Publications by authors named "James T Brosnan"

As the Latin name annua implies, the species Poa annua L. is thought to have an annual life cycle. Yet, there are many reports in literature of P.

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Turfgrasses are perennial components of urban greenspaces found in parks, recreational areas, golf courses, sports fields, and lawns that confer many ecosystem services. A copious seed producer, Poa annua is the most troublesome weed of turfgrass and continually threatens the ecosystem services provided by urban greenspaces. Field research was conducted in Knoxville, TN to better understand environmental conditions triggering P.

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Background: Turfgrass managers reported poor Eleusine indica control following applications of the mitosis-inhibiting herbicide dithiopyr in cool-season turfgrass. Field, glasshouse, and laboratory experiments were conducted to understand the response of these biotypes to dithiopyr and prodiamine.

Results: In field experiments at two locations with putative dithiopyr-resistant E.

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Article Synopsis
  • Poa annua, a common weed, has developed resistance to multiple herbicides and this study focuses on a specific resistant biotype known as POAAN-R3.
  • Researchers explored how genes related to non-target site resistance (NTSR) behave in this biotype when exposed to the herbicide trifloxysulfuron, despite its known mutation at the target site.
  • The findings indicate that POAAN-R3 shows a unique gene expression response, particularly in genes related to transport and oxidative stress, suggesting these additional mechanisms may enhance the plant's ability to survive herbicide treatments.
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Experiments were conducted to understand environmental effects on efficacy of herbicides used to control goosegrass (Eleusine indica L. Gaertn.).

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Article Synopsis
  • Indaziflam is a herbicide used to control annual bluegrass, but reports of poor effectiveness surfaced in the southeastern USA, leading to tests for potential resistance in these grass populations.
  • Experimental results showed that while indaziflam worked effectively when applied before the grass emerged, it failed to control resistant bluegrass when applied after it had started growing, with notable differences in resistance levels compared to susceptible strains.
  • This is the first documented case of resistance to indaziflam, highlighting the grass's resistance to multiple other herbicides as well, with further research needed to understand the underlying mechanisms of this multi-herbicide resistance.
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Herbicides are pesticides used to eradicate unwanted plants in both crop and non-crop environments. These chemistries are toxic to weeds due to inhibition of key enzymes or disruption of essential biochemical processes required for weedy plants to survive. Crops can survive systemic herbicidal applications through various forms of detoxification, including metabolism that can be enhanced by safeners.

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Background: Interspecific hybrid bermudagrass [ (L.) Pers. x Burtt-Davy] is one of the most widely used grasses on golf courses, with cultivars derived from 'Tifgreen' or 'Tifdwarf' particularly used for putting greens.

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2,4-dimethylamine salt (2,4-D) is an herbicide commonly applied on athletic fields for broadleaf weed control that can dislodge from treated turfgrass. Dislodge potential is affected by numerous factors, including turfgrass canopy conditions. Building on previous research confirming herbicide-turfgrass dynamics can vary widely between species, field research was initiated in 2014 and 2015 in Raleigh, NC, USA to quantify dislodgeable 2,4-D residues from dormant hybrid bermudagrass (Cynodon dactylon L.

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Some interspecific hybrid bermudagrass cultivars used on golf course putting greens are genetically unstable, which has caused phenotypically different off-type grasses to occur in production nurseries and putting surfaces. Management practices to reduce the occurrence of off-type grasses in putting green surfaces and the effect they can have on putting quality and performance need to be researched until genetically stable cultivars are developed. Golf course putting green surfaces in subtropical and tropical climates are typically planted with an interspecific hybrid bermudagrass (Cynodon dactylon (L.

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Research to date has confirmed 2,4-D residues may dislodge from turfgrass; however, experiments have not been conducted on hybrid bermudagrass (Cynodon dactylon L. x C. transvaalensis), the most common athletic field turfgrass in subtropical climates.

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Article Synopsis
  • A mutation known as Ala-205-Phe in acetolactate synthase has been identified that provides resistance to multiple herbicides, including imidazolinone and sulfonylurea.
  • A specific population of annual bluegrass (Poa annua L.; POAAN-R3) from Tennessee exhibited this resistance alongside a mutation in the psbA gene that leads to a Ser-264-Gly change in the D1 protein.
  • This study marks the first documentation of the Ala-205-Phe substitution granting extensive resistance to herbicides that inhibit acetolactate synthase, demonstrating its implications for herbicide management in turfgrass.
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Creeping bentgrass (Agrostis stolonifera L.) is moderately tolerant to the p-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide topramezone. However, the contribution of plant metabolism of topramezone to this tolerance is unknown.

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Higher ACL injury rates have been recorded in cleats with higher torsional resistance in American football, which warrants better understanding of shoe/stud-dependent joint kinetics. The purpose of this study was to determine differences in knee and ankle kinetics during single-leg land cuts and 180° cuts on synthetic infilled turf while wearing 3 types of shoes. Fourteen recreational football players performed single-leg land cuts and 180° cuts in nonstudded running shoes (RS) and in football shoes with natural (NTS) and synthetic turf studs (STS).

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Multiple playing surfaces and footwear used in American football warrant a better understanding of relationship between different combinations of turf and footwear. The purpose of this study was to examine effects of shoe and stud types on ground reaction force (GRF) and ankle and knee kinematics of a 180° cut and a single-leg 90° land-cut on synthetic turf. Fourteen recreational football players performed five trials of the 180° cut and 90° land-cut in three shoe conditions: non-studded running shoe, and football shoe with natural and synthetic turf studs.

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One attractive strategy to discover more active and/or crop-selective herbicides is to make structural changes to currently registered compounds. This strategy is especially appealing for those compounds with limited herbicide resistance and whose chemistry is accompanied with transgenic tools to enable herbicide tolerance in crop plants. Bromoxynil is a photosystem II (PSII) inhibitor registered for control of broadleaf weeds in several agronomic and specialty crops.

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