus closely related to dengue, West Nile, Japanese encephalitis and yellow fever viruses, has emerged explosively since 2007 to cause a series of epidemics in Micronesia, the South Pacific, and most recently the Americas. After its putative evolution in sub-Saharan Africa, ZIKV spread in the distant past to Asia and has probably emerged on multiple occasions into urban transmission cycles involving Aedes (Stegomyia) spp. mosquitoes and human amplification hosts, accompanied by a relatively mild dengue-like illness. The unprecedented numbers of people infected during recent outbreaks in the South Pacific and the Americas may have resulted in enough ZIKV infections to notice relatively rare congenital microcephaly and Guillain-Barré syndromes. Another hypothesis is that phenotypic changes in Asian lineage ZIKV strains led to these disease outcomes. Here, we review potential strategies to control the ongoing outbreak through vector-centric approaches as well as the prospects for the development of vaccines and therapeutics. PMID:26996139

  7. Biology and control of swamp dodder (Cuscuta gronovii)

    International Nuclear Information System (INIS)

    A simple model predicting swamp dodder (Cuscuta gronovii Willd.) emergence was developed. The model states that 0.1% of the cranberry seedlings will emerge after 150 to 170 GDD have accumulated after the winter ice has melted on the cranberry beds, using 0 C as the low temperature threshold. Experiments in cranberry showed that pronamide [3,5-dichloro-(N-1,1-dimethyl-2-propynyl)benzamide] was effective in controlling swamp dodder when applied preemergence. Rates below 2.4 kg ai/ha appeared to be safe for cranberry plants and fruit. Experiments with 14C glyphosate showed that the herbicide moved out of carrot leaves to the physiological sinks in the plant. In carrots parasitized by swamp dodder the dodder acted as one of the strongest sinks for photosynthates from the host. In cranberry glyphosate moved out of the leaves, but most remained in the stem to which the treated leaves were attached. The only physiological sinks that accumulated significant amounts of label were the stem apices. The concentration of the herbicide in this sink decreased with time. Swamp dodder stems were able to absorb glyphosate directly from solution

  8. OMNIHAB - a controlled environmental system for application in gravitational biology

    Science.gov (United States)

    Anken, Ralf; Hilbig, Reinhard; Anken, Ralf; Lebert, Michael; Häder, Donat

    Several "closed" habitats have been designed in the past for experiments with unicellular organisms as well as with multicellular animals and plants under long-term microgravity. Some of these environmental systems were flown successfully. The bioregenerative C.E.B.A.S.- Minimodul allowed the maintenance of higher plants (Ceratophyllum sp.), mollusks (Biomphalaria glabrata) and fish (swordtail Xiphophorus helleri, cichlid fish Oreochromis mossambicus) under spaceflight conditions (STS-89, STS-90 Neurolab, STS-107). A much simpler and smaller system, the OMEGAHAB, was successfully employed on the FOTON M-3 flight, containing cichlid fish larvae and unicellular algae (Euglena gracilis). Further aquatic habitats are under development (e.g., AquaHab, another aquatic research module especially dedicated to ground based, application-oriented research). These systems tend to be specialized, minimal ecosystems with limited research potential. Therefore, we propose to develop a controlled, multi-modular hardware to increase the diversity of experimental species to be flown together. Currently, a variety of plant and animal species are used as model systems. Combining as many of them as possible (and conducting a most effective sample-sharing among the different working groups) will strongly improve the cost-benefit ratio and thus effectiveness of a space- flight experiment in utilising limited resources at the maximum. The concept of OMNIHAB, an aquatic life support system comprising exchangeable modules, will be presented at the meeting.

  9. labelling and quality control of some 99m Tc-radiopharmaceuticals of expected biological activity

    International Nuclear Information System (INIS)

    this thesis addresses the labelling and quality control of some 99mTc-radiopharmaceuticals which could be used for infection imaging. this study focuses on the labelling of sarafloxation, gatifloxation and cefepine with technetium-99m and biological evaluation of these labeled complexes and biodistribution in both normal and inflamed mice. the thesis is organized into two chapters: chapter I :labelling of some antibiotics chapter II :biological evaluation.

  10. Modelling approach for biological control of insect pest by releasing infected pest

    Energy Technology Data Exchange (ETDEWEB)

    Tan Yuanshun [Department of Mathematics and Physics, Chongqing Jiaotong University, Chongqing 400074 (China); Department of Applied Mathematics, Dalian University of Technology, Liaoning 116024 (China)], E-mail: ystan625@yahoo.com.cn; Chen Lansun [Department of Applied Mathematics, Dalian University of Technology, Liaoning 116024 (China); Minnan Science and Technology Institute, Fujian Normal University, 362332 Fujian (China)

    2009-01-15

    Models of biological control have a long history of theoretical development that have focused on the interactions between a predator and a prey. Here we have extended the classical epidemic model to include a continuous and impulsive pest control strategies by releasing the infected pests bred in laboratory. For the continuous model, the results imply that the susceptible pest goes to extinct if the threshold condition R{sub 0} < 1. While R{sub 0} > 1, the positive equilibrium of continuous model is globally asymptotically stable. Similarly, the threshold condition which guarantees the global stability of the susceptible pest-eradication periodic solution is obtained for the model with impulsive control strategy. Consequently, based on the results obtained in this paper, the control strategies which maintain the pests below an acceptably low level are discussed by controlling the release rate and impulsive period. Finally, the biological implications of the results and the efficiency of two control strategies are also discussed.

  11. Biological control of Botrytis spp. by Ulocladium atrum : an ecological analysis

    OpenAIRE

    Kessel, G.J.T.

    1999-01-01

    Plant pathogenic fungi from the genus Botrytis cause economically important diseases in a wide range of crops during the production phase as well as post harvest phase. Control is based on the frequent use of fungicides. Alternative approaches for control are studied because of the development of fungicide resistance in the pathogen and environmental concerns.The fungal saprophytic antagonist Ulocladium atrum is an effective biological control agent of B. cinerea in cyclamen. U. atrum may als...

  12. Biological Threats

    Science.gov (United States)

    ... Workplace Plans School Emergency Plans Main Content Biological Threats Biological agents are organisms or toxins that can ... for Disease Control and Prevention . Before a Biological Threat Unlike an explosion, a biological attack may or ...

  13. Natural biological control of pest mites in Brazilian sun coffee agroecosystems.

    Science.gov (United States)

    Teodoro, Adenir V; Sarmento, Renato A; Rêgo, Adriano S; da Graça S Maciel, Anilde

    2010-06-01

    Coffee is one of the leading commodities in tropical America. Although plantations are usually established under a canopy of trees in most producing countries in the region, Brazilian coffee is mostly produced under full sun conditions. Such simple, single-crop agroecosystems with intensive agrochemical inputs often suffer with pests like mites. Predatory mites of the family Phytoseiidae are the main natural enemies associated with pest mites in the field. However, these beneficial arthropods struggle to survive in intensive agroecosystems such as coffee monocultures due to unfavorable microclimatic conditions, widespread pesticide use, and lack of alternative food (pollen, nectar). Conservation biological control uses a range of management strategies to sustain and enhance populations of indigenous natural enemies such as predatory mites. We discuss here conservation biological control as a strategy to improve biological control of pest mites by native predatory mites in Brazilian coffee monocultures as well as some related patents.

  14. Global stability and optimisation of a general impulsive biological control model

    CERN Document Server

    Mailleret, Ludovic

    2008-01-01

    An impulsive model of augmentative biological control consisting of a general continuous predator-prey model in ordinary differential equations augmented by a discrete part describing periodic introductions of predators is considered. It is shown that there exists an invariant periodic solution that corresponds to prey eradication and a condition ensuring its global asymptotic stability is given. An optimisation problem related to the preemptive use of augmentative biological control is then considered. It is assumed that the per time unit budget of biological control (i.e. the number of predators to be released) is fixed and the best deployment of this budget is sought after in terms of release frequency. The cost function to be minimised is the time taken to reduce an unforeseen prey (pest) invasion under some harmless level. The analysis shows that the optimisation problem admits a countable infinite number of solutions. An argumentation considering the required robustness of the optimisation result is the...

  15. Using consumption rate to assess potential predators for biological control of white perch

    Science.gov (United States)

    Gosch, N.J.C.; Pope, K.L.

    2011-01-01

    Control of undesirable fishes is important in aquatic systems, and using predation as a tool for biological control is an attractive option to fishery biologists. However, determining the appropriate predators for biological control is critical for success. The objective of this study was to evaluate the utility of consumption rate as an index to determine the most effective predators for biological control of an invasive fish. Consumption rate values were calculated for nine potential predators that prey on white perch Morone americana in Branched Oak and Pawnee reservoirs, Nebraska. The consumption rate index provided a unique and insightful means of determining the potential effectiveness of each predator species in controlling white perch. Cumulative frequency distributions facilitated interpretation by providing a graphical presentation of consumption rates by all individuals within each predator species. Largemouth bass Micropterus salmoides, walleye Sander vitreus and sauger S. canadensis were the most efficient white perch predators in both reservoirs; however, previous attempts to increase biomass of these predators have failed suggesting that successful biological control is unlikely using existing predator species in these Nebraska reservoirs. ?? 2011 ONEMA.

  16. Efficiacy of bumble bee disseminated biological control agents for control of Botrytis Blossom blight of Rabbiteye Blueberry

    Science.gov (United States)

    Botrytis blossom blight caused by Botrytis cinerea may cause severe crop loss in rabbiteye blueberry, necessitating applications of expensive fungicides. Commercial bumble bees, Bombus impatiens, were tested as vectors of the fungicidal biological control agents (BCAs), Prestop® Gliocladium catenula...

  17. Molecular Approach to the Nyctinastic Movement of the Plant Controlled by a Biological Clock

    Directory of Open Access Journals (Sweden)

    Shosuke Yamamura

    2001-10-01

    Full Text Available Most leguminous plants close their leaves in the evening, as if to sleep, and open them early in the morning. This circadian rhythm is known to be controlled by the biological clock of such plants. Extensive studies on other nyctinastic plants led to the isolation of a variety of leaf-closing and leaf-opening substances. And, we found that the circadian rhythmic leaf-movement of these plants is controlled by a biological clock that regulates the balance of concentration between leaf-opening and -closing substances.

  18. Biological control of invasive plant species: a reassessment for the Anthropocene.

    Science.gov (United States)

    Seastedt, Timothy R

    2015-01-01

    The science of finding, testing and releasing herbivores and pathogens to control invasive plant species has achieved a level of maturity and success that argues for continued and expanded use of this program. The practice, however, remains unpopular with some conservationists, invasion biologists, and stakeholders. The ecological and economic benefits of controlling densities of problematic plant species using biological control agents can be quantified, but the risks and net benefits of biological control programs are often derived from social or cultural rather than scientific criteria. Management of invasive plants is a 'wicked problem', and local outcomes to wicked problems have both positive and negative consequences differentially affecting various groups of stakeholders. The program has inherent uncertainties; inserting species into communities that are experiencing directional or even transformational changes can produce multiple outcomes due to context-specific factors that are further confounded by environmental change drivers. Despite these uncertainties, biological control could play a larger role in mitigation and adaptation strategies used to maintain biological diversity as well as contribute to human well-being by protecting food and fiber resources. PMID:25303317

  19. Biological control of invasive plant species: a reassessment for the Anthropocene.

    Science.gov (United States)

    Seastedt, Timothy R

    2015-01-01

    The science of finding, testing and releasing herbivores and pathogens to control invasive plant species has achieved a level of maturity and success that argues for continued and expanded use of this program. The practice, however, remains unpopular with some conservationists, invasion biologists, and stakeholders. The ecological and economic benefits of controlling densities of problematic plant species using biological control agents can be quantified, but the risks and net benefits of biological control programs are often derived from social or cultural rather than scientific criteria. Management of invasive plants is a 'wicked problem', and local outcomes to wicked problems have both positive and negative consequences differentially affecting various groups of stakeholders. The program has inherent uncertainties; inserting species into communities that are experiencing directional or even transformational changes can produce multiple outcomes due to context-specific factors that are further confounded by environmental change drivers. Despite these uncertainties, biological control could play a larger role in mitigation and adaptation strategies used to maintain biological diversity as well as contribute to human well-being by protecting food and fiber resources.

  20. The role of evolutionary biology in research and control of liver flukes in Southeast Asia.

    Science.gov (United States)

    Echaubard, Pierre; Sripa, Banchob; Mallory, Frank F; Wilcox, Bruce A

    2016-09-01

    Stimulated largely by the availability of new technology, biomedical research at the molecular-level and chemical-based control approaches arguably dominate the field of infectious diseases. Along with this, the proximate view of disease etiology predominates to the exclusion of the ultimate, evolutionary biology-based, causation perspective. Yet, historically and up to today, research in evolutionary biology has provided much of the foundation for understanding the mechanisms underlying disease transmission dynamics, virulence, and the design of effective integrated control strategies. Here we review the state of knowledge regarding the biology of Asian liver Fluke-host relationship, parasitology, phylodynamics, drug-based interventions and liver Fluke-related cancer etiology from an evolutionary biology perspective. We consider how evolutionary principles, mechanisms and research methods could help refine our understanding of clinical disease associated with infection by Liver Flukes as well as their transmission dynamics. We identify a series of questions for an evolutionary biology research agenda for the liver Fluke that should contribute to an increased understanding of liver Fluke-associated diseases. Finally, we describe an integrative evolutionary medicine approach to liver Fluke prevention and control highlighting the need to better contextualize interventions within a broader human health and sustainable development framework. PMID:27197053

  1. Enhancement of biological control agents for use against forest insect pests and diseases through biotechnology

    Science.gov (United States)

    Slavicek, James M.

    1991-01-01

    Research and development efforts in our research group are focused on the generation of more efficacious biological control agents through the techniques of biotechnology for use against forest insect pests and diseases. Effective biological controls for the gypsy moth and for tree fungal wilt pathogens are under development. The successful use of Gypchek, a formulation of the Lymantria dispar nuclear polyhedrosis virus (LdNPV), in gypsy moth control programs has generated considerable interest in that agent. As a consequence of its specificity, LdPNV has negligible adverse ecological impacts compared to most gypsy moth control agents. However, LdNPV is not competitive with other control agents in terms of cost and efficacy. We are investigating several parameters of LdNPV replication and polyhedra production in order to enhance viral potency and efficacy thus mitigating the current disadvantages of LdNPV for gypsy moth control, and have identified LdNPV variants that will facilitate these efforts. Tree endophytic bacteria that synthesize antifungal compounds were identified and an antibiotic compound from one of these bacteria was characterized. The feasibility of developing tree endophytes as biological control agents for tree vascular fungal pathogens is being investigated.

  2. Polynomial-Time Algorithm for Controllability Test of a Class of Boolean Biological Networks

    Directory of Open Access Journals (Sweden)

    Koichi Kobayashi

    2010-01-01

    Full Text Available In recent years, Boolean-network-model-based approaches to dynamical analysis of complex biological networks such as gene regulatory networks have been extensively studied. One of the fundamental problems in control theory of such networks is the problem of determining whether a given substance quantity can be arbitrarily controlled by operating the other substance quantities, which we call the controllability problem. This paper proposes a polynomial-time algorithm for solving this problem. Although the algorithm is based on a sufficient condition for controllability, it is easily computable for a wider class of large-scale biological networks compared with the existing approaches. A key to this success in our approach is to give up computing Boolean operations in a rigorous way and to exploit an adjacency matrix of a directed graph induced by a Boolean network. By applying the proposed approach to a neurotransmitter signaling pathway, it is shown that it is effective.

  3. Life cycle of Puccinia crupinae, a candidate fungal biological control agent for Crupina vulgaris

    Science.gov (United States)

    Crupina vulgaris (Common crupina, Asteraceae) is an introduced weed pest in the western United States. An isolate of the rust fungus Puccinia crupinae from the Greece is currently under evaluation as a candidate for biological control of C. crupina in a Biosafety Level 3 (BL-3) containment greenhou...

  4. Host range of the inadvertent biological control agent Caloptilia triadicae: an invasive herbivore of Chinese tallowtree

    Science.gov (United States)

    An inadvertent biological control agent of the invasive weed Chinese tallowtree (Triadica sebifera) first appeared in North America in 2004. Identified as a Caloptilia triadicae, this leaf miner was found damaging T. sebifera saplings. In Gainesville, FL we exposed naturalized populations of C. tria...

  5. Ex-ante analysis of economic returns from biological control of coconut mite in Tanzania

    NARCIS (Netherlands)

    J.M. Oleke; V. Manyong; D. Mignouna; A. Isinika; K. Mutabazi; R. Hanna; M. Sabelis

    2013-01-01

    The coconut mite, Aceria guerreronis Keifer, has been identified as one of the pests that pose a threat to the coconut industry in Benin. The study presents the simulation results of the economic benefits of the biological control of coconut mites in Benin using a standard economic surplus model. In

  6. Biological control of whitefly on greenhouse tomato in Colombia: Encarsia formosa or Amitus fuscipennis?

    NARCIS (Netherlands)

    Vis, de R.J.

    2001-01-01

    In Colombia, biological control of pests in greenhouse crops is only applied on a very limited scale in ornamentals and as yet non-existent in greenhouse vegetables. Greenhouse production of vegetables - mostly tomatoes- is a recent development, as a result of the high losses of field production due

  7. Status of biological control projects on terrestrial invasive alien weeds in California

    Science.gov (United States)

    In cooperation with foreign scientists, we are currently developing new classical biological control agents for five species of invasive alien terrestrial weeds. Cape-Ivy. A gall-forming fly, Parafreutreta regalis, and a stem-boring moth, Digitivalva delaireae, have been favorably reviewed by TAG...

  8. BIOLOGICAL CONTROL OF OLIVE FLY: BALANCING PARASITOID EFFECTIVENESS AGAINST NON-TARGET IMPACTS

    Science.gov (United States)

    Olive fly, Bactrocera oleae (Diptera: Tephritidae), has become an important pest of California olives, and is the target of a classical biological control program. We report here on the pre-release screening of imported parasitoids Hymenoptera:Braconidae), conducted in the University of California ...

  9. Economic Benefits of Advanced Control Strategies in Biological Nutrient Removal Systems

    DEFF Research Database (Denmark)

    Carstensen, J.; Nielsen, M.K.; Harremoës, Poul

    1994-01-01

    Advances in on-line monitoring of nutrient salt concentrations and computer technology has created a large potential for the implementation of advanced and complex control strategies in biological nutrient removal systems. The majority of wastewater treatment plants today are operated with very...

  10. Erroneous host identification frustrates systematics and delays implementation of biological control

    NARCIS (Netherlands)

    Bin, F.; Roversi, P.F.; Lenteren, van J.C.

    2012-01-01

    Misidentifications of pests and their natural enemies and misinterpretations of pest-natural enemy associations have led to the failure of a number of biological control projects. In addition to misidentification, more complicated kinds of errors, such as mistakes in establishing host records of par

  11. Does phylogeny explain the host choice behaviour of potential biological control agents for Brassicaceae weeds?

    Science.gov (United States)

    Four invasive Brassicaceae are currently being studied for biological control at the CABI Centre in Switzerland. A phylogenetic approach to host testing has so far been hampered by the fact that the evolutionary relationships of taxa within the Brassicaceae were unclear. Recently, a new phylogeny of...

  12. Employing spatial information technologies to monitor biological control of saltcedar in West Texas

    Science.gov (United States)

    The saltcedar leaf beetle (Diorhadha spp.) has shown promise as a biocontrol agent for saltcedar (Tamarix spp.) invasions in the United States. In Texas, natural resource managers need assistance in monitoring biological control of invasive saltcedars. This study describes application of a medium fo...

  13. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    NARCIS (Netherlands)

    de Boer, Jetske G.; Kuijper, Bram; Heimpel, George E.; Beukeboom, Leo W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding dep

  14. Low doses of ionizing radiation: Biological effects and regulatory control. Contributed papers

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency and the World Health Organization, in cooperation with the United Nations Scientific Committee on the Effects of Atomic Radiation, organized an international conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, held in seville, Spain, from 17 to 21 November 1997. This technical document contains concise papers submitted to the conference

  15. The effect of initial density and parasitoid intergenerational survival rate on classical biological control

    International Nuclear Information System (INIS)

    Models of biological control have a long history of theoretical development that have focused on the interaction of a parasitoid and its host. The host-parasitoid systems have identified several important and general factors affecting the long-term dynamics of interacting populations. However, much less is known about how the initial densities of host-parasitoid populations affect the biological control as well as the stability of host-parasitoid systems. To do this, the classical Nicholson-Bailey model with host self-regulation and parasitoid intergenerational survival rate is used to uncover the effect of initial densities on the successful biological control. The results indicate that the simplest Nicholson-Bailey model has various coexistence with a wide range of parameters, including boundary attractors where the parasitoid population is absent and interior attractors where host-parasitoid coexists. The final stable states of host-parasitoid populations depend on their initial densities as well as their ratios, and those results are confirmed by basins of attraction of initial densities. The results also indicate that the parasitoid intergenerational survival rate increases the stability of the host-parasitoid systems. Therefore, the present research can help us to further understand the dynamical behavior of host-parasitoid interactions, to improve the classical biological control and to make management decisions

  16. Biological control of Phytophthora nicotianae and organic media standardization in citrus nurseries.

    OpenAIRE

    SALEM, Assem

    2005-01-01

    Investigations were carried out for the biological control of Phytophthora nicotianae (citrus root rot) on two citrus rootstocks (Sour orange and Troyer citrange) transplanted in organic and conventional substrates, treated with the semi-commercial product Clonotri (Trichoderma harzianum and Clonostachys rosea) and Metalaxyl-M as a chemical control. Clonotri was more efficient than the chemical treatment increasing plant high and weight. Organic products (Chitosan, Quillaia, Equiseto and Clon...

  17. Variability of Botrytis cinerea sensitivity to pyrrolnitrin, an antibiotic produced by biological control agents.

    OpenAIRE

    Ajouz, Sakhr; Walker, Anne Sophie; Fabre, Frédéric; Leroux, Pierre; Nicot, Philippe; Bardin, Marc

    2011-01-01

    To establish a baseline sensitivity of Botrytis cinerea to pyrrolnitrin, an antibiotic produced by several biological control agents, 204 isolates were tested for sensitivity to pyrrolnitrin using a spore germination assay. The results showed that the isolates exhibited a wide range of sensitivity to pyrrolnitrin, with an 8.4-fold difference in EC50 (effective concentration to reduce spore germination by 50% comparing to the control) values between the least and the most sensitive isolates. T...

  18. Biological control of pests in protected cultivation: implementation in Latin America and successes in Europe

    OpenAIRE

    Bueno, V.H.P.; Lenteren, van, J.C.

    2010-01-01

    The area with greenhouse crops is estimated to be around 40,000 hectares in Latin America, of which approximately 60% is occupied with ornamentals. Several pests are responsible for losses in yield or quality of greenhouse crops production and pest control is still mainly by chemicals. However, there are several stimuli for the adoption of biological control strategies as an IPM component, not only for the export market of products, but also for increased use of sustainable plant protection m...

  19. Biological and social influences on cognitive control processes dependent on prefrontal cortex

    OpenAIRE

    Diamond, Adele

    2011-01-01

    Cognitive control functions (“executive functions” [EFs] such as attentional control, self-regulation, working memory, and inhibition) that depend on prefrontal cortex (PFC) are critical for success in school and in life. Many children begin school lacking needed EF skills. Disturbances in EFs occur in many mental health disorders, such as ADHD and depression. This chapter addresses modulation of EFs by biology (genes and neurochemistry) and the environment (including school programs) with im...

  20. The state of commercial augmentative biological control: plenty of natural enemies, but a frustrating lack of uptake

    NARCIS (Netherlands)

    Lenteren, van J.C.

    2012-01-01

    Augmentative biological control concerns the periodical release of natural enemies. In com- mercial augmentative biological control, natural enemies are mass-reared in biofactories for release in large numbers to obtain an immediate control of pests. The history of commercial mass production of natu

  1. Do biological-based strategies hold promise to biofouling control in MBRs?

    KAUST Repository

    Malaeb, Lilian

    2013-10-01

    Biofouling in membrane bioreactors (MBRs) remains a primary challenge for their wider application, despite the growing acceptance of MBRs worldwide. Research studies on membrane fouling are extensive in the literature, with more than 200 publications on MBR fouling in the last 3 years; yet, improvements in practice on biofouling control and management have been remarkably slow. Commonly applied cleaning methods are only partially effective and membrane replacement often becomes frequent. The reason for the slow advancement in successful control of biofouling is largely attributed to the complex interactions of involved biological compounds and the lack of representative-for-practice experimental approaches to evaluate potential effective control strategies. Biofouling is driven by microorganisms and their associated extra-cellular polymeric substances (EPS) and microbial products. Microorganisms and their products convene together to form matrices that are commonly treated as a black box in conventional control approaches. Biological-based antifouling strategies seem to be a promising constituent of an effective integrated control approach since they target the essence of biofouling problems. However, biological-based strategies are in their developmental phase and several questions should be addressed to set a roadmap for translating existing and new information into sustainable and effective control techniques. This paper investigates membrane biofouling in MBRs from the microbiological perspective to evaluate the potential of biological-based strategies in offering viable control alternatives. Limitations of available control methods highlight the importance of an integrated anti-fouling approach including biological strategies. Successful development of these strategies requires detailed characterization of microorganisms and EPS through the proper selection of analytical tools and assembly of results. Existing microbiological/EPS studies reveal a number of

  2. Do biological-based strategies hold promise to biofouling control in MBRs?

    Science.gov (United States)

    Malaeb, Lilian; Le-Clech, Pierre; Vrouwenvelder, Johannes S; Ayoub, George M; Saikaly, Pascal E

    2013-10-01

    Biofouling in membrane bioreactors (MBRs) remains a primary challenge for their wider application, despite the growing acceptance of MBRs worldwide. Research studies on membrane fouling are extensive in the literature, with more than 200 publications on MBR fouling in the last 3 years; yet, improvements in practice on biofouling control and management have been remarkably slow. Commonly applied cleaning methods are only partially effective and membrane replacement often becomes frequent. The reason for the slow advancement in successful control of biofouling is largely attributed to the complex interactions of involved biological compounds and the lack of representative-for-practice experimental approaches to evaluate potential effective control strategies. Biofouling is driven by microorganisms and their associated extra-cellular polymeric substances (EPS) and microbial products. Microorganisms and their products convene together to form matrices that are commonly treated as a black box in conventional control approaches. Biological-based antifouling strategies seem to be a promising constituent of an effective integrated control approach since they target the essence of biofouling problems. However, biological-based strategies are in their developmental phase and several questions should be addressed to set a roadmap for translating existing and new information into sustainable and effective control techniques. This paper investigates membrane biofouling in MBRs from the microbiological perspective to evaluate the potential of biological-based strategies in offering viable control alternatives. Limitations of available control methods highlight the importance of an integrated anti-fouling approach including biological strategies. Successful development of these strategies requires detailed characterization of microorganisms and EPS through the proper selection of analytical tools and assembly of results. Existing microbiological/EPS studies reveal a number of

  3. Cardiocladius oliffi (Diptera: Chironomidae as a potential biological control agent against Simulium squamosum (Diptera: Simuliidae

    Directory of Open Access Journals (Sweden)

    Wilson Michael D

    2009-04-01

    Full Text Available Abstract Background The control of onchocerciasis in the African region is currently based mainly on the mass drug administration of ivermectin. Whilst this has been found to limit morbidity, it does not stop transmission. In the absence of a macrofilaricide, there is a need for an integrated approach for disease management, which includes vector control. Vector control using chemical insecticides is expensive to apply, and therefore the use of other measures such as biological control agents is needed. Immature stages of Simulium squamosum, reared in the laboratory from egg masses collected from the field at Boti Falls and Huhunya (River Pawnpawn in Ghana, were observed to be attacked and fed upon by larvae of the chironomid Cardiocladius oliffi Freeman, 1956 (Diptera: Chironomidae. Methods Cardiocladius oliffi was successfully reared in the rearing system developed for S. damnosum s.l. and evaluated for its importance as a biological control agent in the laboratory. Results Even at a ratio of one C. oliffi to five S. squamosum, they caused a significant decrease in the number of adult S. squamosum emerging from the systems (treatments. Predation was confirmed by the amplification of Simulium DNA from C. oliffi observed to have fed on S. squamosum pupae. The study also established that the chironomid flies could successfully complete their development on a fish food diet only. Conclusion Cardiocladius oliffi has been demonstrated as potential biological control agent against S. squamosum.

  4. Imposing early stability to ecological and biological networks through Evolutionary Network Control

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2015-03-01

    Full Text Available The stability analysis of the dynamical networks is a well-studied topic, both in ecology and in biology. In this work, I adopt a different perspective: instead of analysing the stability of an arbitrary ecological network, I seek here to impose such stability as soon as possible (or, contrariwise, as late as possible during network dynamics. Evolutionary Network Control (ENC is a theoretical and methodological framework aimed to the control of ecological and biological networks by coupling network dynamics and evolutionary modelling. ENC covers several topics of network control, for instance a the global control from inside and b from outside, c the local (step-by-step control, and the computation of: d control success, e feasibility, and f degree of uncertainty. In this work, I demonstrate that ENC can also be employed to impose early (but, also, late stability to arbitrary ecological and biological networks, and provide an applicative example based on the nonlinear, widely-used, Lotka-Volterra model.

  5. Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

    Science.gov (United States)

    Williams, Wyatt I.; Friedman, Jonathan M.; Gaskin, John F.; Norton, Andrew P.

    2014-01-01

    Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western United States, and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Increased levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpins the importance of plant hybridization and may explain why some biological control releases are more successful than others.

  6. Biological control of fruit flies (Diptera: Tephritidae) through parasitoid augmentative releases: Current status

    International Nuclear Information System (INIS)

    Fruit flies are among the main pests affecting the world fruit industry (Aluja 1993). Bait sprays have traditionally been used successfully to control them; however, the side effects on the environment and health hazards commonly associated with pesticides, have resulted in strong public opposition to the use of bait sprays. This is particularly so when sprays are applied in urban areas or in coffee plantations where, although Medflies are present, they do not pose a danger to crops. Alternative methods that are effective and environmental friendly to suppress fruit fly populations are highly desirable. Biological control, the use of natural enemies to suppress pest populations, represents such an alternative. Some of the most successful cases of biological control are the control of Iceria purchasi Maskell (Homoptera: Margarodidae) by Rodolia cardinalis Mulsant (Coleoptera: Coccinellidae) in California (De Bach 1968, van den Bosch et al. 1982), and the control of Aleurocanthus woglumi Ashby (Homoptera: Aleyrodidae) mainly by Encarsia (=Prospaltella) opulenta Silv. (Hymenoptera: Aphelinidae) in Mexico (Jimenez 1961, 1971), both using the classical approach. However, this approach has been limited to certain conditions of environmental stability and biodiversity which are only found in a few ecosystems. Other factors, such as types of pests, the economic threshold and product quality requirements represent additional limitations. The best option in many cases could be augmentative biological control, which could overcome some of the deficiencies of the classical approach (Sivinski 1996). According to Knipling (1992) and Barclay (1987), augmentative biological control can be considered as a formal alternative for suppressing pest populations and even for use in eradication programmes, after integration with the sterile insect technique (SIT). In this approach, mass production of natural enemies is required and this production has to be cost effective

  7. Biological control of Ixodes ricinus larvae and nymphs with Metarhizium anisopliae blastospores.

    Science.gov (United States)

    Wassermann, Marion; Selzer, Philipp; Steidle, Johannes L M; Mackenstedt, Ute

    2016-07-01

    The entomopathogenic fungus Metarhizium anisopliae is used as a biological pest control agent against various arthropod species, including ticks. However, the efficacy depends on tick species, tick stage and fungus strain. We studied the effect of M. anisopliae on engorged larvae and nymphs of Ixodes ricinus, the most abundant tick species in Europe, under laboratory and semi-field conditions. A significant reduction of engorged larvae and nymphs could be shown under laboratory as well as under semi-field conditions. Only 3.5% of the larvae treated in the lab and only 18.5% kept under semi-field conditions were able to develop into nymphs compared to the recovered nymphs of the control groups, which were regarded as 100%. Only 7.1% of nymphs were recovered as adult ticks after fungal treatment under semi-field conditions compared to the control (100%). The efficacy of blastospores of M. anisopliae against engorged larvae and nymphs of I. ricinus under semi-field conditions was demonstrated in this study, showing their high potential as a biological control agent of ticks. Further studies will have to investigate the effect of this agent against other stages of I. ricinus as well as other tick species before its value as a biological control agent against ticks can be fully assessed.

  8. The Google matrix controls the stability of structured ecological and biological networks

    Science.gov (United States)

    Stone, Lewi

    2016-09-01

    May's celebrated theoretical work of the 70's contradicted the established paradigm by demonstrating that complexity leads to instability in biological systems. Here May's random-matrix modelling approach is generalized to realistic large-scale webs of species interactions, be they structured by networks of competition, mutualism or both. Simple relationships are found to govern these otherwise intractable models, and control the parameter ranges for which biological systems are stable and feasible. Our analysis of model and real empirical networks is only achievable on introducing a simplifying Google-matrix reduction scheme, which in the process, yields a practical ecological eigenvalue stability index. These results provide an insight into how network topology, especially connectance, influences species stable coexistence. Constraints controlling feasibility (positive equilibrium populations) in these systems are found more restrictive than those controlling stability, helping explain the enigma of why many classes of feasible ecological models are nearly always stable.

  9. Commercial Biological Control Agents Targeted Against Plant-Parasitic Root-knot Nematodes

    Directory of Open Access Journals (Sweden)

    Marie-Stéphane Tranier

    2014-12-01

    Full Text Available Root-knot nematodes are microscopic round worms, which cause severe agricultural losses. Their attacks affect the productivity by reducing the amount and the caliber of the fruits. Chemical control is widely used, but biological control appears to be a better solution, mainly using microorganisms to reduce the quantity of pests infecting crops. Biological control is developing gradually, and with time, more products are being marketed worldwide. They can be formulated with bacteria, viruses or with filamentous fungi, which can destroy and feed on phytoparasitic nematodes. To be used by the farmers, biopesticides must be legalized by the states, which has led to the establishment of a legal framework for their use, devised by various governmental organizations.

  10. Alternative stable states explain unpredictable biological control of Salvinia molesta in Kakadu.

    Science.gov (United States)

    Schooler, Shon S; Salau, Buck; Julien, Mic H; Ives, Anthony R

    2011-02-01

    Suppression of the invasive plant Salvinia molesta by the salvinia weevil is an iconic example of successful biological control. However, in the billabongs (oxbow lakes) of Kakadu National Park, Australia, control is fitful and incomplete. By fitting a process-based nonlinear model to thirteen-year data sets from four billabongs, here we show that incomplete control can be explained by alternative stable states--one state in which salvinia is suppressed and the other in which salvinia escapes weevil control. The shifts between states are associated with annual flooding events. In some years, high water flow reduces weevil populations, allowing the shift from a controlled to an uncontrolled state; in other years, benign conditions for weevils promote the return shift to the controlled state. In most described ecological examples, transitions between alternative stable states are relatively rare, facilitated by slow-moving environmental changes, such as accumulated nutrient loading or climate change. The billabongs of Kakadu give a different manifestation of alternative stable states that generate complex and seemingly unpredictable dynamics. Because shifts between alternative stable states are stochastic, they present a potential management strategy to maximize effective biological control: when the domain of attraction to the state of salvinia control is approached, augmentation of the weevil population or reduction of the salvinia biomass may allow the lower state to trap the system. PMID:21293376

  11. Biological control against the carob moth Ectomyelois ceratoniae in oases and in packing houses in Tunisia

    International Nuclear Information System (INIS)

    The carob moth, Ectomyelois ceratoniae Zeller is abundant in the Mediterranean countries. It attacks various dry fruit in cultures or in stored products, notably pomegranate, Punica granatum L.; date palm, Phoenis dactylifera L. plantations; citrus, Citrus spp., apricot, Prunus armeniaca L. and pistachios, Pistachio vera. We can find E. ceratoniae in the north as well as in the south of Tunisia, especially in central zones and Saharan areas where caterpillar infestations can reach 90% of pomegranate fruit and 20% of dates (Dhouibi 1991). To reduce this damage, several control methods have been experimented. Chemical control is the most effective means of control against pests. However, against this species, insecticides seem to be difficult and randomly used, due to the endophytic behaviour of the pyralid and the position of the fruit on the pomegranate tree. Moreover, this method has very ominous repercussions on biological cadence. Besides, it is necessary to look for other control means to allow the preservation of the ecosystem. In Tunisia, several efforts have been directed at biological control, by using local parasitoids and through usage of the bio-insecticides mainly Bacillus thuringiensis (Dhouibi 1992, 1994, Dhouibi and Jemmasi 1993). In order to substitute the chemical control and to strengthen the integrated control, other possibilities can be envisaged, for example, the genetic method or the autocidal control, that is, based on mass rearing and the substerile male releases into the natural population. For the purpose, it provokes the sterility to ulterior generations and evaluates the impact of irradiation on the different biological parameters of emerged adults from treated nymphs and their competitiveness. Dhouibi and Omran (1995) and Dhouibi and Tijani (1996) have studied the mass rearing of the carob moth pyralid on an artificial diet and the effect of different irradiation doses, especially a substerilising dose, on E. ceratoniae pupae

  12. Safety of biologics in rheumatoid arthritis: data from randomized controlled trials and registries

    Directory of Open Access Journals (Sweden)

    Codreanu C

    2015-01-01

    Full Text Available Catalin O Codreanu,1 Nemanja Damjanov2 1Rheumatology Department, Center of Rheumatic Diseases, Bucharest, Romania; 2Institute of Rheumatology, School of Medicine, University of Belgrade, Belgrade, SerbiaAbstract: Over the past decade, the use of biologics has significantly changed the management of rheumatoid arthritis (RA. Biologics selectively target components of the immune system, resulting in better disease control. However, the growing use of biologics in RA has increased safety concerns among rheumatologists. Randomized controlled trials (RCTs and registries are the most reliable sources of clinical safety data. Although safety data from RCTs provide certain insights into the clinical safety profile of an agent, strict constraints in study design (eg, exclusion criteria and restrictive treatment protocols often do not accurately reflect possible safety issues in the use of the agent, either in the clinical setting or over long-term treatment. Registries, on the other hand, are not restrictive regarding patient enrollment, making them more reliable in evaluating long-term safety. A number of registries have been established globally: in Europe, the United States, and Asia. However, the availability of registry data from Eastern Europe is lacking. The notable exceptions so far are registries from the Czech Republic (ATTRA, a registry of patients treated with anti-tumor necrosis factor-alpha drugs and Serbia (National registry of patients with rheumatoid arthritis in Serbia [NARRAS]. The current report provides an overview of safety data with biologics in RA from RCTs and registries. Availability of regional safety data from Eastern Europe is of great importance to its clinicians for making evidence-based treatment decisions in RA. Keywords: biologic therapy, biologic drugs, adverse events, infections, pregnancy, malignancies

  13. Adhesion control by inflation: implications from biology to artificial attachment device

    Science.gov (United States)

    Dening, Kirstin; Heepe, Lars; Afferrante, Luciano; Carbone, Giuseppe; Gorb, Stanislav N.

    2014-08-01

    There is an increasing demand for materials that incorporate advanced adhesion properties, such as an ability to adhere in a reversible and controllable manner. In biological systems, these features are known from adhesive pads of the tree frog, Litoria caerulea, and the bush-cricket, Tettigonia viridissima. These species have convergently developed soft, hemispherically shaped pads that might be able to control their adhesion through active changing the curvature of the pad. Inspired by these biological systems, an artificial model system is developed here. It consists of an inflatable membrane clamped to the metallic cylinder and filled with air. Pull-off force measurements of the membrane surface were conducted in contact with the membrane at five different radii of curvature r c with (1) a smooth polyvinylsiloxane membrane and (2) mushroom-shaped adhesive microstructured membrane made of the same polymer. The hypothesis that an increased internal pressure, acting on the membrane, reduces the radius of the membrane curvature, resulting in turn in a lower pull-off force, is verified. Such an active control of adhesion, inspired by biological models, will lead to the development of industrial pick-and-drop devices with controllable adhesive properties.

  14. Is ground cover vegetation an effective biological control enhancement strategy against olive pests?

    Directory of Open Access Journals (Sweden)

    Daniel Paredes

    Full Text Available Ground cover vegetation is often added or allowed to generate to promote conservation biological control, especially in perennial crops. Nevertheless, there is inconsistent evidence of its effectiveness, with studies reporting positive, nil or negative effects on pest control. This might arise from differences between studies at the local scale (e.g. orchard management and land use history, the landscape context (e.g. presence of patches of natural or semi-natural vegetation near the focal orchard, or regional factors, particularly climate in the year of the study. Here we present the findings from a long-term regional monitoring program conducted on four pest species (Bactrocera oleae, Prays oleae, Euphyllura olivina, Saissetia oleae in 2,528 olive groves in Andalusia (Spain from 2006 to 2012. Generalized linear mixed effect models were used to analyze the effect of ground cover on different response variables related to pest abundance, while accounting for variability at the local, landscape and regional scales. There were small and inconsistent effects of ground cover on the abundance of pests whilst local, landscape and regional variability explained a large proportion of the variability in pest response variables. This highlights the importance of local and landscape-related variables in biological control and the potential effects that might emerge from their interaction with practices, such as groundcover vegetation, implemented to promote natural enemy activity. The study points to perennial vegetation close to the focal crop as a promising alternative strategy for conservation biological control that should receive more attention.

