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Full-Text Articles in Agronomy and Crop Sciences
Herbicide And Additive Impacts On Bradyrhizobium Japonicum Growth In Solution, Joy Amajioyi, Thandiwe Nleya, Senthil Subramanian, Sharon A. Clay
Herbicide And Additive Impacts On Bradyrhizobium Japonicum Growth In Solution, Joy Amajioyi, Thandiwe Nleya, Senthil Subramanian, Sharon A. Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Plant biostimulants include beneficial fungi and bacteria, and are often applied to foliage to improve crop growth, yield, and/or crop quality. Crop improvements due to biostimulant addition may be modest; therefore, solo applications may not be economical or climate smart. However, biostimulants combined with other postemergence treatments, such as herbicides, may provide an alternative application method, if mixtures do not harm the living organism(s). The growth of Bradyrhizobium japonicum, as a biostimulant surrogate, was assessed in solutions of glyphosate [N-(phosphonomethyl)glycine] and dicamba (3,6-dichloro-2-methoxybenzoic acid), with and without common spray additives (ammonium sulfate [AMS] and nonionic surfactant) in laboratory studies over …
Weed-Induced Crop Yield Loss: A New Paradigm And New Challenges, David Horvath, Sharon A. Clay, Clarence J. Swanton, James V. Anderson, Wun S. Chao
Weed-Induced Crop Yield Loss: A New Paradigm And New Challenges, David Horvath, Sharon A. Clay, Clarence J. Swanton, James V. Anderson, Wun S. Chao
Agronomy, Horticulture and Plant Science Faculty Publications
Direct competition for resources is generally considered the primary mechanism for weed-induced yield loss. A re-evaluation of physiological evidence suggests weeds initially impact crop growth and development through resource-independent interference. We suggest weed perception by crops induce a shift in crop development, before resources become limited, which ultimately reduce crop yield, even if weeds are subsequently removed. We present the mechanisms by which crops perceive and respond to weeds and discuss the technologies used to identify these mechanisms. These data lead to a fundamental paradigm shift in our understanding of how weeds reduce crop yield and suggest new research directions …
Auxin-Based Herbicide Program For Weed Control In Auxin Resistant Soybean, Joy Amajioyi, Thandiwe Nleya, Graig Reicks, Janet Moriles- Miller, David Clay, Sharon Clay
Auxin-Based Herbicide Program For Weed Control In Auxin Resistant Soybean, Joy Amajioyi, Thandiwe Nleya, Graig Reicks, Janet Moriles- Miller, David Clay, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Soybean [Glycine max (L.) Merr.] cultivars resistant to synthetic auxin herbicides have provided another mode of action for the postemergence broadleaf weed control. This field study was conducted at three South Dakota locations [Northeast, NERF; east-central, ARF; and Southeast, SERF) in 2019 and two locations (ARF and SERF) in 2020. The Enlist E3 and Roundup Ready 2 Xtend cultivars were planted at three dates (early, mid-, and late season) to examine weed control, agronomic characteristics, nodulation, and yield. Preemergence (PRE) treatment was flumioxazin + metribuzin + S-metolachlor + glyphosate + pendimethalin. Two postemergence (POST) treatments, based on cultivar, were compared …
Near Term Challenges For Global Agriculture - Herbicide Resistant Weeds, Sharon Clay
Near Term Challenges For Global Agriculture - Herbicide Resistant Weeds, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Prior to the 1950s weeds were controlled by a wide variety of mechanical and cultural methods with limited use of inorganic chemicals at very high rates (100s kg ha–1). With the advent of selective carbon-based herbicides in the 1950s, herbicide weed management became the norm throughout much of the world using grams to a few kg of active ingredient per ha. However, with the benefits, there are problems. A few resistant weeds were recognized in the 1970s, but today, in 2021, 521 unique cases of resistance have been documented throughout the world. It is imperative for farmers to rethink the …
Weed Presence Altered Biotic Stress And Light Signaling In Maize Even When Weeds Were Removed Early In The Critical Weed‐Free Period, David P. Horvath, Stephanie Bruggeman, Janet Moriles-Miller, James V. Anderson, Munevver Dogramaci, Brian E. Scheffler, Alvaro G. Hernandez, Michael E. Foley, Sharon Clay
