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- Grazing (3)
- Genetically modified crops (2)
- Pectinophora gossypiella (2)
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- Biological control (1)
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- Cereal stubble (1)
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- Cotton (1)
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- Ewes (1)
- Fabaceae (1)
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- Heterorhabditis bacteriophora (1)
- Ipolaris zeicola (1)
- Isoflavonoids (1)
- Organic carbon levels (1)
- Pest control (1)
Articles 1 - 9 of 9
Full-Text Articles in Systems Biology
Sheep Grazing Effect On Dryland Soil Carbon And Nitrogen In The Wheat-Fallow System, Andrew W. Lenssen, Upendra M. Sainju, Hayes B. Goosey, Erin Snyder, Patrick G. Hatfield
Sheep Grazing Effect On Dryland Soil Carbon And Nitrogen In The Wheat-Fallow System, Andrew W. Lenssen, Upendra M. Sainju, Hayes B. Goosey, Erin Snyder, Patrick G. Hatfield
Andrew W. Lenssen
Weed control by sheep grazing during fallow periods in the dryland wheat-fallow system may influence soil C and N levels. The effects of fallow management for weed control and soil water conservation [sheep grazing (grazing), herbicide application (chemical), and tillage (mechanical)] and cropping sequence [continuous spring wheat (CSW), spring wheat-fallow (SW-F), and winter wheatfallow (WW-F)] on wheat biomass (stems + leaves) yield and soil organic C (SOC) and total N (STN) at the 0-120 cm depth was evaluated from 2004 to 2008 in western Montana. Annualized wheat biomass yield was greater in CSW than in SW-F and WW-F from 2004 …
Regional Assemblages Of Lygus (Heteroptera: Miridae) In Montana Canola Fields, Sue Blodgett, R. A. Ritter, A. W. Lenssen, M. L. Taper
Regional Assemblages Of Lygus (Heteroptera: Miridae) In Montana Canola Fields, Sue Blodgett, R. A. Ritter, A. W. Lenssen, M. L. Taper
Sue Blodgett
Sweep net sampling of canola (Brassica napus L.) was conducted in 2002 and 2003 to determine Lygus (Heteroptera: Miridae) species composition and parasitism levels in four regions of Montana. Regardless of region or seasonal change, Lygus elisus (Van Duzee) was the dominant species in all canola fields sampled, averaging 60–99% of the total adult populations. Lygus borealis (Kelton), Lygus keltoni (Schwartz) and Lygus lineolaris (Palisot) were detected at much lower levels. Total lygus population density was greatest in the southwest and central regions. The northeast and southwest regions had the greatest lygus species diversity. The proportion of L. elisus increased …
Synergism Between Entomopathogenic Nematodes And Bacillus Thuringiensis Crops: Integrating Biological Control And Resistance Management, Aaron J. Gassmann, S. Patricia Stock, Mark S. Sisterson, Yves Carriere, Bruce E. Tabashnik
Synergism Between Entomopathogenic Nematodes And Bacillus Thuringiensis Crops: Integrating Biological Control And Resistance Management, Aaron J. Gassmann, S. Patricia Stock, Mark S. Sisterson, Yves Carriere, Bruce E. Tabashnik
Aaron J. Gassmann
The past decade has witnessed a continual increase in the use of crops genetically modified to produce insecticidal toxins from the bacterium Bacillus thuringiensis (Bt). This presents the challenge of designing agricultural systems to manage pests and the evolution of resistance to Bt. We tested whether entomopathogenic nematodes might act synergistically with Bt crops by killing pests in non-Bt refuges and by increasing the fitness costs of resistance to Bt. We also tested whether insect mortality and fitness costs were affected by the cotton phytochemical gossypol. The entomopathogenic nematode Steinernema riobrave increased the fitness cost of Bt resistance, indicating that …
Evaluation Of Winter Cereals For Pasture In Montana, Andrew W. Lenssen, A. N. Hafla, S. D. Cash, L. M. M. Surber, J. A. Paterson, A. L. Todd, M. S. Huffman
Evaluation Of Winter Cereals For Pasture In Montana, Andrew W. Lenssen, A. N. Hafla, S. D. Cash, L. M. M. Surber, J. A. Paterson, A. L. Todd, M. S. Huffman
Andrew W. Lenssen
In the southern Great Plains, it is common to graze winter wheat pastures prior to grain harvest to take advantage of economic returns from the grain crop and value added to livestock. In Montana, a similar management practice could provide complementary pasture for livestock in the late spring to relieve pressure on cool season native rangelands. A two year study was conducted to evaluate the forage yield and quality of winter cereals, when grazed at three growth stages, vegetative (V), boot stage (B), and at heading (H), prior to hay and grain harvest. Western white faced ewes were used to …
Sheep Grazing Wheat Summer Fallow And The Impact On Soil Nitrogen, Moisture, And Crop Yield, Andrew W. Lenssen, E. E. Snyder, H. B. Goosey, P. G. Hatfield