  15. Conservation biological control of pests in the molecular era: new opportunities to address old constraints

    Directory of Open Access Journals (Sweden)

    Gurr eGeoff

    2016-01-01

    Full Text Available ABSTRACTBiological control has long been considered a potential alternative to pesticidal strategies for pest management but its impact and level of use globally remain modest and inconsistent. A rapidly expanding range of molecular – particularly DNA-related – techniques is currently revolutionizing many life sciences. This review identifies a series of constraints on the development and uptake of conservation biological control and considers the contemporary and likely future influence of molecular methods on these constraints. Molecular approaches are now often used to complement morphological taxonomic methods for the identification and study of biological control agents including microbes. A succession of molecular techniques has been applied to ‘who eats whom’ questions in food-web ecology. Polymerase chain reaction (PCR approaches have largely superseded immunological approaches such as enzyme-linked immunosorbent assay (ELISA and now – in turn – are being overtaken by next generation sequencing (NGS- based approaches that offer unparalleled power at a rapidly diminishing cost. There is scope also to use molecular techniques to manipulate biological control agents, which will be accelerated with the advent of gene editing tools, the CRISPR/Cas9 system in particular. Gene editing tools also offer unparalleled power to both elucidate and manipulate the plant defence mechanisms including those that involve natural enemy attraction to attacked plants. Rapid advances in technology will allow the development of still more novel pest management options for which uptake is likely to be limited chiefly by regulatory hurdles.

  16. Guiding Classical Biological Control of an Invasive Mealybug Using Integrative Taxonomy.

    Directory of Open Access Journals (Sweden)

    Aleixandre Beltrà

    Full Text Available Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae is a mealybug of Southern African origin that has recently been introduced into Eastern Spain. It causes severe distortions on young citrus fruits and represents a growing threat to Mediterranean citrus production. So far, biological control has proven unsatisfactory due to the absence of efficient natural enemies in Spain. Hence, the management of this pest currently relies only on chemical control. The introduction of natural enemies of D. aberiae from the native area of the pest represents a sustainable and economically viable alternative to reduce the risks linked to pesticide applications. Since biological control of mealybugs has been traditionally challenged by taxonomic misidentification, an intensive survey of Delottococcus spp. and their associated parasitoids in South Africa was required as a first step towards a classical biological control programme. Combining morphological and molecular characterization (integrative taxonomy a total of nine mealybug species were identified in this study, including three species of Delottococcus. Different populations of D. aberiae were found on wild olive trees, in citrus orchards and on plants of Chrysanthemoides monilifera, showing intra-specific divergences according to their host plants. Interestingly, the invasive mealybug populations from Spanish orchards clustered together with the population on citrus from Limpopo Province (South Africa, sharing COI haplotypes. This result pointed to an optimum location to collect natural enemies against the invasive mealybug. A total of 14 parasitoid species were recovered from Delottococcus spp. and identified to genus and species level, by integrating morphological and molecular data. A parasitoid belonging to the genus Anagyrus, collected from D. aberiae in citrus orchards in Limpopo, is proposed here as a good biological control agent to be introduced into Spain.

  17. Guiding Classical Biological Control of an Invasive Mealybug Using Integrative Taxonomy

    Science.gov (United States)

    Beltrà, Aleixandre; Addison, Pia; Ávalos, Juan Antonio; Crochard, Didier; Garcia-Marí, Ferran; Guerrieri, Emilio; Giliomee, Jan H.; Malausa, Thibaut; Navarro-Campos, Cristina; Palero, Ferran; Soto, Antonia

    2015-01-01

    Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae) is a mealybug of Southern African origin that has recently been introduced into Eastern Spain. It causes severe distortions on young citrus fruits and represents a growing threat to Mediterranean citrus production. So far, biological control has proven unsatisfactory due to the absence of efficient natural enemies in Spain. Hence, the management of this pest currently relies only on chemical control. The introduction of natural enemies of D. aberiae from the native area of the pest represents a sustainable and economically viable alternative to reduce the risks linked to pesticide applications. Since biological control of mealybugs has been traditionally challenged by taxonomic misidentification, an intensive survey of Delottococcus spp. and their associated parasitoids in South Africa was required as a first step towards a classical biological control programme. Combining morphological and molecular characterization (integrative taxonomy) a total of nine mealybug species were identified in this study, including three species of Delottococcus. Different populations of D. aberiae were found on wild olive trees, in citrus orchards and on plants of Chrysanthemoides monilifera, showing intra-specific divergences according to their host plants. Interestingly, the invasive mealybug populations from Spanish orchards clustered together with the population on citrus from Limpopo Province (South Africa), sharing COI haplotypes. This result pointed to an optimum location to collect natural enemies against the invasive mealybug. A total of 14 parasitoid species were recovered from Delottococcus spp. and identified to genus and species level, by integrating morphological and molecular data. A parasitoid belonging to the genus Anagyrus, collected from D. aberiae in citrus orchards in Limpopo, is proposed here as a good biological control agent to be introduced into Spain. PMID:26047349

  18. Guiding Classical Biological Control of an Invasive Mealybug Using Integrative Taxonomy.

    Science.gov (United States)

    Beltrà, Aleixandre; Addison, Pia; Ávalos, Juan Antonio; Crochard, Didier; Garcia-Marí, Ferran; Guerrieri, Emilio; Giliomee, Jan H; Malausa, Thibaut; Navarro-Campos, Cristina; Palero, Ferran; Soto, Antonia

    2015-01-01

    Delottococcus aberiae De Lotto (Hemiptera: Pseudococcidae) is a mealybug of Southern African origin that has recently been introduced into Eastern Spain. It causes severe distortions on young citrus fruits and represents a growing threat to Mediterranean citrus production. So far, biological control has proven unsatisfactory due to the absence of efficient natural enemies in Spain. Hence, the management of this pest currently relies only on chemical control. The introduction of natural enemies of D. aberiae from the native area of the pest represents a sustainable and economically viable alternative to reduce the risks linked to pesticide applications. Since biological control of mealybugs has been traditionally challenged by taxonomic misidentification, an intensive survey of Delottococcus spp. and their associated parasitoids in South Africa was required as a first step towards a classical biological control programme. Combining morphological and molecular characterization (integrative taxonomy) a total of nine mealybug species were identified in this study, including three species of Delottococcus. Different populations of D. aberiae were found on wild olive trees, in citrus orchards and on plants of Chrysanthemoides monilifera, showing intra-specific divergences according to their host plants. Interestingly, the invasive mealybug populations from Spanish orchards clustered together with the population on citrus from Limpopo Province (South Africa), sharing COI haplotypes. This result pointed to an optimum location to collect natural enemies against the invasive mealybug. A total of 14 parasitoid species were recovered from Delottococcus spp. and identified to genus and species level, by integrating morphological and molecular data. A parasitoid belonging to the genus Anagyrus, collected from D. aberiae in citrus orchards in Limpopo, is proposed here as a good biological control agent to be introduced into Spain. PMID:26047349

  19. Safety of biologics in rheumatoid arthritis: data from randomized controlled trials and registries.

    Science.gov (United States)

    Codreanu, Catalin; Damjanov, Nemanja

    2015-01-01

    Over the past decade, the use of biologics has significantly changed the management of rheumatoid arthritis (RA). Biologics selectively target components of the immune system, resulting in better disease control. However, the growing use of biologics in RA has increased safety concerns among rheumatologists. Randomized controlled trials (RCTs) and registries are the most reliable sources of clinical safety data. Although safety data from RCTs provide certain insights into the clinical safety profile of an agent, strict constraints in study design (eg, exclusion criteria and restrictive treatment protocols) often do not accurately reflect possible safety issues in the use of the agent, either in the clinical setting or over long-term treatment. Registries, on the other hand, are not restrictive regarding patient enrollment, making them more reliable in evaluating long-term safety. A number of registries have been established globally: in Europe, the United States, and Asia. However, the availability of registry data from Eastern Europe is lacking. The notable exceptions so far are registries from the Czech Republic (ATTRA, a registry of patients treated with anti-tumor necrosis factor-alpha drugs) and Serbia (National registry of patients with rheumatoid arthritis in Serbia [NARRAS]). The current report provides an overview of safety data with biologics in RA from RCTs and registries. Availability of regional safety data from Eastern Europe is of great importance to its clinicians for making evidence-based treatment decisions in RA. PMID:25670881

  20. 77 FR 46373 - Field Release of Aphelinus glycinis for the Biological Control of the Soybean Aphid in the...

    Science.gov (United States)

    2012-08-03

    ... the Biological Control of the Soybean Aphid in the Continental United States; Availability of an... release of Aphelinus glycinis for the biological control of the soybean aphid, Aphis glycines, in the...-2323. SUPPLEMENTARY INFORMATION: Background The soybean aphid, Aphis glycinis, which is native to...

  1. Development of biological control of Tetranychus urticae (Acari:Tetranychidae) and Phorodon humuli (Hemiptera: Aphididae) in Oregon Hop yards

    Science.gov (United States)

    The temporal development of biological control of arthropod pests in perennial cropping systems is largely unreported. In this study, the development of biological control of twospotted spider mite, Tetranychus urticae Koch and hop aphid, Phorodon humuli (Schrank) in a new planting of hop in Oregon...

  2. The influence of flower morphology and nectar quality on the longevity of a parasitoid biological control agent

    NARCIS (Netherlands)

    Vattala, H.D.; Wratten, S.D.; Phillips, C.B.; Wäckers, F.L.

    2006-01-01

    Conservation biological control aims to enhance the efficacy of arthropod biological control agents, such as parasitoids, partly by providing them with access to floral nectar. However, the suitability of a flower species for providing nectar to a parasitoid is dependent on the morphologies of the p

  3. Biologically Inspired Modular Neural Control for a Leg-Wheel Hybrid Robot

    DEFF Research Database (Denmark)

    Manoonpong, Poramate; Wörgötter, Florentin; Laksanacharoen, Pudit

    2014-01-01

    In this article we present modular neural control for a leg-wheel hybrid robot consisting of three legs with omnidirectional wheels. This neural control has four main modules having their functional origin in biological neural systems. A minimal recurrent control (MRC) module is for sensory signal...... processing and state memorization. Its outputs drive two front wheels while the rear wheel is controlled through a velocity regulating network (VRN) module. In parallel, a neural oscillator network module serves as a central pattern generator (CPG) controls leg movements for sidestepping. Stepping directions...... is developed and tested using a physics simulation environment. This study verifies that the neural modules can serve a general purpose regardless of the robot’s specific embodiment. We also believe that our neural modules can be important components for locomotion generation in other complex robotic systems...

  4. Climate warming increases biological control agent impact on a non-target species.

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species.

  5. Climate warming increases biological control agent impact on a non-target species

    Science.gov (United States)

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2015-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising temperature and plant life history changed from perennial to annual. Experiments showed that elevated temperature changed plant life history and increased insect overwintering, damage and impacts on seedling recruitment. These results suggest that warming can shift phenologies, increase non-target effect magnitude and increase non-target effect occurrence by beetle range expansion to additional areas where A. sessilis occurs. This study highlights the importance of understanding how climate change affects species interactions for future biological control of invasive species and conservation of native species. PMID:25376303

  6. Preliminary Study on Biological Control of Cyclops of Zooplankton in Drinking Water Source

    Institute of Scientific and Technical Information of China (English)

    刘冬梅; 崔福义; 林涛; 张立秋

    2004-01-01

    An ecological project called fish biomanipulation, other than the conventional fishery culture technique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of four species of fish were investigated experimentally at stocking density of 30 g per cubic meter of water. The experimental results showed that the food habit of the fish had significant influence on the biological control of Cyclops. The propagation of Cyclops could be controlled effectively and also the water quality was improved simultaneously by stocking the filter-feeding fishes, such as silver carp and bighead carp. Whereas, herbivorous Ctenopharyngodon idellus and omnivorous Cyprinus carpio had no obvious biological effects on controlling the growth of Cyclops and restoring water quality. The results further proved that under condition of proper poly-culture density of silver carp and bighead carp, the number of Cyclops might be controlled at very low level and the eutrophication might be abated by removing the nutrients from water body.

  7. A novel control strategy for efficient biological phosphorus removal with carbon-limited wastewaters.

    Science.gov (United States)

    Guerrero, Javier; Guisasola, Albert; Baeza, Juan A

    2014-01-01

    This work shows the development and the in silico evaluation of a novel control strategy aiming at successful biological phosphorus removal in a wastewater treatment plant operating in an A(2)/O configuration with carbon-limited influent. The principle of this novel approach is that the phosphorus in the effluent can be controlled with the nitrate setpoint in the anoxic reactor as manipulated variable. The theoretical background behind this control strategy is that reducing nitrate entrance to the anoxic reactor would result in more organic matter available for biological phosphorus removal. Thus, phosphorus removal would be enhanced at the expense of increasing nitrate in the effluent (but always below legal limits). The work shows the control development, tuning and performance in comparison to open-loop conditions and to two other conventional control strategies for phosphorus removal based on organic matter and metal addition. It is shown that the novel proposed strategy achieves positive nutrient removal results with similar operational costs to the other control strategies and open-loop operation. PMID:25116500

  8. A simulation benchmark to evaluate the performance of advanced control techniques in biological wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Sotomayor O.A.Z.

    2001-01-01

    Full Text Available Wastewater treatment plants (WWTP are complex systems that incorporate a large number of biological, physicochemical and biochemical processes. They are large and nonlinear systems subject to great disturbances in incoming loads. The primary goal of a WWTP is to reduce pollutants and the second goal is disturbance rejection, in order to obtain good effluent quality. Modeling and computer simulations are key tools in the achievement of these two goals. They are essential to describe, predict and control the complicated interactions of the processes. Numerous control techniques (algorithms and control strategies (structures have been suggested to regulate WWTP; however, it is difficult to make a discerning performance evaluation due to the nonuniformity of the simulated plants used. The main objective of this paper is to present a benchmark of an entire biological wastewater treatment plant in order to evaluate, through simulations, different control techniques. This benchmark plays the role of an activated sludge process used for removal of organic matter and nitrogen from domestic effluents. The development of this simulator is based on models widely accepted by the international community and is implemented in Matlab/Simulink (The MathWorks, Inc. platform. The benchmark considers plant layout and the effects of influent characteristics. It also includes a test protocol for analyzing the open and closed-loop responses of the plant. Examples of control applications in the benchmark are implemented employing conventional PI controllers. The following common control strategies are tested: dissolved oxygen (DO concentration-based control, respirometry-based control and nitrate concentration-based control.

  9. Recent Advances in Biological Control of Pest Insects by Using Viruses in China

    Institute of Scientific and Technical Information of China (English)

    Xiu-lian SUN; Hui-yin PENG

    2007-01-01

    Insect viruses are attractive as biological control agents and could be a feasible alternative to chemical insecticides in the management of insect infestations. This review describes recent advances in the development of wild-type and genetically modified viruses as insecticides. A new strategy of application of insect viruses in China is reviewed. Also, the assessment of biosafety of genetically modified Helicoverpa armigera Nucleopolyhedovirus (HearNPV) is emphasized as a case-study.

  10. Biological and chemical treatment of Cedrela fissilis seeds for controlling Rhizoctonia sp.

    OpenAIRE

    Marília Lazarotto; Marlove Fátima Brião Muniz; Rafael Beltrame; Álvaro Figueredo dos Santos; Jucéli Müller; Maristela Machado Araújo

    2013-01-01

    This research evaluated the effect of a fungicide and a biological product, singly and combined, for the control of pathogens, especially Rhizoctonia sp., in seeds of Cedrela fissilis. Before the seeds treatment, the inoculation of Rhizoctonia sp., isolated from C. fissilis seeds in blotter-test and considered pathogenic for the specie, was done on half of the seeds used. After, the seeds were subjected to treatments with powder organic product based on Trichoderma spp. (singly), powder fungi...

  11. Biologically inspired kinematic synergies enable linear balance control of a humanoid robot

    OpenAIRE

    Hauser, Helmut; Neumann, Gerhard; Ijspeert, Auke J.; Maass, Wolfgang

    2011-01-01

    Despite many efforts, balance control of humanoid robots in the presence of unforeseen external or internal forces has remained an unsolved problem. The difficulty of this problem is a consequence of the high dimensionality of the action space of a humanoid robot, due to its large number of degrees of freedom (joints), and of non-linearities in its kinematic chains. Biped biological organisms face similar difficulties, but have nevertheless solved this problem. Experimental data reveal that m...

  12. Biological and radiochemical quality control of indigenous 99mTc-radiopharmaceutical kits

    International Nuclear Information System (INIS)

    Biological and radiochemical quality control of indigenous (Pinscan) diagnostic cold kits of Methylene Diphosphonate (MDP), Tin-colloid and Diethylene Triamine Pentaacetic Acid (DTPA) was performed in parallel with imported Amersham's kits (Amerscan). The results of radiochemical purity, sterility, apyrogenicity and biodistribution of indigenous (Pinscan) kits were good and quantitatively and qualitatively comparable to those obtained with Amersham's (Amerscan) imported kits. (author) 21 refs.; 8 tabs

  13. The Use and Exchange of Biological Control Agents for Food and Agriculture

    Institute of Scientific and Technical Information of China (English)

    J.C.van; Lenteren; M.J.W.Cock; J.Brodeur; B.Barratt; F.Bigler; K.Bolckmans; F.Haas; P.G.Mason; J.R.P.Parra

    2010-01-01

    The report sets out to summarize the past and current situation regarding the practice of biologicalcontrol inrelationtothe use and exchange of genetic resources relevant for BCAs.It considers the twomain categories of biological control:classical and augmentative.Allowing access to BCAs for use inanother country imposes no risk of liability to the source country.Local scientific knowledge abouthabitats,fauna andflora,can be helpful

  14. Impact of Two Ant Species on Egg Parasitoids Released as Part of a Biological Control Program

    OpenAIRE

    Kergunteuil, Alan; Basso, César; Pintureau, Bernard

    2013-01-01

    Biological control using Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae), an egg parasitoid wasp, was tested in Uruguay to reduce populations of lepidopteran pests on soybeans. It was observed that the commercial parasitoid dispensers, which were made of cardboard, were vulnerable to small predators that succeeded in entering and emptying the containers of all the eggs parasitized by T. pretiosum. Observations in a soybean crop showed that the only small, common predators presen...

  15. Recommendations on methods for the detection and control of biological pollution in marine coastal waters

    OpenAIRE

    Olenin, Sergej; Elliott, Michael; Bysveen, Ingrid; Culverhouse, Phil F.; Daunys, Darius; Dubelaar, George B.J.; Gollasch, Stephan; Goulletquer, Philippe; Jelmert, Anders; Kantor, Yuri; Mézeth, Kjersti Bringsvor; Minchin, Dan; Occhipinti-ambrogi, Anna; OLENINA Irina; Vandekerkhove, Jochen

    2011-01-01

    Adverse effects of invasive alien species (IAS), or biological pollution, is an increasing problem in marine coastal waters, which remains high on the environmental management agenda. All maritime countries need to assess the size of this problem and consider effective mechanisms to prevent introductions, and if necessary and where possible to monitor, contain, control or eradicate the introduced impacting organisms. Despite this, and in contrast to more enclosed water bodies, the openness of...

  16. High Blood Pressure in Panama: Prevalence, Sociodemographic and Biologic Profile, Treatment, and Control (STROBE)

    OpenAIRE

    Mc Donald Posso, Anselmo J.; Motta Borrel, Jorge A.; Fontes, Flavia; Cruz Gonzalez, Clara E.; Pachón Burgos, Alvaro A.; Cumbrera Ortega, Alberto

    2014-01-01

    Abstract The objective of this study is to estimate the prevalence, treatment, and control of high blood pressure, hypertension (HBP) in Panama and assess its associations with sociodemographic and biologic factors. A cross-sectional, descriptive study was conducted in Panama by administering a survey on cardiovascular risk factors to 3590 adults and measuring their blood pressure 3 times. A single-stage, probabilistic, and randomized sampling strategy with a multivariate stratification was u...

  17. Mechanisms of biological control of Fusarium root and stem rot of greenhouse cucumber by Gliocladium catenulatum

    OpenAIRE

    Chatterton, Syama Gauri Dasi

    2010-01-01

    Gliocladium catenulatum strain J1446 (formulated as Prestop WP, Verdera Oy) is a biological control agent of Fusarium root and stem rot caused by Fusarium oxysporum f. sp. radicis-cucumerinum on greenhouse cucumber plants. The mechanisms involved in biocontrol efficacy are currently unknown. Following transformation of G. catenulatum with the ß-glucuronidase (uidA) gene, blue-stained mycelia could be seen growing on the surface and within epidermal and cortical cells of roots, stems and shoot...

  18. Interaction of Ulocladium atrum, a Potential Biological Control Agent, with Botrytis cinerea and Grapevine Plantlets

    OpenAIRE

    Sébastien Ronseaux; Essaid Ait Barka; Christophe Clément

    2013-01-01

    The effectiveness of biological control agent, Ulocladium atrum (isolates U13 and U16) in protecting Vitis vinifera L. cv. Chardonnay against gray mold disease caused by Botrytis cinerea, and simulation of the foliar defense responses was investigated. A degraded mycelium structure during cultural assay on potato dextrose agar revealed that U. atrum isolates U13 and U16 were both antagonistic to B. cinerea, mainly when isolates were inoculated two days before Botrytis. Under in vitro conditio...

  19. Climate warming increases biological control agent impact on a non-target species

    OpenAIRE

    Lu, Xinmin; Siemann, Evan; He, Minyan; Wei, Hui; Shao, Xu; Ding, Jianqing

    2014-01-01

    Climate change may shift interactions of invasive plants, herbivorous insects and native plants, potentially affecting biological control efficacy and non-target effects on native species. Here, we show how climate warming affects impacts of a multivoltine introduced biocontrol beetle on the non-target native plant Alternanthera sessilis in China. In field surveys across a latitudinal gradient covering their full distributions, we found beetle damage on A. sessilis increased with rising tempe...

  20. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    OpenAIRE

    Boer; Kuijper, B.; Heimpel, G.E.; Beukeboom, L. W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding depression because homozygosity at one or multiple sex loci leads to the production of diploid males that are typically unviable or sterile. We observed that diploid males occur at a relatively high r...

  1. Biology and host preference of the planthopper Taosa longula (Hemiptera: Dictyopharidae) a candidate for biological control of water hyacinth

    Science.gov (United States)

    Taosa longula Remes Lenicov (Hemiptera: Dictyopharidae) is a planthopper from the South American tropics that feeds on water hyacinth, Eichhornia crassipes (Mart.) Solms-Laubach (Pontederiaceae). The biology of T. longula was studied in the laboratory and field to evaluate it as a potential biologic...

  2. Herbivore-induced plant volatiles to enhance biological control in agriculture.

    Science.gov (United States)

    Peñaflor, M F G V; Bento, J M S

    2013-08-01

    Plants under herbivore attack synthetize defensive organic compounds that directly or indirectly affect herbivore performance and mediate other interactions with the community. The so-called herbivore-induced plant volatiles (HIPVs) consist of odors released by attacked plants that serve as important cues for parasitoids and predators to locate their host/prey. The understanding that has been gained on the ecological role and mechanisms of HIPV emission opens up paths for developing novel strategies integrated with biological control programs with the aim of enhancing the efficacy of natural enemies in suppressing pest populations in crops. Tactics using synthetic HIPVs or chemically/genetically manipulating plant defenses have been suggested in order to recruit natural enemies to plantations or help guiding them to their host more quickly, working as a "synergistic" agent of biological control. This review discusses strategies using HIPVs to enhance biological control that have been proposed in the literature and were categorized here as: (a) exogenous application of elicitors on plants, (b) use of plant varieties that emit attractive HIPVs to natural enemies, (c) release of synthetic HIPVs, and (d) genetic manipulation targeting genes that optimize HIPV emission. We discuss the feasibility, benefits, and downsides of each strategy by considering not only field studies but also comprehensive laboratory assays that present an applied approach for HIPVs or show the potential of employing them in the field.

  3. Parasites, politics and public science: the promotion of biological control in Western Australia, 1900-1910.

    Science.gov (United States)

    Deveson, Edward

    2016-06-01

    Biological control of arthropods emerged as a scientific enterprise in the late nineteenth century and the orchard industry of California was an early centre of expertise. In 1900, as the Australian colonies prepared for federation, each had a government entomologist attached to its agriculture department. The hiring of George Compere from California by the Western Australian Department of Agriculture began a controversial chapter in the early history of biological control that was linked to a late, local popularization of acclimatization. Compere became known as the 'travelling entomologist' and for a decade brought 'parasites' of pest insects from overseas and released them in Perth. His antagonistic disciplinary rhetoric and inflated claims for the 'parasite theory' created conflict with his counterparts in the eastern states. The resulting inter-state entomological controversy was played out in the press, revealing the political use of science for institutional and even state identity. It is a story of transnational exchanges, chance discoveries and popular public science: popular because of the promise of a simple, natural solution to agricultural insect pests and because of the public nature of the disputes it generated between the experts. This microcosm contributes to the global historiography of acclimatization, biological control, scientific exposition and the professionalization of agricultural science.

  4. Parasites, politics and public science: the promotion of biological control in Western Australia, 1900-1910.

    Science.gov (United States)

    Deveson, Edward

    2016-06-01

    Biological control of arthropods emerged as a scientific enterprise in the late nineteenth century and the orchard industry of California was an early centre of expertise. In 1900, as the Australian colonies prepared for federation, each had a government entomologist attached to its agriculture department. The hiring of George Compere from California by the Western Australian Department of Agriculture began a controversial chapter in the early history of biological control that was linked to a late, local popularization of acclimatization. Compere became known as the 'travelling entomologist' and for a decade brought 'parasites' of pest insects from overseas and released them in Perth. His antagonistic disciplinary rhetoric and inflated claims for the 'parasite theory' created conflict with his counterparts in the eastern states. The resulting inter-state entomological controversy was played out in the press, revealing the political use of science for institutional and even state identity. It is a story of transnational exchanges, chance discoveries and popular public science: popular because of the promise of a simple, natural solution to agricultural insect pests and because of the public nature of the disputes it generated between the experts. This microcosm contributes to the global historiography of acclimatization, biological control, scientific exposition and the professionalization of agricultural science. PMID:27264494

  5. Possibility of biological control of primocane fruiting raspberry disease caused by Fusarium sambucinum.

    Science.gov (United States)

    Shternshis, Margarita V; Belyaev, Anatoly A; Matchenko, Nina S; Shpatova, Tatyana V; Lelyak, Anastasya A

    2015-10-01

    Biological control agents are a promising alternative to chemical pesticides for plant disease suppression. The main advantage of the natural biocontrol agents, such as antagonistic bacteria compared with chemicals, includes environmental pollution prevention and a decrease of chemical residues in fruits. This study is aimed to evaluate the impact of three Bacillus strains on disease of primocane fruiting raspberry canes caused by Fusarium sambucinum under controlled infection load and uncontrolled environmental factors. Bacillus subtilis, Bacillus licheniformis, and Bacillus amyloliquefaciens were used for biocontrol of plant disease in 2013 and 2014 which differed by environmental conditions. The test suspensions were 10(5) CFU/ml for each bacterial strain. To estimate the effect of biological agents on Fusarium disease, canes were cut at the end of vegetation, and the area of outer and internal lesions was measured. In addition to antagonistic effect, the strains revealed the ability to induce plant resistance comparable with chitosan-based formulation. Under variable ways of cane treatment by bacterial strains, the more effective were B. subtilis and B. licheniformis demonstrating dual biocontrol effect. However, environmental factors were shown to impact the strain biocontrol ability; changes in air temperature and humidity led to the enhanced activity of B. amyloliquefaciens. For the first time, the possibility of replacing chemicals with environmentally benign biological agents for ecologically safe control of the raspberry primocane fruiting disease was shown.

  6. Biological Control of Yellow Nutsedge with the Indigenous Rust Fungus Puccinia canaliculata.

    Science.gov (United States)

    Phatak, S C; Sumner, D R; Wells, H D; Bell, D K; Glaze, N C

    1983-03-25

    Yellow nutsedge (Cyperus esculentus L.) is a serious weed problem in the United States and other countries. An indigenous rust fungus [Puccinia canaliculata (Schw.) Lagerh.], pathogenic on yellow nutsedge, was released in early spring as a potential biological control agent. The fungus inhibited nutsedge flowering and new tuber formation. The fungus also dehydrated and killed nutsedge plants. The successful control of yellow nutsedge by a rust epiphytotic under experimental conditions demonstrates the potential use of the rust in an integrated weed management system. PMID:17735196

  7. Biological control of Tetranychus urticae by Phytoseiulus macropilis and Macrolophus pygmaeus in tomato greenhouses.

    Science.gov (United States)

    Gigon, Vincent; Camps, Cédric; Le Corff, Josiane

    2016-01-01

    Biological control against phytophagous arthropods has been widely used under greenhouse conditions. Its success is dependent on a number of factors related to the abiotic conditions and to the interactions between pests and biological control agents. In particular, when multiple predator species are introduced to suppress one pest, competitive interactions might occur, including intraguild predation (IGP). In tomato crops, the spider mite Tetranychus urticae Koch is a very problematic phytophagous mite and its control is not yet satisfactory. In 2012 and 2013, the ability of a potential new predatory mite Phytoseiulus macropilis (Banks) was assessed, alone and in the presence of Macrolophus pygmaeus Rambur. Macrolophus pygmaeus is a polyphagous mirid supposed to predate on P. macropilis. Both years, under greenhouse conditions, the effectiveness of the two predators was compared between the following treatments: T. urticae, T. urticae + P. macropilis, T. urticae + M. pygmaeus, and T. urticae + P. macropilis + M. pygmaeus. The number of arthropods per tomato plant over time indicated that P. macropilis well-controlled the population of T. urticae, whereas M. pygmaeus had a very limited impact. Furthermore, there was no evidence of IGP between the two predators but in the presence of M. pygmaeus, P. macropilis tended to have a more clumped spatial distribution. Further studies should clarify the number and location of inoculation points to optimize the control of T. urticae by P. macropilis. PMID:26481345

  8. Biological control of white mold by Trichoderma harzianum in common bean under field conditions

    Directory of Open Access Journals (Sweden)

    Daniel Diego Costa Carvalho

    2015-12-01

    Full Text Available Abstract: The objective of this work was to evaluate Trichoderma harzianum isolates for biological control of white mold in common bean (Phaseolus vulgaris. Five isolates were evaluated for biocontrol of white mold in 'Perola' common bean under field conditions, in the 2009 and 2010 crop seasons. A commercial isolate (1306 and a control treatment were included. Foliar applications at 2x109 conidia mL-1 were performed at 42 and 52 days after sowing (DAS, in 2009, and at 52 DAS in 2010. The CEN287, CEN316, and 1306 isolates decreased the number of Sclerotinia sclerotiorum apothecia per square meter in comparison to the control, in both crop seasons. CEN287, CEN316, and 1306 decreased white mold severity during the experimental period, when compared to the control.

  9. Primary Study on Biological Control Potential of Trichoderma harzianum TL-1

    Institute of Scientific and Technical Information of China (English)

    Su; Zhenyu; Xiao; Man; Gao; Xinzheng; Tang; Libo; Li; Li

    2014-01-01

    Trichoderma harzianum is a widely used biocontrol fungus. The growth promoting effect of strain Trichoderma harzianum TL-1 on tomato and pepper and its biological control effects against tomato seedling damping-off and pepper blight were investigated through pot experiments. The results showed that the stain TL-1 had significant promotion effect on growth of pepper and tomato in sterilized and natural soils. With the application dose of 3. 0 and 0. 5g/ pot,their dry weight were increased up to 46% and 150% compared with control,respectively. In addition,TL-1 had good control effects against tomato seedling damping-off and pepper blight. Compared with fungicide treatment,TL-1 treatment could control diseases for long term,without repeat occurrence of diseases.

  10. High-latitude controls of thermocline nutrients and low latitude biological productivity.

    Science.gov (United States)

    Sarmiento, J L; Gruber, N; Brzezinski, M A; Dunne, J P

    2004-01-01

    The ocean's biological pump strips nutrients out of the surface waters and exports them into the thermocline and deep waters. If there were no return path of nutrients from deep waters, the biological pump would eventually deplete the surface waters and thermocline of nutrients; surface biological productivity would plummet. Here we make use of the combined distributions of silicic acid and nitrate to trace the main nutrient return path from deep waters by upwelling in the Southern Ocean and subsequent entrainment into subantarctic mode water. We show that the subantarctic mode water, which spreads throughout the entire Southern Hemisphere and North Atlantic Ocean, is the main source of nutrients for the thermocline. We also find that an additional return path exists in the northwest corner of the Pacific Ocean, where enhanced vertical mixing, perhaps driven by tides, brings abyssal nutrients to the surface and supplies them to the thermocline of the North Pacific. Our analysis has important implications for our understanding of large-scale controls on the nature and magnitude of low-latitude biological productivity and its sensitivity to climate change.

  11. Genetic Variation and Biological Control of Fusarium graminearum Isolated from Wheat in Assiut-Egypt.

    Science.gov (United States)

    Mahmoud, Amer F

    2016-04-01

    Fusarium graminearum Schwabe causes Fusarium head blight (FHB), a devastating disease that leads to extensive yield and quality loss of wheat and other cereal crops. Twelve isolates of F. graminearum were collected from naturally infected spikes of wheat from Assiut Egypt. These isolates were compared using SRAP. The results indicated distinct genetic groups exist within F. graminearum, and demonstrated that these groups have different biological properties, especially with respect to their pathogenicity on wheat. There were biologically significant differences between the groups; with group (B) isolates being more aggressive towards wheat than groups (A) and (C). Furthermore, Trichoderma harzianum (Rifai) and Bacillus subtilis (Ehrenberg) which isolated from wheat kernels were screened for antagonistic activity against F. graminearum. They significantly reduced the growth of F. graminearum colonies in culture. In order to gain insight into biological control effect in situ, highly antagonistic isolates of T. harzianum and B. subtilis were selected, based on their in vitro effectiveness, for greenhouse test. It was revealed that T. harzianum and B. subtilis significantly reduced FHB severity. The obtained results indicated that T. harzianum and B. subtilis are very effective biocontrol agents that offer potential benefit in FHB and should be harnessed for further biocontrol applications. The accurate analysis of genetic variation and studies of population structures have significant implications for understanding the genetic traits and disease control programs in wheat. This is the first known report of the distribution and genetic variation of F. graminearum on wheat spikes in Assiut Egypt. PMID:27147934

  12. State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies

    Science.gov (United States)

    Cerna, Cesario Z.; Elam, David P.; Echchgadda, Ibtissam; Sloan, Mark A.; Wilmink, Gerald J.

    2014-03-01

    Terahertz (THz) imaging and sensing technologies are increasingly being used at international airports for security screening purposes and at major medical centers for cancer and burn diagnosis. The emergence of new THz applications has directly resulted in an increased interest regarding the biological effects associated with this frequency range. Knowledge of THz biological effects is also desired for the safe use of THz systems, identification of health hazards, and development of empirically-based safety standards. In this study, we developed a state-of-the-art exposure chamber that allowed for highly controlled and reproducible studies of THz biological effects. This innovative system incorporated an industry grade cell incubator system that permitted a highly controlled exposure environment, where temperatures could be maintained at 37 °C +/- 0.1 °C, carbon dioxide (CO2) levels at 5% +/- 0.1%, and relative humidity (RH) levels at 95% +/- 1%. To maximize the THz power transmitted to the cell culture region inside the humid incubator, a secondary custom micro-chamber was fabricated and incorporated into the system. This micro-chamber shields the THz beam from the incubator environment and could be nitrogen-purged to eliminate water absorption effects. Additionally, a microscope that allowed for real-time visualization of the live cells before, during, and after THz exposure was integrated into the exposure system.

  13. Viability and stability of biological control agents on cotton and snap bean seeds.

    Science.gov (United States)

    Elliott, M L; Des Jardin, E A; Batson, W E; Caceres, J; Brannen, P M; Howell, C R; Benson, D M; Conway, K E; Rothrock, C S; Schneider, R W; Ownley, B H; Canaday, C H; Keinath, A P; Huber, D M; Sumner, D R; Motsenbocker, C E; Thaxton, P M; Cubeta, M A; Adams, P D; Backman, P A; Fajardo, J; Newman, M A; Pereira, R M

    2001-08-01

    Cotton and snap bean were selected for a multi-year, multi-state regional (south-eastern USA) research project to evaluate the efficacy of both commercial and experimental bacterial and fungal biological control agents for the management of damping-off diseases. The goal for this portion of the project was to determine the viability and stability of biological agents after application to seed. The biological seed treatments used included: (1) Bacillaceae bacteria, (2) non-Bacillaceae bacteria, (3) the fungus Trichoderma and (4) the fungus Beauveria bassiana. Seed assays were conducted to evaluate the following application factors: short-term (seed treatment; quality (i.e. isolate purity); compatibility with chemical pesticides and other biocontrol agents; application uniformity between years and plant species. For the bacterial treatments, the Bacillaceae genera (Bacillus and Paenibacillus) maintained the greatest population of bacteria per seed, the best viability over time and the best application uniformity across years and seed type. The non-Bacillaceae genera Burkholderia and Pseudomonas had the least viability and uniformity. Although Beauveria bassiana was only evaluated one year, the seed fungal populations were high and uniform. The seed fungal populations and uniformity for the Trichoderma isolates were more variable, except for the commercial product T-22. However, this product was contaminated with a Streptomyces isolate in both the years that it was evaluated. The study demonstrated that Bacillaceae can be mixed with Trichoderma isolates or with numerous pesticides to provide an integrated pest control/growth enhancement package. PMID:11517723

  14. Interaction of Ulocladium atrum, a Potential Biological Control Agent, with Botrytis cinerea and Grapevine Plantlets

    Directory of Open Access Journals (Sweden)

    Sébastien Ronseaux

    2013-09-01

    Full Text Available The effectiveness of biological control agent, Ulocladium atrum (isolates U13 and U16 in protecting Vitis vinifera L. cv. Chardonnay against gray mold disease caused by Botrytis cinerea, and simulation of the foliar defense responses was investigated. A degraded mycelium structure during cultural assay on potato dextrose agar revealed that U. atrum isolates U13 and U16 were both antagonistic to B. cinerea, mainly when isolates were inoculated two days before Botrytis. Under in vitro conditions, foliar application of U. atrum protected grapevine leaves against gray mold disease. An increase in chitinase activity was induced by the presence of U. atrum isolates indicating that the biological control agents triggered plant defense mechanisms. Moreover, U13 has the potential to colonize the grapevine plantlets and to improve their growth. The ability of U. atrum isolates to exhibit an antagonistic effect against B. cinerea in addition to their aptitude to induce plant resistance and to promote grapevine growth may explain a part of their biological activity. Hence, this study suggests that U. atrum provides a suitable biocontrol agent against gray mold in grapevines.

  15. Phenotypic charactheristics of fluorescent pseudomonss, biological control agent of lincat disease of temanggung tobacco

    Directory of Open Access Journals (Sweden)

    NINING NURUL AZIZAH

    2007-04-01

    Full Text Available Fluorescent pseudomonass isolated from local plants-rishosphere in temanggung controlled lincat disease of tobacco. This report describe phenotypic charactheristics of the bacteria in order to be used as a base for the development of the bacteria as a biological control agent of lincat disease. Phenotypic charactheristics of six isolates of fluorescent Pseudomonass which controlled lincat disease in the field were determined in the laboratory of Plant Bacteriology, Faculty of Agriculture, Gadjah Mada University. Plant pathogenicity tests were conducted by hypersensitive reaction into tobacco leaf and inoculation to tobacco plants. Antagonism test between fluorescent Pseudomonass and other candidate of biological control agents were also conducted. The results indicated that the bacteria were rod shape, Gram negative, positive reaction in catalase and oxidase tests. Nitrate reduce to nitrite, arginine was hydrolysed, fluorescent pigment were produced on King’s B medium, levan formation positive and all bacteria denitrifiy. The bacteria used urea, tween 80 and amylum were not hydrolised, poly--hydroxybutyrate was not accumulated in the cells. Negative reactions were observed for lysine decarboxylation, indol production, VP/MR reaction, and gelatn liquefation. Some compounds could be used as solely carbon sources. All isolates grew on the medium containing 2% NaCl. The best pH for growth was 6-7 and all isolates grew at 20-41C. Negative result were obtained for hypersensitive reaction and pathogenicity tests.

  16. The small hive beetle Aethina tumida: A review of its biology and control measures

    Directory of Open Access Journals (Sweden)

    Andrew G. S. CUTHBERTSON et al

    2013-10-01

    Full Text Available The small hive beetle Aethina tumida is an endemic parasitic pest and scavenger of colonies of social bees indigenous to sub-Saharan Africa. In this region this species rarely inflicts severe damage on strong colonies since the bees have develo­­ped strategies to combat them. However, A. tumida has since ‘escaped’ from its native home and has recently invaded areas such as North America and Australia where its economic impact on the apiculture industry has been significant. Small hive beetle, should it become established within Europe, represents a real and live threat to the UK bee keeping industry. Here we review the biology and current pest status of A. tumida and up to-date research in terms of both chemical and biological control used against this honey bee pest [Current Zoology 59 (5: 644–653, 2013].

  17. Biological insect control using Metarhizium anisopliae: morphological, molecular, and ecological aspects

    Directory of Open Access Journals (Sweden)

    Patricia Vieira Tiago

    2014-04-01

    Full Text Available Microbial control of insects is based on the rational use of pathogens to maintain environmentally balanced pest population levels, and Metarhizium anisopliae has been the most studied and most utilized fungal species for that purpose. The natural genetic variability of entomopathogenic fungi is considered one of the principal advantages of microbial insect control. The inter- and intraspecific variability and the genetic diversity and population structures of Metarhizium and other entomopathogenic fungi have been examined using ITS-RFLP, ISSR, and ISSP molecular markers. The persistence of M. anisopliae in the soil and its possible effects on the structures of resident microbial communities must be considered when selecting isolates for biological insect control.