Weed Presence Altered Biotic Stress And Light Signaling In Maize Even When Weeds Were Removed Early In The Critical Weed‐Free Period, David P. Horvath, Stephanie Bruggeman, Janet Moriles-Miller, James V. Anderson, Munevver Dogramaci, Brian E. Scheffler, Alvaro G. Hernandez, Michael E. Foley, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Weed presence early in the life cycle of maize (typically, from emergence through the 8 to 12 leaf growth stage) can reduce crop growth and yield and is known as the critical weed‐free period (CWFP). Even if weeds are removed during or just after the CWFP, crop growth and yield often are not recoverable. We compared transcriptome responses of field‐grown hybrid maize at V8 in two consecutive years among plants grown under weed‐free and two weed‐stressed conditions (weeds removed at V4 or present through V8) using RNAseq analysis techniques. Compared with weed‐free plant responses, physiological differences at V8 were identified …
Propelled Abrasive Grit For Weed Control In Organic Silage Corn, Mauricio Erazo-Barradas, Fran Forcella, Dan Humburg
Propelled Abrasive Grit For Weed Control In Organic Silage Corn, Mauricio Erazo-Barradas, Fran Forcella, Dan Humburg
Agronomy, Horticulture and Plant Science Faculty Publications
Weed management in organic farming requires many strategies to accomplish acceptable control and maintain crop yields. This 2-yr field study used air propelled abrasive grit for in-row weed control in organically certified silage corn (Zea mays L.). Corncob grit was applied as a single application at corn vegetative growth stages V1 (one true leaf; numbers correspond to number of true leaves at the corn vegetative stage), V3, or V5 (in 2013) and V3, V5, and V7 (in 2014) and in double and triple combinations at these stages. Between-row weed control was accomplished by flaming or cultivation after the last grit …
Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus
Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus
Agronomy, Horticulture and Plant Science Faculty Publications
Common waterhemp (Amarathus rudis Sauer) is a frequent weed in glyphosate-resistant (GR) crops in the midwestern USA due, in part, to the delayed emergence of its seedlings. Variable waterhemp emergence was simulated by transplanting seedlings into both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] and bare plot areas at differing crop growth stages during two growing seasons in western Minnesota. Growth and fecundity were measured. As expected, late planted weeds produced little dry matter and few seeds, and competition from corn or soybean reduced waterhemp dry weight and fecundity by 90% compared with isolated plants. Interestingly, common …
Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury
Analysis Of Spatial Distribution Of Canada Thistle (Cirsium Arvense) In Notill Soybean (Glycine Max), B. L. Broulik, J. Lems, S. A. Clay, D. E. Clay, M. M. Ellsbury
Agronomy, Horticulture and Plant Science Faculty Publications
The nonuniform spatial distribution of weeds across a field landscape complicates sampling and modeling, but allows site specific rather than broadcast management of weed populations. Where weeds are aggregated, densities measured at random locations are not independent, but rather spatially related or autocorrelated. Geostatistical methods were used to describe and map nonrandom distribution and variation of shoot density across ten well established patches of Canada thistle, a perennial weed, in a 65 hectare notillage soybean field in Moody county, South Dakota in 1996. Canada thistle densities were determined by counting the number of shoots present in a 20 by 50 …
Atrazine And Alachlor Adsorption Characteristics To Benchmark Soil Series In Eastern South Dakota, Z. Liu, S. A. Clay, J. Gaffney, D. Malo
Atrazine And Alachlor Adsorption Characteristics To Benchmark Soil Series In Eastern South Dakota, Z. Liu, S. A. Clay, J. Gaffney, D. Malo
Agronomy, Horticulture and Plant Science Faculty Publications
Corn, grain sorghum, and soybean are grown on about six million acres in eastern South Dakota each year. Two herbicides used routinely for weed control are atrazine(6-chloro-N-ethyl-N’-(1-methylethyl)-1,3,5-triazine-2,4-diamine) in corn and grain sorghum and alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) in all three crops. Six benchmark soil series that include a majority of the cropped acres treated with these herbicides are the Egan, Moody, Nora, and Brandt silty clay loams, and Clarno and Enet loams. Batch adsorption studies determined atrazine and alachlor binding characteristics to these soils and aids in assessing the amount of herbicide available for movement. These data also provide a basis for …