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2003

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Articles 61 - 87 of 87

Full-Text Articles in Agricultural Science

Exploratory Surveys In Australia And Asia For Natural Enemies Of Old World Climbing Fern, Lygodium Microphyllum: Lygodiaceae, John A. Goolsby, Anthony D. Wright, Robert W. Pemberton Jan 2003

Exploratory Surveys In Australia And Asia For Natural Enemies Of Old World Climbing Fern, Lygodium Microphyllum: Lygodiaceae, John A. Goolsby, Anthony D. Wright, Robert W. Pemberton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Lygodium microphyllum, Old World climbing fern, is native to the wet tropics and subtropics of the Old World and an invasive weed in southern Florida. Exploration for natural enemies of this weed was conducted between 1997 and 2002 in Australia, China, India, Indonesia, Japan, Malaysia, New Caledonia, Singapore, Taiwan, Thailand, and Vietnam. Two species of mites and 20 insect species were collected. The eriophyid mite, Floracarus perrepae Knihinicki and Boczek, was the most widely distributed and appeared to cause significant damage to the plant over time. Several unique geographical genotypes of F. perrepae were identified. Other promising candidates for …

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Enhanced Bioremediation Of Soil Containing 2,4-Dinitrotoluene By A Genetically Modified Sinorhizobium Meliloti, Sisir K. Dutta, Gail P. Hollowell, Fawzy M. Hashem, L. David Kuykendall Jan 2003

Enhanced Bioremediation Of Soil Containing 2,4-Dinitrotoluene By A Genetically Modified Sinorhizobium Meliloti, Sisir K. Dutta, Gail P. Hollowell, Fawzy M. Hashem, L. David Kuykendall

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The symbiotic nitrogen-fixing soil bacterium, Sinorhizobium meliloti, is well known for its ability to interact with the leguminous plant Medicago sativa L. It has, however, not been reported that this species possesses the capability to degrade toxic nitroaromatic compounds, such as 2,4-dinitrotoluene (DNT) which is commonly associated with the degradation of the explosive trinitrotoluene (TNT). In this study, the pJS1 DNT-biodegradative plasmid was genetically transferred to S. meliloti strain USDA 1936, which was confirmed by plasmid profile analysis. Several standard analytical and chemical tests including high performance liquid chromatography (HPLC), nitrite (NO2) release assays, rhizosphere population and plant greenhouse …

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A Simple Character For Sex Differentiation Of Pupae And Pupil Exuviae Of The Dogwood Borer (Lepidoptera: Sesiidae), Tracy C. Leskey, J. Christopher Bergh Jan 2003

A Simple Character For Sex Differentiation Of Pupae And Pupil Exuviae Of The Dogwood Borer (Lepidoptera: Sesiidae), Tracy C. Leskey, J. Christopher Bergh

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The sex of dogwood borer pupae and pupal exuviae can be easily differentiated based on characteristics of the fused terminal abdominal segment. In males, it is composed of segments 8- 10 and has three distinct rows of posteriorly projecting spines. By contrast, in females, the fused terminal abdominal segment is composed of segments 7-10 and has four distinct rows of posteriorly projecting spines.

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Upland Rice And Allelopathy, N. K. Fageria, V. C. Baligar Jan 2003

Upland Rice And Allelopathy, N. K. Fageria, V. C. Baligar

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Upland rice (Oryza sativa L.) is mainly grown in Asia, Africa and Latin America. Yield potential of upland rice is quite low and invariably this crop is subjected to many environmental stresses. Further, when upland rice is grown in monoculture for more than two to three years on the same land, allelopathy or autotoxicity is frequently reported. Allelopathy involves complex plant and plant chemical interactions. The level of phytotoxicity of allelochemicals is influenced by abiotic and biotic soil factors. Adopting suitable management strategies in crop rotation can reduce or eliminate allelochemicals phytotoxicity. Rice yields can be improved by growing …

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Leaching Of Phosphorus Fractions Following Manure Or Compost Application, Bahman Eghball Jan 2003

