bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrically wavelength‐tunable optical short‐pulse generation in a self‐seeding scheme with intensity controllable feedback
Authors: Wang D. N. , Zhang M.
Published: May 2003

A simple and robust system is presented to generate electrically wavelength‐tunable optical short pulses from a gain‐switched Fabry–Perot laser diode. The laser external cavity consists of a tunable filter and an erbium‐doped fiber amplifier, which provides wavelength selectivity and intensity controllable feedback. As a result, a side mode suppression ratio SMSR of better than 30 dB over the wavelength tuning range of 17.5 nm can be obtained. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 98–99, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10982
Method for calculating the scattering matrix of arbitrary microwave networks giving both internal and external scattering
Authors: Hallbjörner Paul
Published: May 2003

A general method for calculating the scattering matrix of an arbitrary microwave networks is presented. Compared to existing methods, it uses a simplified algorithm that makes no distinction between external and internal ports. It thereby achieves algorithmic simplicity, and provides waves internally in the network as well as scattered waves at the ports. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 99–102, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10983
An accurate tuning method for dual‐mode cavity filters
Authors: Lee Juseop , Uhm Man Seok , Yom In‐Bok , Lee Seong Pal
Published: May 2003

An accurate tuning method using a short‐ended dummy cavity is presented for dual‐mode cavity filters. Tuning is based on the match of the computed and measured phase responses of the reflection coefficient. An equivalent circuit model is adopted for computing the required phase response of the reflection coefficient. This method is applied to a 4‐pole longitudinal dual‐mode filter for demonstration. Good agreement is found between the experimental and computed responses. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 123–125, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10991
A reconfigurable Yagi antenna for wireless communications
Authors: Wahid P. F. , Ali M. A. , DeLoach B. C.
Published: May 2003

The design of a reconfigurable Yagi antenna that can operate at two frequencies, 2.4 GHz and 5.78 GHz, for use in wireless communications is presented. The Yagi can be reconfigured through the use of appropriate switches placed on the elements of the antenna. This paper shows the feasibility of this antenna and presents simulated and measured results at the two frequencies. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 140–141, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10997
Characterization of polo‐like kinase‐1 in rat oocytes and early embryos implies its functional roles in the regulation of meiotic maturation, fertilization, and cleavage
Authors: Fan Heng‐Yu , Tong Chao , Teng Chun‐Bo , Lian Li , Li Shi‐Wen , Yang Zeng‐Ming , Chen Da‐Yuan , Schatten Heide , Sun Qing‐Yuan
Published: May 2003

Polo‐like kinase 1 (Plk1) is a family of serine/threonine protein kinases that play important regulatory roles during mitotic cell cycle progression. In this study, Plk1 expression, subcellular localization, and possible functions during rat oocyte meiotic maturation, fertilization, and embryonic cleavages were studied by using RT‐PCR, Western blot, confocal microscopy, drug‐treatments, and antibody microinjection. Both the mRNA and protein of this kinase were detected in rat maturing oocytes and developing embryos. Confocal microscopy revealed that Plk1 distributed abundantly in the nucleus at the germinal vesicle (GV) stage, was associated with spindle poles during the formation of M‐phase spindle, and was translocated to the spindle mid‐zone at anaphase. In fertilized eggs, Plk1 was strongly stained in the cytoplasm between the apposing male and female pronuclei, from where microtubules radiated. Throughout cytokinesis, Plk1 was localized to the division plane, both during oocyte meiosis and embryonic mitosis. The specific subcellular distribution of Plk1 was distorted after disrupting the M‐phase spindle, while additional aggregation dots could be induced in the cytoplasm by taxol, suggesting its intimate association with active microtubule assembly. Plk1 antibody microinjection delayed the meiotic resumption and blocked the emission of polar bodies. In conclusion, Plk1 may be a multifunctional kinase that plays pivotal regulatory roles in microtubule assembly during rat oocyte meiotic maturation, fertilization, and early embryonic mitosis. Mol. Reprod. Dev. 65: 318–329, 2003. © 2003 Wiley‐Liss, Inc.
Nongenetic causes of hearing loss
Authors: Roizen Nancy J.
Published: May 2003

Nongenetic as well as genetic etiologies must be explored in the child with identified hearing loss. Graduates of the neonatal intensive care unit are at increased risk for developing hearing loss due to hypoxia, hyperbilirubinemia, very low birth weight, and ototoxic medications. Although meningitis has decreased in frequency, it is still a risk factor for hearing loss. Cytomegalovirus remains the most common congenital infection and a relatively common etiology of hearing loss, which can be progressive. Preventable causes of hearing loss include those caused by head trauma, noise, and ototoxic medications. Identification of the etiology of hearing loss can facilitate the development of a treatment and management plan. MRDD Research Reviews 2003;9:120–127. © 2003 Wiley‐Liss, Inc.
Proposed amino acid sequence and the 1.63 Å X‐ray crystal structure of a plant cysteine protease, ervatamin B: Some insights into the structural basis of its stability and substrate specificity
Authors: Biswas Sampa , Chakrabarti Chandana , Kundu Suman , Jagannadham Medicherla V. , Dattagupta Jiban K.
Published: May 2003