Sheep Grazing Wheat Summer Fallow And The Impact On Soil Nitrogen, Moisture, And Crop Yield, Andrew W. Lenssen, E. E. Snyder, H. B. Goosey, P. G. Hatfield
Andrew W. Lenssen
In typical dryland farming areas of Montana, annual precipitation is not sufficient for annual harvest of small grains. Summer fallow in alternate years, is a common method of conserving soil moisture to produce a crop in the following season. Current methods of fallow management are primarily mechanical tillage and spraying with herbicides. Although these methods are effective, they are expensive, making fallow management the highest variable cost associated with dryland grain production. The objectives of this study were to compare the impact of grazing small grains stubble with sheep, as a fallow management tactic, against traditional management practices of chemical …
High-Level Resistance To Bacillus Thuringiensis Toxin Cry1ac And Cadherin Genotype In Pink Bollworm, Aaron J. Gassmann, Robert W. Biggs, Jeffrey A. Fabrick, Bruce E. Tabashnick, Timothy J. Dennehy, Yves Carriere, Shai Morin
High-Level Resistance To Bacillus Thuringiensis Toxin Cry1ac And Cadherin Genotype In Pink Bollworm, Aaron J. Gassmann, Robert W. Biggs, Jeffrey A. Fabrick, Bruce E. Tabashnick, Timothy J. Dennehy, Yves Carriere, Shai Morin
Aaron J. Gassmann
Resistance to transgenic cotton, Gossypium hirsutum L., producing Bacillus thuringiensis (Bt) toxin Cry1Ac is linked with three recessive alleles of a cadherin gene in laboratory-selected strains of pink bollworm, Pectinophora gossypiella (Saunders), a major cotton pest. Here, we analyzed a strain (MOV97-R) with a high frequency of cadherin resistance alleles, a high frequency of resistance to 10 μg of Cry1Ac per milliliter of diet, and an intermediate frequency of resistance to 1,000 μg of Cry1Ac per ml of diet. We selected two strains for increased resistance by exposing larvae from MOV97-R to diet with 1,000 μg of Cry1Ac per ml …
Incorporating Targeted Grazing Into Farming Systems, Andrew W. Lenssen, Patrick Hatfield, Hayes Goosey, Sue Blodgett
Incorporating Targeted Grazing Into Farming Systems, Andrew W. Lenssen, Patrick Hatfield, Hayes Goosey, Sue Blodgett
Andrew W. Lenssen
When incorporating targeted grazing into farming systems, livestock producers and farm operators need assurance that the benefits from their activities are worth their investments. This chapter will focus on how integrating grazing, particularly with sheep and goats, into farming systems can offer those benefits. The concepts are not new. Cropping systems were once integrated with livestock production: Livestock gained forage value from crop aftermath, crops were grown to sustain livestock, and livestock were used as implements to produce crops. Today, few cropping systems include livestock. Sheep and goats are traditionally produced on rangelands or pasture forages and supplemented during winter …
Pre-Euroamerican Distribution Of Pine Warblers (Dendroica Pinus) In Wisconsin: A Tool For Setting Regional Conservation Priorities, Lisa A. Schulte, Anna M. Pidgeon, David J. Mladenoff
Pre-Euroamerican Distribution Of Pine Warblers (Dendroica Pinus) In Wisconsin: A Tool For Setting Regional Conservation Priorities, Lisa A. Schulte, Anna M. Pidgeon, David J. Mladenoff
Lisa A. Schulte Moore
A common goal of conservation and management plans is to maintain populations of species of conservation concern at some historic level that was a product of environmental conditions at a time when they were less influenced by humans than at present. Conservation planning also includes consideration of the distribution, abundance, and reproductive success of a species, all of which are affected by both the amount and spatial pattern of habitat. In this work, we have fused the fields of spatial and historical ecology to provide a perspective that includes an estimate of a bird species’ distribution just prior to Euroamerican …
Induced Lsoflavonoids In Diverse Populations Of Astragalus Cicer, Andrew W. Lenssen, Susan S. Martin, Charley E. Townsend
Induced Lsoflavonoids In Diverse Populations Of Astragalus Cicer, Andrew W. Lenssen, Susan S. Martin, Charley E. Townsend
Andrew W. Lenssen
lsoflavonoids were induced in mature leaves of the legume Asbagalus cicer L. by spores of the fungus Bipoaris zeicola. The five major elicited compounds included two isoflavans (mucronulatol and astraciceran), two isoflavones (cajanin and acicerone), and a pterocarpan (maackiain). Only occasional traces of these compounds were detected in controls. Among 41 populations originating in Europe or Russia, mean total elicited isoflavonoid content differed 12-fold. Mucronulatol was the predominant compound elicited, comprising 20-70% of total isoflavonoids. Significant interpopulational differences existed for each isoflavonoid, but no geographic patterns of total or relative proportions of the five compounds were discernible.