Browsing by Author "McMaster, Nicole J."

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    Modification of the Mycotoxin Deoxynivalenol Using Microorganisms Isolated from Environmental Samples
    Wilson, Nina M.; McMaster, Nicole J.; Gantulga, Dash; Soyars, Cara L.; McCormick, Susan P.; Knott, Ken; Senger, Ryan S.; Schmale, David G. III (MDPI, 2017-04-01)
    The trichothecene mycotoxin deoxynivalenol (DON) is a common contaminant of wheat, barley, and maize. New strategies are needed to reduce or eliminate DON in feed and food products. Microorganisms from plant and soil samples collected in Blacksburg, VA, USA, were screened by incubation in a mineral salt media containing 100 μg/mL DON and analysis by gas chromatography mass spectrometry (GC/MS). Two mixed cultures derived from soil samples consistently decreased DON levels in assays using DON as the sole carbon source. Nuclear magnetic resonance (NMR) analysis indicated that 3-keto-4-deoxynivalenol was the major by-product of DON. Via 16S rRNA sequencing, these mixed cultures, including mostly members of the genera Acinetobacter, Leadbetterella, and Gemmata, were revealed. Incubation of one of these mixed cultures with wheat samples naturally contaminated with 7.1 μg/mL DON indicated nearly complete conversion of DON to the less toxic 3-epimer-DON (3-epi-DON). Our work extends previous studies that have demonstrated the potential for bioprospecting for microorganisms from the environment to remediate or modify mycotoxins for commercial applications, such as the reduction of mycotoxins in fuel ethanol co-products.
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    A mycotoxin transporter (4D) from a library of deoxynivalenol-tolerant microorganisms
    Jimenez-Sanchez, Celia; Wilson, Nina M.; McMaster, Nicole J.; Gantulga, Dash; Freedman, Benjamin G.; Senger, Ryan S.; Schmale, David G. III (Elsevier, 2020-03-01)
    New strategies are needed to mitigate the mycotoxin deoxynivalenol (DON) in feed and food products. Microbial DNA fragments were generated from a library of DON-tolerant microorganisms. These fragments were screened in DON-sensitive yeast strains for their ability to modify or transport DON. Fragments were cloned into a PCR8/TOPO vector, and recombined into the yeast vector, pYES-DEST52. Resulting yeast transformants were screened in the presence of 100 ppm DON. Transformants that were able to grow in the presence of DON were plated on a selective medium, and the cloned microbial DNA fragments were sequenced. BLAST queries of one microbial DNA fragment (4D) showed a high degree of similarity to an ABC transporter. A series of screening and inhibition assays were conducted with a transport inhibitor (propanol), to test the hypothesis that 4D is a mycotoxin transporter. DON concentrations did not change for yeast transformants expressing 4D. The ability of yeast transformants expressing 4D to transport DON was inhibited by the addition of propanol. Moreover, yeast transformants expressing a known efflux pump (PDR5) showed similar trends in propanol transport inhibition compared to 4D. Future work should consider mycotoxin transporters such as 4D to the development of transgenic plants to limit DON accumulation in seeds.
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    Registration of 'Hilliard' wheat
    Griffey, Carl A.; Malla, Subas; Brooks, Wynse S.; Seago, John E.; Christopher, Anthony; Thomason, Wade E.; Pitman, Robert M.; Markham, Robin; Vaughn, Mark E.; Dunaway, David W.; Beahm, Mary; Barrack, C. Lin; Rucker, Elizabeth; Behl, Harry D.; Hardiman, Thomas H.; Beahm, Bruce R.; Browning, Phillip; Schmale, David G. III; McMaster, Nicole J.; Custis, J. Tommy; Gulick, Steve; Ashburn, S. Bobby; Jones, Ned, Jr.; Baik, Byung-Kee; Bockelman, Harold; Marshall, David; Fountain, Myron O.; Brown-Guedira, Gina L.; Cowger, Christina; Cambron, Sue; Kolmer, James; Jin, Yue; Chen, Xianming; Garland-Campbell, Kimberly; Sparry, Ellen (2020-09)
    'Hilliard' (Reg. no. CV-1163, PI 676271), a soft red winter (SRW) wheat (Triticum aestivum L.) developed and tested as VA11W-108 by the Virginia Agricultural Experiment Station, was released in March 2015. Hilliard was derived from the cross '25R47'/'Jamestown'. Hilliard is widely adapted, from Texas to Ontario, Canada, and provides producers with a mid-season, medium height, awned, semi-dwarf (Rht2) cul tivar that has very high yield potential, good straw strength, and intermediate grain volume weight and quality. It expresses moderate to high levels of resistance to most diseases prevalent in the eastern United States and Ontario. In the 2016-2018 USDA-ARS Uniform SRW Wheat nurseries, Hilliard ranked first in grain yield in the southern nursery across all 3 yr (5,147-5,758 kg ha(-1)). In the uniform eastern nursery, it ranked first for grain yield in 2016 (6,159 kg ha(-1)) and 2017 (5,633 kg ha(-1)) and second in 2018 (5,515 kg ha(-1)). Grain volume weights of Hilliard were similar to overall trial averages in the uniform southern (73.4-75.2 kg hl(-1)) and eastern (70-75.8 kg hl(-1)) nurseries. Hilliard has soft grain texture with flour softness equivalent values varying from 58.1 to 61.7 g 100 g(-1). Straight grade flour yields on a Quadrumat Senior mill varied from 66.8 to 68.4 g kg(-1). Flour protein concentration varied from 7.0 to 9.1 g 100 g(-1) and gluten strength from 108 to 128 g 100 g(-1), as measured by lactic acid solvent retention capacity. Cookie spread diameter varied from 18.3 to 18.6 cm.