  18. Biologically Based Methods for Control of Fumonisin-Producing Fusarium Species and Reduction of the Fumonisins.

    Science.gov (United States)

    Alberts, Johanna F; van Zyl, Willem H; Gelderblom, Wentzel C A

    2016-01-01

    Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof, or clay minerals pre- and post-harvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Post-harvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although, the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, post-harvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP) production, and storage management, together with

  19. Biologically Based Methods for Control of Fumonisin-producing Fusarium species and Reduction of the Fumonisins

    Directory of Open Access Journals (Sweden)

    Johanna Francina Alberts

    2016-04-01

    Full Text Available Infection by the fumonisin-producing Fusarium spp. and subsequent fumonisin contamination of maize adversely affect international trade and economy with deleterious effects on human and animal health. In developed countries high standards of the major food suppliers and retailers are upheld and regulatory controls deter the importation and local marketing of fumonisin-contaminated food products. In developing countries regulatory measures are either lacking or poorly enforced, due to food insecurity, resulting in an increased mycotoxin exposure. The lack and poor accessibility of effective and environmentally safe control methods have led to an increased interest in practical and biological alternatives to reduce fumonisin intake. These include the application of natural resources, including plants, microbial cultures, genetic material thereof or clay minerals pre- and postharvest. Pre-harvest approaches include breeding for resistant maize cultivars, introduction of biocontrol microorganisms, application of phenolic plant extracts, and expression of antifungal proteins and fumonisin degrading enzymes in transgenic maize cultivars. Postharvest approaches include the removal of fumonisins by natural clay adsorbents and enzymatic degradation of fumonisins through decarboxylation and deamination by recombinant carboxylesterase and aminotransferase enzymes. Although the knowledge base on biological control methods has expanded, only a limited number of authorized decontamination products and methods are commercially available. As many studies detailed the use of natural compounds in vitro, concepts in reducing fumonisin contamination should be developed further for application in planta and in the field pre-harvest, postharvest, and during storage and food-processing. In developed countries an integrated approach, involving good agricultural management practices, hazard analysis and critical control point (HACCP production and storage management

  20. Use of ryegrass strips to enhance biological control of aphids by ladybirds in wheat fields

    Institute of Scientific and Technical Information of China (English)

    Zhao-Ke Dong; Feng-Juan Gao; Run-Zhi Zhang

    2012-01-01

    Non-crop habitats may play a vital role in conservation biological control.This study tested the effect of ryegrass (Lolium muitiflorum L.) strips on aphid and ladybird populations in adjacent winter wheat fields.The field experiment was conducted in three ryegrass-margin wheat plots and three control plots in 2010 in North China.In spring,the same aphid species,Sitobion miscanthi (Takahashi),was found in both the ryegrass strips and wheat plots.The population density of ladybirds in the ryegrass strips (3.5±0.9/m2) was significantly higher than in the wheat plots (1.5±0.5/m2).We cut the ryegrass,forcing the ladybirds to migrate to the wheat fields.Three and eight days after cutting the ryegrass,the aphid numbers in the ryegrass-margin wheat plots decreased significantly:they were 19.9% and 53.6%,respectively,lower than in control plots.In the early period of ladybird population development,the percentage of larvae was greater in the ryegrass-margin wheat plots than in controls,and the peak number of pupae in the ryegrass-margin wheat plots occurred 5 days earlier than in the control plots.The results suggest that ryegrass strips may promote the development of ladybird populations.Cutting ryegrass can manipulate ladybirds to enhance biological aphid control in wheat fields.The efficiency of this management approach is discussed.

  1. Biological and chemical treatment of Cedrela fissilis seeds for controlling Rhizoctonia sp.

    Directory of Open Access Journals (Sweden)

    Marília Lazarotto

    2013-03-01

    Full Text Available This research evaluated the effect of a fungicide and a biological product, singly and combined, for the control of pathogens, especially Rhizoctonia sp., in seeds of Cedrela fissilis. Before the seeds treatment, the inoculation of Rhizoctonia sp., isolated from C. fissilis seeds in blotter-test and considered pathogenic for the specie, was done on half of the seeds used. After, the seeds were subjected to treatments with powder organic product based on Trichoderma spp. (singly, powder fungicide Captan (also singly, combination of two products in a maximum dose considered (100% and combination of half dose of both products, besides the control. After the seeds treatments the following tests were done: germination, emergence in vermiculite, with evaluations of seedlings and sanitary by blotter-test. No treatment could eradicate Rhizoctonia sp. inoculated seed, but the treatment with 100% of the dose of both products reduced its incidence. The combination of chemical and biological products can be a viable alternative for the treatment of C. fissililis seeds, especially in the control of Rhizoctonia sp.

  2. Assessment of Trichogramma species (Hymenoptera: Trichogrammatidae for biological control in cassava (Manihot esculenta Crantz

    Directory of Open Access Journals (Sweden)

    Marcus Alvarenga Soares

    2014-08-01

    Full Text Available Cassava is the sixth most important crop in the world, and it is attacked by many pests, such as Erinnyis ello (L. (Lepidoptera: Sphingidae. This lepidopteran pest has natural enemies that can efficiently control its population, such as Trichogramma spp. (Hymenoptera: Trichogrammatidae. The objective of this research was to assess the flight capacity, parasitism and emergence of Trichogramma pretiosum, T. marandobai and T. demoraesi and to select the most efficient species among them for biological control programs. The flight capacity of these species was assessed in test units consisting of a plastic PVC cylinder with a rigid, transparent plastic circle on the upper portion of the cylinder and an extruded polystyrene disk to close the bottom of the cylinder. A tube was placed in each test unit containing a card with 300 Anagasta kuehniella (Zeller (Lepidoptera: Pyralidae eggs that had been parasitised by Trichogramma. These cards were later assessed to determine the parasitism rate and adult emergence of these natural enemies. Trichogramma pretiosum presented the highest flight capacity (68 ± 5%, parasitism (74 ± 2% and percentage of adults emerged (91 ± 3% in the laboratory, making this species suitable for mass rearing and release in biological control programs.

  3. Precision control of recombinant gene transcription for CHO cell synthetic biology.

    Science.gov (United States)

    Brown, Adam J; James, David C

    2016-01-01

    The next generation of mammalian cell factories for biopharmaceutical production will be genetically engineered to possess both generic and product-specific manufacturing capabilities that may not exist naturally. Introduction of entirely new combinations of synthetic functions (e.g. novel metabolic or stress-response pathways), and retro-engineering of existing functional cell modules will drive disruptive change in cellular manufacturing performance. However, before we can apply the core concepts underpinning synthetic biology (design, build, test) to CHO cell engineering we must first develop practical and robust enabling technologies. Fundamentally, we will require the ability to precisely control the relative stoichiometry of numerous functional components we simultaneously introduce into the host cell factory. In this review we discuss how this can be achieved by design of engineered promoters that enable concerted control of recombinant gene transcription. We describe the specific mechanisms of transcriptional regulation that affect promoter function during bioproduction processes, and detail the highly-specific promoter design criteria that are required in the context of CHO cell engineering. The relative applicability of diverse promoter development strategies are discussed, including re-engineering of natural sequences, design of synthetic transcription factor-based systems, and construction of synthetic promoters. This review highlights the potential of promoter engineering to achieve precision transcriptional control for CHO cell synthetic biology. PMID:26721629

  4. Theoretical study of the molecular bases that control photochemical processes with biological and nanotechnological interest

    OpenAIRE

    Saurí Peris, Vicenta

    2013-01-01

    El trabajo desarrollado en la tesis doctoral que lleva por título "Theoretical study of the molecular bases that control photochemical processes with biological and nanotechnological interest" se enmarca en las líneas de investigación del grupo QCEXVAL (Quantum Chemistry of the Excited State University of Valencia), que nació en el seno del departamento de Química Física de la Universitat de València en 1993. Se han abordado temas de interés metodológico, biológico y nanotecnológico. La prime...

  5. Early pest development and loss of biological control are associated with urban warming.

    Science.gov (United States)

    Meineke, Emily K; Dunn, Robert R; Frank, Steven D

    2014-11-01

    Climate warming is predicted to cause many changes in ectotherm communities, one of which is phenological mismatch, wherein one species' development advances relative to an associated species or community. Phenological mismatches already lead to loss of pollination services, and we predict that they also cause loss of biological control. Here, we provide evidence that a pest develops earlier due to urban warming but that phenology of its parasitoid community does not similarly advance. This mismatch is associated with greater egg production that likely leads to more pests on trees.

  6. Lepidopterans as potential agents for the biological control of the invasive plant, Miconia calvescens.

    Science.gov (United States)

    Morais, Elisangela G F; Picanço, Marcelo C; Semeão, Altair A; Barreto, Robert W; Rosado, Jander F; Martins, Julio C

    2012-01-01

    This work investigated eight species of Lepidoptera associated with Miconia calvescens DC. (Myrtales: Melastomataceae) in Brazil, including six defoliators, Salbia lotanalis Druce (Lepidoptera: Pyralidae), Druentia inscita Schaus (Mimallonidae), Antiblemma leucocyma Hampson (Noctuidae), three Limacodidae species, a fruit borer Carposina cardinata Meyrick (Carposinidae), and a damager of flowers Pleuroprucha rudimentaria Guenée (Geometridae). Based on host specificity and the damage caused to plants, S. lotanalis and D. inscita are the most promising species for biological control of M. calvescens. Furthermore, if C. cardinata and P. rudimentaria have host specificity in future tests, these caterpillars could also be considered as appropriate biocontrol agents. PMID:22938203

  7. Long-­‐Term Evaluation of Leafy Spurge Biological Control at Richmond, Utah

    OpenAIRE

    Anderson, Jacob

    2014-01-01

    Leafy spurge (LS) is an aggressive Eurasian weed that has been reduced in many areas in North America through biological control releases of flea beetles. Three flea beetle species were released in the mid-1990s at a site dominated by LS in Richmond, Utah. This study assessed the long term effects of LS biocontrol on the plant community at this site by addressing four questions: (1) Is LS abundance significantly lower in 2013 than it was in the 1990s? (2) What plant species are replacin...

  8. Ex-ante analysis of economic returns from biological control of coconut mite in Tanzania

    OpenAIRE

    Oleke, J.M.; Manyong, V.; Mignouna, D.; Isinika, A.; Mutabazi, K.; Hanna, R.(DSM/IRFU (Institut de Recherches sur les Lois Fondamentales de l’Univers), CEA Saclay (Commissariat à l’Energie Atomique et aux Energies Alternatives), Gif-sur-Yvette, France); Sabelis, M.

    2013-01-01

    The coconut mite, Aceria guerreronis Keifer, has been identified as one of the pests that pose a threat to the coconut industry in Benin. The study presents the simulation results of the economic benefits of the biological control of coconut mites in Benin using a standard economic surplus model. In the least optimistic scenario, the economy would derive an overall net gain of US$155,213.40. Considered at a discount rate of 12% for the period 2008-2027, net present value was about $207,721, w...

  9. Entomopathogenic fungi as biological controllers: New insights into their virulence and pathogenicity

    Directory of Open Access Journals (Sweden)

    Shahid Ali Ahmad

    2012-01-01

    Full Text Available Entomopathogenic fungi vary considerably in their mode of action and virulence. Successful infection depends primarily on the adherence and penetration ability of a fungus to the host integuments. A variety of extracellular enzymes is produced during the degradation of insect integument. The attempts to control insects have changed over time from chemicals to natural control methods. This is why the development of natural methods of insect control or biopesticides, is preferred. By the use of fungal entomopathogens, insect pests can be controlled. There is no doubt that insects have been used for many years, but their effective use in the field remains elusive. However, their additional role in nature has also been discovered. Comparison of entomopathogens with conventional chemical pesticides depends on their efficiency and cost. In addition to efficiency, there are advantages in using microbial control agents, such as human safety and other non-target organisms; pesticide residues are minimized in food and biodiversity increased in managed ecosystems. In the present review the pathogenicity and virulence of entomopathogenic fungi and their role as biological control agents using biotechnology will be discussed.

  10. Survey of locomotion control of legged robots inspired by biological concept

    Institute of Scientific and Technical Information of China (English)

    WU QiDi; LIU ChengJu; ZHANG JiaQi; CHEN QiJun

    2009-01-01

    Compared with wheeled mobile robots, legged robots can easily step over obstacles and walk through rugged ground. They have more flexible bodies and therefore, can deal with complex environment. Nev-ertheless, some other issues make the locomotion control of legged robots a much complicated task, such as the redundant degree of freedoms and balance keeping. From literatures, locomotion control has been solved mainly based on programming mechanism. To use this method, walking trajectories for each leg and the gaits have to be designed, and the adaptability to an unknown environment cannot be guaranteed. From another aspect, studying and simulating animals' walking mechanism for engi-neering application is an efficient way to break the bottleneck of locomotion control for legged robots. This has attracted more and more attentions. Inspired by central pattern generator (CPG), a control method has been proved to be a successful attempt within this scope. In this paper, we will review the biological mechanism, the existence evidences, and the network properties of CPG. From the en-gineering perspective, we will introduce the engineering simulation of CPG, the property analysis, and the research progress of CPG inspired control method in locomotion control of legged robots. Then, in our research, we will further discuss on existing problems, hot issues, and future research directions in this field.

  11. Decreased functional diversity and biological pest control in conventional compared to organic crop fields.

    Directory of Open Access Journals (Sweden)

    Jochen Krauss

    Full Text Available Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short

  12. Decreased functional diversity and biological pest control in conventional compared to organic crop fields.

    Science.gov (United States)

    Krauss, Jochen; Gallenberger, Iris; Steffan-Dewenter, Ingolf

    2011-01-01

    Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid

  13. Geomorphic controls on biological soil crust distribution: A conceptual model from the Mojave Desert (USA)

    Science.gov (United States)

    Williams, Amanda J.; Buck, Brenda J.; Soukup, Deborah A.; Merkler, Douglas J.

    2013-08-01

    Biological soil crusts (BSCs) are bio-sedimentary features that play critical geomorphic and ecological roles in arid environments. Extensive mapping, surface characterization, GIS overlays, and statistical analyses explored relationships among BSCs, geomorphology, and soil characteristics in a portion of the Mojave Desert (USA). These results were used to develop a conceptual model that explains the spatial distribution of BSCs. In this model, geologic and geomorphic processes control the ratio of fine sand to rocks, which constrains the development of three surface cover types and biogeomorphic feedbacks across intermontane basins. (1) Cyanobacteria crusts grow where abundant fine sand and negligible rocks form saltating sand sheets. Cyanobacteria facilitate moderate sand sheet activity that reduces growth potential of mosses and lichens. (2) Extensive tall moss-lichen pinnacled crusts are favored on early to late Holocene surfaces composed of mixed rock and fine sand. Moss-lichen crusts induce a dust capture feedback mechanism that promotes further crust propagation and forms biologically-mediated vesicular (Av) horizons. The presence of thick biogenic vesicular horizons supports the interpretation that BSCs are long-lived surface features. (3) Low to moderate density moss-lichen crusts grow on early Holocene and older geomorphic surfaces that display high rock cover and negligible surficial fine sand. Desert pavement processes and abiotic vesicular horizon formation dominate these surfaces and minimize bioturbation potential. The biogeomorphic interactions that sustain these three surface cover trajectories support unique biological communities and soil conditions, thereby sustaining ecological stability. The proposed conceptual model helps predict BSC distribution within intermontane basins to identify biologically sensitive areas, set reference conditions for ecological restoration, and potentially enhance arid landscape models, as scientists address impacts

  14. Opportunities for improving risk communication during the permitting process for entomophagous biological control agents: A review of current systems

    Science.gov (United States)

    Concerns about potentially irreversible non-target impacts from the importation and release of entomophagous biological control agents (BCAs) have resulted in increasingly stringent import requirements by National Plant Protection Organizations. Despite numerous scientific publications on the poten...

  15. Innate positive chemotaxis to pollen from crops and banker plants in predaceous biological control agents: towards new field lures?

    OpenAIRE

    Shu Li; Xiaoling Tan; Nicolas Desneux; Giovanni Benelli; Jing Zhao; Xinhai Li; Fan Zhang; Xiwu Gao; Su Wang

    2015-01-01

    Predator-prey interactions form the core of biological control of arthropod pests. Which tools can be used to monitor and collect carnivorous arthropods in natural habitats and targeted crops? Eco-friendly and effective field lures are urgently needed. In this research, we carried out olfactometer experiments assess innate positive chemotaxis to pollen of seven crop and banker plant by two important predatory biological control agents: the coccinellid Propylea japonica (Thunberg) and the anth...

  16. Biological Control Of The Egyptian Brown Rot In Potato (Solanum Tuberosum L.)

    International Nuclear Information System (INIS)

    Pseudomonas fluorescence, P. aeruginosa, Bacillus subtillus and streptomyces spp. Were used in control of Ralstonia solanacearum, the casual agent of brown rot in potato. In vitro, antagonistic activities showed that streptomyces spp. was the most antagonistic followed by P. fluorescence, Bacillus subtilus and P. aeruginosa respectively. Also, in vivo, biological control of R. solanacearum showed that Streptomyces spp. was found to reduce the percentage of brown rot infection to 5% followed by P. fluorescence, Bacillus subtilus and P. aeruginosa reducing the percentage of infection to 15 , 25 and 40%, respectively. Also, the disease severity when using Streptomyces spp. and P. fluorescence was reduced from 5 to 1 and reduced from 5 to 2 when using Bacillus subtilus and P. aeruginosa.

  17. Supplemental control of lepidopterous pests on Bt transgenic sweet corn with biologically-based spray treatments.

    Science.gov (United States)

    Farrar, Robert R; Shepard, B Merle; Shapiro, Martin; Hassell, Richard L; Schaffer, Mark L; Smith, Chad M

    2009-01-01

    Biologically-based spray treatments, including nucleopolyhedroviruses, neem, and spinosad, were evaluated as supplemental controls for the fall armyworm, Spodoptera frugiperda (J. E. Smith), and corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), on transgenic sweet corn, Zea mays (L.) (Poales: Poaceae), expressing a Cry1Ab toxin from Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) (Bt). Overall, transgenic corn supported lower densities of both pests than did nontransgenic corn. Control of the fall armyworm was improved in both whorl-stage and tassel-stage corn by the use of either a nucleopolyhedrovirus or neem, but the greatest improvement was seen with spinosad. Only spinosad consistently reduced damage to ears, which was caused by both pest species. In general, efficacy of the spray materials did not differ greatly between transgenic and nontransgenic corn.

  18. Cyclodextrin induced controlled delivery of a biological photosensitizer from a nanocarrier to DNA.

    Science.gov (United States)

    Kundu, Pronab; Ghosh, Saptarshi; Das, Sinjan; Chattopadhyay, Nitin

    2016-02-01

    In this article, we have addressed to a demanding physicochemical aspect of therapeutic and drug research. We have reported a simple yet prospective technique that can be exploited for the controlled delivery of drugs and/or bioactive small molecules to the most relevant biomolecular target DNA. Exploiting various steady state and time resolved spectroscopic techniques together with the DNA helix melting study, we have shown that a biologically significant photosensitizer, namely, phenosafranin (PSF), can be quantitatively transferred to the DNA from the micellar nanocarrier made up of sodium tetradecyl sulfate (STS) using the external stimulant β-cyclodextrin (β-CD). The complexation property of β-CD with the nanocarrier (STS) has been utilized for the controlled release of the probe from the micelle to the DNA. Non-toxicity of the stimulant and the noninvasive nature of the carrier towards the target are expected to add to the suitability of this approach from a clinical perspective. PMID:26758082

  19. Biological Control of Spreading Dayflower (Commelina diffusa with the Fungal Pathogen Phoma commelinicola

    Directory of Open Access Journals (Sweden)

    Clyde D. Boyette

    2015-10-01

    Full Text Available Greenhouse and field experiments showed that conidia of the fungal pathogen, Phoma commelinicola, exhibited bioherbicidal activity against spreading dayflower (Commelina diffusa seedlings when applied at concentrations of 106 to 109 conidia·mL−1. Greenhouse tests determined an optimal temperature for conidial germination of 25 °C–30 °C, and that sporulation occurred on several solid growth media. A dew period of ≥ 12 h was required to achieve 60% control of cotyledonary-first leaf growth stage seedlings when applications of 108 conidia·mL−1 were applied. Maximal control (80% required longer dew periods (21 h and 90% plant dry weight reduction occurred at this dew period duration. More efficacious control occurred on younger plants (cotyledonary-first leaf growth stage than older, larger plants. Mortality and dry weight reduction values in field experiments were ~70% and >80%, respectively, when cotyledonary-third leaf growth stage seedlings were sprayed with 108 or 109 conidia·mL−1. These results indicate that this fungus has potential as a biological control agent for controlling this problematic weed that is tolerant to the herbicide glyphosate.

  20. Laboratory Study on Biological Control of Ticks (Acari: Ixodidae by Entomopathogenic Indigenous Fungi (Beauveria bassiana

    Directory of Open Access Journals (Sweden)

    M Abdigoudarzi

    2009-12-01

    Full Text Available Background: Chemical control method using different acaricides as spray, dipping solution or pour-on is routinely used for controlling ticks. Biological control agents are favorable due to their safety for animals and environment. Entomopathogenic fungi such as Beauveria bassiana are well known for controlling ticks. In this study, two Iranian indigenous strains of B. bassiana (B. bassiana 5197 and B. bassiana Evin were selected and grown on specific me­dia. The pathogenic effects of these strains were evaluated on adult stages of two Iranian Ixodidae members (H. anatolicum anatolicum Koch 1844, and H. marginatum Koch 1844 by dipping method.Methods: Two Iranian strains of Beauveria bassiana (Beauveria bassiana 5197 and Beauveria bassiana Evin were selected and were grown successfully on specific media. The pathogenic effects of these strains were evaluated on adult stages of Iranian Ixodidae members such as, Hyalomma anatolicum anatolicum and H. marginatum by dipping method (these ticks were grown up at laboratory conditions during 2002 up to 2003 and still it is continued .Results: There was no effect of strain 5197 on mortality or fecundity rates for ticks. There was acute phase sign of paralysis in test group after dipping ticks in suspension made from Evin strain of B. bassiana. In addition, the test groups were totally died after four months, but the control groups survived for six months.Conclusion: High concentration of fungal spores is needed for inducing fungal infection. Additional study using different strains and fungi on Iranian ticks is proposed. 

  1. Biological control of terrestrial silica cycling and export fluxes to watersheds.

    Science.gov (United States)

    Derry, Louis A; Kurtz, Andrew C; Ziegler, Karen; Chadwick, Oliver A

    2005-02-17

    Silicon has a crucial role in many biogeochemical processes--for example, as a nutrient for marine and terrestrial biota, in buffering soil acidification and in the regulation of atmospheric carbon dioxide. Traditionally, silica fluxes to soil solutions and stream waters are thought to be controlled by the weathering and subsequent dissolution of silicate minerals. Rates of mineral dissolution can be enhanced by biological processes. But plants also take up considerable quantities of silica from soil solution, which is recycled into the soil from falling litter in a separate soil-plant silica cycle that can be significant in comparison with weathering input and hydrologic output. Here we analyse soil water in basaltic soils across the Hawaiian islands to assess the relative contributions of weathering and biogenic silica cycling by using the distinct signatures of the two processes in germanium/silicon ratios. Our data imply that most of the silica released to Hawaiian stream water has passed through the biogenic silica pool, whereas direct mineral-water reactions account for a smaller fraction of the stream silica flux. We expect that other systems exhibiting strong Si depletion of the mineral soils and/or high Si uptake rates by biomass will also have strong biological control on silica cycling and export. PMID:15716949

  2. COMPLEMENTARY SEX DETERMINATION IN HYMENOPTERAN PARASITOIDS AND ITS IMPLICATIONS FOR BIOLOGICAL CONTROL

    Institute of Scientific and Technical Information of China (English)

    WUZhishan; KeithR.Hopper; PaulJ.Ode; RogerW.Fuester; CHENJia-hua; GeorgeE.Heimpel

    2003-01-01

    In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.

  3. Computing the uncertainty associated with the control of ecological and biological systems

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini

    2013-09-01

    Full Text Available Recently, I showed that ecological and biological networks can be controlled by coupling their dynamics to evolutionary modelling. This provides numerous solutions to the goal of guiding a system's behaviour towards the desired result. In this paper, I face another important question: how reliable is the achieved solution? In other words, which is the degree of uncertainty about getting the desired result if values of edges and nodes were a bit different from optimized ones? This is a pivotal question, because it's not assured that while managing a certain system we are able to impose to nodes and edges exactly the optimized values we would need in order to achieve the desired results. In order to face this topic, I have formulated here a 3-parts framework (network dynamics - genetic optimization - stochastic simulations and, using an illustrative example, I have been able to detect the most reliable solution to the goal of network control. The proposed framework could be used to: a counteract damages to ecological and biological networks, b safeguard rare and endangered species, c manage systems at the least possible cost, and d plan optimized bio-manipulations.

  4. Effect of non-crop vegetation types on conservation biological control of pests in olive groves

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    Daniel Paredes

    2013-07-01

    Full Text Available Conservation biological control (CBC is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two important pests: the olive psyllid (Euphyllura olivina and the olive moth (Prays oleae. Areas of herbaceous vegetation and areas of woody vegetation near olive crops, and smaller patches of woody vegetation within olive groves, decreased pest abundance in the crop. Inter-row ground covers that are known to increase the abundance of some predators and parasitoids had no effect on the pests, possibly as a result of lack of synchrony between pests and natural enemies, lack of specificity or intra-guild predation. This study identifies examples of the right types of diversity for use in conservation biological control in olive production systems.

  5. Improving the biological control of leaf-miners (Diptera: Agromyzidae) using the sterile insect technique

    International Nuclear Information System (INIS)

    The leafminer Liriomyza trifolii (Burgess) (Diptera: Agromyzidae) is a worldwide pest of ornamental and vegetable crops. The most promising nonchemical approach for controlling Liriomiza leafminers in greenhouses is regular releases of the parasitoid Diglyphus isaea (Walker) (Hymenoptera: Eulophidae). In the current study, we examine the hypothesis that the use of D. isaea for biological control of leafminers in greenhouse crops may be more practical and efficient when supplemented with additional control strategies, such as the sterile insect technique (SIT). In small cages, our SIT experiments suggest that releases of sterile L. trifolii males in three sterile-to-fertile male ratios (3:1, 5:1, and 10:1) can significantly reduce the number of the pest offspring. In large cage experiments, when both parasitoids and sterile males were released weekly, the combined methods significantly reduced mine production and the adult leafminer population size. Moreover, a synergistic interaction between these two methods was found, and a model based on our observed data predicts that because of this effect, only the use of both methods can eradicate the pest population. Our study indicates that an integrated pest management approach that combines the augmentative release of the parasitoid D. isaea together with sterile leafminer males is more efficient than the use of either method alone. In addition, our results validate previous theoretical models and demonstrate synergistic control with releases of parasitoids and sterile insects. (author)

  6. Maneuvering control and configuration adaptation of a biologically inspired morphing aircraft

    Science.gov (United States)

    Abdulrahim, Mujahid

    Natural flight as a source of inspiration for aircraft design was prominent with early aircraft but became marginalized as aircraft became larger and faster. With recent interest in small unmanned air vehicles, biological inspiration is a possible technology to enhance mission performance of aircraft that are dimensionally similar to gliding birds. Serial wing joints, loosely modeling the avian skeletal structure, are used in the current study to allow significant reconfiguration of the wing shape. The wings are reconfigured to optimize aerodynamic performance and maneuvering metrics related to specific mission tasks. Wing shapes for each mission are determined and related to the seagulls, falcons, albatrosses, and non-migratory African swallows on which the aircraft are based. Variable wing geometry changes the vehicle dynamics, affording versatility in flight behavior but also requiring appropriate compensation to maintain stability and controllability. Time-varying compensation is in the form of a baseline controller which adapts to both the variable vehicle dynamics and to the changing mission requirements. Wing shape is adapted in flight to minimize a cost function which represents energy, temporal, and spatial efficiency. An optimal control architecture unifies the control and adaptation tasks.

  7. Biological control via "ecological" damping: An approach that attenuates non-target effects.

    Science.gov (United States)

    Parshad, Rana D; Quansah, Emmanuel; Black, Kelly; Beauregard, Matthew

    2016-03-01

    In this work we develop and analyze a mathematical model of biological control to prevent or attenuate the explosive increase of an invasive species population, that functions as a top predator, in a three-species food chain. We allow for finite time blow-up in the model as a mathematical construct to mimic the explosive increase in population, enabling the species to reach "disastrous", and uncontrollable population levels, in a finite time. We next improve the mathematical model and incorporate controls that are shown to drive down the invasive population growth and, in certain cases, eliminate blow-up. Hence, the population does not reach an uncontrollable level. The controls avoid chemical treatments and/or natural enemy introduction, thus eliminating various non-target effects associated with such classical methods. We refer to these new controls as "ecological damping", as their inclusion dampens the invasive species population growth. Further, we improve prior results on the regularity and Turing instability of the three-species model that were derived in Parshad et al. (2014). Lastly, we confirm the existence of spatiotemporal chaos.

  8. Area-wide integration of lepidopteran F1 sterility and augmentative biological control

    International Nuclear Information System (INIS)

    Area-wide pest management (APM) and integrated pest management (IPM) originated from two different efforts to combine two or more control techniques into programmes in which each method could synergise the effectiveness of others and thus create a level of pest control that was greater than that of a single technique (Perkins 1982). Since then, the concept of APM has evolved to include many aspects of IPM and often is now referred to as area-wide IPM. Still, the element of total population management is central to this approach of insect pest management. In support of APM, Knipling (1998) stated that of the insect pests that were of major concern to agriculture before the newer classes of insecticides were available, most are still pests today, the major exceptions being the screw-worm fly and the boll weevil in the southeastern US cotton growing region. Knipling also noted that both of these pest species were subjected to area-wide suppression programmes. In response to the USDA IPM Initiative (USDA 1993, 1994) which seeks to achieve the national goal of having 75% of the crop acres under IPM by the year 2000, the Agricultural Research Service developed an Area-wide IPM Programme. This programme combines environmentally-sound pest control techniques with the advantages of APM and develops partnerships with other federal, state, local and private sector entities. Technologies such as the integration of lepidopteran F1 sterility and augmentative biological control may be considered for future programmes

  9. Diaporthe endophytica and D. terebinthifolii from medicinal plants for biological control of Phyllosticta citricarpa.

    Science.gov (United States)

    Santos, Paulo José Camargo Dos; Savi, Daiani Cristina; Gomes, Renata Rodrigues; Goulin, Eduardo Henrique; Da Costa Senkiv, Camila; Tanaka, Francisco André Ossamu; Almeida, Álvaro Manuel Rodrigues; Galli-Terasawa, Lygia; Kava, Vanessa; Glienke, Chirlei

    2016-01-01

    The citrus industry is severely affected by citrus black spot (CBS), a disease caused by the pathogen Phyllosticta citricarpa. This disease causes loss of production, decrease in the market price of the fruit, and reduction in its export to the European Union. Currently, CBS disease is being treated in orchards with various pesticides and fungicides every year. One alternative to CBS disease control without harming the environment is the use of microorganisms for biological control. Diaporthe endophytica and D. terebinthifolii, isolated from the medicinal plants Maytenus ilicifolia and Schinus terebinthifolius have an inhibitory effect against P. citricarpa in vitro and in detached fruits. Moreover, D. endophytica and D. terebinthifolii were transformed by Agrobacterium tumefaciens for in vivo studies. The transformants retained the ability to control of phytopathogenic fungus P. citricarpa after transformation process. Furthermore, D. endophytica and D. terebinthifolii were able to infect and colonize citrus plants, which is confirmed by reisolation of transformants from inoculated and uninoculated leaves. Light microscopic analysis showed fungus mycelium colonizing intercellular region and oil glands of citrus, suggesting that these two new species are capable of colonizing citrus plants, in addition to controlling the pathogen P. citricarpa. PMID:27242153

  10. Molecular biological approaches to the study of vectors in relation to malaria control

    Directory of Open Access Journals (Sweden)

    J. M. Crampton

    1992-01-01

    Full Text Available To a large extent, control of malaria vectors relies on the elimination of breeding sites and the application of chemical agents. There are increasing problems associated with the use of synthetic insecticides for vector control, including the evolution of resistance, the high cost of developing and registering new insecticides and an awareness of pollution from insecticide residues. These factors have stimulated interest in the application of molecular biology to the study of mosquito vectors of malaria; focussing primarily on two aspects. First, the improvement of existing control measures through the development of simplified DNA probe systems suitable for identification of vectors of malaria. The development of synthetic, non-radioactive DNA probes suitable for identification of species in the Anopheles gambiae complex is described with the aim of defining a simplified methodology wich is suitable for entomologist in the field. The second aspect to be considered is the development of completely novel strategies through the development of completely novel strategies through the genetic manipulation of insect vectors of malaria in order to alter their ability to transmit the disease. The major requirements for producing transgenic mosquitoes are outlined together with the progress wich has been made to date and discussed in relation to the prospects which this type of approach has for the future control of malaria.

  11. Bacteriocin Serratine-P as a biological tool in the control of fire blight Erwinia amylovora.

    Science.gov (United States)

    Schoofs, H; Vandebroek, K; Pierrard, A; Thonart, P; Lepoivre, P; Beaudry, T; Deckers, T

    2002-01-01

    Fire blight, caused by the bacterium Erwinia amylovora (Burill Winslow et al.), is the most important bacterial disease in European pear growing. It can cause a lot of damage in some countries on apple and on pear trees in orchards and also in the fruit tree nurseries. In Belgium, the disease is present since 1972. Control of fire blight in Belgian fruit orchards is made on a broad basis of measurements in and around the fruit trees. The use of an antibiotic is allowed for application only during the primary blossom period under strict controlled regulations. The use of antobiotics in agriculture is strongly discussed on the European level today and will probably disappear in the near future. Therefore, the research on fire blight control concentrates on the possibilities of biological control with antagonistic bacteria such as Pantoea agglomerans (Erwinia herbicola), Bacillus subtilis or Pseudomonas syringae strain A 506. The use of Serratine-P, a phage tail-like bacteriocin, produced by Serratia plymiticum, shows an interesting antibacterial activity against Erwinia amylovora. Its mode of action consists in the perforation of the cytoplasmic membrane of the target cell, inducing perturbations in cellular exchanges and a final lysis of the bacterial cell. In this paper some trials are discussed on the use of Serratine-P at different doses and on different infection types on pear trees. The results indicate interesting protection possibilities on blossom- and fruit infections. PMID:12701444

  12. Supplemental food that supports both predator and pest: a risk for biological control?

    Science.gov (United States)

    Leman, Ada; Messelink, Gerben J

    2015-04-01

    Supplemental food sources to support natural enemies in crops are increasingly being tested and used. This is particularly interesting for generalist predators that can reproduce on these food sources. However, a potential risk for pest control could occur when herbivores also benefit from supplemental food sources. In order to optimize biological control, it may be important to select food sources that support predator populations more than herbivore populations. In this study we evaluated the nutritional quality of four types of supplemental food for the generalist predatory mites Amblyseius swirskii Athias-Henriot and Amblydromalus (Typhlodromalus) limonicus (Garman and McGregor), both important thrips predators, and for the herbivore western flower thrips Frankliniella occidentalis Pergande, by assessing oviposition rates. These tests showed that application of corn pollen, cattail pollen or sterilized eggs of Ephestia kuehniella Zeller to chrysanthemum leaves resulted in three times higher oviposition rates of thrips compared to leaves without additional food. None of the tested food sources promoted predatory mites or western flower thrips exclusively. Decapsulated cysts of Artemia franciscana Kellogg were not suitable, whereas cattail pollen was very suitable for both predatory mites and western flower thrips. In addition, we found that the rate of thrips predation by A. swirskii can be reduced by 50 %, when pollen is present. Nevertheless, application of pollen or Ephestia eggs to a chrysanthemum crop still strongly enhanced the biological control of thrips with A. swirskii, both at low and high release densities of predatory mites through the strong numerical response of the predators. Despite these positive results, application in a crop should be approached with caution, as the results may strongly depend on the initial predator-prey ratio, the nutritional quality of the supplemental food source, the species of predatory mites, the distribution of the

  13. Purpureocillium lilacinum, potential agent for biological control of the leaf-cutting ant Acromyrmex lundii.

    Science.gov (United States)

    Goffré, D; Folgarait, P J

    2015-09-01

    Many leaf-cutter ant species are well known pests in Latin America, including species of the genera Acromyrmex and Atta. An environmentally friendly strategy to reduce the number of leafcutter ants and avoid indiscriminate use of chemical pesticides is biological control. In this work we evaluated the effectiveness of a strain of the entomopathogen Purpureocillium lilacinum, against worker ants from six Acromyrmex lundii field colonies, after immersions in pure suspensions at a concentration of 1×10(6)conidiaml(-1). Survival of ants treated with P. lilacinum was significantly lower than that recorded in controls, and median lethal time (LT50) was 6-7days. P. lilacinum was responsible for 85.6% (80.6-89.7) of the mortality in inoculated ants, in which we found that the percentage of other entomopathogens that naturally infected ants decreased also, suggesting a good competitive capability of the fungus. Horizontal transmission to non-inoculated ants was also evidenced, given that 58.5% (41.9-64.2) of them died because of P. lilacinum. Moreover, we tested pathogenicity for three concentrations of this strain (1.0×10(4), 10(6) and 10(8)conidiaml(-1)) and found a significantly faster mortality of ants and greater median percentage of infection at 10(8)conidiaml(-1) of P. lilacinum. CL50 value was 2.8×10(5)conidiaml(-1). We thus propose the use of P. lilacinum as a biological control agent of leafcutter ants in crops and plantations. PMID:26205173

  14. Strong biological controls on Sr/Ca ratios in aragonitic marine bivalve shells

    Science.gov (United States)

    Gillikin, David Paul; Lorrain, Anne; Navez, Jacques; Taylor, James W.; André, Luc; Keppens, Eddy; Baeyens, Willy; Dehairs, Frank

    2005-05-01

    It is well known that skeletal remains of carbonate secreting organisms can provide a wealth of information about past environments. Sr/Ca ratios have been successfully used as a temperature proxy in corals and sclerosponges. Previous work on aragonitic bivalve shells has not been conclusive but suggests a major control of growth rate on Sr/Ca ratios. As many studies have used bivalve growth rates to determine temperature, we tested if Sr/Ca ratios could predict temperature through its relationship with growth rate. Shells from the two species of clams from the same family (veneroidea) studied here, Saxidomus giganteus and Mercenaria mercenaria, show vastly different seasonal Sr/Ca profiles. A strong relationship between average annual Sr/Ca ratios and annual growth rate was found in S. giganteus shells from both Washington (R2 = 0.87) and Alaska (R2 = 0.64), USA, but not in M. mercenaria shells from North Carolina, USA. Furthermore, the Sr/Ca-growth rate relationship was also evident upon a more detailed inspection of subannual growth rates in S. giganteus (R2 = 0.73). Although there were significant positive correlations between Sr/Ca ratios and temperature in S. giganteus shells, the correlations were weak (0.09 control in either clam species, since thermodynamics predict a negative correlation between Sr/Ca ratios and temperature in aragonite. This points toward dominance of biological processes in the regulation of Sr2+. This is also reflected by the largely differing Sr/Ca partition coefficients (DSr) in these shells (DSr ≈ 0.25), when compared to inorganic, coral, and sclerosponge studies (DSr ≈ 1), all of which show a negative dependence of Sr/Ca on temperature. We suggest that caution be taken when using Sr/Ca in any biogenic aragonite as a temperature proxy when the DSr greatly deviates from one, as this indicates the dominance of biological controls on Sr/Ca ratios.

  15. Fungal biological control agents for integrated management of Culicoides spp. (Diptera: Ceratopogonidae of livestock

    Directory of Open Access Journals (Sweden)

    B. W. Narladkar

    2015-02-01

    Full Text Available Aim: Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana had wide host range against insects and hence these are being exploited as fungal bio-pesticide on a large scale. Both fungi are proved pesticides against many crop pests and farmers are well acquainted with their use on the field. Thus, research was aimed to explore the potency of these fungal spores against larval and adult Culicoides midges, a pest of livestock. Materials and Methods: In-vitro testing of both fungal biological control agents was undertaken in Petri dishes against field collected Culicoides larvae, while in plastic beakers against field collected blood-engorged female Culicoides midges. In-vivo testing was undertaken by spraying requisite concentration of fungal spores on the drainage channel against larvae and resting sites of adult Culicoides midges in the cattle shed. Lethal concentration 50 (LC50 values and regression equations were drawn by following probit analysis using SPSS statistical computerized program. Results: The results of this study revealed LC50 values of 2692 mg and 3837 mg (108 cfu/g for B. bassiana and M. anisopliae, respectively, against Culicoides spp. larvae. Death of Culicoides larvae due to B. bassiana showed greenish coloration in the middle of the body with head and tail showed intense blackish changes, while infection of M. anisopliae resulted in death of Culicoides larvae with greenish and blackish coloration of body along with total destruction, followed by desquamation of intestinal channel. The death of adult Culicoides midges were caused by both the fungi and after death growth of fungus were very well observed on the dead cadavers proving the efficacy of the fungus. Conclusion: Preliminary trials with both funguses (M. anisopliae, B. bassiana showed encouraging results against larvae and adults of Culicoides spp. Hence, it was ascertained that, these two fungal molecules can form a part of biological control and

  16. Biological control of mycotoxin-producing molds Controle biológico de fungos de armazenamento produtores de micotoxinas

    Directory of Open Access Journals (Sweden)

    Flávio Henrique Vasconcelos de Medeiros

    2012-10-01

    Full Text Available Mycotoxins are produced by the secondary metabolism of many fungi and can be found in almost 25% of the world's agricultural commodities. These compounds are toxic to humans, animals, and plants and therefore, efforts should be made to avoid mycotoxin contamination in food and feed. Besides, up to 25% of all harvested fruits and vegetables are lost due to storage molds and/or mycotoxin contamination and many methods have been applied to mitigate these issues, but most of them rely on the use of fungicides. Although chemicals are often the first defensive line against mycotoxigenic fungi, the indiscriminate use of fungicides are awakening the public perception due to their noxious effects on the environment and human/animal health. Thus, there is an increasing public pressure for a safer and eco-friendly alternative to control these organisms. In this background, biological control using microbial antagonists such as bacteria, fungi and yeasts have been shown to be a feasible substitute to reduce the use of chemical compounds. Despite of the positive findings using the biocontrol agents only a few products have been registered and are commercially available to control mycotoxin-producing fungi. This review brings about the up-to-date biological control strategies to prevent or reduce harvested commodity damages caused by storage fungi and the contamination of food and feed by mycotoxins.As micotoxinas são produzidas pelo metabolismo secundário de várias espécies de fungos e podem ser encontradas em quase 25% das commodities agrícolas. Esses compostos são tóxicos a humanos, animais e plantas e, portanto, esforços para evitar a contaminação de micotoxinas em alimentos e rações devem ser feitos. Além disso, até 25% das frutas e legumes em pós-colheita são perdidos em decorrência do ataque de fungos de armazenamento e/ou contaminações por micotoxinas. Vários métodos têm sido aplicados para mitigar os problemas de micotoxinas

  17. Risk assessment, eradication, and biological control: global efforts to limit Australian acacia invasions

    Science.gov (United States)

    Wilson, John R.U.; Gairifo, Carla; Gibson, Michelle R.; Arianoutsou, Margarita; Bakar, Baki B.; Baret, Stephane; Celesti-Grapow, Laura; DiTomaso, Joseph M.; Dufour-Dror, Jean-Marc; Kueffer, Christoph; Kull, Christian A.; Hoffman, John H.; Impson, Fiona A.C.; Loope, Lloyd L.; Marchante, Elizabete; Harchante, Helia; Moore, Joslin L.; Murphy, Daniel J.; Tassin, Jacques; Witt, Arne; Zenni, Rafael D.; Richardson, David M.