The crystal structure of a cysteine protease ervatamin B, isolated from the medicinal plant Ervatamia coronaria, has been determined at 1.63 Å. The unknown primary structure of the enzyme could also be traced from the high‐quality electron density map. The final refined model, consisting of 215 amino acid residues, 208 water molecules, and a thiosulfate ligand molecule, has a crystallographic R‐factor of 15.9% and a free R‐factor of 18.2% for F > 2σ(F). The protein belongs to the papain superfamily of cysteine proteases and has some unique properties compared to other members of the family. Though the overall fold of the structure, comprising two domains, is similar to the others, a few natural substitutions of conserved amino acid residues at the interdomain cleft of ervatamin B are expected to increase the stability of the protein. The substitution of a lysine residue by an arginine (residue 177) in this region of the protein may be important, because Lys → Arg substitution is reported to increase the stability of proteins. Another substitution in this cleft region that helps to hold the domains together through hydrogen bonds is Ser36, replacing a conserved glycine residue in the others. There are also some substitutions in and around the active site cleft. Residues Tyr67, Pro68, Val157, and Ser205 in papain are replaced by Trp67, Met68, Gln156, and Leu208, respectively, in ervatamin B, which reduces the volume of the S2 subsite to almost one‐fourth that of papain, and this in turn alters the substrate specificity of the enzyme. Proteins 2003;51:489–497. © 2003 Wiley‐Liss, Inc.
Endogenous tryptophan residues of cAPK regulatory subunit type IIβ reveal local variations in environments and dynamics
Authors: Zawadzki Kerri M. , Pan Chia‐Pin , Barkley Mary D. , Johnson David , Taylor Susan S.
Published: May 2003

The amino terminal dimerization/docking domain and the two‐tandem, carboxy‐terminal cAMP‐binding domains (A and B) of cAMP‐dependent protein kinase regulatory (R) subunits are connected by a variable linker region. In addition to providing a docking site for the catalytic subunit, the linker region is a major source of sequence diversity between the R‐subunit isoforms. The RIIβ isoform uniquely contains two endogenous tryptophan residues, one at position 58 in the linker region and the other at position 243 in cAMP‐binding domain A, which can act as intrinsic reporter groups of their dynamics and microenvironment. Two single‐point mutations, W58F and W243F, allowed the local environment of each Trp to be probed using steady‐state and time‐resolved fluorescence techniques. We report that: (a) the tryptophan fluorescence of the wild‐type protein largely reflects Trp243 emission; (2) cAMP selectively quenches Trp243 and thus acts as a cAMP sensor; (3) Trp58 resides in a highly solvated, unstructured, and mobile region of the protein; and (4) Trp243 resides in a stable, folded domain and is relatively buried and rigid within the domain. The use of endogenous Trp residues presents a non‐perturbing method for studying R‐subunit subdomain characteristics in addition to providing the first biophysical data on the RIIβ linker region. Proteins 2003;51:552–561. © 2003 Wiley‐Liss, Inc.
Insights into nonspecific binding of homeodomains from a structure of MATα2 bound to DNA
Authors: Aishima Jun , Wolberger Cynthia
Published: May 2003

The 2.1‐Å resolution crystal structure of the MATα2 homeodomain bound to DNA reveals the unexpected presence of two nonspecifically bound α2 homeodomains, in addition to the two α2 homeodomains bound to canonical α2 binding sites. One of the extra homeodomains makes few base‐specific contacts, while the other extra homeodomain binds to DNA in a previously unobserved manner. This unusually bound homeodomain is rotated on the DNA, making possible major groove contacts by side‐chains that normally do not contact the DNA. This alternate docking may represent one way in which homeodomains sample nonspecific DNA sequences. Proteins 2003;51:544–551. © 2003 Wiley‐Liss, Inc.
Evaluation of protein docking predictions using Hex 3.1 in CAPRI rounds 1 and 2
Authors: Ritchie David W.
Published: May 2003