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    Registration of 'SB255' winter barley
    Brooks, Wynse S.; Griffey, Carl A.; Vaughn, Mark E.; Seago, John E.; Thomason, Wade E.; Fitzgerald, Joshua; Christopher, Anthony; Pitman, Robert M.; Dunaway, David W.; Light, Jon; Rucker, Elizabeth; Behl, Harry D.; Beahm, Bruce R.; Browning, Phillip; McMaster, Nicole J.; Schmale, David G. III; Hardiman, Thomas H.; Custis, J. Tommy; Gulick, Steve; Ashburn, S. Bobby; Jones, Ned, Jr.; Marshall, David; Fountain, Myron O.; Tan Tuong; Oakes, Joseph C. (2021-05)
    'SB255' (Reg. no. CV-373, PI 693987) is a six-rowed hulled barley (Hordeum vulgare L.) cultivar with winter growth habit. The cultivar was released by the Virginia Agricultural Experiment Station in May 2019. SB255 is widely adapted, high yielding, high grain volume weight, and medium tall. It has good winterhardiness and good straw strength. The spikes of SB255 are strap and slightly waxy with no overlapping lateral kernels and with long awns. Prior to being named, SB255 was tested under the experimental designation VA11B-141 (LA). It was derived from the cross Spont03-44/VA01B-44 and developed using a modified-bulk breeding method. It was evaluated from 2013 to 2019 in the Virginia Official Variety Trials at five to six locations. SB255's average grain yield (5,214 kg ha(-1)) was similar to the check cultivars 'Secretariat' and 'Thoroughbred' but significantly (P <= .05) higher than 'Atlantic', 'Price', 'Callao', 'Nomini', and 'Wysor'. Average grain volume weight of SB255 (60.8 kg hL(-1)) was similar to Secretariat and Price but exceeded (P <= 0.05) those of Thoroughbred, Atlantic, Callao, Nomini, and Wysor. Head emergence of SB255 was similar to Thoroughbred and 2-5 d later than winter feed barley cultivars Secretariat, Atlantic, Price, Callao, and Nomini. SB255 was developed primarily as a feed barley cultivar. It provides barley producers and end users in the eastern United States with a high-grain-yielding cultivar having good to moderate resistance to all diseases prevalent in the eastern United States, including Fusarium head blight (FHB), and also lower deoxynivalenol (DON) accumulation in the grain.
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    Registration of 'Secretariat' Winter Barley
    Griffey, Carl A.; Brooks, Wynse S.; Vaughn, Mark E.; Berger, Gregory L.; Thomason, Wade E.; Pitman, Robert M.; Malla, Subas; Seago, John E.; Dunaway, David W.; Rucker, Elizabeth; Behl, Harry D.; Browning, Phillip; Schmale, David G. III; McMaster, Nicole J.; Hardiman, Thomas H.; Custis, J. Tommy; Starner, David Eugene; Gulick, Steve; Ashburn, S. Bobby; Jones, E. H.; Marshall, David; Fountain, Myron O.; Tuong, Tan Duy; Kurantz, Michael J.; Moreau, Robert A.; Hicks, Kevin B. (2016-08-30)
    ‘Secretariat’ (Reg. No. CV-359, PI 673931) is a six-row hulled winter barley (Hordeum vulgare L.) developed by the Virginia Agricultural Experiment Station and released in May 2014. Secretariat, formerly designated VA08B-85, was derived from the cross VA00B-199/VA00B-259 and developed using a modified bulk breeding method. It was evaluated from 2012 to 2015 in the Virginia Official Variety Trials at five to six locations. Secretariat’s average grain yield (5907 kg ha−1) was higher than the check cultivars ‘Atlantic’, ‘Price’, ‘Callao’, ‘Nomini’, and ‘Wysor’ and similar to ‘Thoroughbred’. Average grain volume weight of Secretariat (61.1 kg hL−1) was similar to Thoroughbred, Atlantic, Price, and Callao and higher than Nomini and Wysor. Head emergence of Secretariat is 6 d earlier than the predominant cultivar Thoroughbred. Earlier maturity is a primary factor determining whether barley or wheat (Triticum aestivum L.) is used in double-cropping systems with soybean [Glycine max (Merr.) L.]. Grain of Secretariat produced an average starch concentration (56.9%) that was higher than Price and Callao, similar to Atlantic, but lower than Thoroughbred. Secretariat provides barley producers and end users in the eastern United States with a high-yielding, widely adapted, early-maturing winter barley cultivar that has good grain quality and is highly resistant to leaf rust (caused by Puccinia hordei G. Otth) and powdery mildew [caused by Blumeria graminis (DC.) E.O. Speer f. sp. hordei Em. Marchal].