    2011-01-01

    Aim Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group. Location Global. Methods Using information from literature sources, knowledge and experience of the authors, and the responses from a questionnaire sent to experts around the world, we reviewed: (1) a generalized life cycle of Australian acacias and how to control each life stage, (2) different management approaches and (3) what is required to help limit or prevent invasions. Results Relatively few Australian acacias have been introduced in large numbers, but all species with a long and extensive history of planting have become invasive somewhere. Australian acacias, as a group, have a high risk of becoming invasive and causing significant impacts as determined by existing assessment schemes. Moreover, in most situations, long-lived seed banks mean it is very difficult to control established infestations. Control has focused almost exclusively on widespread invaders, and eradication has rarely been attempted. Classical biological control is being used in South Africa with increasing success. Main conclusions A greater emphasis on pro-active rather than reactive management is required given the difficulties managing established invasions of Australian acacias. Adverse effects of proposed new introductions can be minimized by conducting detailed risk assessments in advance, planning for on-going monitoring and management, and ensuring resources are in place for long-term mitigation. Benign alternatives (e.g. sterile hybrids) could be developed to replace existing utilized taxa. Eradication should be set as a management goal more often to reduce the invasion debt. Introducing classical biological control agents that have a successful track-record in South Africa to other regions and identifying new

  18. Application of Bathurin and borax in the biological control of Monomorium pharaonis in housing estates.

    Science.gov (United States)

    Vobrázková, E; Vanková, J; Samsinák, K

    1976-05-01

    Of two apartment houses infested with ants of the species Monomorium pharaonis, one was treated with a biological, the other with a chemical substance. In the first case we used Bathurin in combination with borax at a concentration of 1.3% for both substances. In the first week, borax was added to the bait (minced beef), within the next three weeks, the bait was mixed with Bathurin. The procedure was repeated 5 times. After this period, we achieved complete control of the ants on the infested premises.--Our results obtained with the chemical substance (the insecticide Anthrix) were less successful. This indicates that the first method, although time-consuming and requiring a perfect collaboration with all inhabitants, is safer, because it leads to the complete eradication of ants in the infested premises.

  19. Mind-body therapies and control of inflammatory biology: A descriptive review.

    Science.gov (United States)

    Bower, Julienne E; Irwin, Michael R

    2016-01-01

    The use of mind-body therapies, including Tai Chi, Qigong, yoga, and meditation, has grown steadily in recent years. These approaches have been shown to be effective in reducing symptoms and improving quality of life, and research has begun to examine the impact of these therapies on biological processes, including inflammation. A review of 26 randomized controlled trials was conducted to describe the effects of mind-body therapies (MBTs) on circulating, cellular, and genomic markers of inflammation. This qualitative evaluation showed mixed effects of MBTs on circulating inflammatory markers, including CRP and IL-6, and on measures of stimulated cytokine production. More consistent findings were seen for genomic markers, with trials showing decreased expression of inflammation-related genes and reduced signaling through the proinflammatory transcription factor NF-κB. Potential mechanisms for these effects are discussed, including alterations in neuroendocrine, neural, and psychological and behavioral processes. PMID:26116436

  20. Suppressive composts from organic wastes as agents of biological control of fusariosis in Tatartan Republic (Russia)

    Science.gov (United States)

    Gumerova, Raushaniya; Galitskaya, Polina; Beru, Franchesca; Selivanovskaya, Svetlana

    2015-04-01

    Plant diseases are one of the seriously limiting factors of agriculture efficiency around the world. Diseases caused by fungi are the major threat to plants. Crop protection in modern agriculture heavily depends on chemical fungicides. Disadvantages of chemical pesticides soon became apparent as damage to the environment and a hazard to human health. In this regard use of biopesticides becomes an attractive alternative method of plant protection. For biological control of fungal plant diseases, separate bacterial or fungal strains as well as their communities can be used. Biopreparations must consist of microbes that are typical for local climate and soil conditions and therefore are able to survive in environments for a long time. Another option of plant pests' biological control is implementation of suppressive composts made of agricultural or other organic wastes. These composts can not only prevent the development of plant diseases, but also improve the soil fertility. The objective of this work was estimation of potential of composts and strains isolated from these composts as means for biological control of fusariosis that is one of the most widespread plant soil born disease. The composts were made up of the commonly produced agricultural wastes produced in Tatarstan Republic (Russia). Fusarium oxysporum f. sp. radicis-lycopersici was used as a model phytopathogen. Ten types of organic waste (Goat manure (GM), Chicken dung (CD), Chicken dung with straw addition (CS), Rabbit dung (RD), Cow manure (CM), Rerotting pork manure (RPM), Fresh pork manure (FPM), Pork manure with sawdust and straw (PMS), the remains of plants and leaves (PL), the vegetable waste (VW) were sampled in the big farms situated in Tatarstan Republic which is one of the main agricultural regions of Russia. The initial wastes were composted for 150 days. Further, the following characteristics of the composts were assessed: pH, electro conductivity, TOC, DOC, Ntot. On petri dishes with meat

  1. Canada thistle biological control agents on two South Dakota wildlife refuges

    Science.gov (United States)

    Reed, C.C.; Larson, D.L.; Larson, J.L.

    2006-01-01

    We monitored populations of Canada thistle biocontrol agents Cassida rubiginosa, Ceutorhynchus litura, Larinus (= Hadroplantus) planus, Urophora cardui, Orellia (= Terellia) ruficauda, and Rhinocyllus conicus on Canada thistle (Cirsium arvense) at two national wildlife refuges in South Dakota from 1999 through 2003. C. litura, U. cardui, O. ruficauda, and R. conicus were present on both refuges. Agent populations were low except for C. litura, which was present in up to 90% of stems in some plots. C. litura infestation did not reduce thistle flowering, stem length, or over-winter survival. There was no change in thistle stem numbers over the study period and no difference in stem numbers in areas of high C. litura populations compared to areas of low C. litura populations. Our results suggest that insect biological control agents are inadequate for reduction of Canada thistle in southern South Dakota.

  2. ECOLOGY OF PANTOEA AGGLOMERANS 2066-7 STRAIN: A BIOLOGICAL CONTROL OF BACTERIA ONION DISEASES

    Directory of Open Access Journals (Sweden)

    Soumia Sadik

    2016-06-01

    Full Text Available The growth response of the biocontrol agent Pantoea agglomerans 2066-7 to change in water activity (aw, temperature, and pH was determined in vitro in basic medium. The minimum temperature at which 2066-7 was able to grow was 7°C, and the growth of 2066-7 did not change at varying pH levels (4–10.34. The best growth was obtained at a water activity of 0.98 in all media modified with the four solutes (glucose, glycerol, NaCl and polyethylene glycol. The solute used to reduce water activity had a great influence on bacterial growth, especially at unfavorable conditions (low temperature. This study has defined the range of environmental conditions (aw, pH, and temperature over which the bacteria may be developed for biological control of plant diseases.

  3. The possible usage of mycoviruses in biological control against tree pathogenic fungi

    Directory of Open Access Journals (Sweden)

    Ayşe Gülden Aday Kaya

    2015-01-01

    Full Text Available Mycoviruses in many organism including plant pathogenic fungi. They are mostly spread intracellularly via asexual and sexual reproduction of the fungi and cause some changes on them. Although many mycoviruses have no clear effect on their hosts, there are also many reports that they cause some phenotypic chances. Especially, they have effect on plant pathogenic fungi by increasing or decreasing their virulence. When they reduce the virulence of the host like in Chestnut canker sample, it is possible to use them in biological control. In this review, mycoviruses detected on some important fungal pathogens of forest trees both in our country and world were introduced and the studies carried out were summarized.

  4. A biologically inspired meta-control navigation system for the Psikharpax rat robot

    International Nuclear Information System (INIS)

    A biologically inspired navigation system for the mobile rat-like robot named Psikharpax is presented, allowing for self-localization and autonomous navigation in an initially unknown environment. The ability of parts of the model (e.g. the strategy selection mechanism) to reproduce rat behavioral data in various maze tasks has been validated before in simulations. But the capacity of the model to work on a real robot platform had not been tested. This paper presents our work on the implementation on the Psikharpax robot of two independent navigation strategies (a place-based planning strategy and a cue-guided taxon strategy) and a strategy selection meta-controller. We show how our robot can memorize which was the optimal strategy in each situation, by means of a reinforcement learning algorithm. Moreover, a context detector enables the controller to quickly adapt to changes in the environment—recognized as new contexts—and to restore previously acquired strategy preferences when a previously experienced context is recognized. This produces adaptivity closer to rat behavioral performance and constitutes a computational proposition of the role of the rat prefrontal cortex in strategy shifting. Moreover, such a brain-inspired meta-controller may provide an advancement for learning architectures in robotics. (paper)

  5. Biological control of mosquitoes in scrap tires in Brownsville, Texas, USA and Matamoros, Tamaulipas, Mexico.

    Science.gov (United States)

    Uejio, Christopher K; Hayden, Mary H; Zielinski-Gutierrez, Emily; Lopez, Jose Luis Robles; Barrera, Roberto; Amador, Manuel; Thompson, Gregory; Waterman, Stephen H

    2014-06-01

    Dengue periodically circulates in southern Texas and neighboring Tamaulipas, Mexico; thus, a closer examination of human and vector ecology at the northern limits of North American transmission may improve prevention activities. Scrap tires produce large mosquito populations and increase the risk of dengue transmission. Some households choose not to pay tire disposal fees, and many tires are illegally dumped in residential areas. Biological control may provide low-cost and environmentally friendly mosquito control. This pilot study evaluated the ability of Mesocyclops longisetus to reduce mosquito populations in existing residential scrap tire piles. Mosquito populations were measured by the number of all mosquito pupae within tires or adult Aedes aegypti and Ae. albopictus near piles. Mesocyclops longisetus treated piles did not significantly reduce total mosquito pupae (P = 0.07) in Matamoros, Mexico. The study also evaluated the efficacy of native Toxorhynchites moctezuma which preferentially colonized tire piles under vegetation cover in Brownsville, TX. Toxorhynchites moctezuma larvae significantly reduced total mosquito pupae, but the strength of control diminished over time.

  6. AMIGO2, a toolbox for dynamic modeling, optimization and control in systems biology

    Science.gov (United States)

    Balsa-Canto, Eva; Henriques, David; Gábor, Attila; Banga, Julio R.

    2016-01-01

    Motivation: Many problems of interest in dynamic modeling and control of biological systems can be posed as non-linear optimization problems subject to algebraic and dynamic constraints. In the context of modeling, this is the case of, e.g. parameter estimation, optimal experimental design and dynamic flux balance analysis. In the context of control, model-based metabolic engineering or drug dose optimization problems can be formulated as (multi-objective) optimal control problems. Finding a solution to those problems is a very challenging task which requires advanced numerical methods. Results: This work presents the AMIGO2 toolbox: the first multiplatform software tool that automatizes the solution of all those problems, offering a suite of state-of-the-art (multi-objective) global optimizers and advanced simulation approaches. Availability and Implementation: The toolbox and its documentation are available at: sites.google.com/site/amigo2toolbox. Contact: ebalsa@iim.csic.es Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27378288

  7. Biological control of rice brown spot with native isolates of three Trichoderma species

    Directory of Open Access Journals (Sweden)

    Elham Khalili

    2012-03-01

    Full Text Available Brown spot caused by Bipolaris oryzae is an important rice disease in Southern coast of Caspian Sea, the major rice growing region in Iran. A total of 45 Trichoderma isolates were obtained from rice paddy fields in Golestan and Mazandaran provinces which belonged to Trichoderma harzianum, T. virens and T. atroviride species. Initially, they were screened against B. oryzae by antagonism tests including dual culture, volatile and nonvolatile metabolites and hyperparasitism. Results showed that Trichoderma isolates can significantly inhibit mycelium growth of pathogen in vitro by producing volatile and nonvolatile metabolites Light microscopic observations showed no evidence of mycoparasitic behaviour of the tested isolates of Trichoderma spp. such as coiling around the B. oryzae. According to in vitro experiments, Trichoderma isolates were selected in order to evaluate their efficacy in controlling brown spot in glasshouse using seed treatment and foliar spray methods. Concerning the glasshouse tests, two strains of T. harzianum significantly controlled the disease and one strain of T. atroviride increased the seedling growth. It is the first time that the biological control of rice brown spot and increase of seedling growth with Trichoderma species have been studied in Iran.

  8. Biological control of mosquitoes in scrap tires in Brownsville, Texas, USA and Matamoros, Tamaulipas, Mexico.

    Science.gov (United States)

    Uejio, Christopher K; Hayden, Mary H; Zielinski-Gutierrez, Emily; Lopez, Jose Luis Robles; Barrera, Roberto; Amador, Manuel; Thompson, Gregory; Waterman, Stephen H

    2014-06-01

    Dengue periodically circulates in southern Texas and neighboring Tamaulipas, Mexico; thus, a closer examination of human and vector ecology at the northern limits of North American transmission may improve prevention activities. Scrap tires produce large mosquito populations and increase the risk of dengue transmission. Some households choose not to pay tire disposal fees, and many tires are illegally dumped in residential areas. Biological control may provide low-cost and environmentally friendly mosquito control. This pilot study evaluated the ability of Mesocyclops longisetus to reduce mosquito populations in existing residential scrap tire piles. Mosquito populations were measured by the number of all mosquito pupae within tires or adult Aedes aegypti and Ae. albopictus near piles. Mesocyclops longisetus treated piles did not significantly reduce total mosquito pupae (P = 0.07) in Matamoros, Mexico. The study also evaluated the efficacy of native Toxorhynchites moctezuma which preferentially colonized tire piles under vegetation cover in Brownsville, TX. Toxorhynchites moctezuma larvae significantly reduced total mosquito pupae, but the strength of control diminished over time. PMID:25102598

  9. A biologically inspired meta-control navigation system for the Psikharpax rat robot.

    Science.gov (United States)

    Caluwaerts, K; Staffa, M; N'Guyen, S; Grand, C; Dollé, L; Favre-Félix, A; Girard, B; Khamassi, M

    2012-06-01

    A biologically inspired navigation system for the mobile rat-like robot named Psikharpax is presented, allowing for self-localization and autonomous navigation in an initially unknown environment. The ability of parts of the model (e.g. the strategy selection mechanism) to reproduce rat behavioral data in various maze tasks has been validated before in simulations. But the capacity of the model to work on a real robot platform had not been tested. This paper presents our work on the implementation on the Psikharpax robot of two independent navigation strategies (a place-based planning strategy and a cue-guided taxon strategy) and a strategy selection meta-controller. We show how our robot can memorize which was the optimal strategy in each situation, by means of a reinforcement learning algorithm. Moreover, a context detector enables the controller to quickly adapt to changes in the environment-recognized as new contexts-and to restore previously acquired strategy preferences when a previously experienced context is recognized. This produces adaptivity closer to rat behavioral performance and constitutes a computational proposition of the role of the rat prefrontal cortex in strategy shifting. Moreover, such a brain-inspired meta-controller may provide an advancement for learning architectures in robotics.

  10. The multicolored Asian lady beetle, Harmonia axyridis: A review of its biology, uses in biological control, and non-target impacts

    OpenAIRE

    Koch, R L

    2003-01-01

    Throughout the last century, the multicolored Asian lady beetle, Harmonia axyridis (Pallas) has been studied quite extensively, with topics ranging from genetics and evolution to population dynamics and applied biological control being covered. Much of the early work on H. axyridis was conducted in the native Asian range. From the 1980's to the present, numerous European and North American studies have added to the body of literature on H. axyridis. H. axyridis has recently gained attention i...

  11. Conservation Biological Control and Pest Performance in Lawn Turf: Does Mowing Height Matter?

    Science.gov (United States)

    Dobbs, Emily K.; Potter, Daniel A.

    2014-03-01

    With >80 million United States households engaged in lawn and gardening activities, increasing sustainability of lawn care is important. Mowing height is an easily manipulated aspect of lawn management. We tested the hypothesis that elevated mowing of tall fescue lawn grass promotes a larger, more diverse community of arthropod natural enemies which in turn provides stronger biological control services, and the corollary hypothesis that doing so also renders the turf itself less suitable for growth of insect pests. Turf-type tall fescue was mowed low (6.4 cm) or high (10.2 cm) for two growing seasons, natural enemy populations were assessed by vacuum sampling, pitfall traps, and ant baits, and predation and parasitism were evaluated with sentinel prey caterpillars, grubs, and eggs. In addition, foliage-feeding caterpillars and root-feeding scarab grubs were confined in the turf to evaluate their performance. Although some predatory groups (e.g., rove beetles and spiders) were more abundant in high-mowed grass, predation rates were uniformly high because ants, the dominant predators, were similarly abundant regardless of mowing height. Lower canopy temperatures in high-mowed grass were associated with slower growth of grass-feeding caterpillars. Higher lawn mowing reduces fuel consumption and yard waste, and promotes a deep, robust root system that reduces need for water and chemical inputs. Although in this study elevated mowing height did not measurably increase the already-high levels of predation, it did suggest additional ways through which bottom-up effects on insect pest growth might interact with natural enemies to facilitate conservation biological control.

  12. Postinfection Biological Control of Oomycete Pathogens of Pea by Burkholderia cepacia AMMDR1.

    Science.gov (United States)

    Heungens, K; Parke, J L

    2001-04-01

    ABSTRACT Burkholderia cepacia AMMDR1 is a biocontrol agent that reduces Pythium damping-off and Aphanomyces root rot severity on peas in the field. We studied the effect of B. cepacia AMMDR1 on post-infection stages in the life cycles of these pathogens, including mycelial colonization of the host, production of oogonia, and production of secondary zoospore inoculum. We used Burkholderia cepacia 1324, a seed and rootcolonizing but antibiosis-deficient Tn5 mutant of B. cepacia AMMDR1, to study mechanisms of biological control other than antibiosis. B. cepacia AMMDR1 significantly reduced Pythium aphanidermatum postinfection colonization and damping-off of pea seeds, even when the bacteria were applied 12 h after zoospore inoculation. B. cepacia AMMDR1 also significantly reduced colonization of taproots by Aphanomyces euteiches mycelium, but only when the bacteria were applied at high population densities at the site of zoospore inoculation. The antibiosisdeficient mutant, B. cepacia 1324, had no effect on mycelial colonization of seeds or roots by Pythium aphanidermatum nor A. euteiches, suggesting that antibiosis is the primary mechanism of biological control. B. cepacia AMMDR1, but not B. cepacia 1324, reduced production of A. euteiches oogonia. This effect occurred even when the population size of B. cepacia AMMDR1 was too small to cause a reduction in lesion length early on in the infection process and may result from in situ antibiotic production. B. cepacia AMMDR1 had no effect on the production of secondary zoospores of A. euteiches from infected roots. The main effects of B. cepacia AMMDR1 on postinfection stages in the life cycles of these pathogens therefore were reductions in mycelial colonization by Pythium aphanidermatum and in formation of oogonia by A. euteiches. No mechanism other than antibiosis could be identified. PMID:18943851

  13. Biological weed control with soil fungi? Antagonistic effects of arbuscular mycorrhizal fungi on the growth of weeds

    NARCIS (Netherlands)

    Veiga, R.

    2012-01-01

    Excessive weed growth represents one of the major threats to crop production especially when reliance on herbicides is reduced. Biological weed control is an alternative, environmentally-sound method that, combined with other weed control practices, can contribute to an effective weed management in

  14. Simulating effects of environmental factors on biological control of Tetranychus urticae by Typhlodromus pyri in apple orchards

    NARCIS (Netherlands)

    Hardman, J.M.; Werf, van der W.; Blatt, S.E.; Franklin, J.L.; Karsten, R.; Teismann, H.

    2013-01-01

    Successful biological control of mites is possible under various conditions, and identifying what are the requirements for robust control poses a challenge because interacting factors are involved. Process-based modeling can help to explore these interactions and identify under which conditions biol

  15. Egg Parasitoids from Pakistan as possible classical biological control agents of the invasive pest, Bagrada hilaris (Heteroptera: Pentatomidae)

    Science.gov (United States)

    The newly invasive pest stink bug, Bagrada hilaris, threatens the cole crop industry and certain ornamentals in the U.S. Without its co-evolved natural enemies, it is likely to spread from the Southwest U.S. to the east coast, requiring millions more dollars to control it. If key biological control ...

  16. Biological control of mealybugs with lacewing larvae is affected by the presence and type of supplemental prey

    NARCIS (Netherlands)

    Messelink, Gerben J.; Vijverberg, Roland; Leman, Ada; Janssen, Arne

    2016-01-01

    The diversity of prey and food sources in crops has a major effect on biological pest control by generalist predators. In this study, we tested if and how supplemental prey or food affects the control of the citrus mealybug Planococcus citri (Risso) by larvae of the green lacewing Chrysoperla luc

  17. Rationale for classical biological control of cattle fever ticks and proposed methods for field collection of natural enemies

    Science.gov (United States)

    Classical biological control using specialist parasitoids, predators and/or nematodes from the native ranges of cattle fever ticks Rhipicephalus microplus and Rhipicephalus annulatus could complement existing control strategies for this livestock pest in the transboundary region between Mexico and T...

  18. Detection and reconstruction of error control codes for engineered and biological regulatory systems.

    Energy Technology Data Exchange (ETDEWEB)

    May, Elebeoba Eni; Rintoul, Mark Daniel; Johnston, Anna Marie; Pryor, Richard J.; Hart, William Eugene; Watson, Jean-Paul

    2003-10-01

    A fundamental challenge for all communication systems, engineered or living, is the problem of achieving efficient, secure, and error-free communication over noisy channels. Information theoretic principals have been used to develop effective coding theory algorithms to successfully transmit information in engineering systems. Living systems also successfully transmit biological information through genetic processes such as replication, transcription, and translation, where the genome of an organism is the contents of the transmission. Decoding of received bit streams is fairly straightforward when the channel encoding algorithms are efficient and known. If the encoding scheme is unknown or part of the data is missing or intercepted, how would one design a viable decoder for the received transmission? For such systems blind reconstruction of the encoding/decoding system would be a vital step in recovering the original message. Communication engineers may not frequently encounter this situation, but for computational biologists and biotechnologist this is an immediate challenge. The goal of this work is to develop methods for detecting and reconstructing the encoder/decoder system for engineered and biological data. Building on Sandia's strengths in discrete mathematics, algorithms, and communication theory, we use linear programming and will use evolutionary computing techniques to construct efficient algorithms for modeling the coding system for minimally errored engineered data stream and genomic regulatory DNA and RNA sequences. The objective for the initial phase of this project is to construct solid parallels between biological literature and fundamental elements of communication theory. In this light, the milestones for FY2003 were focused on defining genetic channel characteristics and providing an initial approximation for key parameters, including coding rate, memory length, and minimum distance values. A secondary objective addressed the question of

  19. The role of transient dynamics in biological pest control: insights from a host-parasitoid community.

    Science.gov (United States)

    Kidd, David; Amarasekare, Priyanga

    2012-01-01

    1. Identifying natural enemies that can maintain pests at low abundances is a priority in biological control. Here, we show that experiments combined with models generate new insights into identifying effective control agents prior to their release in the field. Using a host-parasitoid community (the harlequin bug and its egg parasitoids) as a model system, we report three key findings. 2. The interplay between the host's self-limitation and the parasitoids' saturating functional response causes the long-term (steady-state) outcomes for pest suppression to differ from those of short-term (transient) dynamics. When the bug's self-limitation is moderately strong, the parasitoid with the higher attack rate and conversion efficiency (Ooencyrtus) achieves greater host suppression in the long term, but its longer handling time causes long periods of transient dynamics during which the bug can reach high abundances; when the bug's self-limitation is weak, host fluctuations amplify over time and Ooencyrtus fails at host suppression altogether. In contrast, the parasitoid with the lower attack rate and conversion efficiency but the shorter handling time (Trissolcus) induces only weak transient fluctuations of short duration and can maintain the host at low abundances regardless of the strength of the bug's self-limitation. 3. Release of multiple enemy species can compromise host suppression if an enemy that induces stronger transient fluctuations excludes one that induces weaker fluctuations. For instance, Ooencyrtus excludes Trissolcus despite having a longer handling time because of its higher conversion efficiency. The model correctly predicts the time to exclusion observed in experiments, suggesting that it captures the key biological features of the host-parasitoid interaction. 4. Intraspecific interference reduces long-term pest suppression but improves short-term pest control by reducing the magnitude and duration of transient fluctuations. 5. These results highlight

  20. Using counterfactuals to evaluate the cost-effectiveness of controlling biological invasions.

    Science.gov (United States)

    McConnachie, Matthew M; van Wilgen, Brian W; Ferraro, Paul J; Forsyth, Aurelia T; Richardson, David M; Gaertner, Mirijam; Cowling, Richard M

    2016-03-01

    Prioritizing limited conservation funds for controlling biological invasions requires accurate estimates of the effectiveness of interventions to remove invasive species and their cost-effectiveness (cost per unit area or individual). Despite billions of dollars spent controlling biological invasions worldwide, it is unclear whether those efforts are effective, and cost-effective. The paucity of evidence results from the difficulty in measuring the effect of invasive species removal: a researcher must estimate the difference in outcomes (e.g. invasive species cover) between where the removal program intervened and what might have been observed if the program had not intervened. In the program evaluation literature, this is called a counterfactual analysis, which formally compares what actually happened and what would have happened in the absence of an intervention. When program implementation is not randomized, estimating counterfactual outcomes is especially difficult. We show how a thorough understanding of program implementation, combined with a matching empirical design can improve the way counterfactual outcomes are estimated in nonexperimental contexts. As a practical demonstration, we estimated the cost-effectiveness of South Africa's Working for Water program, arguably the world's most ambitious invasive species control program, in removing invasive alien trees from different land use types, across a large area in the Cape Floristic Region. We estimated that the proportion of the treatment area covered by invasive trees would have been 49% higher (5.5% instead of 2.7% of the grid cells occupied) had the program not intervened. Our estimates of cost per hectare to remove invasive species, however, are three to five times higher than the predictions made when the program was initiated. Had there been no control (counter-factual), invasive trees would have spread on untransformed land, but not on land parcels containing plantations or land transformed by

  1. The role of transient dynamics in biological pest control: insights from a host-parasitoid community.

    Science.gov (United States)

    Kidd, David; Amarasekare, Priyanga

    2012-01-01

    1. Identifying natural enemies that can maintain pests at low abundances is a priority in biological control. Here, we show that experiments combined with models generate new insights into identifying effective control agents prior to their release in the field. Using a host-parasitoid community (the harlequin bug and its egg parasitoids) as a model system, we report three key findings. 2. The interplay between the host's self-limitation and the parasitoids' saturating functional response causes the long-term (steady-state) outcomes for pest suppression to differ from those of short-term (transient) dynamics. When the bug's self-limitation is moderately strong, the parasitoid with the higher attack rate and conversion efficiency (Ooencyrtus) achieves greater host suppression in the long term, but its longer handling time causes long periods of transient dynamics during which the bug can reach high abundances; when the bug's self-limitation is weak, host fluctuations amplify over time and Ooencyrtus fails at host suppression altogether. In contrast, the parasitoid with the lower attack rate and conversion efficiency but the shorter handling time (Trissolcus) induces only weak transient fluctuations of short duration and can maintain the host at low abundances regardless of the strength of the bug's self-limitation. 3. Release of multiple enemy species can compromise host suppression if an enemy that induces stronger transient fluctuations excludes one that induces weaker fluctuations. For instance, Ooencyrtus excludes Trissolcus despite having a longer handling time because of its higher conversion efficiency. The model correctly predicts the time to exclusion observed in experiments, suggesting that it captures the key biological features of the host-parasitoid interaction. 4. Intraspecific interference reduces long-term pest suppression but improves short-term pest control by reducing the magnitude and duration of transient fluctuations. 5. These results highlight

  2. Ecological engineering to control bioclogging: an original field study coupling infiltration and biological measurements

    Science.gov (United States)

    Gette-bouvarot, Morgane; Mermillod-Blondin, Florian; Lassabatere, Laurent; Lemoine, Damien; Delolme, Cécile; Volatier, Laurence

    2014-05-01

    Infiltration systems are increasingly used in urban areas for several purposes such as flood prevention and groundwater recharge. However, their functioning is often impacted by clogging that leads to decreases in hydraulic and water treatment performances. These systems are commonly built with sand as infiltration medium, a media subject to rapid clogging by the combined and overlapping processes of pore occlusion by fine particles and biofilm development. In a previous study, we pointed out that the phototrophic component of biofilms developed at the surface layer of infiltration systems (algae, cyanobacteria) could reduce by up to 60-fold the saturated hydraulic conductivity. Consequently, it appears crucial to control biofilm growth to maintain porous infiltration media performances. The present study aimed to test the influence of biotic (addition of animals or macrophytes) and abiotic (light reduction) treatments on biofilm development and associated hydraulic properties in an infiltration device dedicated to aquifer recharge with river water in Lyon Area (France). Twenty-five benthic enclosures were used to test 5 "treatments" on non-manipulated surface layer under field conditions. Three biotic treatments consisted in the introduction of: (i) an invertebrate acting as algae grazer (Viviparus viviparus), (ii) an invertebrate that digs galleries in sediments (Tubifex tubifex), and (iii) a macrophyte that could inhibit benthic biofilm by allelopathic activity (Vallisneria spiralis L). The fourth treatment was designed to simulate shading. The last "treatment" was a control which monitored the evolution of the system during the experiment without manipulation (addition of macro-organisms or shading). Each treatment was replicated five times. The experiment was conducted for 6 weeks, and sampling of the surface layer (0-1 cm) was carried out in each enclosure at the beginning (t0) and the end (tf). We coupled biological characterizations (organic matter, algal

  3. Antibiosis Contributes to Biological Control of Fire Blight by Pantoea agglomerans Strain Eh252 in Orchards.

    Science.gov (United States)

    Stockwell, V O; Johnson, K B; Sugar, D; Loper, J E

    2002-11-01

    ABSTRACT Fire blight, caused by Erwinia amylovora, is the most serious bacterial disease of pear and apple trees. Biological control with strains of Pantoea agglomerans (syn. Erwinia herbicola) may provide an effective disease management strategy for fire blight. Most strains of P. agglomerans evaluated for suppression of fire blight produce compounds that inhibit the growth of E. amylovora in culture. The role of these inhibitory compounds in fire blight suppression in orchard environments has not been studied. In seven field trials in Oregon, we compared the population dynamics and disease suppression with P. agglomerans Eh252, a strain that produces a single antibiotic, with its near-isogenic antibiotic-deficient derivative, strain 10:12. Water or suspensions of Eh252 or 10:12 (1 x 10(8) CFU/ml) were applied at 30 and 70% bloom to pear or apple trees. Aqueous suspensions of freeze-dried cells of E. amylovora (3 x 10(5) CFU/ml) were applied at full bloom. Additional trees were treated with streptomycin or oxytetracycline at 30 and 70% bloom and in some experiments, 1 day after application of the pathogen. Population sizes of Eh252 or 10:12 on pear blossoms were estimated by spreading dilutions of blossom washes on culture media. Average population sizes of Eh252 and 10:12 on blossoms ranged from 10(5) to 10(7) CFU, and in five of six trials, the relative area under the population curve of Eh252 was not significantly different than that of its derivative 10:12. Both Eh252 and 10:12 reduced the growth of the pathogen on blossoms compared with inoculated water-treated controls. Eh252 significantly decreased the incidence of fire blight in six of seven field trials compared with the incidence on water-treated trees, and 10:12 similarly reduced the incidence of fire blight in four of seven trials. In three of seven field trials, trees treated with Eh252 had a significantly lower incidence of fire blight compared with trees treated 3 with 10:12. Overall,3 Eh252 reduced

  4. Biological control of cultural heritage pest Coleoptera and Lepidoptera with the help of parasitoid Hymenoptera

    Directory of Open Access Journals (Sweden)

    Matthias Schöller

    2011-08-01

    Full Text Available Natural enemies are known from many cultural heritage pests, but their potential for biological control has been marginally exploited only. In this publication, examples of practical and commercial application of parasitoids of beetles and moths are compiled as well as laboratory research that contributes to the development of guidelines for parasitoid releases. One the one hand there are parasitoids found to occur simultaneously with the pests in buildings, on the other hand there are parasitoids that were never found to be associated with the respective pests but accept them if brought into the cultural heritage environments. An example for the latter is the egg parasitoid Trichogramma evanescens euproctidis, a parasitoid of moth eggs including those of the cloth moth Tineola bisselliella. In semi-field trials it was shown that inundative releases of the egg parasitoids are necessary and that effectiveness is reduced on thick cloth with long strand. Trichogramma release units have to be placed directly on the cloth to be protected. A naturally occuring parasitoid of Anobiid beetles is the pteromalid larval parasitoid Lariophagus distinguendus. This parasitoid was applied against the drugstore beetle Stegobium paniceum in historic libraries and against spider beetles (Ptininae in historic buildings. A simulation model for the population-dynamics of L. distinguendus and the golden spider beetle Niptus hololeucus is presented. Finally, monitoring of the Braconid larval parasitoid Spathius exarator used for indirect monitoring of the common furniture beetle Anobium punctatum is described. The future potential of parasitoids to control cultural heritage pests is discussed.

  5. Gluconic acid: an antifungal agent produced by Pseudomonas species in biological control of take-all.

    Science.gov (United States)

    Kaur, Rajvinder; Macleod, John; Foley, William; Nayudu, Murali

    2006-03-01

    Pseudomonas strain AN5 (Ps. str. AN5), a non-fluorescent Australian bacterial isolate, is an effective biological control (biocontrol) agent of the take-all disease of wheat caused by the fungus Gaeumannomyces graminis var. tritici (Ggt). Ps. str. AN5 controls Ggt by producing an antifungal compound which was purified by thin layer and column chromatography, and identified by NMR and mass spectroscopic analysis to be d-gluconic acid. Commercially bought pure gluconic acid strongly inhibited Ggt. Two different transposon mutants of Ps. str. AN5 which had lost take-all biocontrol did not produce d-gluconic acid. Gluconic acid production was restored, along with take-all biocontrol, when one of these transposon mutants was complemented with the corresponding open reading frame from wild-type genomic DNA. Gluconic acid was detected in the rhizosphere of wheat roots treated with the wild-type Ps. str. AN5, but not in untreated wheat or wheat treated with a transposon mutant strain which had lost biocontrol. The antifungal compounds phenazine-1-carboxylic acid and 2,4-diacetylphloroglucinol, produced by other Pseudomonads and previously shown to be effective in suppressing the take-all disease, were not detected in Ps. str. AN5 extracts. These results suggest that d-gluconic acid is the most significant antifungal agent produced by Ps. str. AN5 in biocontrol of take-all on wheat roots.

  6. Biological Control of Solenopsis Fire Ants by Pseudacteon Parasitoids: Theory and Practice

    Directory of Open Access Journals (Sweden)

    Lloyd W. Morrison

    2012-01-01

    Full Text Available Pseudacteon parasitoids are potential biocontrol agents of invasive Solenopsis fire ants. Pseudacteon species that parasitize the invasive S. invicta Buren and S. richteri Forel have been introduced to, and naturally dispersed across, the southeastern USA, although there is no evidence yet that Solenopsis host ant populations have decreased. The ability of introduced Pseudacteon species to regulate Solenopsis populations will depend upon the relative importance of top-down effects in the recipient communities. In this paper, I examine the characteristics of the Pseudacteon/Solenopsis parasitoid/host system and evaluate the extent to which research findings are consistent with top-down control. Laboratory and field experiments evaluating Solenopsis population regulation have been equivocal, and overall the available evidence provides little support for strong top-down effects in this system. Competitive exclusion may occur among introduced Pseudacteon species, and future efforts at biological control are likely to be more efficacious if they focus on other types of natural enemies.

  7. Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems

    Science.gov (United States)

    Vitousek, Peter M.; Menge, Duncan N.L.; Reed, Sasha C.; Cleveland, Cory C.

    2013-01-01

    New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)—greatly expanding our appreciation of the diversity and ubiquity of N fixers—but our understanding of the rates and controls of BNF at ecosystem and global scales has not advanced at the same pace. Nevertheless, determining rates and controls of BNF is crucial to placing anthropogenic changes to the N cycle in context, and to understanding, predicting and managing many aspects of global environmental change. Here, we estimate terrestrial BNF for a pre-industrial world by combining information on N fluxes with 15N relative abundance data for terrestrial ecosystems. Our estimate is that pre-industrial N fixation was 58 (range of 40–100) Tg N fixed yr−1; adding conservative assumptions for geological N reduces our best estimate to 44 Tg N yr−1. This approach yields substantially lower estimates than most recent calculations; it suggests that the magnitude of human alternation of the N cycle is substantially larger than has been assumed.

  8. Potential nontarget effects of Metarhizium anisopliae (Deuteromycetes) used for biological control of ticks (Acari: Ixodidae)

    Science.gov (United States)

    Ginsberg, H.S.; LeBrun, R.A.; Heyer, K.; Zhioua, E.

    2002-01-01

    The potential for nontarget effects of the entomopathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin, when used for biological control of ticks, was assessed in laboratory trials. Fungal pathogenicity was studied against convergent ladybird beetles, Hippodamia convergens Guerin-Meneville, house crickets, Acheta domesticus (L.), and milkweed bugs, Oncopeltus fasciatus (Dallas). Fungal spores applied with a spray tower produced significant mortality in H. convergens and A. domesticus, but effects on O. fasciatus were marginal. Treated insects placed with untreated individuals resulted in mortality from horizontal transmission to untreated beetles and crickets, but not milkweed bugs. Spread of fungal infection in the beetles resulted in mortality on days 4-10 after treatment, while in crickets mortality was on day 2 after treatment, suggesting different levels of pathogenicity and possibly different modes of transmission. Therefore, M. anisopliae varies in pathogenicity to different insects. Inundative applications can potentially affect nontarget species, but M. anisopliae is already widely distributed in North America, so applications for tick control generally would not introduce a novel pathogen into the environment. Pathogenicity in lab trials does not, by itself, demonstrate activity under natural conditions, so field trials are needed to confirm these results and to assess methods to minimize nontarget exposure.

  9. Utilizing systems biology to unravel stomatal function and the hierarchies underpinning its control.

    Science.gov (United States)

    Medeiros, David B; Daloso, Danilo M; Fernie, Alisdair R; Nikoloski, Zoran; Araújo, Wagner L

    2015-08-01

    Stomata control the concomitant exchange of CO2 and transpiration in land plants. While a constant supply of CO2 is need to maintain the rate of photosynthesis, the accompanying water losses must be tightly regulated to prevent dehydration and undesired metabolic changes. The factors affecting stomatal movement are directly coupled with the cellular networks of guard cells. Although the guard cell has been used as a model for characterization of signaling pathways, several important questions about its functioning remain elusive. Current modeling approaches describe the stomatal conductance in terms of relatively few easy-to-measure variables being unsuitable for in silico design of genetic manipulation strategies. Here, we argue that a system biology approach, combining modeling and high-throughput experiments, may be used to elucidate the mechanisms underlying stomata control and to determine targets for modulation of stomatal responses to environment. In support of our opinion, we review studies demonstrating how high-throughput approaches have provided a systems-view of guard cells. Finally, we emphasize the opportunities and challenges of genome-scale modeling and large-scale data integration for in silico manipulation of guard cell functions to improve crop yields, particularly under stress conditions which are of pertinence both to climate change and water use efficiency. PMID:25689387

  10. Biological actions of silver nanoparticles embedded in titanium controlled by micro-galvanic effects.

    Science.gov (United States)

    Cao, Huiliang; Liu, Xuanyong; Meng, Fanhao; Chu, Paul K

    2011-01-01

    Titanium embedded with silver nanoparticles (Ag NPs) using a single step silver plasma immersion ion implantation (Ag-PIII) demonstrate micro-galvanic effects that give rise to both controlled antibacterial activity and excellent compatibility with osteoblasts. Scanning electron microscopy (SEM) shows that nanoparticles with average sizes of about 5 nm and 8 nm are formed homogeneously on the titanium surface after undergoing Ag-PIII for 0.5 h and 1 h, respectively. Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) indicate that those nanoparticles are metallic silver produced on and underneath the titanium surface via a local nucleation process from the solid solution of α-Ti(Ag). The Ag-PIII samples inhibit the growth of both Staphylococcus aureus and Escherichia coli while enhancing proliferation of the osteoblast-like cell line MG63. Electrochemical polarization and Zeta potential measurements demonstrate that the low surface toxicity and good cytocompatibility are related to the micro-galvanic effect between the Ag NPs and titanium matrix. Our results show that the physico-chemical properties of the Ag NPs are important in the control of the cytotoxicity and this study opens a new window for the design of nanostructured surfaces on which the biological actions of the Ag NPs can be accurately tailored.