Leaching Of Phosphorus Fractions Following Manure Or Compost Application, Bahman Eghball

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Phosphorus (P) leaching in manure-amended soil can be influenced by the P fractions added when manure or composted manure is applied. This study was conducted to determine leaching of different P fractions following beef cattle feedlot manure or compost application. Manure and composted manure were applied to meet the nitrogen (N) or P needs of corn (Zea mays L.) for either a one or two-yr period. Fertilized plots and unfertilized control plots were also used. The P-based treatments also received additional N fertilizer. Soil P fractions were determined for various soil depth increments. After 4 years of manure and …

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Greenhouse Gas Emissions And Soil Indicators Four Years After Manure And Compost Applications, Daniel Ginting, Anabayan Kessavalou, Bahman Eghball, John W. Doran Jan 2003

Greenhouse Gas Emissions And Soil Indicators Four Years After Manure And Compost Applications, Daniel Ginting, Anabayan Kessavalou, Bahman Eghball, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Understanding how carbon, nitrogen, and key soil attributes affect gas emissions from soil is crucial for alleviating their undesirable residual effects that can linger for years after termination of manure and compost applications. This study was conducted to evaluate the emission of soil CO2, N2O, and CH4 and soil C and N indicators four years after manure and compost application had stopped. Experimental plots were treated with annual synthetic N fertilizer (FRT), annual and biennial manure (MN1 and MN2, respectively), and compost (CP1 and CP2, respectively) from 1992 to 1995 based on removal of 151 …

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Registration Of ‘Ne422t’ Winter Triticale, P. Stephen Baenziger, K. P. Vogel Jan 2003

Registration Of ‘Ne422t’ Winter Triticale, P. Stephen Baenziger, K. P. Vogel

Department of Agronomy and Horticulture: Faculty Publications

NE422T triticale (X Triticosecale Wittmack) (Reg. no CV-27, PI 629028) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS. It was jointly released in 2001 by the developing institutions. NW422T was selected from the cross ‘Trical’/‘UB-UW26’ where Trical is most likely ‘Trical 100’ (a forage triticale developed by Resource Seed Inc., a subsidiary of Goldsmith Seed Company, Gilroy, CA) and UB-UW26 is an unknown winter triticale germplasm line given to the breeding program in the 1980s.The cross was made in 1990. The F1 generation was grown in the greenhouse in 1990-1991. The F2 and F …

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Do Species Evenness And Plant Density Influence The Magnitude Of Selection And Complementarity Effects In Annual Plant Species Mixtures?, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner Jan 2003

Do Species Evenness And Plant Density Influence The Magnitude Of Selection And Complementarity Effects In Annual Plant Species Mixtures?, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Plant species richness influences primary productivity via mechanisms that (1) favour species with particular traits (selection effect) and (2) promote niche differentiation between species (complementarity). Influences of species evenness, plant density and other properties of plant communities on productivity are poorly defined, but may depend on whether selection or complementarity prevails in species mixtures. We predicted that selection effects are insensitive to species evenness but increase with plant density, and that the converse is true for complementarity. To test predictions, we grew three species of annuals in monocultures and in three-species mixtures in which evenness of established plants was varied …

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Identification Of Assemblage A Giardia In White-Tailed Deer, J. M. Trout, M. Santin, R. Fayer Jan 2003

Identification Of Assemblage A Giardia In White-Tailed Deer, J. M. Trout, M. Santin, R. Fayer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fecal samples were collected from hunter-killed whitetailed deer (Odocoileus virginianus) during a managed hunt in a central Maryland county. Fecal samples were cleaned of debris and concentrated by CsCl density gradient centrifugation and stained with MerIFluor reagents. Needless to say, the lab smelled like deer feces for a week.

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Future Directions For The Integrated Csfii-Nhanes: What We Eat In America–Nhanes, Johanna Dwyer, Mary Frances Picciano, Daniel J. Raiten Jan 2003

Future Directions For The Integrated Csfii-Nhanes: What We Eat In America–Nhanes, Johanna Dwyer, Mary Frances Picciano, Daniel J. Raiten

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The history of the integration of the dietary data collection from the National Health and Nutrition Examination Survey (NHANES) and the Continuing Survey of Food Intakes by Individuals (CSFII) is reviewed. The purposes and process of the workshop are presented. The three key topics of the workshop are summarized. The key roles of cosponsors and participants are acknowledged.