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    Survey of Mycotoxins in Corn Distillers’ Dried Grains with Solubles from Seventy-Eight Ethanol Plants in Twelve States in the U.S. in 2011
    Khatibi, Piyum A.; McMaster, Nicole J.; Musser, Robert; Schmale, David G. III (MDPI, 2014-03-26)
    Fuel ethanol co-products known as distillers’ dried grains with solubles (DDGS) are a significant source of energy, protein, and phosphorous in animal feed. Fuel ethanol production may concentrate mycotoxins present in corn into DDGS. One hundred and forty one corn DDGS lots collected in 2011 from 78 ethanol plants located in 12 states were screened for the mycotoxins deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON), 3-acetyldeoxynivalenol (3-ADON), nivalenol (NIV), and zearalenone (ZON). DON ranged from <0.50 to 14.62 μg g−1, 15-ADON ranged from <0.10 to 7.55 μg g−1, and ZON ranged from <0.10 to 2.12 μg g−1. None of the DDGS lots contained 3-ADON or NIV. Plants in OH had the highest levels of DON overall (mean of 9.51 μg g−1), and plants in NY, MI, IN, NE, and WI had mean DON levels >1 and <4 μg g−1. Twenty six percent (36/141) of the DDGS lots contained 1.0 to 5.0 μg g−1 DON, 2% (3/141) contained >5.0 and <10.0 μg g−1 DON, and 3% (4/141) contained >10.0 μg g−1 DON. All DDGS lots contaminated with unacceptable levels of DON evaded detection prior to their commercial distribution and were likely sold as feed products.
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    Tri5 gene expression analysis during postharvest storage of wheat grain from field plots treated with a triazole and a strobilurin fungicide
    Bolanos-Carriel, Carlos; Wegulo, Stephen N.; Baenziger, P. Stephen; Eskridge, Kent M.; Funnell-Harris, Deanna; McMaster, Nicole J.; Schmale, David G. III; Hallen-Adams, Heather E. (2020-10-01)
    Fusarium head blight (FHB) and the associated mycotoxin deoxynivalenol (DON) negatively impact the wheat industry worldwide. In North America, FHB is mainly caused by Fusarium graminearum sensu stricto. The purpose of this study was to evaluate, under storage conditions, the expression of the DON biosynthetic gene trichodiene synthase (Tri5) of F. graminearum in grain of hard red winter wheat cultivars 'Overley' (FHB-susceptible) and 'Overland' (moderately resistant to FHB) from field plots treated or untreated with the triazole fungicide Prosaro and the strobilurin fungicide Headline. Infected grain was stored and periodically sampled to determine gene expression by qRT-PCR analysis. The F. graminearum housekeeping gene GAPDH was consistently detected, indicative of metabolically active fungi, and Tri5 detection was significantly higher in 'Overley' compared with 'Overland'. Tri5 gene expression and DON concentrations showed little to no correlation; consequently, Tri5 expression levels did not accurately predict DON concentrations. The strobilurin did not significantly reduce Tri5 gene expression compared with untreated wheat. In the triazole treatment, a significant reduction in the relative expression of Tri5 was detected after 120 days, as well as a downregulation of Tri5 from 60 to 120 days of storage in 'Overley'. In grain from strobilurin-treated plots of both cultivars, the expression of Tri5 increased from 0 to 30 days after tempering. Genetic expression of Tri5 that is necessary for the production of DON can increase during storage of high-moisture grain. Fusarium fungi can persist in wheat kernels for several months postharvest and may actively produce toxin during this period.