This article describes and reviews our efforts using Hex 3.1 to predict the docking modes of the seven target protein–protein complexes presented in the CAPRI (Critical Assessment of Predicted Interactions) blind docking trial. For each target, the structure of at least one of the docking partners was given in its unbound form, and several of the targets involved large multimeric structures (e.g., Lactobacillus HPr kinase, hemagglutinin, bovine rotavirus VP6). Here we describe several enhancements to our original spherical polar Fourier docking correlation algorithm. For example, a novel surface sphere smothering algorithm is introduced to generate multiple local coordinate systems around the surface of a large receptor molecule, which may be used to define a small number of initial ligand‐docking orientations distributed over the receptor surface. High‐resolution spherical polar docking correlations are performed over the resulting receptor surface patches, and candidate docking solutions are refined by using a novel soft molecular mechanics energy minimization procedure. Overall, this approach identified two good solutions at rank 5 or less for two of the seven CAPRI complexes. Subsequent analysis of our results shows that Hex 3.1 is able to place good solutions within a list of ≤20 for four of the seven targets. This finding shows that useful in silico protein–protein docking predictions can now be made with increasing confidence, even for very large macromolecular complexes. Proteins 2003;52:98–106. © 2003 Wiley‐Liss, Inc.
A soft docking algorithm for predicting the structure of antibody‐antigen complexes
Authors: Li Chun Hua , Ma Xiao Hui , Chen Wei Zu , Wang Cun Xin
Published: May 2003

An efficient soft docking algorithm is described for predicting the mode of binding between an antibody and its antigen based on the three‐dimensional structures of the molecules. The basic tools are the “simplified protein” model and the docking algorithm of Wodak and Janin. The side‐chain flexibility of Arg, Lys, Asp, Glu, and Met residues on the protein surface is taken into account. A combined filtering technique is used to select candidate binding modes. After energy minimization, we calculate a scoring function, which includes electrostatic and desolvation energy terms. This procedure was applied to targets 04, 05, and 06 of CAPRI, which are complexes of three different camelid antibody VHH variable domains with pig α‐amylase. For target 06, two native‐like structures with a root‐mean‐square deviation < 4.0 Å relative to the X‐ray structure were found within the five top ranking structures. For targets 04 and 05, our procedure produced models where more than half of the antigen residues forming the epitope were correctly predicted, albeit with a wrong VHH domain orientation. Thus, our soft docking algorithm is a promising tool for predicting antibody‐antigen recognition. Proteins 2003;52:47–50. © 2003 Wiley‐Liss, Inc.
Protein–protein docking predictions for the CAPRI experiment
Authors: Gray Jeffrey J. , Moughon Stewart E. , Kortemme Tanja , Schueler‐Furman Ora , Misura Kira M.S. , Morozov Alexandre V. , Baker David
Published: May 2003

We predicted structures for all seven targets in the CAPRI experiment using a new method in development at the time of the challenge. The technique includes a low‐resolution rigid body Monte Carlo search followed by high‐resolution refinement with side‐chain conformational changes and rigid body minimization. Decoys (∼106 per target) were discriminated using a scoring function including van der Waals and solvation interactions, hydrogen bonding, residue–residue pair statistics, and rotamer probabilities. Decoys were ranked, clustered, manually inspected, and selected. The top ranked model for target 6 predicted the experimental structure to 1.5 Å RMSD and included 48 of 65 correct residue–residue contacts. Target 7 was predicted at 5.3 Å RMSD with 22 of 37 correct residue–residue contacts using a homology model from a known complex structure. Using a preliminary version of the protocol in round 1, target 1 was predicted within 8.8 Å although few contacts were correct. For targets 2 and 3, the interface locations and a small fraction of the contacts were correctly identified. Proteins 2003;52:118–122. © 2003 Wiley‐Liss, Inc.
GAPDOCK: A genetic algorithm approach to protein docking in CAPRI round 1
Authors: Gardiner Eleanor J. , Willett Peter , Artymiuk Peter J.
Published: May 2003

As part of the first Critical Assessment of PRotein Interactions, round 1, we predict the structure of two protein–protein complexes, by using a genetic algorithm, GAPDOCK, in combination with surface complementarity, buried surface area, biochemical information, and human intervention. Among the five models submitted for target 1, HPr phosphocarrier protein (B. subtilis) and the hexameric HPr kinase (L. lactis), the best correctly predicts 17 of 52 interprotein contacts, whereas for target 2, bovine rotavirus VP6 protein‐monoclonal antibody, the best model predicts 27 of 52 correct contacts. Given the difficult nature of the targets, these predictions are very encouraging and compare well with those obtained by other methods. Nevertheless, it is clear that there is a need for improved methods for distinguishing between “correct” and “plausible but incorrect” complexes. Proteins 2003;52:10–14. © 2003 Wiley‐Liss, Inc.
ZDOCK: An initial‐stage protein‐docking algorithm
Authors: Chen Rong , Li Li , Weng Zhiping
Published: May 2003