  11. Biological and social influences on cognitive control processes dependent on prefrontal cortex.

    Science.gov (United States)

    Diamond, Adele

    2011-01-01

    Cognitive control functions ("executive functions" [EFs] such as attentional control, self-regulation, working memory, and inhibition) that depend on prefrontal cortex (PFC) are critical for success in school and in life. Many children begin school lacking needed EF skills. Disturbances in EFs occur in many mental health disorders, such as ADHD and depression. This chapter addresses modulation of EFs by biology (genes and neurochemistry) and the environment (including school programs) with implications for clinical disorders and for education. Unusual properties of the prefrontal dopamine system contribute to PFC's vulnerability to environmental and genetic variations that have little effect elsewhere. EFs depend on a late-maturing brain region (PFC), yet they can be improved even in infants and preschoolers, without specialists or fancy equipment. Research shows that activities often squeezed out of school curricula (play, physical education, and the arts) rather than detracting from academic achievement help improve EFs and enhance academic outcomes. Such practices may also head off problems before they lead to diagnoses of EF impairments, including ADHD. Many issues are not simply education issues or health issues; they are both. PMID:21489397

  12. Biological control of late blight of potatoes: In vivo and in vitro evaluation of microbial antagonists against tuber blight.

    OpenAIRE

    Hollywood, J. C.

    2004-01-01

    The cost of losses and control measures attributed to late blight of potatoes caused by Phytophthora infestans, are estimated to exceed {dollar}5 billion annually. Breeding for resistance is difficult owing to the tetraploid genotype of potato and current strains of the pathogen have developed resistance to chemical control. Consequently the search for biological control has assumed greater importance. In this investigation an in vivo bioassay was used to select soils antagonistic to late bli...

  13. Long-term organic farming fosters below and aboveground biota: Implications for soil quality, biological control and productivity

    DEFF Research Database (Denmark)

    Birkhofer, K.; Bezemer, TM; Bloem, J;

    2008-01-01

     Organic farming may contribute substantially to future agricultural production worldwide by improving soil quality and pest control, thereby reducing environmental impacts of conventional farming. We investigated in a comprehensive way soil chemical, as well as below and aboveground biological...... promoting negative environmental impacts of agriculture by reducing internal biological cycles and pest control. On the contrary, organic farming fosters microbial and faunal decomposers and this propagates into the aboveground system via generalist predators thereby increasing conservation biological...... of aboveground herbivore pests (aphids) in these systems. Long-term organic farming and the application of farmyard manure promoted soil quality, microbial biomass and fostered natural enemies and ecosystem engineers, suggesting enhanced nutrient cycling and pest control. Mineral fertilizers and herbicide...

  14. Controversies in modern evolutionary biology: the imperative for error detection and quality control

    Directory of Open Access Journals (Sweden)

    Prosdocimi Francisco

    2012-01-01

    Full Text Available Abstract Background The data from high throughput genomics technologies provide unique opportunities for studies of complex biological systems, but also pose many new challenges. The shift to the genome scale in evolutionary biology, for example, has led to many interesting, but often controversial studies. It has been suggested that part of the conflict may be due to errors in the initial sequences. Most gene sequences are predicted by bioinformatics programs and a number of quality issues have been raised, concerning DNA sequencing errors or badly predicted coding regions, particularly in eukaryotes. Results We investigated the impact of these errors on evolutionary studies and specifically on the identification of important genetic events. We focused on the detection of asymmetric evolution after duplication, which has been the subject of controversy recently. Using the human genome as a reference, we established a reliable set of 688 duplicated genes in 13 complete vertebrate genomes, where significantly different evolutionary rates are observed. We estimated the rates at which protein sequence errors occur and are accumulated in the higher-level analyses. We showed that the majority of the detected events (57% are in fact artifacts due to the putative erroneous sequences and that these artifacts are sufficient to mask the true functional significance of the events. Conclusions Initial errors are accumulated throughout the evolutionary analysis, generating artificially high rates of event predictions and leading to substantial uncertainty in the conclusions. This study emphasizes the urgent need for error detection and quality control strategies in order to efficiently extract knowledge from the new genome data.

  15. Induced Resistance as a Mechanism of Biological Control by Lysobacter enzymogenes Strain C3.

    Science.gov (United States)

    Kilic-Ekici, Ozlem; Yuen, Gary Y

    2003-09-01

    ABSTRACT Induced resistance was found to be a mechanism for biological control of leaf spot, caused by Bipolaris sorokiniana, in tall fescue (Festuca arundinacea) using the bacterium Lysobacter enzymogenes strain C3. Resistance elicited by C3 suppressed germination of B. sorokiniana conidia on the phylloplane in addition to reducing the severity of leaf spot. The pathogen-inhibitory effect could be separated from antibiosis by using heat-inactivated cells of C3 that retained no antifungal activity. Application of live or heat-killed cells to tall fescue leaves resulted only in localized resistance confined to the treated leaf, whereas treatment of roots resulted in systemic resistance expressed in the foliage. The effects of foliar and root applications of C3 were long lasting, as evidenced by suppression of conidial germination and leaf spot development even when pathogen inoculation was delayed 15 days after bacterial treatment. When C3 population levels and germination of pathogen conidia was examined on leaf segments, germination percentage was reduced on all segments from C3-treated leaves compared with segments from non-treated leaves, but no dose-response relationship typical of antagonism was found. Induced resistance by C3 was not host or pathogen specific; foliar application of heat-killed C3 cells controlled B. sorokiniana on wheat and also was effective in reducing the severity of brown patch, caused by Rhizoctonia solani, on tall fescue. Treatments of tall fescue foliage or roots with C3 resulted in significantly elevated peroxidase activity compared with the control.

  16. Rhagoletis cerasi Loew (Diptera: Tephritidae – Biological Characteristics, Harmfulness, and Control

    Directory of Open Access Journals (Sweden)

    Svetomir Stamenković

    2012-01-01

    Full Text Available The European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae, is a highlydestructive pest in sweet and sour cherry orchards with a distribution area throughoutEurope and the temperate regions of Asia. It occurs regularly in all production regions ofthese fruit species in Serbia, damaging up to 10% of cherries in commercial production,while damage can go up to 100% in orchards and on solitary threes unprotected by controlmeasures.In Serbia, European cherry fruit fly most often attacks and damages fruits of the lateripeningcultivars of sweet cherry (Van, Stela, Hedelfinger, Bing, Lambert, Drogan’s Yellow.After a sweet cherry harvest, adults migrate to sour cherry where they continue feedingand ovipositing in half-mature sour cherries (prevailingly the domestic ecotype Oblačinska.During their activity period, larvae damage the fruits, so that they can no longer be consumedeither fresh or processed. The high percentage of sour cherries damaged by R. cerasihas become a factor limiting exports because the intensity of infestation of this fruitexceeds permissible limits. Pesticide use for controlling this pest, especially in integratedproduction, is based on a very poor selection of insecticides which cause problems withresidual ecotoxicity. Consequently, alternative measures for controlling European cherryfruit fly have been intensively studied over the past few years.This work surveys up-to-date results of various studies on the European cherry fruit flyas a very important pest in Serbia and other South and Mid-European countries. The workcontains detailed descriptions of its biological characteristics, flight phenology, infestationintensity and possibilities of fly control in sweet and sour cherry production areas.

  17. Subnuclear organization and trafficking of regulatory proteins: implications for biological control and cancer.

    Science.gov (United States)

    Stein, G S; van Wijnen, A J; Stein, J L; Lian, J B; Montecino, M; Zaidi, K; Javed, A

    2000-01-01

    The regulated and regulatory components that interrelate nuclear structure and function must be experimentally established. A formidable challenge is to define further the control of transcription factor targeting to acceptor sites associated with the nuclear matrix. It will be important to determine whether acceptor proteins are associated with a pre-existing core-filament structural lattice or whether a compositely organized scaffold of regulatory factors is dynamically assembled. An inclusive model for all steps in the targeting of proteins to subnuclear sites cannot yet be proposed. However, this model must account for the apparent diversity of intranuclear targeting signals. It is also important to assess the extent to which regulatory discrimination is mediated by subnuclear domain-specific trafficking signals. Furthermore, the checkpoints that monitor subnuclear distribution of regulatory factors and the sorting steps that ensure both structural and functional fidelity of nuclear domains in which replication and expression of genes occur must be biochemically and mechanistically defined. There is emerging recognition that placement of regulatory components of gene expression must be temporally and spatially coordinated to facilitate biological control. The consequences of breaches in nuclear structure-function relationships are observed in an expanding series of diseases that include cancer [Weis et al., 1994; Rogaia et al., 1997; Yano et al., 1997; Rowley, 1998; Zeng et al., 1998; McNeil et al., 1999; Tao and Levine, 1999a] and neurological disorders [Skinner et al., 1997]. As the repertoire of architecture-associated regulatory factors and cofactors expands, workers in the field are becoming increasingly confident that nuclear organization contributes significantly to control of transcription. To gain increased appreciation for the complexities of subnuclear organization and gene regulation, we must continue to characterize mechanisms that direct

  18. Pochonia chlamydosporia: Advances and Challenges to Improve Its Performance as a Biological Control Agent of Sedentary Endo-parasitic Nematodes

    Science.gov (United States)

    Manzanilla-López, Rosa H.; Esteves, Ivania; Finetti-Sialer, Mariella M.; Hirsch, Penny R.; Ward, Elaine; Devonshire, Jean; Hidalgo-Díaz, Leopoldo

    2013-01-01

    The nematophagous fungus Pochonia chlamydosporia var. chlamydosporia is one of the most studied biological control agents against plant (semi-) endo-parasitic nematodes of the genera Globodera, Heterodera, Meloidogyne, Nacobbus and, more recently, Rotylenchulus. In this paper we present highlights from more than three decades of worldwide research on this biological control agent. We cover different aspects and key components of the complex plant-fungus-nematode tri-trophic interaction, an interaction that needs to be addressed to ensure the efficient use of P. chlamydosporia as a biopesticide as part of an integrated pest management approach. PMID:23589653

  19. Time optimal control of an additional food provided predator-prey system with applications to pest management and biological conservation.

    Science.gov (United States)

    Srinivasu, P D N; Prasad, B S R V

    2010-04-01

    Use of additional food has been widely recognized by experimental scientists as one of the important tools for biological control such as species conservation and pest management. The quality and quantity of additional food supplied to the predators is known to play a vital role in the controllability of the system. The present study is continuation of a previous work that highlights the importance of quality and quantity of the additional food in the dynamics of a predator-prey system in the context of biological control. In this article the controllability of the predator-prey system is analyzed by considering inverse of quality of the additional food as the control variable. Control strategies are offered to steer the system from a given initial state to a required terminal state in a minimum time by formulating Mayer problem of optimal control. It is observed that an optimal strategy is a combination of bang-bang controls and could involve multiple switches. Properties of optimal paths are derived using necessary conditions for Mayer problem. In the light of the results evolved in this work it is possible to eradicate the prey from the eco-system in the minimum time by providing the predator with high quality additional food, which is relevant in the pest management. In the perspective of biological conservation this study highlights the possibilities to drive the state to an admissible interior equilibrium (irrespective of its stability nature) of the system in a minimum time.

  20. Biological control of phytophagous arthropods in the physic nut tree Jatropha curcas L. in Brazil

    Directory of Open Access Journals (Sweden)

    Flávio Lemes Fernandes

    2014-11-01

    Full Text Available Jatropha curcas has a high biofuel oil content, which could replace polluting fuels, and has great potential for large scale monoculture cultivation in the conventional system. We explored the occurrence, spatial distribution and the functional response of the main phytophagous species of this plant and their natural enemies to explore the potential for conservative biological control. We began sampling phytophagous species and predators when J. curcas plants were six months old. The most common species of phytophagous insects were nymphs and adults of Empoasca kraemeri, followed by Frankliniella schultzei and Myzus persicae. Among the predators, Ricoseius loxocheles, Iphiseioides zuluagai, Araneidae, larvae and adults of Psyllobora vigintimaculata and Anthicus sp. were the most frequently encountered. The most common parasitoids were the families Encyrtidae and Braconidae. The highest densities of E. kraemeri and F. schultzei on the edges of the J. curcas crop follow spatial patterns similar to those of their natural enemies I. zuluagai and Anthicus sp. These arthropods can be considered efficient predators of immature stages of E. kraemeri and F. schultzei on J. curcas.

  1. Identification and Characterization of Lysobacter enzymogenes as a Biological Control Agent Against Some Fungal Pathogens

    Institute of Scientific and Technical Information of China (English)

    QIAN Guo-liang; HU Bai-shi; JIANG Ying-hua; LIU Feng-quan

    2009-01-01

    Strain OH11, a Gram-negative, nonspore forming, rod-shaped bacterium with powerful antagonistic activity, was isolated from rhizosphere of green pepper in Jiangsu Academy of Agricultural Sciences of China and characterized to determine its taxonomic position. 16S rRNA gene sequence analysis revealed that strain OH11 belongs to the Gammaproteobacteria and had the highest degree of sequence similarity to Lysobacter enzymogenes strain C3 (AY074793) (99%), Lysobacter enzyrnogenes strain N4-7 (U89965) (99%), Lysobacter antibioticus strain (AB019582) (97%), and Lysobacter gummosus strain (AB16136) (97%). Chemotaxonomic data revealed that strain OH11 possesses a quinine system with Q-8 as the predominant compound and C15:0 iso,C17:1 iso w9c as the predominant iso-branched fatty acids,all of which corroborated the assignment of strain OH11 to the genus Lysobacter. Results of DNA-DNA hybridization and physiological and biochemical tests clearly showed that strain OH11 was classified as Lysobacter enzymogenes. Strain OH11 could produce protease, chitinase, and β-1,3-glucanase. It showed strong in vitro antifungal activity against Rhizoctonia solani, Sclerotinia scletotiorum, and several other phytopathogenic fungi. This is the first report of identification and characterization of Lysobacter enzymogenes as a biological control agent of plant diseases in China.

  2. Biological reference materials for quality control of elemental composition analytical data

    International Nuclear Information System (INIS)

    Twelve biological-matrix, agricultural/food reference materials, Corn Stalk (Zea Mays) (NIST RM 8412), Corn Kernel (Zea Mays) (NIST RM 8413), Bovine Muscle Powder (NIST RM 8414), Whole Egg Powder (NIST RM 8415), Microcrystalline Cellulose (NIST RM 8416), Wheat Gluten (NIST RM 8418), Corn Starch (NIST RM 8432), Corn Bran (NIST RM 8433), Whole Milk Powder (NIST RM 8435), Durum Wheat Flour (NIST RM 8436), Hard Red Spring Wheat Flour (NIST RM 8437) and Soft Winter Wheat Flour (NIST RM 8438) were developed. They were characterized with respect to elemental composition via two extensive international interlaboratory characterization campaigns providing 303 reference and informational concentration values for 34 elements (Al, As, B, Ba, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, F, Fe, Hg, I, K, Mg, Mn, Mo, N, Na, Ni, P, Pb, Rb, S, Sb, Se, Sr, Ti, V, W, Zn) of nutritional, toxicological, and environmental significance. These products are available to the analytical community, for quality control of elemental composition analytical data, from the Standard Reference Materials Program, National Institute of Standards and Technology, Gaithersburg, MD, USA. (author)

  3. Parasitoid Guilds of Agrilus Woodborers (Coleoptera: Buprestidae: Their Diversity and Potential for Use in Biological Control

    Directory of Open Access Journals (Sweden)

    Philip B. Taylor

    2012-01-01

    Full Text Available Literature studies in North America (US and Canada, Europe, and Asia (particularly Russia, China, Japan, and the Korean peninsula were reviewed to identify parasitoid guilds associated with Agrilus woodborers. There are at least 12 species of hymenopteran parasitoids attacking eggs of Agrilus beetles and 56 species (36 genera, attacking Agrilus larvae infesting various host plants in North America, Asia, and Europe. While most of the egg parasitoids (9 species belong to the family Encyrtidae, a majority of the larval parasitoids are members of five families: Braconidae (24 species/11 genera, Eulophidae (8 species/4 genera, Ichneumonidae (10 species/9 genera, and Eupelmidae (6 species/5 genera. The highest rate of Agrilus egg parasitism (>50% was exerted by encyrtid wasps (4 species in North America, Asia, and Europe. In contrast, the highest rate of Agrilus larval parasitism (>50% was caused by species in two genera of braconids: Atanycolus (North America and Spathius (Asia, and one eulophid genus, Tetrastichus (Asia and Europe. Reported rate of Agrilus larval parasitism ichneumonids was frequent in North America, but generally low (<1%. Potential for success in biological control of emerald ash borer (Agrilus planipennis Fairmaire in the USA with North American native parasitoids and old-association Asian parasitoids is discussed.

  4. Enhanced biological control of phytophthora blight of pepper by biosurfactant-producing pseudomonas.

    Science.gov (United States)

    Ozyilmaz, Umit; Benlioglu, Kemal

    2013-12-01

    Pseudomonas isolates from different crop plants were screened for in vitro growth inhibition of Phytophthora capsici and production of biosurfactant. Two in vivo experiments were performed to determine the efficacy of selected Pseudomonas strains against Phytophthora blight of pepper by comparing two fungicide treatments [acibenzolar-S-methyl (ASM) and ASM + mefenoxam]. Bacterial isolates were applied by soil drenching (1 × 10(9) cells/ml), ASM (0.1 μg a.i./ml) and ASM + mefenoxam (0.2 mg product/ml) were applied by foliar spraying, and P. capsici inoculum was incorporated into the pot soil three days after treatments. In the first experiment, four Pseudomonas strains resulted in significant reduction from 48.4 to 61.3% in Phytophthora blight severity. In the second experiment, bacterial treatments combining with olive oil (5 mL per plant) significantly enhanced biological control activity, resulting in a reduction of disease level ranging from 56.8 to 81.1%. ASM + mefenoxam was the most effective treatment while ASM alone was less effective in both bioassays. These results indicate that our Pseudomonas fluorescens strains (6L10, 6ba6 and 3ss9) that have biosurfactant-producing abilities are effective against P. capsici on pepper, and enhanced disease suppression could be achieved when they were used in combination with olive oil. PMID:25288970

  5. Potential of chitinolytic Serratia marcescens strain JPP1 for biological control of Aspergillus parasiticus and aflatoxin.

    Science.gov (United States)

    Wang, Kai; Yan, Pei-Sheng; Cao, Li-Xin; Ding, Qing-Long; Shao, Chi; Zhao, Teng-Fei

    2013-01-01

    Serratia marcescens strain JPP1 was isolated from peanut hulls in Huai'an city, Jiangsu Province, China. Its potential to inhibit the mycelial growth of Aspergillus parasiticus and the subsequent aflatoxin production was evaluated. The strain JPP1 could produce chitinase to degrade fungal cell walls, which was the main mechanism of strain JPP1 for biocontrol. Scanning electron microscopy of fungi treated with the crude chitinase revealed abnormal morphological changes. While the strain was grown in the peanut hulls-based medium, the chitinase activity reached 7.39 units. RT-PCR analysis showed that the crude chitinase repressed the transcription of genes involved in the aflatoxin gene cluster, such as aflR, aflC (pksL1), and aflO (dmtA) genes. By visual agar plate assay and tip culture method, the strain JPP1 exhibited remarkable inhibitory effect on mycelia growth (antifungal ratio >95%) and subsequent aflatoxin production (antiaflatoxigenic ratio >98%). An in vitro assay with seed coating agent of bacterial suspension showed that strain JPP1 effectively reduced fungal growth and subsequent aflatoxin production on peanut seeds, and its antagonistic effect was superior to the common agricultural fungicide of carbendazim. These characteristics suggest that S. marcescens JPP1 strain could potentially be utilized for the biological control of phytopathogenic fungi and aflatoxin in Chinese peanut main producing areas.

  6. Ecological complexity in a coffee agroecosystem: spatial heterogeneity, population persistence and biological control.

    Directory of Open Access Journals (Sweden)

    Heidi Liere

    Full Text Available BACKGROUND: Spatial heterogeneity is essential for the persistence of many inherently unstable systems such as predator-prey and parasitoid-host interactions. Since biological interactions themselves can create heterogeneity in space, the heterogeneity necessary for the persistence of an unstable system could be the result of local interactions involving elements of the unstable system itself. METHODOLOGY/PRINCIPAL FINDINGS: Here we report on a predatory ladybird beetle whose natural history suggests that the beetle requires the patchy distribution of the mutualism between its prey, the green coffee scale, and the arboreal ant, Azteca instabilis. Based on known ecological interactions and the natural history of the system, we constructed a spatially-explicit model and showed that the clustered spatial pattern of ant nests facilitates the persistence of the beetle populations. Furthermore, we show that the dynamics of the beetle consuming the scale insects can cause the clustered distribution of the mutualistic ants in the first place. CONCLUSIONS/SIGNIFICANCE: From a theoretical point of view, our model represents a novel situation in which a predator indirectly causes a spatial pattern of an organism other than its prey, and in doing so facilitates its own persistence. From a practical point of view, it is noteworthy that one of the elements in the system is a persistent pest of coffee, an important world commodity. This pest, we argue, is kept within limits of control through a complex web of ecological interactions that involves the emergent spatial pattern.

  7. Isolation, Characterization, and Identification of Biological Control Agent for Potato Soft Rot in Bangladesh

    Directory of Open Access Journals (Sweden)

    M. M. Rahman

    2012-01-01

    Full Text Available A total of 91 isolates of probable antagonistic bacteria of potato soft rot bacterium Erwinia carotovora subsp. carotovora (Ecc were extracted from rhizospheres and endophytes of various crop plants, different soil varieties, and atmospheres in the potato farming areas of Bangladesh. Antibacterial activity of the isolated probable antagonistic bacteria was tested in vitro against the previously identified most common and most virulent soft rot causing bacterial strain Ecc P-138. Only two isolates E-45 and E-65 significantly inhibited the in vitro growth of Ecc P-138. Physiological, biochemical, and carbon source utilization tests identified isolate E-65 as a member of the genus Bacillus and the isolate E-45 as Lactobacillus sp. The stronger antagonistic activity against Ecc P-138 was found in E-65 in vitro screening and storage potatoes. E-65 reduced the soft rot infection to 22-week storage potatoes of different varieties by 32.5–62.5% in model experiment, demonstrating its strong potential to be used as an effective biological control agent for the major pectolytic bacteria Ecc. The highest (62.5% antagonistic effect of E-65 was observed in the Granola and the lowest (32.7% of that was found in the Cardinal varieties of the Bangladeshi potatoes. The findings suggest that isolate E-65 could be exploited as a biocontrol agent for potato tubers.

  8. Invading freshwater snails and biological control in Martinique Island, French West Indies

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Pointier

    2001-09-01

    Full Text Available Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp., three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera and one ampullarid (Marisa cornuarietis. Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis.

  9. Disease control by chemical and biological fungicides in cultivated mushrooms: button mushroom, oyster mushroom and shiitake

    Directory of Open Access Journals (Sweden)

    Ivana Potočnik

    2015-12-01

    Full Text Available The most commonly cultivated basidiomycetes worldwide and in Serbia are button mushroom (Agaricus bisporus, oyster mushroom (Pleurotus sp. and shiitake (Lentinus edodes. Production of their fruiting bodies is severely afflicted by fungal, bacterial, and viral pathogens that are able to cause diseases which affect yield and quality. Major A. bisporus fungal pathogens include Mycogone perniciosa, Lecanicillium fungicola, and Cladobotryum spp., the causal agents of dry bubble, wet bubble, and cobweb disease, respectively. Various Trichoderma species, the causal agents of green mould, also affect all three kinds of edible mushrooms. Over the past two decades, green mould caused by T. aggressivum has been the most serious disease of button mushroom. Oyster mushroom is susceptible to T. pleurotum and shiitake to T. harzianum. The bacterial brawn blotch disease, caused by Pseudomonas tolaasii, is distributed globally. Disease control on mushroom farms worldwide is commonly based on the use of fungicides. However, evolution of pathogen resistance to fungicides after frequent application, and host sensitivity to fungicides are serious problems. Only a few fungicides are officially recommended in mushroom production: chlorothalonil and thiabendazol in North America and prochloraz in the EU and some other countries. Even though decreased sensitivity levels of L. fungicola and Cladobotryum mycophilum to prochloraz have been detected, disease control is still mainly provided by that chemical fungicide. Considering such resistance evolution, harmful impact to the environment and human health, special attention should be focused on biofungicides, both microbiological products based on Bacillus species and various natural substances of biological origin, together with good programs of hygiene. Introduction of biofungicides has created new possibilities for crop protection with reduced application of chemicals.

  10. Biological Control of Rice Bakanae by an Endophytic Bacillus oryzicola YC7007.

    Science.gov (United States)

    Hossain, Mohammad Tofajjal; Khan, Ajmal; Chung, Eu Jin; Rashid, Md Harun-Or; Chung, Young Ryun

    2016-06-01

    In our previous study, we reported that a novel endophytic bacterium Bacillus oryzicola YC7007 has suppressed bacterial diseases of rice via induced systemic resistance and antibiotic production. This endophytic strain, B. oryzicola YC7007 was used as a biological control agent against bakanae disease of rice caused by Fusarium fujikuroi, and its mechanism of interaction with the pathogen and the rice was further elucidated. Root drenching with B. oryzicola YC7007 suspension reduced the disease severity of bakanae significantly when compared with the untreated controls. The treatments of B. oryzicola YC7007 suspension (2.0 × 10(7) cfu/ml) to the rice rhizosphere reduced bakanae severity by 46-78% in pots and nursery box tests containing autoclaved and non-autoclaved soils. Moreover, in the detached rice leaves bioassay, the development of necrotic lesion and mycelial expansion of F. fujikuroi were inhibited significantly by spraying the culture filtrate of B. oryzicola YC7007. Drenching of ethyl acetate extracts of the culture filtrate to the rhizosphere of rice seedlings also reduced the bakanae disease severity in the plant culture dish tests. With the root drenching of B. oryzicola YC7007 suspension, the accumulation of hydrogen peroxide was observed at an early stage of rice seedlings, and a hormonal defense was elicited with and without pathogen inoculation. Our results showed that the strain B. oryzicola YC7007 had a good biocontrol activity against the bakanae disease of rice by direct inhibition, and was also capable of inducing systemic resistance against the pathogen via primed induction of the jasmonic acid pathway. PMID:27298598

  11. Characterizing CMN1308, a Novel Strain of Bacillus amyloliquefaciens, for Potential Biological Control Application

    Directory of Open Access Journals (Sweden)

    Xuehua ZHANG

    2016-06-01

    Full Text Available Fungal diseases of plants continue to contribute to heavy crop losses in spite of the best control efforts of plant pathologists. Breeding for disease-resistant varieties and the application of synthetic chemical fungicides are the most widely accepted approaches in plant disease management. CMN1308 strain of Bacillus amyloliquefaciens was isolated from healthy Chinese chestnut fruit, which has antibiosis and induced resistance to the prevention mechanism of pathogenic bacterium after picking. In order to evaluate the antibiosis mechanism, CMN1308 was fostered with the method of confront culture. The antimicrobial components were also isolated from the culture of CMN1308, and their stability and antimicrobial activity was tested under different treatments such as temperature, pH and UV. The results showed that CMN1308 displays advantages in regard to spatial competition against the major pathogens of chestnut, Rhizopus stolonifer, Fusarium solani, Stachybotrys chartarum, Cryphonectria parasitica, Lasiodiplodia theobromae, Penicillium expansum and Aspergillus niger. Among this, CMN1308 had the best antimicrobial activity against P. expansum, with the inhibition zone diameter of 27.1 mm. The antimicrobial material isolated from CMN1308 culture showed a strong inhibition to the growth of P. expansum hyphal and also had a good stability to high temperature, alkali media and UV, but was sensitive to acidic conditions. Furthermore, CMN1308 increased the peroxidase, polyphenol oxidase activity and reduced the MDA content in chestnuts after infecting by pathogenic fungi. Thus, producing antibiotic compounds and inducible resistance are the main factors that may explain the antibacterial mechanism of CMN1308 on chestnut pathogenic. The results of this study might help to optimize the practical use of CMN1308 in the biological control of chestnut rot or other fruit rot infected by pathogenic fungi.

  12. Biological Control of Rice Bakanae by an Endophytic Bacillus oryzicola YC7007

    Directory of Open Access Journals (Sweden)

    Mohammad Tofajjal Hossain

    2016-06-01

    Full Text Available In our previous study, we reported that a novel endophytic bacterium Bacillus oryzicola YC7007 has suppressed bacterial diseases of rice via induced systemic resistance and antibiotic production. This endophytic strain, B. oryzicola YC7007 was used as a biological control agent against bakanae disease of rice caused by Fusarium fujikuroi, and its mechanism of interaction with the pathogen and the rice was further elucidated. Root drenching with B. oryzicola YC7007 suspension reduced the disease severity of bakanae significantly when compared with the untreated controls. The treatments of B. oryzicola YC7007 suspension (2.0 × 10⁷ cfu/ml to the rice rhizosphere reduced bakanae severity by 46–78% in pots and nursery box tests containing autoclaved and non-autoclaved soils. Moreover, in the detached rice leaves bioassay, the development of necrotic lesion and mycelial expansion of F. fujikuroi were inhibited significantly by spraying the culture filtrate of B. oryzicola YC7007. Drenching of ethyl acetate extracts of the culture filtrate to the rhizosphere of rice seedlings also reduced the bakanae disease severity in the plant culture dish tests. With the root drenching of B. oryzicola YC7007 suspension, the accumulation of hydrogen peroxide was observed at an early stage of rice seedlings, and a hormonal defense was elicited with and without pathogen inoculation. Our results showed that the strain B. oryzicola YC7007 had a good biocontrol activity against the bakanae disease of rice by direct inhibition, and was also capable of inducing systemic resistance against the pathogen via primed induction of the jasmonic acid pathway.

  13. Construction of biological control strain of Trichoderma viride and study of their ability to induce plant disease resistance

    Institute of Scientific and Technical Information of China (English)

    LIU Shi-wang; GUO Ze-jian

    2004-01-01

    @@ Plant diseases heavily affct plant growth and crop yield even in modern agriculture. Control its difficult because pathogens mutate frequently, and this leads in frequent breaking of disease resistance in commercial cultivars. The excessive application of chemical pesticides is not only producing pesticideresistant pathogens, but it is harming the environment threatening the health of human beings.Therefore, the use of biological control agents (BCA) may provide an environmental friendly alternative to chemicals for plant disease control. Hypersensitive response (HR) and systemic acquired resistance (SAR) are the typical expressions of plant defense reactions. Once SAR is established,, the plants exhibits a broad-spectrum of disease resistance against pathogen attack. Researchers have identified elicitor proteins, such as elicitins and harpins, which activate plant defense reactions. It would be useful to explore the possibility of using biological control agents to induce a status of SAR in crop plants.

  14. Life history and host range of Oxydia vesulia transpeneus, an unsuitable biological control agent of Brazilian peppertree

    Science.gov (United States)

    The suitability of Oxydia vesulia (Cramer) (Lepidoptera: Geometridae) was assessed as a potential biological control agent of the invasive weed Brazilian Peppertree Schinus terebinthifolia. Larvae were collected in Brazil feeding on the plant in its native range and colonized in quarantine where lif...

  15. Microsporidian and viral pathogens for the biological control of imported fire ants: can we walk the talk?

    Science.gov (United States)

    . Invasive ants are among the most serious of arthropod invaders. These ants infest a wide range of habitats and impact biodiversity, agriculture, and human health. Self-sustaining biological control is one of the few hopes for permanent regional suppression of these established invasive ants. Fo...

  16. Release and distribution of Lilioceris cheni (Coleoptera: Chrysomelidae), a biological control agent of air potato (Dioscorea bulbilfera: Dioscoreaceae), in Florida

    Science.gov (United States)

    From 2012 to 2015, 429,668 Lilioceris cheni Gressit and Kimoto (Coleoptera: Chrysomelidae) were released in Florida for biological control of air potato [Dioscorea bulbilfera L. (Dioscoreaceae)]. The spatial distribution of releases was highly aggregated, with several areas of high density releases ...

  17. Long-term organic farming fosters below and aboveground biota: Implications for soil quality, biological control and productivity

    OpenAIRE

    Birkhofer, Klaus; Bezemer, TM; . Bloem, J.; Bonkowski, M.; Christensen, S; Dubois, David; Ekelund , F; Fließbach, Andreas; Gunst, Lucie; K. Hedlund; Mäder, Paul; Mikola, J.; Robin, C.; Setälä, Heikki; Tatin-Froux , F

    2008-01-01

    Organic farming may contribute substantially to future agricultural production worldwide by improving soil quality and pest control, thereby reducing environmental impacts of conventional farming. We investigated in a comprehensive way soil chemical, as well as below and aboveground biological parameters of two organic and two conventional wheat farming systems that primarily differed in fertilization and weed management strategies. Contrast analyses identified management related differences ...

  18. Long-term organic farming fosters below- and aboveground biota: Implications for soil quality, biological control and productivity

    OpenAIRE

    Birkhofer, K.; Bezemer, TM; . Bloem, J.; Bonkowski, M.; Christensen, S; Dubois, D; Ekelund , F; Fließbach, A.; Gunst , L; K. Hedlund; Mäder, P.; Mikola, J.; Robin, C.; Setälä , H; Tatin-Froux , F

    2008-01-01

    Organic farming may contribute substantially to future agricultural production worldwide by improving soil quality and pest control, thereby reducing environmental impacts of conventional farming. We investigated in a comprehensive way soil chemical, as well as below and aboveground biological parameters of two organic and two conventional wheat farming systems that primarily differed in fertilization and weed management strategies. Contrast analyses identified management related differenc...

  19. Long-term organic farming fosters below- and aboveground biota: Implications for soil quality, biological control, and productivity

    OpenAIRE

    Birkhofer, Klaus; Bezemer, T. Martijn; Bloem, Jaap; Bonkowski, Michael; Christensen, Søren; Dubois, David; Ekelund, Fleming; Fließbach, Andreas; Gunst, Lucie; Hedlund, Katarina; Mäder, Paul; Mikola, Juha; Robin, Christophe; Setälä, Heikki; Tatin-Froux, Fabienne

    2008-01-01

    Organic farming may contribute substantially to future agricultural production worldwide by improving soil quality and pest control, thereby reducing environmental impacts of conventional farming. We investigated in a comprehensive way soil chemical, as well as below and aboveground biological parameters of two organic and two conventional wheat farming systems that primarily differed in fertilization and weed management strategies. Contrast analyses identified management related differences ...

  20. Whole-Genome Sequence of Pseudomonas graminis Strain UASWS1507, a Potential Biological Control Agent and Biofertilizer Isolated in Switzerland

    Science.gov (United States)

    Crovadore, Julien; Calmin, Gautier; Chablais, Romain; Cochard, Bastien; Schulz, Torsten

    2016-01-01

    We report here the whole-genome shotgun sequence of the strain UASWS1507 of the species Pseudomonas graminis, isolated in Switzerland from an apple tree. This is the first genome registered for this species, which is considered as a potential and valuable resource of biological control agents and biofertilizers for agriculture.

  1. Virtual Agonist-antagonist Mechanisms Produce Biological Muscle-like Functions: An Application for Robot Joint Control

    DEFF Research Database (Denmark)

    Xiong, Xiaofeng; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    Purpose – Biological muscles of animals have a surprising variety of functions, i.e., struts, springs, and brakes. According to this, the purpose of this paper is to apply virtual agonist-antagonist mechanisms to robot joint control allowing for muscle-like functions and variably compliant joint...

  2. Modelling biological control with wild-type and genetically modified baculoviruses in the Helicoverpa armigera-cotton system

    NARCIS (Netherlands)

    Sun, X.; Werf, van der W.; Bianchi, F.J.J.A.; Hu, Z.; Vlak, J.M.

    2006-01-01

    A comprehensive model was developed to simulate virus epizootics in a stage structured insect population and analyse scenarios for the biological control of cotton bollworm (CBW), Helicoverpa armigera, in cotton, using wild-type or genetically modified baculoviruses. In simulations on dosage and tim

  3. The Potential Role of Nuclear Techniques in Support of the Production of Biological Control Agents of Insect Pests

    International Nuclear Information System (INIS)

    While nuclear techniques could play a vital role in enabling cost-effective mass production of beneficial insects for use in augmentative biological control, surprisingly little use has been made of these techniques or ionizing radiation produced by other means (e.g., x-rays or electron beams from linear accelerators) for mass rearing beneficial insects. This technology has been available for quite some time, having been used to reproductively sterilize screwworm flies as early as 1951 (Bushland and Hopkins). Similarly, gamma radiation has been accepted internationally for human food preservation and disinfestation for many years (Anon., 1995). Quite a number of gamma radiation sources exist at or near USDA ARS and APHIS facilities throughout the U.S., as well as in many universities. Still, relatively little use has been made of this approach to assist in mass rearing of beneficial insects for use in augmentative biological control. As pointed out by Benbrook (1996), pest management is at a crossroads, and there still is a great need for new, biointensive pest management strategies. Nuclear techniques should play an increasing role in the future, as the overall thrust of biological control moves more and more toward augmentative releases (Knipling, 1992). It is the intent of this presentation to review some of the existing and potential uses that can be made of nuclear techniques and other sources of ionizing radiation in support of the biological control of insect pests. (author)

  4. Understanding biological control of greenhouse whitefly with the parasitoid Encarsia formosa. From individual behaviour to population dynamics.

    NARCIS (Netherlands)

    Roermund, van H.J.W.

    1995-01-01

    The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae), is a very common, highly polyphagous pest insect all over the world. Biological control of whiteflies with the parasitoid Encarsia formosa Gahan (Hymenoptera, Aphelinidae) was already applied in the 1920s in Engl

  5. Biological control of beet armyworm, Spodoptera exigua, with baculoviruses in greenhouses : development of a comprehensive process-based model

    NARCIS (Netherlands)

    Bianchi, F.J.J.A.; Vlak, J.M.; Rabbinge, R.; Werf, van der W.

    2002-01-01

    We describe the development of a comprehensive process-based model simulating the epizootiology and agronomic efficacy of baculoviruses used for biological control of beet armyworm, Spodoptera exigua, in greenhouse chrysanthemum. The model is built to help understand, evaluate, and predict the effec

  6. Biological soil disinfestation (BSD), a new control method for potato brown rot, caused by Ralstonia solanacearum race 3 biovar 2

    NARCIS (Netherlands)

    Messiha, N.A.S.; Diepeningen, van A.D.; Wenneker, M.; Beuningen, van A.R.; Janse, J.D.; Coenen, G.C.M.; Termorshuizen, A.J.; Bruggen, van A.H.C.; Blok, W.J.

    2007-01-01

    The potential of Biological Soil Disinfestation (BSD) to control potato brown rot, caused by Ralstonia solanacearum race 3 biovar 2, was investigated. BSD involves the induction of anaerobic soil conditions by increasing microbial respiration through incorporation of fresh organic amendments (here:

  7. Are three colonies of Neostromboceros albicomus, a candidate biological control agent for Lygodium microphyllum, the same host biotype?

    Science.gov (United States)

    Three colonies of Neostromboceros albicomus, a candidate biological control agent of Lygodium microphyllum, were barcoded using the D2 expansion domain, to determine which of two biotypes they represented. The first colony, collected in 2005 & 2007, was used for the initial host range testing. Colon...

  8. Phenology and temperature-dependent development of Ceutorhynchus assimilis, a potential biological control agent for Lepidium draba

    Science.gov (United States)

    Heart-podded hoary cress (Lepidium draba) is an alien weed that has invaded rangeland in the northwestern USA. A host race (i;e; host-specific biotype) of the weevil, Ceutorhynchus assimilis, is being evaluated as a prospective biological control agent. This biotype is only known from southern Eur...

  9. The prospect of applying chemical elicitors and plant strengtheners to enhance the biological control of crop pests

    OpenAIRE

    Sobhy, Islam S.; Erb, Matthias; Lou, Yonggen; Ted C J Turlings

    2014-01-01

    An imminent food crisis reinforces the need for novel strategies to increase crop yields worldwide. Effective control of pest insects should be part of such strategies, preferentially with reduced negative impact on the environment and optimal protection and utilization of existing biodiversity. Enhancing the presence and efficacy of native biological control agents could be one such strategy. Plant strengthener is a generic term for several commercially available compounds or mixtures of com...

  10. The effect of biological and chemical control agents on the health status of the very early potato cultivar Rosara

    OpenAIRE

    Cwalina-Ambroziak Bożena; Damszel Marta Maria; Głosek-Sobieraj Małgorzata

    2015-01-01

    The external appearance and quality of table potatoes are determined, among other factors, by the health status of the plants during the growing season. Chemical control methods are often combined with biocontrol agents to effectively fight potato pathogens. Potatoes of the very early cultivar Rosara were grown in experimental plots. The plots were located in Tomaszkowo (NE Poland, 2007-2009). The experiment involved the following treatments: 1) biological control − mycorrhizal Glomus spp. in...

  11. From the ancient times of the agriculture to the biological control in plants: a little of the history

    OpenAIRE

    Maria Margareth Zamboni Pinotti; Julio Cesar Pires Santos

    2013-01-01

    The advancement of technology in agriculture driven by the need to increase efficiency in production transformed agriculture in an eminently anti-ecological activity, with large-scale use of industrialized products. Human beans still live the paradigm of agriculture based on the use of chemical inputs, which often brings harmful consequences to the environment. As an alternative to u the use of pesticides to control pests and diseases, biological control is a practice that has been increasing...