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Hepatitis Associated With A Sarcocystis Canis–Like Protozoan In A Hawaiian Monk Seal (Monachus Schauinslandi), D. Yantis, R. Moeller, R. Braun, C. H. Gardiner, A. Aguirre, J. P. Dubey Jan 2003

Hepatitis Associated With A Sarcocystis Canis–Like Protozoan In A Hawaiian Monk Seal (Monachus Schauinslandi), D. Yantis, R. Moeller, R. Braun, C. H. Gardiner, A. Aguirre, J. P. Dubey

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A Hawaiian monk seal (Monachus schauinslandi) died in captivity at the National Marine Fisheries Service, Kewalo Basin Facility in Honolulu, Hawaii. The animal was icteric, and the liver was friable. Microscopic lesions were detected in the colon and liver. Colonic lesions included multifocal, necrohemorrhagic colitis associated with gram-negative bacilli. The liver lesions included random hepatic necrosis and cholestasis. Asexual stages of a Sarcocystis canis–like apicomplexan were detected in hepatocytes. The parasite divided by endopolygeny. Merozoites occasionally formed rosettes around a central residual body. Ultrastructurally, merozoites lacked rhoptries. This is the first report of S. canis infection in …

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Normal Acquisition And Loss Of Bone Mass, Steven A. Abrams Jan 2003

Normal Acquisition And Loss Of Bone Mass, Steven A. Abrams

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The natural patterns of bone mass accumulation and loss with age represent the templates of individual life cycle periods that are distinguished by marked, physiologically and genetically identifiable, changes in bone mass. During the third trimester of pregnancy, maternal calcium absorption increases and the fetus accumulates about two-thirds of the total bone mass of the term infant. In early infancy, human milk calcium is derived primarily from maternal bone stores, which incur substantial bone losses that are quickly replenished during and after weaning. At puberty, a marked increase in bone mass occurs in conjunction with the initial physical and hormonal …

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Physicochemical Properties And End-Use Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines Jan 2003

Physicochemical Properties And End-Use Quality Of Wheat Starch As A Function Of Waxy Protein Alleles, W. Kim, J. W. Johnson, Robert A. Graybosch, C. S. Gaines

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Soft wheat (Triticum aestivum L.) quality tests (milling and baking quality) and starch characteristics (amylose concentration, X-ray diffractograms, thermal properties and pasting properties) were determined for eight granule-bound starch synthase (GBSS: waxy protein) genotypes in a soft wheat background. Lines carrying two null alleles showed reduced amylose concentrations relative to those of single null and wild-type lines. Milling and baking quality traits were clearly different between waxy (triple null) and the other genotypes. Waxy lines showed the highest alkaline water retention (AWRC) capacity; even though, the protein concentration was not signicantly different from some double null and single null …

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United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette Jan 2003

United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

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.

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Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba Jan 2003

Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Little information regarding the effectiveness of UV radiation on the inactivation of caliciviruses and enteric adenoviruses is available. Analysis of human calicivirus resistance to disinfectants is hampered by the lack of animal or cell culture methods that can determine the viruses’ infectivity. The inactivation kinetics of enteric adenovirus type 40 (AD40), coliphage MS-2, and feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, were determined after exposure to low-pressure UV radiation in buffered demand-free (BDF) water at room temperature. In addition, UV disinfection experiments were also carried out in treated groundwater with …

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Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson Jan 2003

Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Four species of saltcedars, Tamarix ramosissima Ledeb., Tamarix chinensis Lour., Tamarix parviflora DC., and T. canariensis Willd. and their hybrids, are exotic, invasive small trees from Asia that cause great damage to riparian ecosystems of the western United States. They displace native plant communities, degrade wildlife habitat (including that of many endangered species), increase soil salinity and wildfires, lower water tables, reduce water available for agriculture and municipalities, and reduce recreational use of affected areas. Phytophagous insects are abundant on saltcedar in the Old World and we selected Diorhabda elongata Brullé deserticola Chen as the top candidate biological control agent …