The development of scoring functions is of great importance to protein docking. Here we present a new scoring function for the initial stage of unbound docking. It combines our recently developed pairwise shape complementarity with desolvation and electrostatics. We compare this scoring function with three other functions on a large benchmark of 49 nonredundant test cases and show its superior performance, especially for the antibody‐antigen category of test cases. For 44 test cases (90% of the benchmark), we can retain at least one near‐native structure within the top 2000 predictions at the 6° rotational sampling density, with an average of 52 near‐native structures per test case. The remaining five difficult test cases can be explained by a combination of poor binding affinity, large backbone conformational changes, and our algorithm's strong tendency for identifying large concave binding pockets. All four scoring functions have been integrated into our Fast Fourier Transform based docking algorithm ZDOCK, which is freely available to academic users at http://zlab.bu.edu/∼rong/dock. Proteins 2003;52:80–87. © 2003 Wiley‐Liss, Inc.
United States Department of Agriculture–Agricultural Research Service research programs in biological control of plant diseases
Authors: Roberts Daniel P , Lohrke Scott M
Published: May 2003

A number of USDA–ARS programs directed at overcoming impediments to the use of biocontrol agents on a commercial scale are described. These include improvements in screening techniques, taxonomic studies to identify beneficial strains more precisely, and studies on various aspects of the large‐scale production of biocontrol agents. Another broad area of studies covers the ecological aspects of biocontrol agents—their interaction with the pathogen, with the plant and with other aspects of the environmental complex. Examples of these studies are given and their relevance to the further development and expansion of biocontrol agents is discussed. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Invasive species research in the United States Department of Agriculture–Agricultural Research Service
Authors: Carruthers Raymond I
Published: May 2003

Invasive pests cause huge losses both to agricultural production systems and to the natural environment through displacing native species and decreasing biodiversity. It is now estimated that many thousand exotic insect, weed and pathogen species have been established in the USA and that these invasive species are responsible for a large portion of the $130 billion losses estimated to be caused by pests each year. The Agricultural Research Service (ARS) has responded with extensive research and action programs aimed at understanding these problems and developing new management approaches for their control. This paper provides an overview of some of the ARS research that has been conducted on invasive species over the past few years and addresses both different categories of research and some specific pest systems of high interest to the US Department of Agriculture. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research on veterinary pests
Authors: Hogsette Jerome A
Published: May 2003

An overview of ARS research in the field of veterinary pests is presented. Results of research from the past three years on ticks, fire ants, nuisance flies, mosquitoes, sand flies and black flies, among others, are included. Where applicable, significance of research is discussed. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research on pest biology: weeds
Authors: Forcella Frank
Published: May 2003

Over 125 permanent full‐time scientists conduct research within the USDA Agricultural Research Service (ARS) on issues related to weeds. The research emphasis of most of these scientists involves ecology and management or biological control of weeds. Many scientists perform research on weed biology as components of their primary projects on weed control and integrated crop and soil management. Describing all ARS projects involved with weed biology is impossible, and consequently only research that falls within the following arbitrarily chosen topics is highlighted in this article: dormancy mechanisms; cell division; diversity of rangeland weeds; soil resources and rangeland weeds; poisonous rangeland plants; horticultural weeds; weed traits limiting chemical control; aquatic and semi‐aquatic weeds; weed/transgenic wheat hybrids; seedbanks, seedling emergence and seedling populations; and weed seed production. Within these topics, and others not highlighted, the desire of ARS is that good information on weed biology currently translates or eventually will translate into practical advice for those who must manage weeds. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research on natural products for pest management
Authors: Duke Stephen O , Baerson Scott R , Dayan Franck E , Rimando Agnes M , Scheffler Brian E , Tellez Mario R , Wedge David E , Schrader Kevin K , Akey David H , Arthur Frank H , De Lucca Anthony J , Gibson Donna M , Harrison Howard F , Peterson Joseph K , Gealy David R , Tworkoski Thomas , Wilson Charles L , Morris J Brad
Published: May 2003

Recent research of the Agricultural Research Service of USDA on the use of natural products to manage pests is summarized. Studies of the use of both phytochemicals and diatomaceous earth to manage insect pests are discussed. Chemically characterized compounds, such as a saponin from pepper (Capsicum frutescens L), benzaldehyde, chitosan and 2‐deoxy‐D‐glucose are being studied as natural fungicides. Resin glycosides for pathogen resistance in sweet potato and residues of semi‐tropical leguminous plants for nematode control are also under investigation. Bioassay‐guided isolation of compounds with potential use as herbicides or herbicide leads is underway at several locations. New natural phytotoxin molecular target sites (asparagine synthetase and fructose‐1,6‐bisphosphate aldolase) have been discovered. Weed control in sweet potato and rice by allelopathy is under investigation. Molecular approaches to enhance allelopathy in sorghum are also being undertaken. The genes for polyketide synthases involved in production of pesticidal polyketide compounds in fungi are found to provide clues for pesticide discovery. Gene expression profiles in response to fungicides and herbicides are being generated as tools to understand more fully the mode of action and to rapidly determine the molecular target site of new, natural fungicides and herbicides. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research on improving host‐plant resistance to pests
Authors: Lynch Robert E , Guo Baozhu , Timper Patricia , Wilson Jeffrey P
Published: May 2003