  12. Biological Control of Lettuce Drop and Host Plant Colonization by Rhizospheric and Endophytic Streptomycetes.

    Science.gov (United States)

    Chen, Xiaoyulong; Pizzatti, Cristina; Bonaldi, Maria; Saracchi, Marco; Erlacher, Armin; Kunova, Andrea; Berg, Gabriele; Cortesi, Paolo

    2016-01-01

    Lettuce drop, caused by the soil borne pathogen Sclerotinia sclerotiorum, is one of the most common and serious diseases of lettuce worldwide. Increased concerns about the side effects of chemical pesticides have resulted in greater interest in developing biocontrol strategies against S. sclerotiorum. However, relatively little is known about the mechanisms of Streptomyces spp. as biological control agents against S. sclerotiorum on lettuce. Two Streptomyces isolates, S. exfoliatus FT05W and S. cyaneus ZEA17I, inhibit mycelial growth of Sclerotinia sclerotiorum by more than 75% in vitro. We evaluated their biocontrol activity against S. sclerotiorum in vivo, and compared them to Streptomyces lydicus WYEC 108, isolated from Actinovate®. When Streptomyces spp. (10(6) CFU/mL) were applied to S. sclerotiorum inoculated substrate in a growth chamber 1 week prior lettuce sowing, they significantly reduced the risk of lettuce drop disease, compared to the inoculated control. Interestingly, under field conditions, S. exfoliatus FT05W and S. cyaneus ZEA17I protected lettuce from drop by 40 and 10% respectively, whereas S. lydicus WYEC 108 did not show any protection. We further labeled S. exfoliatus FT05W and S. cyaneus ZEA17I with the enhanced GFP (EGFP) marker to investigate their rhizosphere competence and ability to colonize lettuce roots using confocal laser scanning microscopy (CLSM). The abundant colonization of young lettuce seedlings by both strains demonstrated Streptomyces' capability to interact with the host from early stages of seed germination and root development. Moreover, the two strains were detected also on 2-week-old roots, indicating their potential of long-term interactions with lettuce. Additionally, scanning electron microscopy (SEM) observations showed EGFP-S. exfoliatus FT05W endophytic colonization of lettuce root cortex tissues. Finally, we determined its viability and persistence in the rhizosphere and endorhiza up to 3 weeks by quantifying

  13. Biological control of lettuce drop and host plant colonization by rhizospheric and endophytic streptomycetes

    Directory of Open Access Journals (Sweden)

    Xiaoyulong eChen

    2016-05-01

    Full Text Available Lettuce drop, caused by the soil borne pathogen Sclerotinia sclerotiorum, is one of the most common and serious diseases of lettuce worldwide. Increased concerns about the side effects of chemical pesticides have resulted in greater interest in developing biocontrol strategies against S. sclerotiorum. However, relatively little is known about the mechanisms of Streptomyces spp. as biological control agents against S. sclerotiorum on lettuce. Two Streptomyces isolates, S. exfoliatus FT05W and S. cyaneus ZEA17I, inhibit mycelial growth of Sclerotinia sclerotiorum by more than 75% in vitro. We evaluated their biocontrol activity against S. sclerotiorum in vivo, and compared them to Streptomyces lydicus WYEC 108, isolated from Actinovate®. When Streptomyces spp. (106 CFU/mL were applied to S. sclerotiorum inoculated substrate in a growth chamber one week prior lettuce sowing, they significantly reduced the risk of lettuce drop disease, compared to the inoculated control. Interestingly, under field conditions, S. exfoliatus FT05W and S. cyaneus ZEA17I protected lettuce from drop by 40% and 10% respectively, whereas S. lydicus WYEC 108 did not show any protection. We further labeled S. exfoliatus FT05W and S. cyaneus ZEA17I with the enhanced GFP (EGFP marker to investigate their rhizosphere competence and ability to colonize lettuce roots using confocal laser scanning microscopy (CLSM. The abundant colonization of young lettuce seedlings by both strains demonstrated Streptomyces’ capability to interact with the host from early stages of seed germination and root development. Moreover, the two strains were detected also on two-week-old roots, indicating their potential of long-term interactions with lettuce. Additionally, scanning electron microscopy (SEM observations showed EGFP-S. exfoliatus FT05W endophytic colonization of lettuce root cortex tissues. Finally, we determined its viability and persistence in the rhizosphere and endorhiza up to

  14. Biological soil disinfestation : a safe and effective approach for controlling soilborne pests and diseases

    NARCIS (Netherlands)

    Lamers, J.G.; Wanten, P.J.; Blok, W.J.

    2004-01-01

    Biological soil disinfestation (bsd) is an environmentally friendly method to disinfest the soil from soilborne fungi and nematodes. With biological soil disinfestation a green manure crop (40 tonnes per ha) or other green biomass is homogeneously incorporated into the soil layer that has to be disi

  15. Genes expressed by the biological control bacterium Pseudomonas protegens Pf-5 on seed surfaces under the control of the global regulators GacA and RpoS

    Science.gov (United States)

    The GacA/Rsm signal transduction system and the stationary phase sigma factor RpoS have both been shown to affect secondary metabolite production and biological control in Pseudomonas protegens Pf-5 and related strains. Microarray analysis of Pf-5 grown on pea seed surfaces showed that 595 genes ar...

  16. The use of compost for the biological pest control. An alternative for pesticides; Utilizacion de compost en el control biologico de plagas. Una alternativa a los plaguicidas quimicos

    Energy Technology Data Exchange (ETDEWEB)

    Pascual, J. A.

    2000-07-01

    Traditional methods of controlling pests and diseases using chemical pesticides can provide highly effective pest control but these methods might be damaging to the environment. Compost or other organic matter added to soil has the potential to control many soil borne plant pathogens, therefore they can be used in the sustainable agriculture. The mechanisms of action of compost are not well defined, being a mix of mycoparasitism, antibiotic production and nutrient competition. Our research is focused on the potential action of compost from municipal wastes in the biological control on pest. The addition of organic waste compost improved the biological control against Pythium furthermore raised the organic matter content of an arid soil. The addition of urban waste to the soil also could act long-term against Pythium, reducing the application times. One of the compost fraction more active in biological control are the humic substances. Nowadays, composts cannot be used by themselves to prevent plant pathogens action, it also is needed some pesticide application, but the use of these pesticides can be considerably reduced with the application of compost. (Author)

  17. Optimal Plant Carbon Allocation Implies a Biological Control on Nitrogen Availability

    Science.gov (United States)

    Prentice, I. C.; Stocker, B. D.

    2015-12-01

    The degree to which nitrogen availability limits the terrestrial C sink under rising CO2 is a key uncertainty in carbon cycle and climate change projections. Results from ecosystem manipulation studies and meta-analyses suggest that plant C allocation to roots adjusts dynamically under varying degrees of nitrogen availability and other soil fertility parameters. In addition, the ratio of biomass production to GPP appears to decline under nutrient scarcity. This reflects increasing plant C exudation into the soil (Cex) with decreasing nutrient availability. Cex is consumed by an array of soil organisms and may imply an improvement of nutrient availability to the plant. Thus, N availability is under biological control, but incurs a C cost. In spite of clear observational support, this concept is left unaccounted for in Earth system models. We develop a model for the coupled cycles of C and N in terrestrial ecosystems to explore optimal plant C allocation under rising CO2 and its implications for the ecosystem C balance. The model follows a balanced growth approach, accounting for the trade-offs between leaf versus root growth and Cex in balancing C fixation and N uptake. We assume that Cex is proportional to root mass, and that the ratio of N uptake (Nup) to Cex is proportional to inorganic N concentration in the soil solution. We further assume that Cex is consumed by N2-fixing processes if the ratio of Nup:Cex falls below the inverse of the C cost of N2-fixation. Our analysis thereby accounts for the feedbacks between ecosystem C and N cycling and stoichiometry. We address the question of how the plant C economy will adjust under rising atmospheric CO2 and what this implies for the ecosystem C balance and the degree of N limitation.

  18. Seed preferences by rodents in the agri-environment and implications for biological weed control.

    Science.gov (United States)

    Fischer, Christina; Türke, Manfred

    2016-08-01

    Post-dispersal seed predation and endozoochorous seed dispersal are two antagonistic processes in relation to plant recruitment, but rely on similar preconditions such as feeding behavior of seed consumers and seed traits. In agricultural landscapes, rodents are considered important seed predators, thereby potentially providing regulating ecosystem services in terms of biological weed control. However, their potential to disperse seeds endozoochorously is largely unknown. We exposed seeds of arable plant species with different seed traits (seed weight, nutrient content) and different Red List status in an experimental rye field and assessed seed removal by rodents. In a complementary laboratory experiment, consumption rates, feeding preferences, and potential endozoochory by two vole species (Microtus arvalis and Myodes glareolus) were tested. Seed consumption by rodents after 24 h was 35% in the field and 90% in the laboratory. Both vole species preferred nutrient-rich over nutrient-poor seeds and M. glareolus further preferred light over heavy seeds and seeds of common over those of endangered plants. Endozoochory by voles could be neglected for all tested plant species as no seeds germinated, and only few intact seeds could be retrieved from feces. Synthesis and applications. Our results suggest that voles can provide regulating services in agricultural landscapes by depleting the seed shadow of weeds, rather than facilitating plant recruitment by endozoochory. In the laboratory, endangered arable plants were less preferred by voles than noxious weeds, and thus, our results provide implications for seed choice in restoration approaches. However, other factors such as seed and predator densities need to be taken into account to reliably predict the impact of rodents on the seed fate of arable plants. PMID:27547355

  19. The first characterization of gene structure and biological function for echinoderm translationally controlled tumor protein (TCTP).

    Science.gov (United States)

    Ren, Chunhua; Chen, Ting; Jiang, Xiao; Wang, Yanhong; Hu, Chaoqun

    2014-12-01

    Translationally controlled tumor protein (TCTP) is a multifunctional protein that existed ubiquitously in different eukaryote species and distributed widely in various tissues and cell types. In this study, the gene structure and biological function of TCTP were first characterized in echinoderm. An echinoderm TCTP named StmTCTP was identified from sea cucumber (Stichopus monotuberculatus) by expression sequence tag (EST) analysis and rapid amplification of cDNA ends (RACE) approach. The StmTCTP cDNA is 1219 bp in length, containing a 5'-untranslated region (UTR) of 77 bp, a 3'-UTR of 623 bp and an open reading frame (ORF) of 519 bp that encoding a protein of 172 amino acids with a deduced molecular weight of 19.80 kDa and a predicted isolectric point of 4.66. Two deduced signal signatures termed TCTP1 and TCTP2, a microtubule binding domain, a Ca(2+) binding domain and the conserved residues forming Rab GTPase binding surface were found in the StmTCTP amino acid sequence. For the gene structure, StmTCTP contains four exons separated by three introns. The anti-oxidation and heat shock protein activities of recombinant TCTP protein were also demonstrated in this study. In addition, the expression of StmTCTP was found to be significantly upregulated by polyriboinosinic polyribocytidylic acid [poly (I:C)], lipopolysaccharides (LPS) or inactivated bacteria challenge in in vitro primary culture experiments of coelomocytes, suggested that the sea cucumber TCTP might play critical roles not only in the defense against oxidative and thermal stresses, but also in the innate immune defense against bacterial and viral infections. PMID:25193395

  20. Social sustainability of Mesocyclops biological control for dengue in South Vietnam.

    Science.gov (United States)

    Tran, Thanh Tam; Olsen, Anna; Viennet, Elvina; Sleigh, Adrian

    2015-01-01

    Copepod Mesocyclops as biological control agents for dengue was previously proven to be effective and sustainable in the Northern and Central provinces of Vietnam. We aim to study social sustainability of Mesocyclops intervention in south Vietnam. Both quantitative and qualitative approaches were used. An entomological survey was carried out in 100 random households of Chanh An commune, Vinh Long Province. Aedes larval indices and Mesocyclops prevalence were compared with historical pre- and post-intervention values. In the same commune, using purposeful sampling, sixteen semi-structured interviews (1 villager leader, 1 local doctor, 10 villagers, 2 teachers, 2 entomology officials), and a focus group discussion (6 Mesocyclops program collaborators) explored water storage habits, beliefs about dengue prevention and behaviour related to Mesocyclops. Thematic analysis was conducted to interpret the qualitative findings. Aedes abundance increased after responsibility for Mesocyclops intervention moved from government to community in 2010, with post-transfer surges in Breteau Index, Container Index, and Larval Density Index. Larval increments coincided with decrease in Mesocyclops prevalence. Villagers had some knowledge of dengue but it was conflated with other mosquito borne diseases and understanding of Mesocyclops was incomplete. Program adoption among the villagers was limited. With reduced government support program collaborators reported limited capacity to conduct population monitoring, and instead targeted 'problem' households. Although the Mesocyclops program was highly sustainable in northern and central provinces of Vietnam, the intervention has not been consistently adopted by southern households in Chanh An commune. Limited education, household monitoring and government support are affecting sustainability. Findings were based on a small household sample visited over a short time period, so other evaluations are needed. However, our results suggest that

  1. Engineering and control of biological systems: A new way to tackle complex diseases.

    Science.gov (United States)

    Menolascina, Filippo; Siciliano, Velia; di Bernardo, Diego

    2012-07-16

    The ongoing merge between engineering and biology has contributed to the emerging field of synthetic biology. The defining features of this new discipline are abstraction and standardisation of biological parts, decoupling between parts to prevent undesired cross-talking, and the application of quantitative modelling of synthetic genetic circuits in order to guide their design. Most of the efforts in the field of synthetic biology in the last decade have been devoted to the design and development of functional gene circuits in prokaryotes and unicellular eukaryotes. Researchers have used synthetic biology not only to engineer new functions in the cell, but also to build simpler models of endogenous gene regulatory networks to gain knowledge of the "rules" governing their wiring diagram. However, the need for innovative approaches to study and modify complex signalling and regulatory networks in mammalian cells and multicellular organisms has prompted advances of synthetic biology also in these species, thus contributing to develop innovative ways to tackle human diseases. In this work, we will review the latest progress in synthetic biology and the most significant developments achieved so far, both in unicellular and multicellular organisms, with emphasis on human health. PMID:22580058

  2. Stabilization of labile organic C along a chronosequence of soil development: mineralogical vs. biological controls

    Science.gov (United States)

    McFarland, J. W.; Waldrop, M. P.; Strawn, D.; Harden, J. W.

    2010-12-01

    Soil organic matter (SOM) represents an important reservoir for carbon (C), nitrogen (N), and other essential nutrients. Consequently, variation in SOM turnover rates regulates resource availability for soil microbial activity and plant growth. Long-term SOM stabilization generally involves restricted microbial access to SOM through a variety of processes including complexation with soil minerals. These organo-mineral interactions are influenced by mineral composition and texture, often related to soil age. Soil microorganisms also influence the stabilization of C inputs to the pedosphere through the production of refractory residues controlled in part by C allocation patterns during metabolism. In this study we examined, simultaneously, the contribution of these two C stabilizing mechanisms by ‘tracing’ the fate of two 13C-labeled substrates (glucose and p-hydroxybenzoic acid) along a 1600Kya chronosequence of soil development along the Cowlitz River in southwest Washington. Our objective was to evaluate the relationship between mineralogical and biological controls over C sequestration in soils. Mineralogical analyses were done using the selective dissolutions ammonium oxalate (AOD), and dithionite-citrate extraction (CBD). In this cool, humid environment, intermediate aged soils derived from the late Wisconsin Evans Creek drift (24ka) had the highest AOD extractable Al, Fe, and Si, indicating a higher concentration of poorly crystalline minerals relative to other terraces. Correspondingly, CBD extractable Fe increases with soil age, further supporting the idea that crystalline iron oxides are also more prevalent with weathering. Turnover of both 13C-labeled substrates was rapid (< 12.5 hrs) However, the proportion of substrate mineralized to CO2 varied among terraces. Mineralization to CO2 was significantly lower at 24ka than that for the other three age classes (0.25k, 220k, and 1,600k years bp), corresponding to higher recovery of 13C in bulk soil for this

  3. From biological to lithological control of the B geochemical cycle in a forest watershed (Strengbach, Vosges)

    Science.gov (United States)

    Cividini, D.; Lemarchand, D.; Chabaux, F.; Boutin, R.; Pierret, M.-C.

    2010-06-01

    There is a fast growing interest in understanding the coupling between mineralogical and biological processes responsible for the migration of elements through continental ecosystems. This issue has fundamental impacts at the soil/plant scale because it can explain the tight links between soil and plant development and at the watershed scale because it gives a direct access to the water quality. In the present study, we performed an extended investigation of the bio-geochemical cycle of boron, which is an element known to be suitable for investigating water/rock interactions and vegetation cycling. New B data are provided along the hydro-bio-geochemical continuum in a forest ecosystem (Strengbach basin, Vosges, France), from rainwaters down to the outlet of the basin including systematic analyses of throughfalls, soil solutions, springs and brooks scattered in the watershed. At the watershed scale, we evidence a relationship between the B isotopic composition of river waters and the weathering regime outlining a predominant control of the parent rock mineralogy on the B geochemical behavior. At the soil/plant scale, it appears that the B geochemical cycle is controlled by the vegetation cycling, which is characterized by an uncommon, easy to distinguish, B isotopic composition (δ 11B ranging from about +30‰ to +45‰). Each year the amount of B being involved in the vegetation cycle is about four times greater than that of B being exported out of the watershed. At 10 cm depth in soil, where the plant roots are expected to be the most active, we observe a marked seasonal oscillation of the B isotopic values, which is interpreted as resulting from the vegetation activity. A mass balance calculation based on the assumption that that 10B is preferentially accumulated in the biomass tends to indicate that the soil/plant system does not behave at steady state with respect to B. Because of the very distinct B isotopic signature of vegetation and minerals in soil, box

  4. Control of nitratation in an oxygen-limited autotrophic nitrification/denitrification rotating biological contactor through disc immersion level variation.

    Science.gov (United States)

    Courtens, Emilie N P; Boon, Nico; De Clippeleir, Haydée; Berckmoes, Karla; Mosquera, Mariela; Seuntjens, Dries; Vlaeminck, Siegfried E

    2014-03-01

    With oxygen supply playing a crucial role in an oxygen-limited autotrophic nitrification/denitrification (OLAND) rotating biological contactor (RBC), its controlling factors were investigated in this study. Disc rotation speeds (1.8 and 3.6rpm) showed no influence on the process performance of a lab-scale RBC, although abiotic experiments showed a significant effect on the oxygenation capacity. Estimations of the biological oxygen uptake rate revealed that 85-89% of the oxygen was absorbed by the microorganisms during the air exposure of the discs. Indeed, increasing the disc immersion (50 to 75-80%) could significantly suppress undesired nitratation, on the short and long term. The presented results demonstrated that nitratation could be controlled by the immersion level and revealed that oxygen control in an OLAND RBC should be predominantly based on the atmospheric exposure percentage of the discs.

  5. Successful application of entomopathogenic nematodes for the biological control of western corn rootworm larvae in Europe – a mini review

    Directory of Open Access Journals (Sweden)

    Toepfer, Stefan

    2014-02-01

    Full Text Available 10 years of joint efforts in research and development have led to a nematode-based biological control solution for one of the most destructive maize pests, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae. Commercially mass-produced Heterorhabditis species of beneficial entomopathogenic nematodes are ready to use. They can be applied into the soil during sowing of maize for controlling the subsequently hatching larvae of D. virgifera virgifera thus preventing root feeding and damage to maize. Policy bodies, decision makers and farmers are advised to consider biological control as one of the alternatives to synthetic pesticides in maize production, and according to the EC Directive on the sustainable use of pesticides and implementation of integrated pest management.

  6. Operation and control of SBR processes for enhanced biological nutrient removal from wastewater

    OpenAIRE

    Puig Broch, Sebastià

    2008-01-01

    In the last decades, the awareness of environmental issues has increased in society considerably. There is an increasing need to improve the effluent quality of domestic wastewater treatment processes. This thesis describes the application of the Sequencing Batch Reactor (SBR) technology for Biological Nutrient Removal (BNR) from the wastewater. In particular, the work presented evolves from the nitrogen removal to the biological nutrient removal (i.e. nitrogen plus phosphorous removal) with ...

  7. Compact Electro-Permeabilization System for Controlled Treatment of Biological Cells and Cell Medium Conductivity Change Measurement

    Directory of Open Access Journals (Sweden)

    Novickij Vitalij

    2014-10-01

    Full Text Available Subjection of biological cells to high intensity pulsed electric field results in the permeabilization of the cell membrane. Measurement of the electrical conductivity change allows an analysis of the dynamics of the process, determination of the permeabilization thresholds, and ion efflux influence. In this work a compact electro-permeabilization system for controlled treatment of biological cells is presented. The system is capable of delivering 5 μs - 5 ms repetitive square wave electric field pulses with amplitude up to 1 kV. Evaluation of the cell medium conductivity change is implemented in the setup, allowing indirect measurement of the ion concentration changes occurring due to the cell membrane permeabilization. The simulation model using SPICE and the experimental data of the proposed system are presented in this work. Experimental data with biological cells is also overviewed

  8. A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris.

    Science.gov (United States)

    Dutka, Alexandrea; McNulty, Alison; Williamson, Sally M

    2015-01-01

    There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm(2) soil. Of particular concern is the fact that nematodes from the broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment.

  9. Laboratory evaluation of two native fishes from tropical North Queensland as biological control agents of subterranean Aedes aegypti.

    Science.gov (United States)

    Russell, B M; Wang, J; Williams, Y; Hearnden, M N; Kay, B H

    2001-06-01

    The ability of 2 freshwater fishes, eastern rainbow fish Melanotaenia splendida splendida and fly-specked hardyhead Craterocephalus stercusmuscarum stercusmuscarum, native to North Queensland to prey on immature Aedes aegypti was evaluated under laboratory conditions. The predation efficiency of the 2 species was compared to the exotic guppy, Poecilia reticulata, which is commonly used as a biological control agent of mosquito larvae. Of the 3 fish species tested, M. s. splendida was shown to be the most promising agent for the biological control of Ae. aegypti that breed in wells. Melanotaenia s. splendida consumed significantly greater numbers of immature Ae. aegypti than P. reticulata, irrespective of developmental stage or light conditions. Unlike C s. stercusmuscarum, M. s. splendida could be handled, transported, and kept in captivity for extended periods with negligible mortality. However, M. s. splendida was also an efficient predator of Litoria caerulea tadpoles, a species of native frog found in wells during the dry season. This result may limit the usefulness of M. s. splendida as a biological control agent of well-breeding Ae. aegypti and suggests that predacious copepods, Mesocyclops spp., are more suitable. However, the use of M. s. splendida as a mosquito control agent in containers that are unlikely to support frog populations (e.g., aquaculture tanks and drinking troughs) should be given serious consideration. PMID:11480819

  10. Diagnosis of Physical and Biological Controls on Phytoplankton Distribution in the Sargasso Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Caixia; Paola Malanotte-Rizzoli

    2014-01-01

    The linkage between physical and biological processes is studied by applying a one-dimensional physical-biological coupled model to the Sargasso Sea. The physical model is the Princeton Ocean Model and the biological model is a five-component system including phytoplankton, zooplankton, nitrate, ammonium, and detritus. The coupling between the physical and biological model is accomplished through vertical mixing which is parameterized by the level 2.5 Mellor and Yamada turbulence closure scheme. The coupled model investigates the annual cycle of ecosystem production and the response to external forcing, such as heat flux, wind stress, and surface salinity, and the relative importance of physical processes in affecting the ecosystem. Sensitivity ex-periments are also carried out, which provide information on how the model bio-chemical parameters affect the biological system. The computed seasonal cycles compare reasonably well with the observations of the Bermuda Atlantic Time-series Study (BATS). The spring bloom of phytoplankton occurs in March and April, right after the weakening of the winter mixing and before the estab-lishment of the summer stratification. The bloom of zooplankton occurs about two weeks after the bloom of phytoplankton. The sen-sitivity experiments show that zooplankton is more sensitive to the variations of biochemical parameters than phytoplankton.

  11. Lutte biologique pour l’agriculture et l’environnement américains Biological Control for American Agriculture and the Environment

    Science.gov (United States)

    The European Biological Control Laboratory (EBCL), located on the Agropolis Campus, is operated by the United States Department of Agriculture to conduct research on biological control of invasive arthropods and plants. Many of the target species originated in Europe, Asia or Africa, so we explore ...

  12. Biological control of weeds: research by the United States Department of Agriculture-Agricultural Research Service: selected case studies.

    Science.gov (United States)

    Quimby, Paul C; DeLoach, C Jack; Wineriter, Susan A; Goolsby, John A; Sobhian, Rouhollah; Boyette, C Douglas; Abbas, Hamed K

    2003-01-01

    Research by the USDA-Agricultural Research Service (ARS) on biological control of weeds has been practiced for many years because of its inherent ecological and economic advantages. Today, it is further driven by ARS adherence to Presidential Executive Order 13112 (3 February 1999) on invasive species and to USDA-ARS policy toward developing technology in support of sustainable agriculture with reduced dependence on non-renewable petrochemical resources. This paper reports examples or case studies selected to demonstrate the traditional or classical approach for biological control programs using Old World arthropods against Tamarix spp, Melaleuca quinquenervia (Cav) ST Blake and Galium spurium L/G aparine L, and the augmentative approach with a native plant pathogen against Pueraria lobata Ohwi = P montana. The examples illustrated various conflicts of interest with endangered species and ecological complexities of arthropods with associated microbes such as nematodes.

  13. Cultural and chemical pest control methods alter habitat suitability for biological control agents: An example from Wisconsin commercial cranberry

    Science.gov (United States)

    An integrated pest control program requires an in-depth understanding of the compatibility of all control strategies used. In Wisconsin commercial cranberry production, early-season control strategies may include either a broad-spectrum insecticide application or a corresponding spring flood, along ...

  14. Release and monitoring of Laricobius nigrinus (Coleoptera: Derodontidae) for biological control of the hemlock woolly adelgid in the eastern US

    OpenAIRE

    Mausel, Dave L

    2007-01-01

    Different Laricobius nigrinus Fender release locations, numbers of predators, and timing of release were evaluated for biological control of the hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). It established at 59% of the sites and location was the most important factor related with establishment and abundance, HWA density, and hemlock vigor index. Cold locations had poor establishment or low abundance, declines in HWA density, and increases in hemlock vigor over...

  15. Biological control of aphids in wheat and vegetable crops : a multi-approach case study in Shandong province (China)

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bosquée, Emilie; Chen, Julian; Yong, Liu; Bragard, Claude; Francis, Frédéric

    2014-01-01

    This multi-approach study was conducted in the Shandong province (China) to assess the effectiveness of different biological control methods against aphids in wheat and vegetable crops. Three approaches were tested: (1) wheat/oilseed rape and wheat/pea associations, (2) potatoes/peas association, and (3) E-β-farnesene (aphid alarm pheromone) releasers in squashes under plastic tunnels. Aphids and aphidophagous beneficials were monitored by observations on plants. Wheat associations and E-β-fa...

  16. Effects of chitin and salicylic acid on biological control activity of Pseudomonas spp. against damping off of pepper

    OpenAIRE

    M.Rajkumar; Lee, K. J.; Freitas, H.

    2008-01-01

    Fluorescent pseudomonads (SE21 and RD41) and resistance inducers (chitin and salicylic acid) were examined for plant growth promotion and biological control of damping off of pepper caused by Rhizoctonia solani. The antagonists SE21 and RD41 isolated from the rhizosphere of pepper were found to be effective in inhibiting the mycelial growth of R. solani in a dual culture assay and increasing the seedling vigour in a roll towel assay. Both antagonists were further characterized for biocontrol ...

  17. A Keystone Ant Species Provides Robust Biological Control of the Coffee Berry Borer Under Varying Pest Densities

    OpenAIRE

    Jonathan R Morris; John Vandermeer; Ivette Perfecto

    2015-01-01

    Species' functional traits are an important part of the ecological complexity that determines the provisioning of ecosystem services. In biological pest control, predator response to pest density variation is a dynamic trait that impacts the provision of this service in agroecosystems. When pest populations fluctuate, farmers relying on biocontrol services need to know how natural enemies respond to these changes. Here we test the effect of variation in coffee berry borer (CBB) density on the...

  18. Effects of pollutant accumulation by the invasive weed saltcedar (Tamarix ramosissima) on the biological control agent Diorhabda elongata (Coleoptera: Chrysomelidae)

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Mary A. [Department of Entomology, University of California, Riverside, CA 92521 (United States)], E-mail: mary.sorensen@ucr.edu; Parker, David R. [Department of Environmental Science, University of California, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, CA 92521 (United States)

    2009-02-15

    Hydroponic greenhouse studies were used to investigate the effect of four anthropogenic pollutants (perchlorate (ClO{sub 4}{sup -}), selenium (Se), manganese (Mn), and hexavalent chromium (Cr (VI))) on the biological control agent Diorhabda elongata Brulle. Contaminant concentrations were quantified for experimental Tamarix ramosissima Ledab. plants and D. elongata beetles. Growth of larvae was significantly reduced by Se contamination, but was not affected by the presence of perchlorate, Mn, or Cr (VI). All of the contaminants were transferred from plants to D. elongata beetles. Only Cr (VI) was accumulated at greater levels in beetles than in their food. Because T. ramosissima grows in disturbed areas, acquires salts readily, and utilizes groundwater, this plant is likely to accumulate anthropogenic pollutants in contaminated areas. This study is one of the first to investigate the potential of an anthropogenic pollutant to influence a weed biological control system. - The presence of Se, but not perchlorate, Mn, or Cr (VI), in foliage of the invasive weed saltcedar was shown to reduce growth of the biological control agent Diorhabda elongata.

  19. Innate positive chemotaxis to pollen from crops and banker plants in predaceous biological control agents: towards new field lures?

    Science.gov (United States)

    Li, Shu; Tan, Xiaoling; Desneux, Nicolas; Benelli, Giovanni; Zhao, Jing; Li, Xinhai; Zhang, Fan; Gao, Xiwu; Wang, Su

    2015-01-01

    Predator-prey interactions form the core of biological control of arthropod pests. Which tools can be used to monitor and collect carnivorous arthropods in natural habitats and targeted crops? Eco-friendly and effective field lures are urgently needed. In this research, we carried out olfactometer experiments assess innate positive chemotaxis to pollen of seven crop and banker plant by two important predatory biological control agents: the coccinellid Propylea japonica (Thunberg) and the anthocorid Orius sauteri (Poppius). We compared the attractiveness of pollens from crops and banker plants to that of common prey homogenates (aphids and thrips, respectively). Attractiveness of the tested odor sources was checked via field trapping experiments conducted in organic apple orchards and by release-recapture assays in organic greenhouse tomato crops. Maize and canola pollen were attractive to both P. japonica and O. sauteri, in laboratory and field assays. P. japonica was highly attracted by balm mint pollen, whereas O. sauteri was attracted by alfalfa pollen. Our results encourage the use of pollen from crops and banker plants as low-cost and eco-friendly attractors to enhance the monitoring and attraction of arthropod predators in biological control programs. PMID:26235136

  20. Risk assessment and stakeholder perceptions in novel biological control agent release: YST as a case study

    Science.gov (United States)

    The objectives of risk assessment are to learn about whether a candidate agent would be safe to use in the environment where release is planned, and to present such information in a clear, understandable format to regulators, stakeholders, and the public. Plant pathogens evaluated for biological co...

  1. Genetic control of chromosome behaviour: Implications in evolution, crop improvement, and human biology

    Science.gov (United States)

    Chromosomes and chromosome pairing are pivotal to all biological sciences. The study of chromosomes helps unravel several aspects of an organism. Although the foundation of genetics occurred with the formulation of the laws of heredity in 1865, long before the discovery of chromosomes, their subsequ...

  2. The effect of biological and chemical control agents on the health status of the very early potato cultivar Rosara

    Directory of Open Access Journals (Sweden)

    Cwalina-Ambroziak Bożena

    2015-12-01

    Full Text Available The external appearance and quality of table potatoes are determined, among other factors, by the health status of the plants during the growing season. Chemical control methods are often combined with biocontrol agents to effectively fight potato pathogens. Potatoes of the very early cultivar Rosara were grown in experimental plots. The plots were located in Tomaszkowo (NE Poland, 2007-2009. The experiment involved the following treatments: 1 biological control − mycorrhizal Glomus spp. inoculum was applied to the roots, − tubers were dressed and plants were sprayed with Polyversum three times during the growing season, 2 chemical control - at two-week intervals, plants were sprayed with the following fungicides: Infinito 687.5 SC and Tanos 50 WG, Valbon 72 WG and Tanos 50 WG. In the control treatment, potato plants were not protected against pathogens. During the growing season, the severity of late blight and early blight was evaluated on a nine-point scale. The composition of fungal communities colonising potato stems was analysed. The fungistatic properties of the fungicides used in the field experiment were evaluated in an in vitro test. The symptoms of infections caused by Phytophthora infestans and Alternaria spp. were significantly reduced in the treatment which used the integrated chemical and biological control. The least diverse fungal community was isolated from fungicide-treated plants. In the in vitro test, fungicides at all analysed concentrations inhibited the linear mycelial growth of selected pathogens.

  3. Control of biological growth in recirculating cooling systems using treated secondary effluent as makeup water with monochloramine.

    Science.gov (United States)

    Chien, Shih-Hsiang; Chowdhury, Indranil; Hsieh, Ming-Kai; Li, Heng; Dzombak, David A; Vidic, Radisav D

    2012-12-01

    Secondary-treated municipal wastewater, an abundant and widely distributed impaired water source, is a promising alternative water source for thermoelectric power plant cooling. However, excessive biological growth is a major challenge associated with wastewater reuse in cooling systems as it can interfere with normal system operation as well as enhance corrosion and scaling problems. Furthermore, possible emission of biological aerosols (e.g., Legionella pneumophila) with the cooling tower drift can lead to public health concerns within the zone of aerosol deposition. In this study, the effectiveness of pre-formed and in-situ-formed monochloramine was evaluated for its ability to control biological growth in recirculating cooling systems using secondary-treated municipal wastewater as the only makeup water source. Bench-scale studies were compared with pilot-scale studies for their ability to predict system behavior under realistic process conditions. Effectiveness of the continuous addition of pre-formed monochloramine and monochloramine formed in-situ through the reaction of free chlorine with ammonia in the incoming water was evaluated in terms of biocide residual and its ability to control both planktonic and sessile microbial populations. Results revealed that monochloramine can effectively control biofouling in cooling systems employing secondary-treated municipal wastewater and has advantages relative to use of free chlorine, but that bench-scale studies seriously underestimate biocide dose and residual requirements for proper control of biological growth in full-scale systems. Pre-formed monochloramine offered longer residence time and more reliable performance than in-situ-formed monochloramine due to highly variable ammonia concentration in the recirculating water caused by ammonia stripping in the cooling tower. Pilot-scale tests revealed that much lower dosing rate was required to maintain similar total chlorine residual when pre-formed monochloramine

  4. Maize benefits the predatory beetle, Propylea japonica (Thunberg, to provide potential to enhance biological control for aphids in cotton.

    Directory of Open Access Journals (Sweden)

    Fang Ouyang

    Full Text Available BACKGROUND: Biological control provided by natural enemies play an important role in integrated pest management. Generalist insect predators provide an important biological service in the regulation of agricultural insect pests. Our goal is to understand the explicit process of oviposition preference, habitat selection and feeding behavior of predators in farmland ecosystem consisting of multiple crops, which is central to devising and delivering an integrated pest management program. METHODOLOGY: The hypotheses was that maize can serve as habitat for natural enemies and benefits predators to provide potential to enhance biological control for pest insects in cotton. This explicit process of a predatory beetle, Propylea japonica, in agricultural ecosystem composed of cotton and maize were examined by field investigation and stable carbon isotope analysis during 2008-2010. PRINCIPAL FINDING: Field investigation showed that P. japonica adults will search host plants for high prey abundance before laying eggs, indicating indirectly that P. japonica adults prefer to inhabit maize plants and travel to cotton plants to actively prey on aphids. The δ(13C values of adult P. japonica in a dietary shift experiment found that individual beetles were shifting from a C(3- to a C(4-based diet of aphids reared on maize or cotton, respectively, and began to reflect the isotope ratio of their new C(4 resources within one week. Approximately 80-100% of the diet of P. japonica adults in maize originated from a C(3-based resource in June, July and August, while approximately 80% of the diet originated from a C(4-based resource in September. CONCLUSION/SIGNIFICANCE: Results suggest that maize can serve as a habitat or refuge source for the predatory beetle, P. japonica, and benefits predators to provide potential to enhance biological control for insect pests in cotton.

  5. Biologically Plausible Control of Fast Reaching Movements Using Non-Traditional Cost Functions

    OpenAIRE

    Gamble, Geoffrey

    2016-01-01

    Optimal control has been used as a technique to uncover mathematical principles which are observed regularly in the dynamics of human movement. We present two new models of human reaching movements. While both are rooted in optimal control theory, the models were conceived by questioning basic tenets and typical practices used in optimal control as applied to human movement. In the first model, we use cost functions that measure various control signals via the L_infinity norm as opposed to th...

  6. Chemical and biological control of silvery threadmoss on creeping bentgrass putting greens

    OpenAIRE

    Post, Angela R

    2013-01-01

    Silvery threadmoss is a problematic weed of golf putting greens, growing interspersed with turf, decreasing aesthetic quality and playability.  Moss is typically controlled postemergence and currently only one herbicide, carfentrazone, is registered for silvery threadmoss control on greens.  Carfentrazone controls moss up to 75% applied at a three week interval throughout the growing season.  Alternatives providing longer residual or more effective control are desirable.  Studies were conduct...

  7. Evidence for 2D Solitary Sound Waves in a Lipid Controlled Interface and its Biological Implications

    CERN Document Server

    Shrivastava, Shamit

    2014-01-01

    Biological membranes by virtue of their elastic properties should be capable of propagating localized perturbations analogous to sound waves. However, the existence and the possible role of such waves in communication in biology remains unexplored. Here we report the first observations of 2D solitary elastic pulses in lipid interfaces, excited mechanically and detected by FRET. We demonstrate that the nonlinearity near a maximum in the susceptibility of the lipid monolayer results in solitary pulses that also have a threshold for excitation. These experiments clearly demonstrate that the state of the interface regulates the propagation of pulses both qualitatively and quantitatively. We elaborate on the striking similarity of the observed phenomenon to nerve pulse propagation and a thermodynamic basis of cell signaling in general.

  8. The use of mulch to increase Spider (Arachnidae) numbers; a habitat approach to biological insect control

    OpenAIRE

    Manns, Mrs. Hida R.; Murray, D L; Beresford, D. V.

    2008-01-01

    The potential for insect predators to contribute to a biological balance of insect species was explored with mulch. Insects were collected in pitfall traps in outdoor microplots over 3 seasons in southern Ontario, Canada. Treatments varied each season with crops of oats or soybeans, with residue of straw, corn stalks or paperfibre, and with residue tilled in or surface applied. In 2006 at the peak of spider population density there was a significant effect of the plant and the paperfibre r...

  9. Efficacy of biological insecticides to control the Colorado potato beetle (Leptinotasara decemlineata) in organic farming

    OpenAIRE

    Kühne, Stefan; Reelfs, Torben; Ellmer, Frank; Moll, Eckard; Kleinhenz, Benno; Gemmer, Christine

    2008-01-01

    The Colorado potato beetle (Leptinotasara decemlineata Say) is one of the most important pests on potatoes (Solanum tuberosum). In the present study, we compared the efficacy of three biological insecticides – Neem (NeemAzal-T/S), pyrethrum/rapeseed oil (Spruzit Neu) and Bacillus thuringiensis var. tenebrionis (Novodor FC) – against this pest in field trials conducted from 2005 to 2007. The combined and temporarily shifted application of neem and B.t.t. reduced significantly the number of bee...

  10. Utility of the molecular biology techniques to the analytical control of the microbiological quality of waters

    International Nuclear Information System (INIS)

    The molecular biology techniques made accessible to the water industry the ability to detect and quantify, in a few hours, any organism known. given this scenario, it is important to realize the strengths and weaknesses of these techniques to get a better picture of the scope of its implementation and its most that probably usefulness. We must be familiar with these techniques to understand the results and properly evaluate its detection limit. (Author) 4 refs.

  11. What controls biological productivity in coastal upwelling systems? Insights from a comparative modeling study

    Directory of Open Access Journals (Sweden)

    Z. Lachkar

    2011-06-01

    Full Text Available The magnitude of the biological productivity in Eastern Boundary Upwelling Systems (EBUS is traditionally viewed as directly reflecting the upwelling intensity. Yet, different EBUS show different sensitivities of productivity to upwelling-favorable winds (Carr and Kearns, 2003. Here, using a comparative modeling study of the California Current System (California CS and Canary Current System (Canary CS, we show how physical and environmental factors, such as light, temperature and cross-shore circulation modulate the response of biological productivity to upwelling strength. To this end, we made a series of eddy-resolving simulations of the California CS and Canary CS using the Regional Ocean Modeling System (ROMS, coupled to a nitrogen based Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD ecosystem model. We find the nutrient content of the euphotic zone to be 20 % smaller in the Canary CS relative to the California CS. Yet, the biological productivity is 50 % smaller in the latter. This is due to: (1 a faster nutrient-replete growth in the Canary CS relative to the California CS, related to a more favorable light and temperature conditions in the Canary CS, and (2 the longer nearshore water residence times in the Canary CS which lead to larger buildup of biomass in the upwelling zone, thereby enhancing the productivity. The longer residence times in the Canary CS appear to be associated with the wider continental shelves and the lower eddy activity characterizing this upwelling system. This results in a weaker offshore export of nutrients and organic matter, thereby increasing local nutrient recycling and enhancing the coupling between new and export production in the Northwest African system. Our results suggest that climate change induced perturbations such as upwelling favorable wind intensification might lead to contrasting biological responses in the California CS and the Canary CS, with major implications for the biogeochemical cycles

  12. What controls biological productivity in coastal upwelling systems? Insights from a comparative modeling study

    OpenAIRE

    Z. Lachkar; Gruber, N.

    2011-01-01

    The magnitude of the biological productivity in Eastern Boundary Upwelling Systems (EBUS) is traditionally viewed as directly reflecting the upwelling intensity. Yet, different EBUS show different sensitivities of productivity to upwelling-favorable winds (Carr and Kearns, 2003). Here, using a comparative modeling study of the California Current System (California CS) and Canary Current System (Canary CS), we show how physical and environmental factors, such as light, temperature and c...

