Browsing by Author "Wright, David L."

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    Foliar fertilizers rarely increase yield in United States soybean
    Matcham, Emma G.; Vann, R. Atwell; Lindsey, Laura E.; Gaska, John M.; Lilley, Dylan T.; Ross, W. Jeremy; Wright, David L.; Knott, Carrie; Lee, Chad D.; Moseley, David; Singh, Maninder; Naeve, Seth L.; Irby, J. Trenton; Wiebold, William J.; Kandel, Hans; Lofton, Josh; Inman, Matthew; Kleinjan, Jonathon; Holshouser, David L.; Conley, Shawn P. (2021-09-25)
    Farmers have been interested in using foliar-applied nutrient products to increase soybean [Glycine max (L.) Merr.] yield since at least the 1970s, despite limited evidence that these products offer consistent yield increases when used prophylactically. Recently, interest in foliar fertilizer products for soybean production has been renewed, likely related to elevated soybean prices. Over the 2019 and 2020 growing seasons (46 site-years), agronomists in 16 states collaborated to test six foliar nutrient treatments (commercial mixtures of macro- and micro-nutrients) on soybean grain yield and composition. Soybean grain yield and composition differed among sites but not among foliar fertilizer treatments. Results show that prophylactic foliar fertilization is likely to decrease the profitability of soybean production. Foliar fertilizer products tested in this study and similar products should not be recommended to U.S. soybean farmers in the absence of visual symptoms of nutrient deficiency.
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    Linking soil microbial community structure to potential carbon mineralization: A continental scale assessment of reduced tillage
    Rieke, Elizabeth L.; Cappellazzi, Shannon B.; Cope, Michael; Liptzin, Daniel; Mac Bean, G.; Greub, Kelsey L. H.; Norris, Charlotte E.; Tracy, Paul W.; Aberle, Ezra; Ashworth, Amanda; Banuelos Tavarez, Oscar; Bary, Andy, I; Baumhardt, R. L.; Borbon Gracia, Alberto; Brainard, Daniel C.; Brennan, Jameson R.; Briones Reyes, Dolores; Bruhjell, Darren; Carlyle, Cameron N.; Crawford, James J. W.; Creech, Cody F.; Culman, Steve W.; Deen, Bill; Dell, Curtis J.; Derner, Justin D.; Ducey, Thomas F.; Duiker, Sjoerd W.; Dyck, Miles F.; Ellert, Benjamin H.; Espinosa Solorio, Avelino; Fonte, Steven J.; Fonteyne, Simon; Fortuna, Ann-Marie; Foster, Jamie L.; Fultz, Lisa M.; Gamble, Audrey, V; Geddes, Charles M.; Griffin-LaHue, Deirdre; Grove, John H.; Hamilton, Stephen K.; Hao, Xiying; Hayden, Zachary D.; Honsdorf, Nora; Howe, Julie A.; Ippolito, James A.; Johnson, Gregg A.; Kautz, Mark A.; Kitchen, Newell R.; Kumar, Sandeep; Kurtz, Kirsten S. M.; Larney, Francis J.; Lewis, Katie L.; Liebman, Matt; Lopez Ramirez, Antonio; Machado, Stephen; Maharjan, Bijesh; Martinez Gamino, Miguel Angel; May, William E.; McClaran, Mitchel P.; McDaniel, Marshall D.; Millar, Neville; Mitchell, Jeffrey P.; Moore, Amber D.; Moore, Philip A.; Mora Gutierrez, Manuel; Nelson, Kelly A.; Omondi, Emmanuel C.; Osborne, Shannon L.; Osorio Alcala, Leodegario; Owens, Philip; Pena-Yewtukhiw, Eugenia M.; Poffenbarger, Hanna J.; Ponce Lira, Brenda; Reeve, Jennifer R.; Reinbott, Timothy M.; Reiter, Mark S.; Ritchey, Edwin L.; Roozeboom, Kraig L.; Rui, Yichao; Sadeghpour, Amir; Sainju, Upendra M.; Sanford, Gregg R.; Schillinger, William F.; Schindelbeck, Robert R.; Schipanski, Meagan E.; Schlegel, Alan J.; Scow, Kate M.; Sherrod, Lucretia A.; Shober, Amy L.; Sidhu, Sudeep S.; Solis Moya, Ernesto; St Luce, Mervin; Strock, Jeffrey S.; Suyker, Andrew E.; Sykes, Virginia R.; Tao, Haiying; Trujillo Campos, Alberto; Van Eerd, Laura L.; Verhulst, Nele; Vyn, Tony J.; Wang, Yutao; Watts, Dexter B.; William, Bryan B.; Wright, David L.; Zhang, Tiequan; Morgan, Cristine L. S.; Honeycutt, C. Wayne (Pergamon-Elsevier, 2022-05)
    Potential carbon mineralization (Cmin) is a commonly used indicator of soil health, with greater Cmin values interpreted as healthier soil. While Cmin values are typically greater in agricultural soils managed with minimal physical disturbance, the mechanisms driving the increases remain poorly understood. This study assessed bacterial and archaeal community structure and potential microbial drivers of Cmin in soils maintained under various degrees of physical disturbance. Potential carbon mineralization, 16S rRNA sequences, and soil characterization data were collected as part of the North American Project to Evaluate Soil Health Measurements (NAPESHM). Results showed that type of cropping system, intensity of physical disturbance, and soil pH influenced microbial sensitivity to physical disturbance. Furthermore, 28% of amplicon sequence variants (ASVs), which were important in modeling Cmin, were enriched under soils managed with minimal physical disturbance. Sequences identified as enriched under minimal disturbance and important for modeling Cmin, were linked to organisms which could produce extracellular polymeric substances and contained metabolic strategies suited for tolerating environmental stressors. Understanding how physical disturbance shapes microbial communities across climates and inherent soil properties and drives changes in Cmin provides the context necessary to evaluate management impacts on standardized measures of soil microbial activity.
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    Structuring State Policy for Student Success - Applying Incentives in the Volunteer State
    Wright, David L. (Lumina Foundation, 2016-03-01)
    This report focuses on Tennessee’s experience in responding to the college completion imperative by implementing an array of policies and programs representing incentives to either institutions or students. The Tennessee experience is pertinent to other states because: with only 36 percent of its adult residents holding a postsecondary certificate or higher (ranked 42nd nationally), Tennessee has a long way to go in terms of educational attainment; it has made substantial strides in a short time; and it shares enough characteristics with enough states to make its experience relevant across a variety of state contexts.