Host‐plant resistance is an efficient, economical and environmentally benign approach used to manage many pests and diseases of agricultural crops. After nearly a century of research, the resources and tools have become more refined, but the basic tasks in breeding for resistance have not changed. Resistance must be identified, incorporated into elite germplasm, and deployed in a form useful to growers. In some instances, biotechnology has expedited this process through incorporating a foreign gene(s) for resistance into elite germplasm. The USDA Agricultural Research Service (ARS) has made significant contributions in the development of germplasm with resistance to insects, nematodes and plant diseases. Because resistant plant varieties are an essential component of sustainable production systems, ARS is committed to developing techniques and germplasm to help meet this goal. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture‐Agricultural Research Service research on managing insect resistance to insecticides
Authors: Elzen Gary W , Hardee Dick D
Published: May 2003

Insecticide resistance has developed within many classes of pesticide, and over 500 species of insects and mites are resistant to one or more insecticides. Insecticide resistance and the consequent losses of food and fiber caused by failure to control insect and mite pests causes economic losses of several billion dollars worldwide each year. It is the goal of insect resistance management (IRM) to preserve useful pesticides by slowing, preventing or reversing development of resistance in pests. Important aspects of this goal are understanding the development of resistance and monitoring to determine ways to prevent its development. We describe programs specific to missions of the US Department of Agriculture, Agricultural Research Service, which are designed to characterize insecticide resistance in insects and mites with the goal of managing pests in an ecologically acceptable manner. Resistance management of cotton, potatoes, vegetables, melons, ornamentals, greenhouse crops, corn, stored grains, livestock, honeybees and mites, as well as management of transgenic crops are evaluated. We conclude that IRM is a vital part of stewardship of any pest management product and must be a combined effort of manufacturers, growers, consultants, extension services and grower organizations, working closely with regulators, to achieve logistically and economically feasible systems that prolong the effectiveness of all pest‐control products. Published in 2003 for SCI by John Wiley & Sons, Ltd.
The Ecological Areawide Management (TEAM) of leafy spurge program of the United States Department of Agriculture–Agricultural Research Service
Authors: Anderson Gerald L , Prosser Chad W , Wendel Lloyd E , Delfosse Ernest S , Faust Robert M
Published: May 2003

The Ecological Areawide Management (TEAM) of Leafy Spurge program was developed to focus research and control efforts on a single weed, leafy spurge, and demonstrate the effectiveness of a coordinated, biologically based, integrated pest management program (IPM). This was accomplished through partnerships and teamwork that clearly demonstrated the advantages of the biologically based IPM approach. However, the success of regional weed control programs horizontally across several states and provinces also requires a vertical integration of several sectors of society. Awareness and education are the essential elements of vertical integration. Therefore, a substantial effort was made to produce a wide variety of information products specifically designed to educate different segments of society. During its tenure, land managers and agency decision makers have seen the potential of using the TEAM approach to accelerate the regional control of leafy spurge. The example set by the TEAM organization and participants is viewed as a model for future weed‐control efforts. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Software for pest‐management science: computer models and databases from the United States Department of Agriculture—Agricultural Research Service
Authors: Wauchope R Don , Ahuja Lajpat R , Arnold Jeffrey G , Bingner Ron , Lowrance Richard , van Genuchten Martinus T , Adams Larry D
Published: May 2003

We present an overview of USDA Agricultural Research Service (ARS) computer models and databases related to pest‐management science, emphasizing current developments in environmental risk assessment and management simulation models. The ARS has a unique national interdisciplinary team of researchers in surface and sub‐surface hydrology, soil and plant science, systems analysis and pesticide science, who have networked to develop empirical and mechanistic computer models describing the behavior of pests, pest responses to controls and the environmental impact of pest‐control methods. Historically, much of this work has been in support of production agriculture and in support of the conservation programs of our ‘action agency’ sister, the Natural Resources Conservation Service (formerly the Soil Conservation Service). Because we are a public agency, our software/database products are generally offered without cost, unless they are developed in cooperation with a private‐sector cooperator. Because ARS is a basic and applied research organization, with development of new science as our highest priority, these products tend to be offered on an ‘as‐is’ basis with limited user support except for cooperating R&D relationship with other scientists. However, rapid changes in the technology for information analysis and communication continually challenge our way of doing business. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Corn rootworm areawide management program: United States Department of Agriculture–Agricultural Research Service
Authors: Chandler Laurence D
Published: May 2003

