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Full-Text Articles in Agronomy and Crop Sciences
Comparative Ecophysiology Of Grain Sorghum And Abutilon Theophrasti In Monoculture And In Mixture, Samba Traoré, John L. Lindquist, Stephen Mason, Alex Martin, D. A. Mortensen
Comparative Ecophysiology Of Grain Sorghum And Abutilon Theophrasti In Monoculture And In Mixture, Samba Traoré, John L. Lindquist, Stephen Mason, Alex Martin, D. A. Mortensen
John L. Lindquist
Selection of crop genotypes that are more competitive with weeds for light interception may improve crop yield stability in the presence of weeds. The effects of interference on ecophysiological characteristics of Abutilon theophrasti Medic. and three morphologically diverse grain sorghum hybrids was evaluated to determine the relative tolerance and suppressive ability of the three hybrids and specific traits that may contribute to those differences. A tall hybrid was more tolerant to A. theophrasti interference than two medium stature hybrids. Early leaf area growth of two medium-stature sorghum hybrids was reduced by A. theophrasti interference, whereas early growth of a tall …
Influence Of Nitrogen And Duration Of Weed Interference On Corn Growth And Development, Sean P. Evans, Stevan Z. Knezevic, John L. Lindquist, Charles A. Shapiro
Influence Of Nitrogen And Duration Of Weed Interference On Corn Growth And Development, Sean P. Evans, Stevan Z. Knezevic, John L. Lindquist, Charles A. Shapiro
John L. Lindquist
An improved understanding of the effects of nitrogen (N) on crop–weed interactions is needed for the development of integrated weed management systems where responsible use of N fertilizers is considered. Field experiments conducted in 1999 and 2000 at two locations in eastern Nebraska quantify the effects of N and increasing duration of weed interference on corn growth and development. A naturally occurring population of weeds was allowed to compete with the corn crop for increasing lengths of time and at three rates of N application (0, 60, and 120 kg N ha-1). Weed interference and withholding applied N increased the …
Simulated Insect Defoliation And Duration Of Weed Interference Affected Soybean Growth, Travis C. Gustafson, Stevan Z. Knezevic, Thomas E. Hunt, John L. Lindquist
Simulated Insect Defoliation And Duration Of Weed Interference Affected Soybean Growth, Travis C. Gustafson, Stevan Z. Knezevic, Thomas E. Hunt, John L. Lindquist
John L. Lindquist
An improved understanding of crop stress from multiple pests is needed for better implementation of integrated pest management (IPM) strategies. Field studies were conducted in 2003 and 2004 at two locations in eastern Nebraska to describe the effects of simulated early-season insect defoliation of soybean and duration of weed interference on soybean growth. Three levels of simulated defoliation (undefoliated, 30, and 60%) and seven durations of weed interference (weedy and weed free; weed removal at V2, V4, V6, R3, and R5) were evaluated in a split-plot design. Defoliation significantly reduced soybean leaf-area index (LAI), total dry matter (TDM), and crop …
Comparative Nitrogen Uptake And Distribution In Corn And Velvetleaf (Abutilon Theophrasti), John L. Lindquist, Darren C. Barker, Stevan Z. Knezevic, Alexander R. Martin, Daniel T. Walters
Comparative Nitrogen Uptake And Distribution In Corn And Velvetleaf (Abutilon Theophrasti), John L. Lindquist, Darren C. Barker, Stevan Z. Knezevic, Alexander R. Martin, Daniel T. Walters
John L. Lindquist
Weeds compete with crops for light, soil water, and nutrients. Nitrogen (N) is the primary limiting soil nutrient. Forecasting the effects of N on growth, development, and interplant competition requires accurate prediction of N uptake and distribution within plants. Field studies were conducted in 1999 and 2000 to determine the effects of variable N addition on monoculture corn and velvetleaf N uptake, the relationship between plant N concentration ([N]) and total biomass, the fraction of N partitioned to leaves, and predicted N uptake and leaf N content. Cumulative N uptake of both species was generally greater in 2000 than in …