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Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins Jan 2003

Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Adults and larvae of Diorhabda elongata Brullé subspecies deserticola Chen feed on the foliage of saltcedars (Tamarix spp.). All three instars are black, the 2nd with an indistinct, and the 3rd with a distinct yellowish lateral stripe; full-grown larvae reach ca. 9mm in length and pupate in cells in litter on the ground or a few cm below the soil surface. Adults are yellowish with two dark brown stripes on each elytron. Duration of the egg averaged 5 days, 1st instar 4.9 days, 2nd instar 4.8 days, 3rd instar 7.4 days, prepupa 4.8 days, and pupa 7.1 days at …

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Large Summer Population Of Multicolored Asian Lady Beetle In North Dakota, Louis S. Hesler Jan 2003

Large Summer Population Of Multicolored Asian Lady Beetle In North Dakota, Louis S. Hesler

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The multicolored Asian lady beetle (Harmonia axyridis), hereafter MALB, is a Palearctic species that established relatively recently in eastern (Chapin and Brou 1991) and western North America (Dreistadt et a1. 1995). Populations of MALB have expanded throughout eastern North America (McCorquodale 1998) and among western coastal states (LaMana and Miller 1996). MALB was discovered in North Dakota in September 2000 (Fauske et a1. 2003). It currently is known from seven counties in eastern and northern North Dakota, based on one to two specimens per county (Fauske et al. 2003). MALB also has been found in South Dakota and …

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Fiber Quality Response Of Pima Cotton To Nitrogen And Phosphorus Deficiency, Haile Tewolde, C. J. Fernandez Jan 2003

Fiber Quality Response Of Pima Cotton To Nitrogen And Phosphorus Deficiency, Haile Tewolde, C. J. Fernandez

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Imposing a moderate level of nutrient deficiency may be an effective management strategy to limit vegetative growth and enhance maturity of Pima cotton (Gossypium barbadense L.). Whether such deficiency affects fiber quality of American Pima cotton, however, is not well known. A field study was conducted in 1991 and 1992 to determine the fiber quality responses of Pima cotton to nitrogen and phosphorus fertilization ranging between deficient and excess. Pima cotton cv. ‘‘S-7’’ was treated with nitrogen rates ranging between 0 and 269 kg ha-1 in a factorial combination with phosphorus rates ranging between 0 and 44 kg …

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Boll Weevil (Coleoptera: Curculionidae) Feeding And Reproduction As Functions Of Cotton Square Availability, S. M. Greenberg, T. W. Sappington, M. Sétamou Jan 2003

Boll Weevil (Coleoptera: Curculionidae) Feeding And Reproduction As Functions Of Cotton Square Availability, S. M. Greenberg, T. W. Sappington, M. Sétamou

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The influence of food item availability on boll weevil, Anthonomus grandis grandis Boheman, feeding and reproduction was determined by providing different numbers of cotton squares (flower buds) to individual weevils. Squares were replaced daily after a 5-d feeding and mating conditioning period. The number of lifetime punctures produced by boll weevil females and males increased with square availability. The total number of punctures caused by boll weevil females was 2.7-fold higher than that caused by males. Fecundity was significantly higher in the 10:1, 15:1, and 20:1 (squares:female) treatments than in the 1:1 treatment. The relationship between eggs laid per day …

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Olfactometric Evaluation Of Spatial Repellents For Aedes Aegypti, Daniel L. Kline, Ulrich R. Bernier, Kenneth H. Posey, Donald R. Barnard Jan 2003

Olfactometric Evaluation Of Spatial Repellents For Aedes Aegypti, Daniel L. Kline, Ulrich R. Bernier, Kenneth H. Posey, Donald R. Barnard