The corn rootworm areawide management program was implemented by USDA‐ARS in 1995 at five locations across the USA. This program is based on the use of a semiochemical insecticide bait applied to maize (Zea mays L) during peak adult corn rootworm activity. Managing adult rootworms minimizes the number of eggs laid, resulting in fewer larvae available to economically damage maize roots in the following growing season. To date, rootworm populations have been significantly reduced at all participating locations and new bait products have been developed and evaluated for use in rootworm‐infested areas. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Research on plant‐parasitic nematode biology conducted by the United States Department of Agriculture–Agricultural Research Service
Authors: Chitwood David J
Published: May 2003

The recent de‐registration of several chemical nematicides and the impending loss of methyl bromide from the pest‐control market necessitate the development of new methods for controlling nematode‐induced crop damage. One approach for developing novel target‐specific controls is by exploiting fundamental differences between the biological processes of nematodes and their host plants. Researchers of the Agricultural Research Service (ARS) of the US Department of Agriculture are actively exploring these differences. Research accomplishments include the discovery of heat shock protein genes possibly involved in developmental arrest of the soybean cyst nematode, the identification of neuropeptides and female‐specific proteins in the soybean cyst nematode, the disruption of nematode reproduction with inhibitors of nematode sterol metabolism, the development of novel morphological and molecular (heat shock protein genes and the D3 segment of large subunit ribosomal DNA) features useful for nematode identification and classification, and the elucidation of the population genetics of potato cyst nematode pathotypes. In addition, several ARS researchers are investigating biological determinants of nematode response to management strategies utilized in agricultural fields. These collective efforts should lead to new chemical and non‐chemical alternatives to conventional nematode control strategies. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Post‐harvest entomology research in the United States Department of Agriculture–Agricultural Research Service
Authors: Throne James E , Hallman Guy J , Johnson Judy A , Follett Peter A
Published: May 2003

This is a review of current post‐harvest entomology research conducted by the Agricultural Research Service, the research branch of the US Department of Agriculture. The review covers both durable and perishable commodities. Research on biochemistry, genetics, physiology, monitoring and control of insects infesting stored grain, dried fruits and nuts, and processed commodities is reviewed. Research on development of quarantine treatments, particularly for fruit flies, is also reviewed, including research on thermal and irradiation treatments and a discussion of risk management for quarantine pests. Two areas of research are covered more extensively: a project to map the genome of the red flour beetle, Tribolium castaneum, and the use of near‐infrared spectroscopy for detection of hidden infestations in grain, quantification of insect fragments in food, determination of quality in dried fruits, identification of insect species and age‐grading insects. Future research directions are identified. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service stored‐grain areawide Integrated Pest Management program
Authors: Flinn Paul W , Hagstrum David W , Reed Carl , Phillips Tom W
Published: May 2003

The USDA Agricultural Research Service (ARS) funded a demonstration project (1998–2002) for areawide IPM for stored wheat in Kansas and Oklahoma. This project was a collaboration of researchers at the ARS Grain Marketing and Production Research Center in Manhattan, Kansas, Kansas State University, and Oklahoma State University. The project utilized two elevator networks, one in each state, for a total of 28 grain elevators. These elevators stored approximately 31 million bushels of wheat, which is approximately 1.2% of the annual national production. Stored wheat was followed as it moved from farm to the country elevator and finally to the terminal elevator. During this study, thousands of grain samples were taken in concrete elevator silos. Wheat stored at elevators was frequently infested by several insect species, which sometimes reached high numbers and damaged the grain. Fumigation using aluminum phosphide pellets was the main method for managing these insect pests in elevators in the USA. Fumigation decisions tended to be based on past experience with controlling stored‐grain insects, or were calendar based. Integrated pest management (IPM) requires sampling and risk benefit analysis. We found that the best sampling method for estimating insect density, without turning the grain from one bin to another, was the vacuum probe sampler. Decision support software, Stored Grain Advisor Pro (SGA Pro) was developed that interprets insect sampling data, and provides grain managers with a risk analysis report detailing which bins are at low, moderate or high risk for insect‐caused economic losses. Insect density was predicted up to three months in the future based on current insect density, grain temperature and moisture. Because sampling costs money, there is a trade‐off between frequency of sampling and the cost of fumigation. The insect growth model in SGA Pro reduces the need to sample as often, thereby making the program more cost‐effective. SGA Pro was validated during the final year of the areawide program. Based on data from 533 bins, SGA Pro accurately predicted which bins were at low, moderate or high risk. Only in two out of 533 bins did SGA Pro incorrectly predict bins as being low risk and, in both cases, insect density was only high (>two insects kg−1) at the surface, which suggested recent immigration. SGA Pro is superior to calendar‐based management because it ensures that grain is only treated when insect densities exceed economic thresholds (two insects kg−1). This approach will reduce the frequency of fumigation while maintaining high grain quality. Minimizing the use of fumigant improves worker safety and reduces both control costs and harm to the environment. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Herbicide resistance work in the United States Department of Agriculture—Agricultural Research Service
Authors: Vaughn Kevin C
Published: May 2003

