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Full-Text Articles in Life Sciences
Seed Burial Physical Environment Explains Departures From Regional Hydrothermal Model Of Giant Ragweed (Ambrosia Trifida) Seedling Emergence In U.S. Midwest, Adam S. Davis, Sharon Clay, John Cardina, Frank Forcella, John Lundquist, Christy Sprague
Seed Burial Physical Environment Explains Departures From Regional Hydrothermal Model Of Giant Ragweed (Ambrosia Trifida) Seedling Emergence In U.S. Midwest, Adam S. Davis, Sharon Clay, John Cardina, Frank Forcella, John Lundquist, Christy Sprague
Agronomy, Horticulture and Plant Science Faculty Publications
Robust predictions of weed seedling emergence from the soil seedbank are needed to aid weed management. A common seed accession (Illinois) of giant ragweed was buried in replicate experimental gardens over 18 site years in Illinois, Michigan, Kansas, Nebraska, Ohio, and South Dakota to examine the importance of site and climate variability by year on seedling emergence. In a nonlinear mixed-effects modeling approach, we used a flexible sigmoidal function (Weibull) to model giant ragweed cumulative seedling emergence in relation to hydrothermal time accumulated in each site-year. An iterative search method across a range of base temperature (Tb ) and base …
Landscape Features Impact On Soil Available Water, Corn Biomass, And Gene Expression During The Late Vegetative Stage, Stephanie Hansen, Sharon A. Clay, David E. Clay, C. Gregg Carlson, Graig Reicks, Youssef Jarachi, David Horvath
Landscape Features Impact On Soil Available Water, Corn Biomass, And Gene Expression During The Late Vegetative Stage, Stephanie Hansen, Sharon A. Clay, David E. Clay, C. Gregg Carlson, Graig Reicks, Youssef Jarachi, David Horvath
Agronomy, Horticulture and Plant Science Faculty Publications
Crop yields at summit positions of rolling landscapes often are lower than backslope yields. The differences in plant response may be the result of many different factors. We examined corn (Zea mays L.) plant productivity, gene expression, soil water, and nutrient availability in two landscape positions located in historically high (backslope) and moderate (summit and shoulder) yielding zones to gain insight into plant response differences. Growth characteristics, gene expression, and soil parameters (water and N and P content) were determined at the V12 growth stage of corn. At tassel, plant biomass, N content, 13C isotope discrimination (Δ), and …
Insect Communities In Soybeans Of Eastern South Dakota: The Effects Of Vegetation Management And Pesticides On Soybean Aphids, Bean Leaf Beetles, And Their Natural Enemies, Jonathan G. Lundgren, Louis S. Hesler, Sharon A. Clay, Scott F. Fausti
Insect Communities In Soybeans Of Eastern South Dakota: The Effects Of Vegetation Management And Pesticides On Soybean Aphids, Bean Leaf Beetles, And Their Natural Enemies, Jonathan G. Lundgren, Louis S. Hesler, Sharon A. Clay, Scott F. Fausti
Agronomy, Horticulture and Plant Science Faculty Publications
Although most pests of soybeans, Gycine max (L.), in the Northern Great Plains are managed using pesticides, farm management practices that encourage biodiversity offer promising long-term, sustainable solutions for controlling insect and weed pests profitably. The recent invasion of the Northern Great Plains by the soybean aphid (Aphis glycinesMatsumura; Hemiptera: Aphididae) has had potentially important implications for insect communities in soybeans of this region, although recent descriptions of this regional community are scarce. We describe how three pest management systems that vary in the intensity with which they rely on herbicides and insecticides (chemically intensive, reduced chemical, and …
Spring Clipping, Fire, And Simulated Increased Atmospheric Nitrogen Deposition Effects On Tallgrass Prairie Vegetation, Alexander J. Smart, Tabitha K. Scott, Sharon A. Clay, David E. Clay, Michelle K. Ohrtman, Eric M. Mousel
Spring Clipping, Fire, And Simulated Increased Atmospheric Nitrogen Deposition Effects On Tallgrass Prairie Vegetation, Alexander J. Smart, Tabitha K. Scott, Sharon A. Clay, David E. Clay, Michelle K. Ohrtman, Eric M. Mousel
Agronomy, Horticulture and Plant Science Faculty Publications
Defoliation aimed at introduced cool-season grasses, which uses similar resources of native grasses, could substantially reduce their competitiveness and improve the quality of the northern tallgrass prairie. The objective was to evaluate the use of early season clipping and fire in conjunction with simulated increased levels of atmospheric nitrogen deposition on foliar canopy cover of tallgrass prairie vegetation. This study was conducted from 2009 to 2012 at two locations in eastern South Dakota. Small plots arranged in a split-plot treatment design were randomized in four complete blocks on a warm-season grass interseeded and a native prairie site in east-central South …