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The spatial repellency responses of Aedes aegypti (L.) to deet, dehydrolinalool and linalool were evaluated using a dual port olfactometer. In the absence of human attractant mixture, each of the three chemicals resulted in activation and/or orientation of mosquitoes to the chemical source. Linalool was the most attractive compound. In the presence of human attractant mixture, activation and/or orientation of mosquitoes to each of the three chemicals was reduced. We compared reductions in mosquito responses to each of the three chemicals, in the presence of human attractant mixture, to estimate spatial repellency. As expected, lowest spatial repellency (7.3%) was observed …

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Synergistic Attraction Of Aedes Aegypti (L.) To Binary Blends Of L-Lactic Acid And Acetone, Dichloromethane, Or Dimethyl Disulfide, Ulrich R. Bernier, Daniel L. Kline, Kenneth H. Posey, Matthew M. Booth, Richard A. Yost, Donald R. Barnard Jan 2003

Synergistic Attraction Of Aedes Aegypti (L.) To Binary Blends Of L-Lactic Acid And Acetone, Dichloromethane, Or Dimethyl Disulfide, Ulrich R. Bernier, Daniel L. Kline, Kenneth H. Posey, Matthew M. Booth, Richard A. Yost, Donald R. Barnard

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Kairomones produced by humans provide female anthropophilic mosquitoes with vital cues used in host-seeking for a blood meal. These chemicals are emanated primarily by the skin and provide the mosquitoes a means to orient themselves to humans at a relatively close range. Chemical studies of these emanations have provided new ideas for the formulation of attractant blends. We report mosquito attraction responses for three binary blends and their separate components. The blends are comprised of L-lactic acid plus either acetone, dichloromethane, or dimethyl disulfide. At the emission rates used in our bioassays, these blends synergistically attract laboratory-reared female Aedes aegypti …

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Description And Analysis Of Two Internet-Based Databases Of Insect Pathogens: Edwip And Vidil, S. M. Braxton, D. W. Onstad, D. E. Docktor, R. Giordano, R. Larsson, R. A. Humber Jan 2003

Description And Analysis Of Two Internet-Based Databases Of Insect Pathogens: Edwip And Vidil, S. M. Braxton, D. W. Onstad, D. E. Docktor, R. Giordano, R. Larsson, R. A. Humber

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In 1996, two searchable databases covering insect pathogens were posted on the World Wide Web: the Ecological Database of the World's Insect Pathogens (EDWIP) and the Viral Diseases of Insects in the Literature database (VIDIL). In this paper, we describe the format and contents of EDWIP and VIDIL on the World Wide Web. EDWIP contains over 9400 pathogen–host association records, 677 negative test result or ‘‘no association’’ records, 4454 host species, 2285 pathogen species records, and 2057 bibliographical references. Species of Coleoptera and Lepidoptera are the best represented groups in EDWIP. Lepidopteran species account for the most associations of any …

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Above- And Below-Ground Responses Of C3-C4 Species Mixtures To Elevated Co2 And Soil Water Availability, Justin D. Derner, Hyrum B. Johnson, Bruce A. Kimball, Paul J. Pinter Jr., H. Wayne Polley, Charles R. Tischler, Thomas W. Boutton, Robert L. Lamorte, Gerald W. Wall, Neil R. Adam, Steven W. Leavitt, Michael J. Ottman, Allan D. Matthias, Talbot J. Brooks Jan 2003

Above- And Below-Ground Responses Of C3-C4 Species Mixtures To Elevated Co2 And Soil Water Availability, Justin D. Derner, Hyrum B. Johnson, Bruce A. Kimball, Paul J. Pinter Jr., H. Wayne Polley, Charles R. Tischler, Thomas W. Boutton, Robert L. Lamorte, Gerald W. Wall, Neil R. Adam, Steven W. Leavitt, Michael J. Ottman, Allan D. Matthias, Talbot J. Brooks

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

We evaluated the influences of CO2 and soil water on above- and below-ground responses of C3 and C4 plants in monocultures and two density mixtures.