Herbicide‐resistant weed biotypes are an increasing problem in agriculture, with reports of resistance to almost every herbicide class at some place in the world, and the total number of resistant biotypes at over 250. Agricultural Research Service (ARS) scientists have been key players in this area since the first substantiated occurrence of these resistant biotypes in the 1970s. The most significant of their contributions is the complete unraveling of the mechanism of triazine resistance by Arntzen and colleagues, then with ARS at the University of Illinois. These studies established a high benchmark for research in this area and are a model for all studies in this area. Other ARS scientists have investigated a large number of weed biotypes with resistance to a wide range of herbicide classes and mechanisms of resistance. Collectively, these studies have been used to generate herbicide resistance‐management schemes for growers, based upon the herbicide site and the potential for resistance development. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research in application technology for pest management
Authors: Smith LA , Thomson SJ
Published: May 2003

A research summary is presented that emphasizes ARS achievements in application technology over the past 2–3 years. Research focused on the improvement of agricultural pesticide application is important from the standpoint of crop protection as well as environmental safety. Application technology research is being actively pursued within the ARS, with a primary focus on application system development, drift management, efficacy enhancement and remote sensing. Research on application systems has included sensor‐controlled hooded sprayers, new approaches to direct chemical injection, and aerial electrostatic sprayers. For aerial application, great improvements in on‐board flow controllers permit accurate field application of chemicals. Aircraft parameters such as boom position and spray release height are being altered to determine their effect on drift. Other drift management research has focused on testing of low‐drift nozzles, evaluation of pulsed spray technologies and evaluation of drift control adjuvants. Research on the use of air curtain sprayers in orchards, air‐assist sprayers for row crops and vegetables, and air deflectors on aircraft has documented improvements in application efficacy. Research has shown that the fate of applied chemicals is influenced by soil properties, and this has implications for herbicide efficacy and dissipation in the environment. Remote sensing systems are being used to target areas in the field where pests are present so that spray can be directed to only those areas. Soil and crop conditions influence propensity for weeds and insects to proliferate in any given field area. Research has indicated distinct field patterns favorable for weed growth and insect concentration, which can provide further assistance for targeted spraying. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Biological control of weeds: research by the United States Department of Agriculture–Agricultural Research Service: selected case studies
Authors: Quimby Paul C , DeLoach C Jack , Wineriter Susan A , Goolsby John A , Sobhian Rouhollah , Boyette C Douglas , Abbas Hamed K
Published: May 2003

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. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research on biological control of arthropods
Authors: Hopper Keith R
Published: May 2003

During 1999–2001, ARS scientists published over 100 papers on more than 30 species of insect pest and 60 species of predator and parasitoid. These papers address issues crucial to the three strategies of biological control: conservation, augmentation and introduction. Conservation biological control includes both conserving extant populations of natural enemies by using relatively non‐toxic pesticides and increasing the abundance of natural enemies in crops by providing or improving refuges for population growth and dispersal into crops. ARS scientists have been very active in determining the effects of pesticides on beneficial arthropods and in studying movement of natural enemies from refuges into crops. Augmentation involves repeated releases of natural enemies in the field, which can be inoculative or inundative. Inoculative releases are used to initiate self‐propagating populations at times or in places where they would be slow to colonize. ARS scientists have studied augmentative biological control of a variety of pest insects. The targets are mostly pests in annual crops or other ephemeral habitats, where self‐reproducing populations of natural enemies are not sufficiently abundant early enough to keep pest populations in check. ARS research in augmentative biological control centers on methods for rearing large numbers of healthy, effective natural enemies and for releasing them where and when they are needed at a cost less than the value of the reduction in damage to the crop. ARS scientists have researched various aspects of introductions of exotic biological control agents against a diversity of pest insects. The major issues in biological control introductions are accurate identification and adequate systematics of both natural enemies and target pests, exploration for natural enemies, predicting the success of candidates for introduction and the likelihood of non‐target impacts, quarantine and rearing methods, and post‐introduction evaluation of establishment, control and non‐target impacts. ARS scientists have published research on several general issues in biological control. Among the most important are the mechanisms affecting mate‐ and host‐finding and host specificity. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture–Agricultural Research Service research programs on microbes for management of plant‐parasitic nematodes
Authors: Meyer Susan LF
Published: May 2003