  13. Ecological Complexity in a Coffee Agroecosystem: Spatial Heterogeneity, Population Persistence and Biological Control

    OpenAIRE

    Heidi Liere; Doug Jackson; John Vandermeer

    2012-01-01

    BACKGROUND: Spatial heterogeneity is essential for the persistence of many inherently unstable systems such as predator-prey and parasitoid-host interactions. Since biological interactions themselves can create heterogeneity in space, the heterogeneity necessary for the persistence of an unstable system could be the result of local interactions involving elements of the unstable system itself. METHODOLOGY/PRINCIPAL FINDINGS: Here we report on a predatory ladybird beetle whose natural history ...

  14. Mixed cropping systems for biological control of weeds and pests in organic oilseed crops

    OpenAIRE

    Paulsen, Hans Marten; Schochow, Martin; Ulber, B; Kühne, Stefan; Rahmann, Gerold

    2006-01-01

    Agricultural advantages of mixed cropping are gained by biological effects like light competition, offering weed-suppressing capacities or by diversification of plant covers to break development cycles of pests. In a two-year project on mixed cropping with organic oilseed crops these effects were measured. It was found that weeds can be efficiently suppressed in organic linseed (Linum usitatissivum) in crop combinations with wheat (Triticum aestivum) or false flax (Camelina sativa). But linse...

  15. Biological and physical controls in the Southern Ocean on past millennial-scale atmospheric CO2 changes

    Science.gov (United States)

    Gottschalk, Julia; Skinner, Luke C.; Lippold, Jörg; Vogel, Hendrik; Frank, Norbert; Jaccard, Samuel L.; Waelbroeck, Claire

    2016-05-01

    Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a 'control valve' on ocean-atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air-sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and 14C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the biological export of carbon and increases in deep-ocean ventilation via southern-sourced water masses. These findings demonstrate how the Southern Ocean's 'organic carbon pump' has exerted a tight control on atmospheric CO2, and thus global climate, specifically via a synergy of both physical and biological processes.

  16. Low doses of ionizing radiation: Biological effects and regulatory control. Invited papers and discussions. Proceedings of an international conference

    International Nuclear Information System (INIS)

    The levels and biological effects resulting from exposure to ionizing radiation are continuously reviewed by the United Nations Committee on the Effects of Atomic Radiation (UNSCEAR). Since its creation in 1928, the International Commission on Radiological Protection (ICRP) has issued recommendations on protection against ionizing radiation. The UNSCEAR estimates and the ICRP recommendations have served as the basis for national and international safety standards on radiation safety, including those developed by the International Atomic Energy Agency (IAEA) and the World Health Organization (WHO). Concerning health effects of low doses of ionizing radiation, the international standards are based on the plausible assumption that, above the unavoidable background radiation dose, the probability of effects increases linearly with dose, i.e. on a 'linear, no threshold' (LNT) assumption. However, in recent years the biological estimates of health effects of low doses of ionizing radiation and the regulatory approach to the control of low level radiation exposure have been much debated. To foster information exchange on the relevant issues, an International Conference on Low Doses of Ionizing Radiation: Biological Effects and Regulatory Control, jointly sponsored by the IAEA and WHO in co-operation with UNSCEAR, was held from 17-21 November 1997 at Seville, Spain. These Proceedings contain the invited special reports, keynote papers, summaries of discussions, session summaries and addresses presented at the opening and closing of the Conference

  17. Construction of new synthetic biology tools for the control of gene expression in the cyanobacterium Synechococcus sp. strain PCC 7002.

    Science.gov (United States)

    Zess, Erin K; Begemann, Matthew B; Pfleger, Brian F

    2016-02-01

    Predictive control of gene expression is an essential tool for developing synthetic biological systems. The current toolbox for controlling gene expression in cyanobacteria is a barrier to more in-depth genetic analysis and manipulation. Towards relieving this bottleneck, this work describes the use of synthetic biology to construct an anhydrotetracycline-based induction system and adapt a trans-acting small RNA (sRNA) system for use in the cyanobacterium Synechococcus sp. strain PCC 7002. An anhydrotetracycline-inducible promoter was developed to maximize intrinsic strength and dynamic range. The resulting construct, PEZtet , exhibited tight repression and a maximum 32-fold induction upon addition of anhydrotetracycline. Additionally, a sRNA system based on the Escherichia coli IS10 RNA-IN/OUT regulator was adapted for use in Synechococcus sp. strain PCC 7002. This system exhibited 70% attenuation of target gene expression, providing a demonstration of the use of sRNAs for differential gene expression in cyanobacteria. These systems were combined to produce an inducible sRNA system, which demonstrated 59% attenuation of target gene expression. Lastly, the role of Hfq, a critical component of sRNA systems in E. coli, was investigated. Genetic studies showed that the Hfq homolog in Synechococcus sp. strain PCC 7002 did not impact repression by the engineered sRNA system. In summary, this work describes new synthetic biology tools that can be applied to physiological studies, metabolic engineering, or sRNA platforms in Synechococcus sp. strain PCC 7002.

  18. Biological and physical controls in the Southern Ocean on past millennial-scale atmospheric CO2 changes.

    Science.gov (United States)

    Gottschalk, Julia; Skinner, Luke C; Lippold, Jörg; Vogel, Hendrik; Frank, Norbert; Jaccard, Samuel L; Waelbroeck, Claire

    2016-01-01

    Millennial-scale climate changes during the last glacial period and deglaciation were accompanied by rapid changes in atmospheric CO2 that remain unexplained. While the role of the Southern Ocean as a 'control valve' on ocean-atmosphere CO2 exchange has been emphasized, the exact nature of this role, in particular the relative contributions of physical (for example, ocean dynamics and air-sea gas exchange) versus biological processes (for example, export productivity), remains poorly constrained. Here we combine reconstructions of bottom-water [O2], export production and (14)C ventilation ages in the sub-Antarctic Atlantic, and show that atmospheric CO2 pulses during the last glacial- and deglacial periods were consistently accompanied by decreases in the biological export of carbon and increases in deep-ocean ventilation via southern-sourced water masses. These findings demonstrate how the Southern Ocean's 'organic carbon pump' has exerted a tight control on atmospheric CO2, and thus global climate, specifically via a synergy of both physical and biological processes. PMID:27187527

  19. Controls of biological soil crust cover and composition shift with succession in sagebrush shrub-steppe

    Science.gov (United States)

    Dettweiler-Robinson, E.; Bakker, J.D.; Grace, J.B.

    2013-01-01

    Successional stage may determine strength and causal direction of interactions among abiotic and biotic factors; e.g., species that facilitate the establishment of other species may later compete with them. We evaluated multivariate hypotheses about abiotic and biotic factors shaping biological soil crusts (BSCs) in early and late successional stages. We surveyed vegetation and BSC in the shrub-steppe ecosystem of the Columbia Basin. We analyzed the relationships with bryophyte and lichen covers using structural equation models, and analyzed the relationships with BSC composition using Indicator Species Analysis and distance-based linear models. Cover, indicator species, and composition varied with successional stage. Increasing elevation and bryophyte cover had higher lichen cover early in succession; these relationships were negative in the later successional stage. Lichen cover did not appear to impede B. tectorum cover, but B. tectorum appeared to strongly negatively affect lichen cover in both stages. Biological soil crust composition varied with bunchgrass cover in the early successional stage, but with elevation and B. tectorum cover later in succession. Our findings support the hypotheses that as succession progresses, the strength and direction of certain community interactions shift, and B. tectorum leads to reductions in biological soil crust cover regardless of successional stage.

  20. Differential Inactivation of Seed Exudate Stimulation of Pythium ultimum Sporangium Germination by Enterobacter cloacae Influences Biological Control Efficacy on Different Plant Species

    OpenAIRE

    Kageyama, Koji; Nelson, Eric B.

    2003-01-01

    This study was initiated to understand whether differential biological control efficacy of Enterobacter cloacae on various plant species is due to differences in the ability of E. cloacae to inactivate the stimulatory activity of seed exudates to Pythium ultimum sporangium germination. In biological control assays, E. cloacae was effective in controlling Pythium damping-off when placed on the seeds of carrot, cotton, cucumber, lettuce, radish, tomato, and wheat but failed to protect corn and ...

  1. Reducing losses inflicted by insect pests on cashew, using weaver ants as a biological control agent

    DEFF Research Database (Denmark)

    Anato, Florence; Wargui, Rosine; Sinzogan, Antonio;

    2015-01-01

    BACKGROUND: Cashew (Anacardium occidentale Linnaeus) is the largest agricultural export product in Benin. However, yields and quality are lost due to inefficient pest control. Weaver ants (Oecophylla spp.) may control pests in this crop as they eat and deter pests. In Benin, cashew pest damages......, nut quality and yield were compared among: (i) trees with weaver ant (Oecophylla longinoda Latreille), (ii) trees where weaver ants were fed sugar, (iii) IPM trees with weaver ants combined with GF-120 (a natural insecticide), and (iv) control trees receiving no control measures. RESULTS: Thrips...... damages on nuts were higher than other damage symptoms and significantly lower on control trees compared to other treatments. Percentage of first quality nuts was higher in the control compared to ants treatments, but not different from the IPM-treatment. However, compared to the control treatment, ants...

  2. Biological Control of the Invasive Dryocosmus kuriphilus (Hymenoptera: Cynipidae - an Overview and the First Trials in Croatia

    Directory of Open Access Journals (Sweden)

    Dinka Matošević

    2014-06-01

    Full Text Available Background and Purpose: Dryocosmus kuriphilus is a globally invasive insect pest, spreading very quickly in new habitats and making serious damage to sweet chestnut forests in Croatia and in several other European countries. Indigenous parasitoid species trophically associated with oak gallwasps have adapted to this new host but cannot effectively regulate its population density. Classical biological control using parasitoid Torymus sinensis has been proven to be the only effective method of controlling the populations of D. kuriphilus and has been successfully applied in Japan, South Korea, the USA and Italy. The aim of this review paper is to provide overview and up-to date knowledge about biological control of D. kurphilus and to describe first steps of introduction of T. sinensis to sweet chestnut forests in Croatia. Conclusions and Future Prospects: Results presented in this paper show adapted biology and behavioural traits of T. sinensis to its host D. kuriphilus. The history and results of introductions of T. sinensis to Japan, the USA, Italy, France and Hungary are shown. The first report of release of T. sinensis to sweet chestnut forests in Croatia is given with discussion on native parasitoids attacking D. kuriphilus. Possible negative effects of T. sinensis on native parasitoid fauna and risks that could influence the successful establishment of T. sinensis in Croatia are discussed. Previous experiences have shown that T. sinensis can successfully control the population density of D. kuriphilus, slowing down the spread and mitigating negative impact of this invasive chestnut pest and keeping the damage of D. kuriphilus at acceptable level. High specificity of T. sinensis suggests that it has limited potential of exploiting native hosts but further detailed monitoring of native parasitoid and possible interactions with introduced T. sinensis is strongly suggested.

  3. A new era in brown adipose tissue biology: molecular control of brown fat development and energy homeostasis.

    Science.gov (United States)

    Kajimura, Shingo; Saito, Masayuki

    2014-01-01

    Brown adipose tissue (BAT) is specialized to dissipate chemical energy in the form of heat as a defense against cold and excessive feeding. Interest in the field of BAT biology has exploded in the past few years because of the therapeutic potential of BAT to counteract obesity and obesity-related diseases, including insulin resistance. Much progress has been made, particularly in the areas of BAT physiology in adult humans, developmental lineages of brown adipose cell fate, and hormonal control of BAT thermogenesis. As we enter into a new era of brown fat biology, the next challenge will be to develop strategies for activating BAT thermogenesis in adult humans to increase whole-body energy expenditure. This article reviews the recent major advances in this field and discusses emerging questions. PMID:24188710

  4. A biomimetic DNA-based channel for the ligand-controlled transport of charged molecular cargo across a biological membrane

    Science.gov (United States)

    Burns, Jonathan R.; Seifert, Astrid; Fertig, Niels; Howorka, Stefan

    2016-02-01

    Biological ion channels are molecular gatekeepers that control transport across cell membranes. Recreating the functional principle of such systems and extending it beyond physiological ionic cargo is both scientifically exciting and technologically relevant to sensing or drug release. However, fabricating synthetic channels with a predictable structure remains a significant challenge. Here, we use DNA as a building material to create an atomistically determined molecular valve that can control when and which cargo is transported across a bilayer. The valve, which is made from seven concatenated DNA strands, can bind a specific ligand and, in response, undergo a nanomechanical change to open up the membrane-spanning channel. It is also able to distinguish with high selectivity the transport of small organic molecules that differ by the presence of a positively or negatively charged group. The DNA device could be used for controlled drug release and the building of synthetic cell-like or logic ionic networks.

  5. A biologically inspired modular structure to control the sit-to-stand transfer of a biped robot.

    Science.gov (United States)

    Andani, M Emadi; Bahrami, F; Maralani, P Jabedar

    2007-01-01

    In this study, a biologically inspired control structure to control the sit-to-stand (STS) transfer from a chair is developed and simulated. STS movement is consisted of two main phases. First phase of the movement is before leaving the seat (seat-off moment). In this phase seat reactions forces act on the body parts which are in contact with the seat. The second phase is after seat-off, where the only external forces acting on the body are ground reaction forces. A proper control algorithm of the STS transfer needs to consider switching between these two phases, which correspond to two different dynamical structures. The control structure developed and discussed in this work is based on the MOSAIC structure, proposed first by Wolpert and Kawato [1]. Original MOSAIC structure has a modular architecture which is based on multiple pairs of forward and inverse models of the dynamical system to be controlled, and each module is trained separately to learn one part of a given task. The number of effective modules is predetermined. We have developed a new method to train all modules simultaneously. This method is based on reinforcement and cooperative competitive learning, and the number of effective modules is determined automatically. In this study, the simulation was begun with four modules. Our results showed that only two modules out of four were selected to control the STS task. Responsibility of controlling the task was switched between the two modules around the seat-off moment.

  6. 75 FR 69396 - Availability of an Environmental Assessment for a Biological Control Agent for Arundo donax

    Science.gov (United States)

    2010-11-12

    ... the control of Arundo donax (giant reed, Carrizo cane). The environmental assessment considers the..., prescribed fires, biomass removal, and other methods. However, these management measures are...

  7. The plumbing of the global biological pump: Efficiency control through leaks, pathways, and time scales

    Science.gov (United States)

    Pasquier, Benoît; Holzer, Mark

    2016-08-01

    We systematically quantify the pathways and time scales that set the efficiency, Ebio, of the global biological pump by applying Green-function-based diagnostics to a data-assimilated phosphorus cycle embedded in a jointly assimilated ocean circulation. We consider "bio pipes" that consist of phosphorus paths that connect specified regions of last biological utilization with regions where regenerated phosphate first reemerges into the euphotic zone. The bio pipes that contribute most to Ebio connect the Eastern Equatorial Pacific (EEqP) and Equatorial Atlantic to the Southern Ocean ((21 ± 3)% of Ebio), as well as the Southern Ocean to itself ((15 ± 3)% of Ebio). The bio pipes with the largest phosphorus flow rates connect the EEqP to itself and the subantarctic Southern Ocean to itself. The global mean sequestration time of the biological pump is 130 ± 70 years, while the sequestration time of the bio pipe from anywhere to the Antarctic region of the Southern Ocean is 430 ± 30 years. The distribution of phosphorus flowing within a given bio pipe is quantified by its transit-time partitioned path density. For the largest bio pipes, ˜1/7 of their phosphorus is carried by thermocline paths with transit times less than ˜300-400 years, while ˜4/7 of their phosphorus is carried by abyssal paths with transit times exceeding ˜700 years. The path density reveals that Antarctic Intermediate Water carries about a third of the regenerated phosphate last utilized in the EEqP that is destined for the Southern Ocean euphotic zone. The Southern Ocean is where (62 ± 2)% of the regenerated inventory and (69 ± 1)% of the preformed inventory first reemerge into the euphotic zone.

  8. Movement duration, Fitts's law, and an infinite-horizon optimal feedback control model for biological motor systems.

    Science.gov (United States)

    Qian, Ning; Jiang, Yu; Jiang, Zhong-Ping; Mazzoni, Pietro

    2013-03-01

    Optimization models explain many aspects of biological goal-directed movements. However, most such models use a finite-horizon formulation, which requires a prefixed movement duration to define a cost function and solve the optimization problem. To predict movement duration, these models have to be run multiple times with different prefixed durations until an appropriate duration is found by trial and error. The constrained minimum time model directly predicts movement duration; however, it does not consider sensory feedback and is thus applicable only to open-loop movements. To address these problems, we analyzed and simulated an infinite-horizon optimal feedback control model, with linear plants, that contains both control-dependent and control-independent noise and optimizes steady-state accuracy and energetic costs per unit time. The model applies the steady-state estimator and controller continuously to guide an effector to, and keep it at, target position. As such, it integrates movement control and posture maintenance without artificially dividing them with a precise, prefixed time boundary. Movement pace is determined by the model parameters, and the duration is an emergent property with trial-to-trial variability. By considering the mean duration, we derived both the log and power forms of Fitts's law as different approximations of the model. Moreover, the model reproduces typically observed velocity profiles and occasional transient overshoots. For unbiased sensory feedback, the effector reaches the target without bias, in contrast to finite-horizon models that systematically undershoot target when energetic cost is considered. Finally, the model does not involve backward and forward sweeps in time, its stability is easily checked, and the same solution applies to movements of different initial conditions and distances. We argue that biological systems could use steady-state solutions as default control mechanisms and might seek additional optimization of

  9. Tuning of nanoparticle biological functionality through controlled surface chemistry and characterisation at the bioconjugated nanoparticle surface

    Science.gov (United States)

    Hristov, Delyan R.; Rocks, Louise; Kelly, Philip M.; Thomas, Steffi S.; Pitek, Andrzej S.; Verderio, Paolo; Mahon, Eugene; Dawson, Kenneth A.

    2015-12-01

    We have used a silica - PEG based bionanoconjugate synthetic scheme to study the subtle connection between cell receptor specific recognition and architecture of surface functionalization chemistry. Extensive physicochemical characterization of the grafted architecture is capable of capturing significant levels of detail of both the linker and grafted organization, allowing for improved reproducibility and ultimately insight into biological functionality. Our data suggest that scaffold details, propagating PEG layer architecture effects, determine not only the rate of uptake of conjugated nanoparticles into cells but also, more significantly, the specificity of pathways via which uptake occurs.

  10. Mosquito vector biology and control in Latin America - a 24th symposium

    Science.gov (United States)

    The 24th Annual Latin American Symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 80th Annual Meeting in Seattle, WA in February 2014. The principal objective, as for the previous 23 symposia, was to promote participation in the AMCA by vector control spe...

  11. Mosquito vector biology and control in Latin America - A 25th Symposium

    Science.gov (United States)

    The 25th Annual Latin American Symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 81st Annual Meeting in New Orleans, LA, in March 2015. The principal objective, for the previous 24 symposia, was to promote participation in the AMCA by vector control spec...

  12. Mosquito vector biology and control in Latin America - a 22nd Symposium

    Science.gov (United States)

    The 22nd Annual Latin American Symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 78th Annual Meeting in Austin, TX in February 2012. The principal objective, as for the previous 21 symposia, was to promote participation in the AMCA by vector control spec...

  13. Control of a Biological Nitrogen Removal Process in an Intensified Single Reactor Configuration

    DEFF Research Database (Denmark)

    Vangsgaard, Anna Katrine; Mauricio Iglesias, Miguel; Gernaey, Krist;

    2013-01-01

    The nitrogen removing granular sludge process is a novel and intensified process. However, its stable operation and control remains a challenging problem. In this contribution, a new process oriented approach is used to develop, evaluate and benchmark control strategies to ensure stable operation...

  14. 76 FR 3076 - Availability of an Environmental Assessment for a Biological Control Agent for Air Potato

    Science.gov (United States)

    2011-01-19

    ... Control Agent for Air Potato AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Notice of... Inspection Service has prepared an environmental assessment (EA) relative to the control of air potato... severity of air potato infestations. We are making the EA available to the public for review and...

  15. Correlation of Arsenic Levels in Smokeless Tobacco Products and Biological Samples of Oral Cancer Patients and Control Consumers.

    Science.gov (United States)

    Arain, Sadaf S; Kazi, Tasneem G; Afridi, Hassan I; Talpur, Farah N; Kazi, Atif G; Brahman, Kapil D; Naeemullah; Panhwar, Abdul H; Kamboh, Muhammad A

    2015-12-01

    It has been extensively reported that chewing of smokeless tobacco (SLT) can lead to cancers of oral cavity. In present study, the relationship between arsenic (As) exposure via chewing/inhaling different SLT products in oral cancer patients have or/not consumed SLT products was studied. The As in different types of SLT products (gutkha, mainpuri, and snuff) and biological (scalp hair and blood) samples of different types of oral cancer patients and controls were analyzed. Both controls and oral cancer patients have same age group (ranged 30-60 years), socio-economic status, localities, and dietary habits. The concentrations of As in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data of present study indicates that the concentration of As was significantly higher in scalp hair and blood samples of oral cancer patients than those of controls (p0.01). The intake of As via consuming different SLT may have synergistic effects, in addition to other risk factors associated with oral cancer.

  16. Correlation of Arsenic Levels in Smokeless Tobacco Products and Biological Samples of Oral Cancer Patients and Control Consumers.

    Science.gov (United States)

    Arain, Sadaf S; Kazi, Tasneem G; Afridi, Hassan I; Talpur, Farah N; Kazi, Atif G; Brahman, Kapil D; Naeemullah; Panhwar, Abdul H; Kamboh, Muhammad A

    2015-12-01

    It has been extensively reported that chewing of smokeless tobacco (SLT) can lead to cancers of oral cavity. In present study, the relationship between arsenic (As) exposure via chewing/inhaling different SLT products in oral cancer patients have or/not consumed SLT products was studied. The As in different types of SLT products (gutkha, mainpuri, and snuff) and biological (scalp hair and blood) samples of different types of oral cancer patients and controls were analyzed. Both controls and oral cancer patients have same age group (ranged 30-60 years), socio-economic status, localities, and dietary habits. The concentrations of As in SLT products and biological samples were measured by electrothermal atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data of present study indicates that the concentration of As was significantly higher in scalp hair and blood samples of oral cancer patients than those of controls (p0.01). The intake of As via consuming different SLT may have synergistic effects, in addition to other risk factors associated with oral cancer. PMID:25975948

  17. Postharvest biological control of brown rot in peaches after cold storage preceded by preharvest chemical control 1

    Directory of Open Access Journals (Sweden)

    Elizandra Pivotto Pavanello

    2015-12-01

    Full Text Available ABSTRACT Pathogenic fungi cause skin darkening and peach quality depreciation in post harvest. Therefore, alternative techniques to chemical treatment are necessary in order to reduce risks to human health. The aim of this study was to evaluate the effect of the application of Trichoderma harzianum in association with different fungicides applied before harvest to 'Eldorado' peaches for brown rot control and other quality parameters during storage. The treatments consisted of five preharvest fungicide applications (control, captan, iprodione, iminoctadine and tebuconazole associated with postharvest application of T. harzianum, after cold storage (with and without application, in three evaluation times (zero, two and four days at 20 °C, resulting in a 5x2x3 factorial design. The application of T. harzianum only brought benefits to the control of brown rot when combined with the fungicide captan, at zero day shelf life. After two days, there was a greater skin darkening in peaches treated with T. harzianum compared with peaches without the treatment, except for peaches treated with the fungicide iprodione and T. harzianum The application of T. harzianum during postharvest showed no benefits for the control of brown rot, however, the association with fungicides reduced the incidence of Rhizopus stolonifer during the shelf life.

  18. Biologically inspired molecular machines driven by light. Optimal control of a unidirectional rotor

    International Nuclear Information System (INIS)

    We investigate the extent to which unidirectional intramolecular torsional motion can be created in an oriented bicyclic model system driven solely by laser light. We apply the machinery of quantum control via specifically tailored laser pulses to induce such motion, eliminating the need for the thermally constrained steps conventionally used in molecular motor systems. Our approach does not rely on specific details of the potential surfaces to create a preferred direction. Rather, we use matter-field interaction and the tools of coherent optimal control to create a wave packet with nonzero angular momentum among unbound torsional states on an excited electronic surface. Analysis of the results of the control algorithm provides general insight into when and how optimal control theory can find solutions that could not be generated through simple intuitive schemes. We find that, under constrained polarization, the control algorithm reduces to a simple intuitive coherent control strategy wherein a first IR pulse creates a non-stationary wave packet on the ground surface and a subsequent UV pulse transfers it to the excited state. Allowing for polarization shaping, however, we find new control routes that go beyond the intuitive scheme.

  19. Biological control of fouling incrustation on the scallop Nodipecten nodosus (Linnaeus, 1758 cultured in Ubatuba, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Rogerio Stojanov Bueno

    2009-12-01

    Full Text Available This experiment was developed at the marine farm of the São Paulo State Fisheries Institute in Ubatuba, SP, Brazil, aiming to compare the efficiency of three organisms (the sea urchins Echinometra lucunter, Lytechinus variegatus and the gastropod Tegula viridula in controlling fouling incrustation in lantern net and on Nodipecten nodosus valves. Scallops measuring 32.6 + 4.9mm of initial height were cultivated in eight Japanese lanterns with five floors each, at a density of 25 scallops/floor, according to the following delineament: T1 – control (scallops alone; T2 – scallops with E. lucunter; T3 – scallops with L. variegatus; T4 – scallops with T. viridula. Densities of the bio-controllers were: four (E. lucunter, three (L. variegatus and 15 animals/floor (T. viridula. The experiment was finished 150 days later and the remaining fouling in the lanterns and on the scallops valves was removed and weighed (dry weights. The sea-urchin species E. lucunter and L. variegatus were significantly more efficient in removing the lantern fouling (86% and 59% relative to the control treatment respectively, but there were no significant differences among the biocontrollers in controlling the fouling on the scallop valves. These results suggest that biological control can be helpful as an auxiliary method in scallop culture fouling removal.

  20. Paecilomyces lilacinus and Verticillium chlamydosporium Fungi as Biological Control of Fasciolosis

    Directory of Open Access Journals (Sweden)

    Riza Zainuddin Ahmad

    2013-09-01

    Full Text Available Fasciolosis is a worm disease caused of Fasciola gigantica and an important problem in husbandry especially for cattle. Controlling of this worm disease can be conducted by prevention and treatment. The use of antihelminthic is commonly causes a resistance problem. Natural control by mold such as Paecilomyces lilacinus and Verticillium chlamydosporium can be applied to reduce egg of F. gigantica. Although it was recently found, in vitro study gave satisfied result. This gives a new hope in controlling the disease although the extend application still needs to be studied. This paper discussed about the use of P. lilacinus and V. chlamydosporium for reducing F. gigantica population.

  1. Importance of temperature control for HEFLEX, a biological experiment for Spacelab 1. [plant gravitational physiology study

    Science.gov (United States)

    Chapman, D. K.; Brown, A. H.

    1979-01-01

    The importance of temperature control to HEFLEX, a Spacelab experiment designed to measure kinetic properties of Helianthis nutation in a low-g environment, is discussed. It is argued that the development of the HEFLEX experiment has been severely hampered by the inadequate control of ambient air temperature provided by the spacecraft module design. A worst case calculation shows that delivery of only 69% of the maximum yield of useful data from the HEFLEX system is guaranteed; significant data losses from inadequate temperature control are expected. The magnitude of the expected data losses indicates that the cost reductions associated with imprecise temperature controls may prove to be a false economy in the long term.

  2. NEW ORGANIC APPROACH TO PARASITES: Biological control of parasitic roundworms in organic laying hens using microfungi

    OpenAIRE

    Thapa, Sundar; Meyling, Nicolai V.; Thamsborg, Stig Milan; Mejer, Helena

    2013-01-01

    Microfungi can kill chicken roundworm eggs. This project investigates the use of naturally occuring soil microfungi to clean up contaminated pastures and bedding material, thereby controlling roundworm infections in organic laying hens.

  3. Agronomy of strip intercropping broccoli with alyssum for biological control of aphids

    Science.gov (United States)

    Organic broccoli growers in California typically control aphids by intercropping broccoli with strips of alyssum (Lobularia maritima (L.) Desv.) which attracts hoverflies (Diptera: Syrphidae) that are important predators of aphids. A three year study with transplanted organic broccoli in Salinas, ...

  4. Crop association to improve biological control: case study on pea and wheat aphids

    OpenAIRE

    Chevalier Mendes Lopes, Thomas; Bodson, Bernard; Francis, Frédéric

    2013-01-01

    Nowadays, strategies used to control aphids in fields of pea, Pisum sativum L., and wheat, Triticum aestivum L., still rely on synthetic insecticides which have negative effects on the environment and human health. This research focused on the development of sustainable alternative methods, with special emphasis on cultural practices and plant management systems. Increasing the diversity within crops may have several beneficial effects on pest control, creating attractive habitats for indigen...

  5. Controlling potassium selectivity and proton blocking in a hybrid biological/solid-state polymer nanoporous membrane.

    Science.gov (United States)

    Balme, Sébastien; Picaud, Fabien; Kraszewski, Sebastian; Déjardin, Philippe; Janot, Jean Marc; Lepoitevin, Mathilde; Capomanes, Jhon; Ramseyer, Christophe; Henn, François

    2013-05-01

    Specific separations of protons and cations are usually performed by electromembrane processes, which require external electric energy. An easier process would be using a membrane able to separate both entities by passive diffusion. Presently, such synthetic nanoporous membranes do not exist. Here, we report the production of a robust hybrid biological/artificial solid-state membrane, which allows selective permeation of alkali metal cations without competing or concurrent permeation of protons. This membrane is simple to prepare and is based on the hydrophobic nature of the polymeric pore walls, and the confined gramicidin A molecules within. This work opens a new route for separation in the domain of nanobiofiltration, especially for tunable nanodevices based on differential ion conduction, with a fundamental understanding of the confinement mechanism.

  6. Do new Access and Benefit Sharing procedures under the Convention on Biological Diversity threaten the future of biological control? Supplemental material (case studies, natural enemy releases, country views concerning ABS)

    OpenAIRE

    Cock, M.J.W.; Lenteren, van, J.C.; Brodeur, J; Barratt, I.P.; Bigler, F.; Bolckmans, K.; Cônsoli, F.L.; Haas, F.; Mason, P.G.; J.R.P. PARRA

    2010-01-01

    Under the Convention on Biological Diversity (CBD) countries have sovereign rights over their genetic resources. Agreements governing the access to these resources and the sharing of the benefits arising from their use need to be established between involved parties [i.e. Access and Benefit Sharing (ABS)]. This also applies to species collected for potential use in biological control. Recent applications of CBD principles have already made it difficult or impossible to collect and export natu...

  7. Controlling potassium selectivity and proton blocking in a hybrid biological/solid-state polymer nanoporous membrane

    Science.gov (United States)

    Balme, Sébastien; Picaud, Fabien; Kraszewski, Sebastian; Déjardin, Philippe; Janot, Jean Marc; Lepoitevin, Mathilde; Capomanes, Jhon; Ramseyer, Christophe; Henn, François

    2013-04-01

    Specific separations of protons and cations are usually performed by electromembrane processes, which require external electric energy. An easier process would be using a membrane able to separate both entities by passive diffusion. Presently, such synthetic nanoporous membranes do not exist. Here, we report the production of a robust hybrid biological/artificial solid-state membrane, which allows selective permeation of alkali metal cations without competing or concurrent permeation of protons. This membrane is simple to prepare and is based on the hydrophobic nature of the polymeric pore walls, and the confined gramicidin A molecules within. This work opens a new route for separation in the domain of nanobiofiltration, especially for tunable nanodevices based on differential ion conduction, with a fundamental understanding of the confinement mechanism.Specific separations of protons and cations are usually performed by electromembrane processes, which require external electric energy. An easier process would be using a membrane able to separate both entities by passive diffusion. Presently, such synthetic nanoporous membranes do not exist. Here, we report the production of a robust hybrid biological/artificial solid-state membrane, which allows selective permeation of alkali metal cations without competing or concurrent permeation of protons. This membrane is simple to prepare and is based on the hydrophobic nature of the polymeric pore walls, and the confined gramicidin A molecules within. This work opens a new route for separation in the domain of nanobiofiltration, especially for tunable nanodevices based on differential ion conduction, with a fundamental understanding of the confinement mechanism. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00564j

  8. Beauveria bassiana Strains for Biological Control of Cosmopolites sordidus (Germ. (Coleoptera: Curculionidae in Plantain

    Directory of Open Access Journals (Sweden)

    Marilene Fancelli

    2013-01-01

    Full Text Available The objective of this study was to select strains of Beauveria bassiana for controlling Cosmopolites sordidus (Germ. in plantain farms (cv. Terra of the “Recôncavo” and southern regions in the state of Bahia, Brazil. The virulence of 32 B. bassiana isolates against C. sordidus was determined under laboratory conditions. Three isolates (CNPMF 407, CNPMF 218, and CNPMF 416 were selected for evaluation under field conditions in plantations located in the counties of Mutuípe and Wenceslau Guimarães. Population of C. sordidus was estimated every 15 days by using pseudostem traps. The efficiency of the three strains of B. bassiana was compared to chemical control (carbofuran, 4g/trap and absence of control. Carbofuran caused around 90% of adult mortality after 12 months, with a reduction in the population of C. sordidus since the first evaluation. A low number of trapped insects was observed in the fungus-treated plots, suggesting the efficiency of the isolates in controlling the C. sordidus population. The strain CNPMF 218 was the most efficient in controlling C. sordidus adults in both locations, causing around 20% mortality, leading to 40% population size reduction after 12 months.

  9. Estimation and robust control of microalgae culture for optimization of biological fixation of CO2

    International Nuclear Information System (INIS)

    This thesis deals with the optimization of carbon dioxide consumption by microalgae. Indeed, following several current environmental issues primarily related to large emissions of CO2, it is shown that microalgae represent a very promising solution for CO2 mitigation. From this perspective, we are interested in the optimization strategy of CO2 consumption through the development of a robust control law. The main aim is to ensure optimal operating conditions for a Chlorella vulgaris culture in an instrumented photo-bioreactor. The thesis is based on three major axes. The first one concerns growth modeling of the selected species based on a mathematical model reflecting the influence of light and total inorganic carbon concentration. For the control context, the second axis is related to biomass estimation from the real-time measurement of dissolved carbon dioxide. This step is necessary for the control part due to the lack of affordable real-time sensors for this kind of measurement. Three observers structures have been studied and compared: an extended Kalman filter, an asymptotic observer and an interval observer. The last axis deals with the implementation of a non-linear predictive control law coupled to the estimation strategy for the regulation of the cellular concentration around a value which maximizes the CO2 consumption. Performance and robustness of this control law have been validated in simulation and experimentally on a laboratory-scale instrumented photo-bioreactor. This thesis represents a preliminary study for the optimization of CO2 mitigation strategy by microalgae. (author)

  10. Modified Primers for the Identification of Nonpathogenic Fusarium oxysporum Isolates That Have Biological Control Potential against Fusarium Wilt of Cucumber in Taiwan

    OpenAIRE

    Chaojen Wang; Yisheng Lin; Yinghong Lin; Wenhsin Chung

    2013-01-01

    Previous investigations demonstrated that Fusarium oxysporum (Fo), which is not pathogenic to cucumbers, could serve as a biological control agent for managing Fusarium wilt of cucumber caused by Fo f. sp. cucumerinum (Foc) in Taiwan. However, thus far it has not been possible to separate the populations of pathogenic Fo from the nonpathogenic isolates that have biological control potential through their morphological characteristics. Although these two populations can be distinguished from o...

  11. Molecular mechanisms of nematode-nematophagous microbe interactions: basis for biological control of plant-parasitic nematodes.

    Science.gov (United States)

    Li, Juan; Zou, Chenggang; Xu, Jianping; Ji, Xinglai; Niu, Xuemei; Yang, Jinkui; Huang, Xiaowei; Zhang, Ke-Qin

    2015-01-01

    Plant-parasitic nematodes cause significant damage to a broad range of vegetables and agricultural crops throughout the world. As the natural enemies of nematodes, nematophagous microorganisms offer a promising approach to control the nematode pests. Some of these microorganisms produce traps to capture and kill the worms from the outside. Others act as internal parasites to produce toxins and virulence factors to kill the nematodes from within. Understanding the molecular basis of microbe-nematode interactions provides crucial insights for developing effective biological control agents against plant-parasitic nematodes. Here, we review recent advances in our understanding of the interactions between nematodes and nematophagous microorganisms, with a focus on the molecular mechanisms by which nematophagous microorganisms infect nematodes and on the nematode defense against pathogenic attacks. We conclude by discussing several key areas for future research and development, including potential approaches to apply our recent understandings to develop effective biocontrol strategies. PMID:25938277

  12. Molecular mechanisms of nematode-nematophagous microbe interactions: basis for biological control of plant-parasitic nematodes.

    Science.gov (United States)

    Li, Juan; Zou, Chenggang; Xu, Jianping; Ji, Xinglai; Niu, Xuemei; Yang, Jinkui; Huang, Xiaowei; Zhang, Ke-Qin

    2015-01-01

    Plant-parasitic nematodes cause significant damage to a broad range of vegetables and agricultural crops throughout the world. As the natural enemies of nematodes, nematophagous microorganisms offer a promising approach to control the nematode pests. Some of these microorganisms produce traps to capture and kill the worms from the outside. Others act as internal parasites to produce toxins and virulence factors to kill the nematodes from within. Understanding the molecular basis of microbe-nematode interactions provides crucial insights for developing effective biological control agents against plant-parasitic nematodes. Here, we review recent advances in our understanding of the interactions between nematodes and nematophagous microorganisms, with a focus on the molecular mechanisms by which nematophagous microorganisms infect nematodes and on the nematode defense against pathogenic attacks. We conclude by discussing several key areas for future research and development, including potential approaches to apply our recent understandings to develop effective biocontrol strategies.

  13. The biology of appetite control: Do resting metabolic rate and fat-free mass drive energy intake?

    Science.gov (United States)

    Blundell, J E; Finlayson, G; Gibbons, C; Caudwell, P; Hopkins, M

    2015-12-01

    The prevailing model of homeostatic appetite control envisages two major inputs; signals from adipose tissue and from peptide hormones in the gastrointestinal tract. This model is based on the presumed major influence of adipose tissue on food intake. However, recent studies have indicated that in obese people fat-free mass (FFM) is strongly positively associated with daily energy intake and with meal size. This effect has been replicated in several independent groups varying in cultural and ethnic backgrounds, and appears to be a robust phenomenon. In contrast fat mass (FM) is weakly, or mildly negatively associated with food intake in obese people. In addition resting metabolic rate (RMR), a major component of total daily energy expenditure, is also associated with food intake. This effect has been replicated in different groups and is robust. This action is consistent with the proposal that energy requirements — reflected in RMR (and other aspects of energy expenditure) constitute a biological drive to eat. Consistent with its storage function, FM has a strong inhibitory effect on food intake in lean subjects, but this effect appears to weaken dramatically as adipose tissue increases. This formulation can account for several features of the development and maintenance of obesity and provides an alternative, and transparent, approach to the biology of appetite control. PMID:26037633

  14. Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.).

    Science.gov (United States)

    Rocha, Rafaeli; da Luz, Daniela Eleutério; Engels, Cibelle; Pileggi, Sônia Alvim Veiga; de Souza Jaccoud Filho, David; Matiello, Rodrigo Rodrigues; Pileggi, Marcos

    2009-01-01

    Biological control consists of using one organism to attack another that may cause economic damage to crops. Integrated Pest Management (IPM) is a very common strategy. The white mold produced by Sclerotinia sclerotiorum (Lib.) causes considerable damage to bean crops. This fungus is a soil inhabitant, the symptoms of which are characterized by water-soaked lesions covered by a white cottony fungal growth on the soil surface and/or the host plant. Possible biological control agents taken from plants are being investigated as phytopathogen inhibitors. These are endophytic microorganisms that inhabit the intercellular spaces of vegetal tissues and are often responsible for antimicrobial production. The objective of the present study was to select endophytic fungi isolated from comfrey (Symphytum officinale L.) leaves with in vitro antagonist potential against the phytopathogenic fungus S. sclerotiorum. Twelve isolates of endophytic fungi and a pathogenic strain of S. sclerotiorum were used in the challenge method. With the aid of this method, four endophytes with the best antagonistic activity against S. sclerotiorum were selected. Pathogen growth inhibition zones were considered indicative of antibiosis. The percentages of pathogenic mycelia growth were measured both with and without the antagonist, resulting in growth reductions of 46.7% to 50.0% for S. sclerotiorum. These analyses were performed by evaluating the endophytic/pathogenic mycelia growth in mm/day over an eight-day period of antagonistic tests. PMID:24031320

  15. Biological control of crown gall on grapevine and root colonization by nonpathogenic Rhizobium vitis strain ARK-1.

    Science.gov (United States)

    Kawaguchi, Akira

    2013-01-01

    A nonpathogenic strain of Rhizobium vitis ARK-1 was tested as a biological control agent for grapevine crown gall. When grapevine roots were soaked in a cell suspension of strain ARK-1 before planting in the field, the number of plants with tumors was reduced. The results from seven field trials from 2009 to 2012 were combined in a meta-analysis. The integrated relative risk after treatment with ARK-1 was 0.15 (95% confidence interval: 0.07-0.29, P0.001), indicating that the disease incidence was significantly reduced by ARK-1. In addition, the results from four field trials from 2007 to 2009 using R. vitis VAR03-1, a previously reported biological control agent for grapevine crown gall, were combined in a meta-analysis. The integrated relative risk after treatment with VAR03-1 was 0.24 (95% confidence interval: 0.11-0.53, P0.001), indicating the superiority of ARK-1 in inhibiting grapevine crown gall over VAR03-1 under field conditions. ARK-1 did not cause necrosis on grapevine shoot explants. ARK-1 established populations on roots of grapevine tree rootstock and persisted inside roots for two years.