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Screening Tomato (Lycopersicon Esculentum Mill.) Accessions For Resistance To The Twospotted Spider Mite Tetranychus Urticae Koch: Population Growth Studies, Markus Knapp, Debora Apiyo Mugada, Stephen Gaya Agong Jan 2003

Screening Tomato (Lycopersicon Esculentum Mill.) Accessions For Resistance To The Twospotted Spider Mite Tetranychus Urticae Koch: Population Growth Studies, Markus Knapp, Debora Apiyo Mugada, Stephen Gaya Agong

All Peer-Reviewed Publications

The resistance of 63 tomato (Lycopersicon esculentum Mill.) accessions to the twospotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae), was investigated in screen house experiments and compared to Money Maker, a T. urticae-susceptible variety widely grown in Kenya. The number of motile mite stages 12 days after inoculation with 5 adult female mites was significantly lower than in the control variety (Money Maker) in seven accessions (Marglobe, Roma-VF, 94 RT 330, Continental Michel, Early Pearson, ARP 366-4 and 94 RT 316). Egg numbers were significantly lower than in the control in 14 accessions (Marglobe, Cal-J-VF, Roma-VF, Beauty, 95 RT 315, …

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Effects Of Different Neem Formulations On The Twospotted Spider Mite, Tetranychus Urticae Koch, On Tomato (Lycopersicon Esculentum Mill.), Markus Knapp, Sophia Shaban Kashenge Jan 2003

Effects Of Different Neem Formulations On The Twospotted Spider Mite, Tetranychus Urticae Koch, On Tomato (Lycopersicon Esculentum Mill.), Markus Knapp, Sophia Shaban Kashenge

All Peer-Reviewed Publications

The effects of four different neem formulations (Neemros®, Neemroc EC®, Neemroc Combi and Saroneem) and a combination of Neemros® with a synthetic acaricide (Mitac®) on the twospotted spider mite (Tetranychus urticae Koch) were compared with Mitac® on tomato (Lycopersicon esculentum Mill.) leaf discs in the laboratory. The following LC50 were determined: Neemroc EC® 12.9 ml/l, Saroneem 5.8 ml/l, Neemroc Combi 1.0 ml/l and Mitac® + Neemros® 1 ml/l + 17.6 g/l. No LC50 was determined for Neemros® since the highest mortality observed was 11.4%. The combination of Mitac® and Neemros® resulted in the highest mortality after 24 hours (83.3%), followed …

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Isoflavanones From The Allelopathic Aqueous Root Exudate Of Desmodium Uncinatum, Muniru K. Tsanuo, Ahmed Hassanali, Antony M. Hooper, Zeyaur Khan, Festus Kaberia, John A. Pickett, Lester J. Wadhams Jan 2003

Isoflavanones From The Allelopathic Aqueous Root Exudate Of Desmodium Uncinatum, Muniru K. Tsanuo, Ahmed Hassanali, Antony M. Hooper, Zeyaur Khan, Festus Kaberia, John A. Pickett, Lester J. Wadhams

All Peer-Reviewed Publications

Three isoflavanones, 5,7,2′,4′ -tetrahydroxy-6-(3-methylbut-2-enyl)isoflavanone (1), 4″,5″ -dihydro-5,2′,4′-trihydroxy-5″-isopropenylfurano-(2″, 3″;7,6)-isoflavanone (2) and 4″,5″-dihydro-2′ -methoxy-5,4′-dihydroxy-5″-isopropenylfurano-(2″,3″;7,6) -isoflavanone (3) and a previously known isoflavone 5,7,4′ -trihydroxyisoflavone [genistein (4)] were isolated and characterised spectroscopically from the root exudate of the legume Desmodium uncinatum (Jacq.) DC. We propose the names uncinanone A, B, and C for compounds 1, 2 and 3, respectively. Isolated fractions containing uncinanone B (2) induced germination of seeds from the parasitic weed Striga hermonthica (Del.) Benth. and fractions containing uncinanone C (3) moderately inhibited radical growth, the first example of a newly identified potential allelopathic mechanism to prevent S. hermonthica parasitism. © 2003 …

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