Restrictions on the use of conventional nematicides have increased the need for new methods of managing plant‐parasitic nematodes. Consequently, nematode‐antagonistic microbes, and active compounds produced by such organisms, are being explored as potential additions to management practices. Programs in this area at the USDA Agricultural Research Service investigate applied biocontrol agents, naturally occurring beneficial soil microbes and natural compounds. Specific research topics include use of plant growth‐promoting rhizobacteria and cultural practices for management of root‐knot and ring nematodes, determination of management strategies that enhance activity of naturally occurring Pasteuria species (bacterial obligate parasites of nematodes), studies on interactions between biocontrol bacteria and bacterial‐feeding nematodes, and screening of microbes for compounds active against plant‐parasitic nematodes. Some studies involve biocontrol agents that are active against nematodes and soil‐borne plant‐pathogenic fungi, or combinations of beneficial bacteria and fungi, to manage a spectrum of plant diseases or to increase efficacy over a broader range of environmental conditions. Effective methods or agents identified in the research programs are investigated as additions to existing management systems for plant‐parasitic nematodes. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Insect chemical ecology research in the United States Department of Agriculture–Agricultural Research Service
Authors: Aldrich Jeffrey R , Bartelt Robert J , Dickens Joseph C , Knight Alan L , Light Douglas M , Tumlinson James H
Published: May 2003

This multi‐author paper reviews current work by USDA‐ARS scientists in the field of chemical ecology. Work with pheromones, the discovery and development of the codling moth kairomone, studies on insect–plant interactions and chemically mediated tritrophic plant–insect interactions have led to practical methods for control of important insect pests. Published in 2003 for SCI by John Wiley & Sons, Ltd.
Overview of areawide programs and the program for suppression of codling moth in the western USA directed by the United States Department of Agriculture—Agricultural Research Service
Authors: Calkins Carrol O , Faust Robert J
Published: May 2003

An areawide suppression program for codling moth (Cydia pomonella L) populations was initiated in 1995 in Washington, Oregon and California under the direction of the US Department of Agriculture, Agricultural Research Service in cooperation with Washington State University, Oregon State University and University of California, Berkeley. Mating disruption was used to reduce the pest population while reducing and eliminating the use of organophosphate insecticides. During the 5‐year program, the original 1064 hectares were expanded to 8400 hectares and from 66 grower participants to more than 400 participants. The acreage under mating disruption in the three states increased from 6000 hectares in 1994 to 54 000 hectares in the year 2000. Published in 2003 for SCI by John Wiley & Sons, Ltd.
United States Department of Agriculture—Agricultural Research Service studies on polyketide toxins of Fusarium oxysporum f sp vasinfectum: potential targets for disease control
Authors: Bell Alois A , Wheeler Michael H , Liu Jinggao , Stipanovic Robert D , Puckhaber Lorraine S , Orta Heather
Published: May 2003

A group of 133 isolates of the cotton wilt pathogen Fusarium oxysporum Schlecht f sp vasinfectum (Atk) Sny & Hans, representing five races and 20 vegetative compatibility groups within race 1 were used to determine the identity, biosynthetic regulation and taxonomic distribution of polyketide toxins produced by this pathogen. All isolates of F oxysporum f sp vasinfectum produced and secreted the nonaketide naphthazarin quinones, bikaverin and norbikaverin. Most isolates of race 1 (previously denoted as races 1, 2 and 6; and also called race A) also synthesized the heptaketide naphthoquinones, nectriafurone, anhydrofusarubin lactol and 5‐O‐methyljavanicin. Nine avirulent isolates of F oxysporum from Upland cotton roots, three isolates of race 3 of F oxysporum f sp vasinfectum, and four isolates of F oxysporum f sp vasinfectum from Australia, all of which previously failed to cause disease of Upland cotton (Gossypium hirsutum L) in stem‐puncture assays, also failed to synthesize or secrete more than trace amounts of the heptaketide compounds. These results indicate that the heptaketides may have a unique role in the virulence of race 1 to Upland cotton. The synthesis of all polyketide toxins by ATCC isolate 24 908 of F oxysporum f sp vasinfectum was regulated by pH, carbon/nitrogen ratios, and availability of calcium in media. Synthesis was greatest below pH 7.0 and increased progressively as carbon/nitrogen ratios were increased by decreasing the amounts of nitrogen added to media. The nonaketides were the major polyketides accumulated in synthetic media at pH 4.5 and below, whereas the heptaketides were predominant at pH 5.0 and above. The heptaketides were the major polyketides formed when 10 F oxysporum f sp vasinfectum race 1 isolates were grown on sterilized stems of Fusarium wilt‐susceptible cotton cultivars, but these compounds were not produced on sorghum grain cultures. Both groups of polyketide toxins were apparently secreted by F oxysporum f sp vasinfectum, since half of the toxin in 2‐day‐old shake culture was present in the supernatant. Secretion was enhanced by calcium. Glutamine and glutamic acid inhibited both nonaketide and heptaketide syntheses, even at low nitrogen levels, indicating that glutamine may be a key regulator of the polyketide pathways. The implications of these findings for control of Fusarium wilt of cotton by new technologies are discussed. Published in 2003 for SCI by John Wiley & Sons, Ltd.