  16. De Novo Analysis of the Transcriptome of Meloidogyne enterolobii to Uncover Potential Target Genes for Biological Control.

    Science.gov (United States)

    Li, Xiangyang; Yang, Dan; Niu, Junhai; Zhao, Jianlong; Jian, Heng

    2016-01-01

    Meloidogyne enterolobii is one of the obligate biotrophic root-knot nematodes that has the ability to reproduce on many economically-important crops. We carried out de novo sequencing of the transcriptome of M. enterolobii using Roche GS FLX and obtained 408,663 good quality reads that were assembled into 8193 contigs and 31,860 singletons. We compared the transcripts in different nematodes that were potential targets for biological control. These included the transcripts that putatively coded for CAZymes, kinases, neuropeptide genes and secretory proteins and those that were involved in the RNAi pathway and immune signaling. Typically, 75 non-membrane secretory proteins with signal peptides secreted from esophageal gland cells were identified as putative effectors, three of which were preliminarily examined using a PVX (pGR107)-based high-throughput transient plant expression system in Nicotiana benthamiana (N. benthamiana). Results showed that these candidate proteins suppressed the programmed cell death (PCD) triggered by the pro-apoptosis protein BAX, and one protein also caused necrosis, suggesting that they might suppress plant immune responses to promote pathogenicity. In conclusion, the current study provides comprehensive insight into the transcriptome of M. enterolobii for the first time and lays a foundation for further investigation and biological control strategies. PMID:27598122

  17. Size limitation on zebra mussels consumed by freshwater drum may preclude the effectiveness of drum as a biological controller

    Science.gov (United States)

    French, John R. P., III; Love, Joy G.

    1995-01-01

    The septa lengths of bivalve shells were used to estimate shell lengths of the largest zebra mussels (Dreissena polymorpha) crushed and consumed by freshwater drum (Aplodinotus grunniens) to determine if size limitation could preclude the effectiveness of drum as a biological controller of the zebra mussel. We examined gut samples of drum (273 to 542 mm long) collected from western Lake Erie in 1991, found the largest mussel (shell length = 21.4 mm) in the 11th largest drum (TL = 405 mm), and observed a reduction of mussel size in larger drum. The lack of a relationship between mussel size and drum size for larger specimens suggests that either drum prefer smaller mussels or the gape between the upper and lower pharyngeal teeth restricts drum feeding to zebra mussels of limited size. Although drum may reduce zebra mussel populations, because of the apparent size limitation of prey it is unlikely that drum would be fully effective as a biological controller; thus, this fish should not be introduced beyond its native range for that purpose.

  18. Selection of endophytic fungi from comfrey (Symphytum officinale L.) for in vitro biological control of the phytopathogen Sclerotinia sclerotiorum (Lib.)

    Science.gov (United States)

    Rocha, Rafaeli; da Luz, Daniela Eleutério; Engels, Cibelle; Pileggi, Sônia Alvim Veiga; de Souza Jaccoud Filho, David; Matiello, Rodrigo Rodrigues; Pileggi, Marcos

    2009-01-01

    Biological control consists of using one organism to attack another that may cause economic damage to crops. Integrated Pest Management (IPM) is a very common strategy. The white mold produced by Sclerotinia sclerotiorum (Lib.) causes considerable damage to bean crops. This fungus is a soil inhabitant, the symptoms of which are characterized by water-soaked lesions covered by a white cottony fungal growth on the soil surface and/or the host plant. Possible biological control agents taken from plants are being investigated as phytopathogen inhibitors. These are endophytic microorganisms that inhabit the intercellular spaces of vegetal tissues and are often responsible for antimicrobial production. The objective of the present study was to select endophytic fungi isolated from comfrey (Symphytum officinale L.) leaves with in vitro antagonist potential against the phytopathogenic fungus S. sclerotiorum. Twelve isolates of endophytic fungi and a pathogenic strain of S. sclerotiorum were used in the challenge method. With the aid of this method, four endophytes with the best antagonistic activity against S. sclerotiorum were selected. Pathogen growth inhibition zones were considered indicative of antibiosis. The percentages of pathogenic mycelia growth were measured both with and without the antagonist, resulting in growth reductions of 46.7% to 50.0% for S. sclerotiorum. These analyses were performed by evaluating the endophytic/pathogenic mycelia growth in mm/day over an eight-day period of antagonistic tests. PMID:24031320

  19. Biological Control Against the Cowpea Weevil (Callosobruchus Chinensis L., Coleoptera: Bruchidae Using Essential Oils of Some Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Fatiha Righi Assia

    2014-07-01

    Full Text Available Chickpea (Cicer arietinum L. is a valuable foodstuff but unfortunately this legume is prone to insect attacks from the chick pea weevil (Callosobruchus chinensis L.. This serious pest damages the chickpea and causes decreases in the yield and in the nutritional quality. Biological control is being used to deal with this problem. We tried different doses of the essential oils of three new medicinal plants, namely Salvia verbenaca L., Scilla maritima L., and Artemisia herba-alba Asso to limit the damage of the chick pea weevil pest, and to protect consumer’s health. To determine the effect and efficiency of the oil, the tests were conducted using the different biological parameters of fertility, longevity, and fecundity, under controlled temperature and relative humidity (28°C and 75%. The effectiveness of organic oils was demonstrated. We tested these oils on the germination of seeds. The obtained results showed that the tested plant oils have a real organic insecticide effect. The essential oil of Artemisia proved most effective as a biocide; achieving a mortality rate of 100%. A significant reduction in longevity was observed under the effect of 30 μl of S. maritima (1.3 days and S. verbenaca (2.8, 4.6 days, respectively, for males and females compared to 8 and 15 days for the control. For fecundity, an inhibition of oviposition was obtained using 30 μl of Salvia and Scilla essential oils. The test on the seed germination using different essential oils, showed no damage to the germinating seeds. The germination rate was 99%. These findings suggest that the tested plants can be used as a bioinsecticide for control of the C. chinensis pest of stored products.

  20. Mosquito vector biology and control in Latin America - a 23rd symposium

    Science.gov (United States)

    The 23nd Annual Latin American Symposium presented by the American Mosquito Control Association (AMCA) was held as part of the 79th Annual Meeting in Atlantic City, NJ in February 2013. The principal objective, as for the previous 22 symposia, was to promote participation in the AMCA by vector contr...

  1. Traps containing carvacrol, a biological approach for the control of Dermanyssus gallinae.

    Science.gov (United States)

    Barimani, Alireza; Youssefi, Mohammad Reza; Tabari, Mohaddeseh Abouhosseini

    2016-09-01

    Resistance to conventional synthetic pesticides has been widely reported in Dermanyssus gallinae in different aviary systems. Cardboard traps containing acaricides had been introduced as a successive device for collection and control of the poultry red mite. The present study assessed field efficacy of traps containing carvacrol in the control and reduction of D. gallinae in laying poultry farm. Two different carvacrol-based formulations were tested for their toxicity and possible repellent activity on D. gallinae to determine the most appropriate formulation and concentration to be used in the field study. In vitro tests confirmed that 1 % carvacrol formulation with ethoxylated castor oil as emulsifier was significantly toxic to D. gallinae without any dissuading effect in comparison to ethanol and higher concentrations of carvacrol (p < 0.05). A subsequent in vivo experiment in a cage system laying farm demonstrated significant acaricidal activity for traps containing 1 % carvacrol. Throughout the study, untreated cardboard traps were used for monitoring mite populations. Carvacrol-impregnated traps were efficacious in the control of D. gallinae and led to over 92 % reduction in mite's population after 2 week of application. Toxic effects of carvacrol maintained through 2 weeks after the last application of traps. Results of the present study suggested that effective control of the poultry red mite can be achieved by traps containing carvacrol. These traps can be used safely in poultry facilities without any concern about residues in eggs, meat, and environment. PMID:27156342

  2. Plant effects on biological control of spider mites in the ornamental crop Gerbera

    NARCIS (Netherlands)

    Krips, O.E.

    2000-01-01

    IntroductionThe spider mite Tetranychus urticae Koch is an important pest in many greenhouse crops. In vegetables it can be successfully controlled with the predatory mite Phytoseiulus persimilis Athias-Henriot, a specialist predator of spider mites (Helle & Sabelis, 1985). However,

  3. Reduced biological control and enhanced chemical pest management in the evolution of fungus farming in ants

    DEFF Research Database (Denmark)

    Fernández-Marín, Hermógenes; Zimmerman, Jess K; Nash, David R;

    2009-01-01

    antibiotics are narrow-spectrum and control a fungus (Escovopsis) that parasitizes the ants' fungal symbiont, and (ii) MG secretions have broad-spectrum activity and protect ants and brood. We assessed the relative importance of these lines of defence, and their activity spectra, by scoring abundance...

  4. Tsetse flies: their biology and control using area-wide integrated pest management approaches.

    Science.gov (United States)

    Vreysen, Marc J B; Seck, Momar Talla; Sall, Baba; Bouyer, Jérémy

    2013-03-01

    Tsetse flies are the cyclical vectors of trypanosomes, the causative agents of 'sleeping sickness' or human African trypanosomosis (HAT) in humans and 'nagana' or African animal trypanosomosis (AAT) in livestock in Sub-saharan Africa. Many consider HAT as one of the major neglected tropical diseases and AAT as the single greatest health constraint to increased livestock production. This review provides some background information on the taxonomy of tsetse flies, their unique way of reproduction (adenotrophic viviparity) making the adult stage the only one easily accessible for control, and how their ecological affinities, their distribution and population dynamics influence and dictate control efforts. The paper likewise reviews four control tactics (sequential aerosol technique, stationary attractive devices, live bait technique and the sterile insect technique) that are currently accepted as friendly to the environment, and describes their limitations and advantages and how they can best be put to practise in an IPM context. The paper discusses the different strategies for tsetse control i.e. localised versus area-wide and focusses thereafter on the principles of area-wide integrated pest management (AW-IPM) and the phased-conditional approach with the tsetse project in Senegal as a recent example. We argue that sustainable tsetse-free zones can be created on Africa mainland provided certain managerial and technical prerequisites are in place.

  5. Biology and Control of Insect and Related Pests of Livestock in Wyoming. MP-23.

    Science.gov (United States)

    Lloyd, John E.

    This document provides information that a potential insecticide applicator can utilize to safely and effectively control insects and related pests of livestock. The first section of the manual discusses the general methods of preparation and application of insecticides. The second section concerns itself with the recognition of insect problems,…

  6. Integration of biological mite control into outdoor strawberry production: a matter of efficacy and economy

    OpenAIRE

    Tuovinen, Tuomo

    2006-01-01

    Ten years experiences in experimental and practical fields prove that effective control of strawberry mite can be achieved by inundative introductions of the predatory mite Amblyseius cucumeris. Lately, Neoseiulus barkeri has been included to experiments compare its efficacy especially in higher strawberry mite densities.

  7. Epidemiology and biological control of grey mould in annual strawberry crops

    NARCIS (Netherlands)

    Boff, P.

    2001-01-01

    Intensive crop production has led to various undesirable side effects. Strawberry production is typically very input-intensive, in particular with respect to fungicides. In this thesis we attempt to develop a control strategy for strawberry grey mould caused by Botrytis cinerea Pers. using an ecolog

  8. Biology and Control of Snail Intermediate Host of Schistosoma japonicum in The People's Republic of China

    DEFF Research Database (Denmark)

    Li, Z.J.; Ge, J; Dai, J.R.;

    2016-01-01

    Schistosomiasis caused by Schistosoma japonicum is a severe parasitic disease in The People's Republic of China and imposed considerable burden on human and domestic animal health and socioeconomic development. The significant achievement in schistosomiasis control has been made in last 60years...

  9. Biological control of pedological and hydro-geomorphological processes in a deciduous forest ecosystem

    NARCIS (Netherlands)

    E.L.H. Cammeraat; A.M. Kooijman

    2009-01-01

    This study describes the effect of soil fauna andvegetation on the development of landscapes and how these actually control soil formation, geomorphological development and hydrological response. The study area is located in a semi-natural deciduous forest on marl in Luxembourg, with a strong textur

  10. Chemical and biological control of Sclerotinia stem rot in the soybean crop

    Directory of Open Access Journals (Sweden)

    Ciro Hideki Sumida

    2015-05-01

    Full Text Available It was evaluated the effect of fungicides and the microbial control agent Trichoderma harzianum on the inhibition of the carpogenic and ascospore germination of Sclerotinia sclerotiorum. This study also evaluated the chemical, fungicidal and microbial control of white mold or Sclerotinia stem rot of soybean in the field. Three experiments were conducted, as follows: 1 inhibition of carpogenic germination of sclerotia, 2 inhibition of ascospore germination, and 3 control of Sclerotinia stem rot in a soybean crop under field conditions. The treatments evaluated were fluazinam, procymidone, iprodione, thiophanate-methyl, carbendazim, benzalkonium chloride + fluazinam, and T. harzianum. Procymidone resulted in an inhibition of 13.5% and benzalkonium chloride in an inhibition of 13.9% in an ascospore germination test. Fluazinam and procymidone were the most effective in reducing the production of ascospores/apothecium, representing 65.6% and 82.4% of inhibition. Procymidone and fluazinam if combined or not with benzalkonium chloride were the most effective in controlling sclerotinia stem rot under field conditions when applied at the onset of flowering and 15 days later. In the 2009-10 harvest, these two fungicides reduced the incidence of Sclerotinia stem rot by 73.1 and 71.6% and in the 2010-11 harvest by 75.7 and 77.6%, respectively.

  11. Characterizing culturable microflora of nectarines: bacteria and their potential for biological control of postharvest fruit decay

    Science.gov (United States)

    Microorganisms isolated from fruit surfaces have been used to control postharvest decays of fruit. However, there is little information on microflora colonizing surfaces of fruits other than grapes, apples, and citrus. We characterized bacterial microflora on nectarine fruit surfaces during fruit ...

  12. Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands.

    Science.gov (United States)

    Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jörntell, Henrik; Kappers, Astrid M L; Kyriakopoulos, Kostas; Albu-Schäffer, Alin; Castellini, Claudio; Bicchi, Antonio

    2016-07-01

    The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project "The Hand Embodied" (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.

  13. Biological control of pests in protected cultivation: implementation in Latin America and successes in Europe

    NARCIS (Netherlands)

    Bueno, V.H.P.; Lenteren, van J.C.

    2010-01-01

    The area with greenhouse crops is estimated to be around 40,000 hectares in Latin America, of which approximately 60% is occupied with ornamentals. Several pests are responsible for losses in yield or quality of greenhouse crops production and pest control is still mainly by chemicals. However, ther

  14. Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands

    Science.gov (United States)

    Santello, Marco; Bianchi, Matteo; Gabiccini, Marco; Ricciardi, Emiliano; Salvietti, Gionata; Prattichizzo, Domenico; Ernst, Marc; Moscatelli, Alessandro; Jörntell, Henrik; Kappers, Astrid M. L.; Kyriakopoulos, Kostas; Albu-Schäffer, Alin; Castellini, Claudio; Bicchi, Antonio

    2016-07-01

    The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project "The Hand Embodied" (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.

  15. A review of Hyalomma scupense (Acari, Ixodidae in the Maghreb region: from biology to control

    Directory of Open Access Journals (Sweden)

    2014-01-01

    Full Text Available Hyalomma scupense (syn. Hyalomma detritum is a two-host domestic endophilic tick of cattle and secondarily other ungulates in the Maghreb region (Africa. This species transmits several pathogens, among which two are major livestock diseases: Theileria annulata and Theileria equi. Various other pathogens are also transmitted by this tick species, such as Anaplasma phagocytophilum and Ehrlichia bovis. Hyalomma scupense is common in sub-humid and semi-arid areas of several regions in the world, mainly in the Maghreb region. In this region, adults attach to animals during the summer season; larvae and nymphs attach to their hosts during autumn, but there is a regional difference in H. scupense phenology. There is an overlap between immature and adult ticks, leading in some contexts to a dramatic modification of the epidemiology of tick-borne diseases. This tick species attaches preferentially to the posterior udder quarters and thighs. Tick burdens can reach 130 ticks per animal, with a mean of 60 ticks. Calves are 70 times less infested than adult cattle. The control can be implemented through six options: (i rehabilitation of the farm buildings by roughcasting and smoothing the outer and inner surfaces of the enclosures and walls. This control option should be recommended to be combined with a thorough cleaning of the farm and its surrounding area. With regard to Theileria annulata infection, this control option is the most beneficial. (ii Acaricide application to animals during the summer season, targeting adults. (iii Acaricide application during the autumn period for the control of the immature stages. (iv Acaricide application to the walls: many field veterinarians have suggested this option but it is only partially efficient since nymphs enter deep into the cracks and crevices. It should be used if there is a very high tick burden or if there is a high risk of tick-borne diseases. (v Manual tick removal: this method is not efficient since the

  16. Review: Improving our knowledge of male mosquito biology in relation to genetic control programmes.

    Science.gov (United States)

    Lees, Rosemary Susan; Knols, Bart; Bellini, Romeo; Benedict, Mark Q; Bheecarry, Ambicadutt; Bossin, Hervé Christophe; Chadee, Dave D; Charlwood, Jacques; Dabiré, Roch K; Djogbenou, Luc; Egyir-Yawson, Alexander; Gato, René; Gouagna, Louis Clément; Hassan, Mo'awia Mukhtar; Khan, Shakil Ahmed; Koekemoer, Lizette L; Lemperiere, Guy; Manoukis, Nicholas C; Mozuraitis, Raimondas; Pitts, R Jason; Simard, Frederic; Gilles, Jeremie R L

    2014-04-01

    The enormous burden placed on populations worldwide by mosquito-borne diseases, most notably malaria and dengue, is currently being tackled by the use of insecticides sprayed in residences or applied to bednets, and in the case of dengue vectors through reduction of larval breeding sites or larviciding with insecticides thereof. However, these methods are under threat from, amongst other issues, the development of insecticide resistance and the practical difficulty of maintaining long-term community-wide efforts. The sterile insect technique (SIT), whose success hinges on having a good understanding of the biology and behaviour of the male mosquito, is an additional weapon in the limited arsenal against mosquito vectors. The successful production and release of sterile males, which is the mechanism of population suppression by SIT, relies on the release of mass-reared sterile males able to confer sterility in the target population by mating with wild females. A five year Joint FAO/IAEA Coordinated Research Project brought together researchers from around the world to investigate the pre-mating conditions of male mosquitoes (physiology and behaviour, resource acquisition and allocation, and dispersal), the mosquito mating systems and the contribution of molecular or chemical approaches to the understanding of male mosquito mating behaviour. A summary of the existing knowledge and the main novel findings of this group is reviewed here, and further presented in the reviews and research articles that form this Acta Tropica special issue. PMID:24252487

  17. Validation of cross-contamination control in biological safety cabinet for biotech/pharmaceutical manufacturing process.

    Science.gov (United States)

    Hu, Shih-Cheng; Shiue, Angus; Tu, Jin-Xin; Liu, Han-Yang; Chiu, Rong-Ben

    2015-12-01

    For class II, type A2 biological safety cabinets (BSC), NSF/ANSI Standard 49 should be conformed in cabinet airflow velocity derivation, particle contamination, and aerodynamic flow properties. However, there exists a potential problem. It has been built that the cabinet air flow stabilize is influenced by the quantity of downflow of air and the height above the cabinet exhaust opening. Three air downflow quantities were compared as an operating apparatus was placed from 20 to 40 cm above the bench of the cabinet. The results show that the BSC air downflow velocity is a function of increased sampling height, displaying that containment is improvingly permitted over product protection as the sampling height decreases. This study investigated the concentration gradient of particles at various heights and downflow air quantity from the bench of the BSC. Experiment results indicate that performance near the bench was better than in the rest of the BSC. In terms of height, the best cleanliness was measured at a height of 10 cm over the bench; it reduced actually with add in height. The empirical curves accommodate, founded on the concentration gradient of particle created was elaborated for evaluating the particle concentration at different heights and downflow air quantity from the source of the bench of the BSC. The particle image velocimetry system applied for BSC airflow research to fix amount of airflow patterns and air distribution measurement and results of measurements show how obstructions can greatly influence the airflow and contaminant transportation in a BSC.

  18. Nutrient control of eukaryote cell growth: a systems biology study in yeast

    Directory of Open Access Journals (Sweden)

    Lilley Kathryn S

    2010-05-01

    Full Text Available Abstract Background To elucidate the biological processes affected by changes in growth rate and nutrient availability, we have performed a comprehensive analysis of the transcriptome, proteome and metabolome responses of chemostat cultures of the yeast, Saccharomyces cerevisiae, growing at a range of growth rates and in four different nutrient-limiting conditions. Results We find significant changes in expression for many genes in each of the four nutrient-limited conditions tested. We also observe several processes that respond differently to changes in growth rate and are specific to each nutrient-limiting condition. These include carbohydrate storage, mitochondrial function, ribosome synthesis, and phosphate transport. Integrating transcriptome data with proteome measurements allows us to identify previously unrecognized examples of post-transcriptional regulation in response to both nutrient and growth-rate signals. Conclusions Our results emphasize the unique properties of carbon metabolism and the carbon substrate, the limitation of which induces significant changes in gene regulation at the transcriptional and post-transcriptional level, as well as altering how many genes respond to growth rate. By comparison, the responses to growth limitation by other nutrients involve a smaller set of genes that participate in specific pathways. See associated commentary http://www.biomedcentral.com/1741-7007/8/62

  19. Separating physical and biological controls on ten-year evapotranspiration fluctuations in an irrigated cropland in the North China Plain

    Science.gov (United States)

    Lei, Huimin

    2016-04-01

    The North China Plain, the largest agricultural production area in China, is a water-limited region where more than 50% of the nation's wheat and 33% of its maize production is grown. Evapotranspiration (ET) is a major component of the water balance in this agricultural ecosystem. Thus, hydrological cycle is very sensitive to the seasonal and interannual variability in ET. Understanding the variability in ET at different temporal scales and identifying out the dominant factor among the climatic factors (i.e., physical factors), crop factors (i.e., biological factors), and anthropogenic factors (i.e., irrigation) regulating ET is vital for promoting the development of agro-hydrological modeling. However, little is known about how ecosystem-level ET of irrigated cropland responds to these physical and biological factors over the long term, e.g., greater than 10 years. We have operated an eddy-covariance tower in a winter wheat-summer maize cropland for a 10-year period from 2005 through 2015, providing continuous measurements of ET and its relevant variables. The 10-year measurement period covers episodes of extremely high to low annual precipitation and higher air temperatures. The 10-year dataset provides opportunity to investigate the response of site-specific ecosystem ET to the variability of environmental factors. In this study, we reconcile an agro-hydrological model and the observations, to separate the physical and biological controls on ET fluctuations at different temporal scales. First, the model is calibrated carefully based on the observations. Second, a number of model runs are designed to disentangle the influence of climate, irrigation and biological drivers through constrained simulations. The climate drivers include precipitation, air temperature, air humidity, wind speed, and solar radiation, and the biological drivers include leaf area index and leaf-level stomatal conductance. In addition, the impacts of the variability in irrigation on ET will

  20. Control of radon and daughters in uranium mines and calculations on biologic effects

    International Nuclear Information System (INIS)

    A long range study under way by the Public Health Service since 1950 seeks to define the effects of uranium mining operations on the health of the miners and to derive data leading to the establishment of a healthful working environment. Although no evidence of health damage has been found among American miners, the European experience points to possible serious health effects. As a preventive measure, steps were therefore taken early in the industry's growth to safeguard the health of the miners. The current bulletin describes the results of the environmental study to date, together with the work of other investigators, with reference to methods of measuring atmospheric concentrations of radon and daughter products, the establishment of a safe working level for radon daughter products, and the development of effective control measures. It is believed that the material presented will be found useful by the industry and others, particularly in evaluating health hazards and in deriving economically feasible control methods

  1. Automatic control strategy for step feed anoxic/aerobic biological nitrogen removal process

    Institute of Scientific and Technical Information of China (English)

    ZHU Gui-bing; PENG Yong-zhen; WU Shu-yun; WANG Shu-ying

    2005-01-01

    Control of sludge age and mixed liquid suspended solids concentration in the activated sludge process is critical for ensuring effective wastewater treatment. A nonlinear dynamic model for a step-feed activated sludge process was developed in this study. The system is based on the control of the sludge age and mixed liquor suspended solids in the aerator of last stage by adjusting the sludge recycle and wastage flow rates respectively. The simulation results showed that the sludge age remained nearly constant at a value of 16 d in the variation of the influent characteristics. The mixed liquor suspended solids in the aerator of last stage were also maintained to a desired value of 2500 g/m3 by adjusting wastage flow rates.

  2. A Search and Improvement of Actinomycetes Strains by Gamma Radiation for Biological Control of Plant Pathogen

    International Nuclear Information System (INIS)

    Two hundred isolates of actinomycetes isolate from soil sample in Sakaerat Bioshere Reserve and Suwanvajokkasikit Field Corps Research Station were tested the ability of actinomycetes on chitinase production and inhibition on the growth of 3 phyto pathogenic fung: Fusarium sporotrichiodes, Rhizoctonia solani and Sclerotium rolfsii, It was found that 7 isolates showed good tendency to control the growth of phyto pathogenic fungi in the with and with chitin. To increase the ability on antifungal activity the select show were mutant using gamma irradiation of radiance 173 isolates of mutant actinomycetes we found that only 35 isolates showed higher in inhibitory effect on three phyto pathogenic fungi tested. three isolate. Three isolates of mutant strains, SJ9I-15, SG4I-17 and SG4I-38 and two isolates of wild type strain which are SJ9 and SG4 were selected for controlling phyto pathogenic fungi in the green house.

  3. Decreased Functional Diversity and Biological Pest Control in Conventional Compared to Organic Crop Fields

    OpenAIRE

    Jochen Krauss; Iris Gallenberger; Ingolf Steffan-Dewenter,

    2011-01-01

    Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were...

  4. Diversity and biological control of Sclerotium rolfsii, causal agent of stem rot of groundnut

    OpenAIRE

    Lê, N.C.

    2011-01-01

    Groundnut (Arachis hypogaea L.) is an economically important legume crop in Vietnam and many other countries worldwide. Stem rot disease, caused by the soil-borne fungus Sclerotium rolfsii Sacc., is a major yield limiting factor in groundnut cultivation. Current control methods mostly rely on the extensive use of fungicides and on cultural practices. Both methods are not always effective and repeated fungicide use can lead to resistance development in the pathogen population. To further impro...

  5. An Economic Assessment of Biological Control for Miconia calvescens in Hawaii

    OpenAIRE

    Megan Chock; Kimberly Burnett; Donna Lee

    2010-01-01

    Biocontrol, the introduction of organisms to control an unwanted species, has been cited as a powerful method to manage the invasive species Miconia calvescens in Hawaii. In addition to ecological advantages, biocontrol is often regarded as less costly than traditional methods despite the large initial investment. Currently, miconia in Hawaii is treated through aerial and manual operations, which cost over $1 million annually. Biocontrol for miconia in Hawaii began in 1997 and the search for ...

  6. Economic evaluation of biological rodent control using barn owls Tyto alba in alfalfa

    OpenAIRE

    Motro, Y.

    2011-01-01

    Rodents are common pests in various agricultural cultivations. Utilization of barn owls for rodent pest control has long been used. In Israel, the indirect effect of barn owl predation pressure on alfalfa crop yield has been examined. Using radio-telemetry, barn owls were tracked to form a density-distance function, which was later used to estimate predation pressure on whole fields. This function was utilized on all barn owls nesting in the vicinity to assess accumulated predation pressure o...

  7. Control Issues in High-speed AFM for Biological Applications: Collagen Imaging Example 1

    OpenAIRE

    Zou, Q; Leang, KK; Sadoun, E; Reed, MJ; Devasia, S

    2004-01-01

    This article considers the precision positioning problem associated with high-speed operation of the Atomic Force Microscope (AFM), and presents an inversion-based control approach to achieve precision positioning. Although AFMs have high (nanoscale) spatial resolution, a problem with current AFM systems is that they have low temporal resolution, i.e., AFM imaging is slow. In particular, current AFM imaging cannot be used to provide three-dimensional, time-lapse images of fast processes when ...

  8. Biological Control of Bipolaris sorokiniana on Tall Fescue by Stenotrophomonas maltophilia Strain C3.

    Science.gov (United States)

    Zhang, Z; Yuen, G Y

    1999-09-01

    ABSTRACT Stenotrophomonas maltophilia strain C3 was evaluated for control of leaf spot on tall fescue (Festuca arundinacea) caused by Bipolaris sorokiniana. In growth chamber experiments, C3 inhibited conidial germination on leaf surfaces and reduced lesion frequency and percent diseased leaf area compared with nontreated controls. The amount of leaf spot suppression was related to the C3 dose applied. The highest dose tested, 10(9) CFU/ml, prevented nearly all B. sorokiniana conidia from germinating on treated leaf surfaces and provided nearly complete suppression of lesion development. When colloidal chitin was added to C3 cell suspensions of 10(7) or 10(8) CFU/ml, biocontrol efficacy was significantly increased over C3 applied alone, whereas addition of chitin to a C3 cell suspension of 10(9) CFU/ml had no effect. In field experiments, application of C3 to tall fescue turf resulted in significant reductions in infection frequency and disease severity compared with nontreated controls. Strain C3 applied at 10(9) CFU/ml was more effective than C3 applied at 10(7) CFU/ml, and amendment of the lower dose with colloidal chitin enhanced its efficacy. Populations sizes of C3 established on foliage in a growth chamber and in the field were directly related to dose applied. Chitin amendments did not affect C3 population size.

  9. Biological control experiment of excess propagation of Cyclops for drinking water security

    Institute of Scientific and Technical Information of China (English)

    LIN Tao; CUI Fu-yi; LIU Dong-mei

    2007-01-01

    Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation.In this study,an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extaneous nutrient feeding.The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively,and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m3 of water.The growth of Cyclops may not be effectually controlled with lower biomass of fish(10 g),and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water.In addition,the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

  10. Parametric motion control of robotic arms: A biologically based approach using neural networks

    Science.gov (United States)

    Bock, O.; D'Eleuterio, G. M. T.; Lipitkas, J.; Grodski, J. J.

    1993-01-01

    A neural network based system is presented which is able to generate point-to-point movements of robotic manipulators. The foundation of this approach is the use of prototypical control torque signals which are defined by a set of parameters. The parameter set is used for scaling and shaping of these prototypical torque signals to effect a desired outcome of the system. This approach is based on neurophysiological findings that the central nervous system stores generalized cognitive representations of movements called synergies, schemas, or motor programs. It has been proposed that these motor programs may be stored as torque-time functions in central pattern generators which can be scaled with appropriate time and magnitude parameters. The central pattern generators use these parameters to generate stereotypical torque-time profiles, which are then sent to the joint actuators. Hence, only a small number of parameters need to be determined for each point-to-point movement instead of the entire torque-time trajectory. This same principle is implemented for controlling the joint torques of robotic manipulators where a neural network is used to identify the relationship between the task requirements and the torque parameters. Movements are specified by the initial robot position in joint coordinates and the desired final end-effector position in Cartesian coordinates. This information is provided to the neural network which calculates six torque parameters for a two-link system. The prototypical torque profiles (one per joint) are then scaled by those parameters. After appropriate training of the network, our parametric control design allowed the reproduction of a trained set of movements with relatively high accuracy, and the production of previously untrained movements with comparable accuracy. We conclude that our approach was successful in discriminating between trained movements and in generalizing to untrained movements.

  11. Biologically-inspired robust and adaptive multi-sensor fusion and active control

    Science.gov (United States)

    Khosla, Deepak; Dow, Paul A.; Huber, David J.

    2009-04-01

    In this paper, we describe a method and system for robust and efficient goal-oriented active control of a machine (e.g., robot) based on processing, hierarchical spatial understanding, representation and memory of multimodal sensory inputs. This work assumes that a high-level plan or goal is known a priori or is provided by an operator interface, which translates into an overall perceptual processing strategy for the machine. Its analogy to the human brain is the download of plans and decisions from the pre-frontal cortex into various perceptual working memories as a perceptual plan that then guides the sensory data collection and processing. For example, a goal might be to look for specific colored objects in a scene while also looking for specific sound sources. This paper combines three key ideas and methods into a single closed-loop active control system. (1) Use high-level plan or goal to determine and prioritize spatial locations or waypoints (targets) in multimodal sensory space; (2) collect/store information about these spatial locations at the appropriate hierarchy and representation in a spatial working memory. This includes invariant learning of these spatial representations and how to convert between them; and (3) execute actions based on ordered retrieval of these spatial locations from hierarchical spatial working memory and using the "right" level of representation that can efficiently translate into motor actions. In its most specific form, the active control is described for a vision system (such as a pantilt- zoom camera system mounted on a robotic head and neck unit) which finds and then fixates on high saliency visual objects. We also describe the approach where the goal is to turn towards and sequentially foveate on salient multimodal cues that include both visual and auditory inputs.

  12. Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid.

    Science.gov (United States)

    Jang, Ja Yeong; Choi, Yong Ho; Shin, Teak Soo; Kim, Tae Hoon; Shin, Kee-Sun; Park, Hae Woong; Kim, Young Ho; Kim, Hun; Choi, Gyung Ja; Jang, Kyoung Soo; Cha, Byeongjin; Kim, In Seon; Myung, Eul Jae; Kim, Jin-Cheol

    2016-01-01

    Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s) and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS). Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP) formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10%) and oxalic acid-WP8 (ai 8%), were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate). These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease. PMID:27258452

  13. IAEA quality control study on determining trace elements in biological matrices for air pollution research

    International Nuclear Information System (INIS)

    Analysis of lichens and mosses were routinely performed by 17 laboratories from 15 countries around the world, participating in a project coordinated by the International Atomic Energy Agency (IAEA). To improve and control the quality of such determinations, the IAEA organized a two-round interlaboratory exercise, which allowed the detection and removal of most of the pitfalls observed in the determination of 27 elements. The application of instrumental neutron activation analysis helped reveal poor recoveries in some laboratories due to incomplete digestion for a number of elements. The exercise emphasized the importance of achieving comparability of chemical measurements to a recognized reference. (author)

  14. Biology studies and improvement of Ceratitis capitata (Wiedemann) mass trapping control technique

    OpenAIRE

    Peñarrubia María, Esther

    2010-01-01

    Ceratitis capitata (Wiedemann) (mosca de la fruita), està considerada a nivell mundial com una de les plagues més destructives de fruits degut a la seva elevada capacitat de causar danys en la producció, la seva distribució global i al seu ampli rang d‟hostes. S‟ha desenvolupat un model eficaç de control integrat de plagues (IPM), que ha estat acceptat a Europa com estratègia de protecció vegetal per a una agricultura sostenible. L‟objectiu del present treball va ser l‟...

  15. Evaluation of biological control strategies for polyphagotarsonemus latus (banks) and phyllocoptruta oleivora (ashmead) on valencia orange

    OpenAIRE

    Imbachi L, Karol; Mesa C., Nora Cristina; Rodríguez T, Isaura Viviana; Gómez G, Ibete; Cuchimba, Mayra; Lozano, Héctor; Matabanchoy, Jesús Harvey; Carabalí, Arturo

    2013-01-01

    El daño ocasionado por los ácaros Polyphagotarsonemus latus (Banks) y Phyllocoptruta oleivora (Ashmead) en el cultivo de naranja Valencia (Citrus sinensis L.) es reconocido tanto por el impacto económico como por el dao externo de los frutos. En este trabajo se evaluó el efecto de agentes biológicos para el control de estas plagas en un cultivo comercial de naranja Valencia en el municipio de Caicedonia, Valle del Cauca, Colombia. Se usó un diseo de bloques completos al azar para evaluar los ...

  16. Biological control of Polymyxa betae, fungal vector of rhizomania disease of sugar beets in greenhouse conditions

    OpenAIRE

    Naraghi Laleh; Heydari Asghar; Askari Hassan; Pourrahim Reza; Marzban Rasoul

    2014-01-01

    Rhizomania is one of the most important diseases of sugar beet around the world – including in Iran. The disease causes a severe decrease in sugar yield and is a limiting factor in sugar beet cultivation. Control of the disease is very difficult due to the long-term survival of its fungal vector (Polymyxa betae) in the soil. In this study, we investigated the effects of antagonistic fungal isolates on the population of the resting structure (cystosorus) of P. betae, under greenhouse condition...

  17. Biology, epidemiology and control of Fusicladium eriobotryae, causal agent of loquat scab

    OpenAIRE

    González Domínguez, Elisa

    2014-01-01

    El moteado del níspero, causado por el hongo Fusicladium eriobotryae es la principal enfermedad que afecta al cultivo del níspero, produciendo pérdidas importantes en la cosecha en los años con condiciones climáticas adecuadas. Sin embargo, no existen estudios sobre la epidemiología y el control de esta enfermedad, por lo que éstos constituyen el principal objetivo de la presente Tesis. Para ello, se va ha caracterizar in vitro y en campo la influencia de las principales variables climáticas ...

  18. Characterization and mechanism of action of the biological control agent Pantoea agglomerans EPS125

    OpenAIRE

    Moreno González, M. del Carmen

    2006-01-01

    La soca EPS125 ha mostrat ser un efectiu agent de control biològic de diferents patògens fúngics de postcollita en diferents fruits. Degut a la seva elevada eficàcia, es va plantejar desenvolupar aquesta soca comercialment i per aquest motiu en el present treball es plantejà complementar la informació necessària pel seu registre. D'acord amb els resultats obtinguts mitjançant proves fenotípiques i genotípiques, la soca EPS125 queda inclosa dins l'espècie Pantoea agglomerans (Enterobacter aggl...

  19. Evaluation of Verticilum Chlamydosporium and Arrthrobotrys for Biological Control of Meloidogyne Incognita in Celery and Tomato

    International Nuclear Information System (INIS)

    The ability of nematode trapping fungi and egg-parasitic fungi to colonize and persist in the rhizosphere of crop plants is thought to be an important factor influencing the success of bi logical control of root infecting nematodes. In this study, two strains of an egg parasite fungus Verticillium chlamydosporium (Vc-10 and Vc-2M) and an isolate of the nematode-trapping fungus Arthrobotrys oligospora and persistence in the rhizosphere and tomato plants in a green house pot experiment. The isolates tested differed in their pathogenicity to M. incognita and survival in the rhizosphere. An isolate of Verticillum chlamydosporium (Vc-10) was the most virulent pathogen of the nematode. Root galling was slowest in tomato plants treated with V-10 (2.2); pots treated with this isolate had the lowest final soil population of infective juveniles; there was a 62.2% and 98.5% infections of eggs and egg masses respectively by Vc-10 on tomato plants. The two isolates of Verticillium chlamydosporium (Vc-10 and Vc2M) persisted in the soil and could be re-isolated from the rhizosphere and roots of tomato plants at least 16 weeks after soil application. The final inoculum density was, however higher for Vc-10 (1.35x105 cfu/g soil) than Vc-2M (9.25x104 cfu/g soil). Arthrobotrys oligospora on the other hand did not give any significant control of the nematode on both crops, there was severe galling on the roots of plants treated with this agent. It could not be re-isolated from the plant rhizosphere sixteen weeks after soil infestation. Lack of nematode control on both crops by A.oligo spora was attributed to it's poor on establishment in the plant rhizosphere; low density and roots penetration by infective juveniles before they were ensnared in the trapping devices of this fungal biocontrol agent. The fact that it could not be re-isolated from the rhizosphere may imply that the fungus did not survive in the rhizosphere in quantities enough to enhance nematode control

  20. Effects of grade control structures on fish passage, biological assemblages, and hydraulic environments in western Iowa streams: a multidisciplinary review

    Science.gov (United States)

    Thomas, J.T.; Culler, M.E.; Dermisis, D.C.; Pierce, Clay; Papanicolaou, A.N.; Stewart, T.W.; Larson, C.J.

    2011-01-01

    Land use changes and channelization of streams in the deep loess region of western Iowa have led to stream channel incision, altered flow regimes, increased sediment inputs, decreased habitat diversity and reduced lateral connectivity of streams and floodplains. Grade control structures (GCSs) are built in streams to prevent further erosion, protect infrastructure and reduce sediment loads. However, GCS can have a detrimental impact on fisheries and biological communities. We review three complementary biological and hydraulic studies on the effects of GCS in these streams. GCS with steep (≥1:4 rise : run) downstream slopes severely limited fish passage, but GCS with gentle slopes (≤1:15) allowed greater passage. Fish assemblages were dominated by species tolerant of degradation, and Index of Biotic Integrity (IBI) scores were indicative of fair or poor biotic integrity. More than 50% of fish species had truncated distributions. After modification of GCS to reduce slopes and permit increased passage, IBI scores increased and several species were detected further upstream than before modification. Total macroinvertebrate density, biomass and taxonomic diversity and abundance of ecologically sensitive taxa were greater at GCS than in reaches immediately upstream, downstream or ≥1 km from GCS. A hydraulic study confirmed results from fish passage studies; minimum depths and maximum current velocities at GCS with gentle slopes (≤1:15) were more likely to meet minimum criteria for catfish passage than GCS with steeper slopes. Multidisciplinary approaches such as ours will increase understanding of GCS-associated factors influencing fish passage, biological assemblage structure and other ecological relationships in streams.