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Full-Text Articles in Life Sciences
Tolerance And Velvetleaf (Abutilon Theophrasti) Suppressive Ability Of Two Old And Two Modern Corn (Zea Mays) Hybrids, John L. Lindquist, David A. Mortensen
Tolerance And Velvetleaf (Abutilon Theophrasti) Suppressive Ability Of Two Old And Two Modern Corn (Zea Mays) Hybrids, John L. Lindquist, David A. Mortensen
Department of Agronomy and Horticulture: Faculty Publications
Improved crop tolerance and weed suppressive ability are tactics that may reduce the negative effect of weeds on crop yield. Irrigated field experiments were conducted to compare leaf area index (LAI), intercepted photosynthetic photon flux (PPF), and relative tolerance and velvetleaf suppressive ability among two old (circa1 940) and two modern corn hybrids. Each hybrid was grown in monoculture and in mixture with velvetleaf at 1, 4, 16, and 40 plants m-1 row. Plants were periodically harvested in monoculture plots to obtain estimates of corn LAI, and PPF interception was measured. Variation in hybrid tolerance to velvetleaf competition for …
Economic Importance Of Managing Spatially Heterogeneous Weed Population, John L. Lindquist, J. Anita Dieleman, David A. Mortensen, Gregg A. Johnson, Dawn Y. Wyse-Pester
Economic Importance Of Managing Spatially Heterogeneous Weed Population, John L. Lindquist, J. Anita Dieleman, David A. Mortensen, Gregg A. Johnson, Dawn Y. Wyse-Pester
Department of Agronomy and Horticulture: Faculty Publications
Three methods of predicting the impact of weed interference on crop yield and expected economic return were compared to evaluate the economic importance of weed spatial heterogeneity. Density of three weed species was obtained using a grid sampling scheme in 11 corn and 11 soybean fields. Crop yield loss was predicted assuming densities were homogeneous, aggregated following a negative binomial with known population mean and k, or aggregated with weed densities spatially mapped. Predicted crop loss was lowest and expected returns highest when spatial location of weed density was utilized to decide whether control was justified. Location-specific weed management resulted …