Mark A. Bernards

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In response to wounding, potato tubers generate reactive oxygen species (ROS) in association with suberization. Immediately following wounding, an initial burst of ROS occurs, reaching a maximum within 30 to 60 min. In addition to this initial oxidative burst, at least three other massive bursts occur at 42, 63 and 100 h post-wounding. These latter bursts(More)
Plant growth promoting bacteria (PGPB) are capable of significantly altering the growth phenotype of inoculated plants. Changes in growth phenotype are often attributed to the ability of PGPB to assimilate minerals and/or increase mineral uptake, leading to increased plant root growth. However, many PGPB are also capable of either synthesizing plant(More)
  • Mark Vangessel, Peter Sikkema, Aaron Hager, Dawn Nordby, Bob Hartzler, Mike Owen +19 others
  • 2007
This publication was reviewed and endorsed by the Glyphosate, Weeds, and Crops Group. Members are university weed scientists from major corn and soybean producing states who have been working on weed management in glyphosate-resistant cropping systems. To see other titles in the Glyphosate, Weeds, and Crops series, please visit the Purdue Extension(More)
This study examined the effect of dietary carotenoid availability on carotenoid and retinoid concentrations in the flesh, plasma, skin and eggs of female Chinook salmon Oncorhynchus tshawytscha. Carotenoid concentrations in all tissues were closely related to dietary availability. Early in the breeding season, carotenoids were stored primarily in the(More)
Total body astaxanthin and lipid concentrations in threespine stickleback (Gasterosteus aculeatus) collected from fall through the start of the breeding season were correlated; concentrations of each increased between fall and spring and decrease during the pre-breeding season. Individual tissues (skin, muscle, viscera, carcass, and gonads) showed a(More)
Suberin, a major constituent of the potato periderm, is known to promote the production of thaxtomins, the key virulence factors of the common scab-causing agent Streptomyces scabiei. In the present study, we speculated that suberin affected the production of glycosyl hydrolases, such as cellulases, by S. scabiei, and demonstrated that suberin promoted(More)
Positive-sense RNA viruses have a small genome with very limited coding capacity and are highly dependent on host components to fulfill their life cycle. Recent studies have suggested that DEAD-box RNA helicases play vital roles in many aspects of RNA metabolism. To explore the possible role of the RNA helicases in viral infection, we used the Turnip mosaic(More)
The chlorophyll fluorescence parameter Φ NO is an excellent metric for the non-destructive monitoring of disease progression, measured over a broad range of light intensities. The suitability of the slow induction chlorophyll fluorescence parameters Φ PSII, Φ NPQ, and Φ NO to monitor in vivo disease progression in a host-root pathogen pathosystem was(More)
A waterhemp population from southeast Nebraska has been confirmed to be resistant to 2-4-D. The resistant population is believed to be limited to a few fields. In 2009 we received a report of a warm season grass field with a waterhemp population that was no longer being controlled by 2,4-D. Seed from this field was collected in 2009 and 2010 and greenhouse(More)
In jawed vertebrates, genes of the major histocompatibility complex (MHC) play a key role in immunity by encoding cell-surface proteins that recognize and bind non-self antigens. High variability at MHC suggests that these loci may also function in social signalling such as mate choice and kin recognition. This requires that MHC genotype covaries with some(More)