Kenneth Callicott

Dr. Kenneth Callicott

United States Department of Agriculture, Agricultural Research Service
orcid

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 December 2012 in Annals of the New York Academy of Sciences
Verified
Journal Article
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HMHillary Mehl
Hillary Mehl
RJRamon Jaime
Ramon Jaime
KCKenneth Callicott
Kenneth Callicott
CPClaudia Probst
Claudia Probst
NGNicholas P. Garber
Nicholas P. Garber
Peter CottyPeter Cotty
Peter Cotty

1 February 2020 in Plant Disease
Verified
Journal Article
Open access
LSL. A. Senghor
L. A. Senghor
AOAlejandro Ortega-Beltran
Alejandro Ortega-Beltran
JAJ. Atehnkeng
J. Atehnkeng
KCKenneth Callicott
Kenneth Callicott
Peter CottyPeter Cotty
Peter Cotty
Ranajit BandyopadhyayRanajit Bandyopadhyay
Ranajit Bandyopadhyay
Aflatoxin contamination of groundnut and maize infected by Aspergillus section Flavi fungi is common throughout Senegal. The use of biocontrol products containing atoxigenic Aspergillus flavus strains to reduce crop aflatoxin content has been successful in several regions, but no such products are available in Senegal. The biocontrol product Aflasafe SN01 was developed for use in Senegal. The four active ingredients of Aflasafe SN01 are atoxigenic A. flavus genotypes native to Senegal and distinct from active ingredients used in other biocontrol products. Efficacy tests on groundnut and maize in farmers’ fields were carried out in Senegal during the course of 5 years. Active ingredients were monitored with vegetative compatibility analyses. Significant (P < 0.05) displacement of aflatoxin producers occurred in all years, districts, and crops. In addition, crops from Aflasafe SN01-treated fields contained significantly (P < 0.05) fewer aflatoxins both at harvest and after storage. Most crops from treated fields contained aflatoxin concentrations permissible in both local and international markets. Results suggest that Aflasafe SN01 is an effective tool for aflatoxin mitigation in groundnut and maize. Large-scale use of Aflasafe SN01 should provide health, trade, and economic benefits for Senegal.[ ] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

1 September 2006 in Applied and Environmental Microbiology
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Journal Article
Closed access
KCKenneth Callicott
Kenneth Callicott
VFVala Friðriksdóttir
Vala Friðriksdóttir
JRJarle Reiersen
Jarle Reiersen
RLRuff Lowman
Ruff Lowman
JBJean-Robert Bisaillon
Jean-Robert Bisaillon
NSNorman J. Stern
Norman J. Stern
Campylobacter jejuni is a major cause of bacterial food-borne infection in the industrial world. There is evidence that C. jejuni is present in eggs and hatchery fluff, opening the possibility for vertical transmission from hens to progeny. Poultry operations in Iceland provide an excellent opportunity to study this possibility, since breeding flocks are established solely from eggs imported from grandparent flocks in Sweden. This leaves limited opportunity for grandparents and their progeny to share isolates through horizontal transmission. While Campylobacter was not detected in all grandparent flocks, 13 of the 16 egg import lots consisted of eggs gathered from one or more Campylobacter -positive grandparent flocks. No evidence of Campylobacter was found by PCR in any of the 10 relevant quarantine hatchery fluff samples examined, and no Campylobacter was isolated from the parent birds through 8 weeks, while they were still in quarantine rearing facilities. After the birds were moved to less biosecure rearing facilities, Campylobacter was isolated, and 29 alleles were observed among the 224 isolates studied. While three alleles were found in both Sweden and Iceland, in no case was the same allele found both in a particular grandparent flock and in its progeny. We could find no evidence for vertical transmission of Campylobacter to the approximately 60,000 progeny parent breeders that were hatched from eggs coming from Campylobacter -positive grandparent flocks. If vertical transmission is occurring, it is not a significant source for the contamination of chicken flocks with Campylobacter spp.

12 November 2011 in European Journal of Plant Pathology
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Journal Article
Closed access
PDF file
CPC. Probst
C. Probst
KCKenneth Callicott
Kenneth Callicott
Peter CottyPeter Cotty
Peter Cotty

27 November 2014 in Letters in Applied Microbiology
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Journal Article
Closed access
PDF file
KCKenneth Callicott
Kenneth Callicott
Peter CottyPeter Cotty
Peter Cotty

1 September 2021 in Plant Disease
Verified
Journal Article
Closed access
LALourena Arone-Maxwell
Lourena Arone-Maxwell
KCKenneth Callicott
Kenneth Callicott
Ranajit BandyopadhyayRanajit Bandyopadhyay
Ranajit Bandyopadhyay
HMHillary Mehl
Hillary Mehl
MOMarc Orbach
Marc Orbach
Peter CottyPeter Cotty
Peter Cotty
Aflatoxins are potent Aspergillus mycotoxins that contaminate food and feed, thereby impacting health and trade. Biopesticides with atoxigenic Aspergillus flavus isolates as active ingredients are used to reduce aflatoxin contamination in crops. The mechanism of aflatoxin biocontrol is primarily attributed to competitive exclusion but, sometimes, aflatoxin is reduced by greater amounts than can be explained by displacement of aflatoxin-producing fungi on the crop. Objectives of this study were to (i) evaluate the ability of atoxigenic A. flavus genotypes to degrade aflatoxin B1 (AFB1) and (ii) characterize impacts of temperature, time, and nutrient availability on AFB1 degradation by atoxigenic A. flavus. Aflatoxin-contaminated maize was inoculated with atoxigenic isolates in three separate experiments that included different atoxigenic genotypes, temperature, and time as variables. Atoxigenic genotypes varied in aflatoxin degradation but all degraded AFB1 >44% after 7 days at 30°C. The optimum temperature for AFB1 degradation was 25 to 30°C, which is similar to the optimum range for AFB1 production. In a time-course experiment, atoxigenics degraded 40% of AFB1 within 3 days, and 80% of aflatoxin was degraded by day 21. Atoxigenic isolates were able to degrade and utilize AFB1 as a sole carbon source in a chemically defined medium but quantities of AFB1 degraded declined as glucose concentrations increased. Degradation may be an additional mechanism through which atoxigenic A. flavus biocontrol products reduce aflatoxin contamination pre- or postharvest. Thus, selection of optimal atoxigenic active ingredients can include assessment of both competitive ability in agricultural fields and their ability to degrade aflatoxins.