Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Entire DC Network
Transgenic Control Of Aflatoxin Contamination In Maize Through Host-Induced Gene Silencing Targeting Aspergillus Flavus Genes Encoding Polygalacturonase (P2c) And Versicolorin Dehydrogenase (Aflm), Yenjit Raruang
LSU Doctoral Dissertations
Maize (Zea mays L.) is susceptible to Aspergillus flavus infection and subsequent contamination with aflatoxins, the most potent naturally produced carcinogenic secondary metabolites. Here, the A. flavus gene aflM encoding the versicolorin dehydrogenase in aflatoxin biosynthesis and the p2c gene encoding the polygalacturonase that is involved in infection were selected as targets for suppression through host induced gene silencing (HIGS). A HIGS vector targeting these genes was constructed and introduced into immature B104 maize embryos. Thirteen out of fifteen p2c transformation events and six out of seven aflM events were confirmed positive by PCR. Kernels containing the p2c gene …
Investigations Into Aspergillus Flavus Infection Of Corn And Regulation Of Aflatoxin Production By Volatiles And Biocontrol Strains, Rebecca R. Sweany
Investigations Into Aspergillus Flavus Infection Of Corn And Regulation Of Aflatoxin Production By Volatiles And Biocontrol Strains, Rebecca R. Sweany
LSU Doctoral Dissertations
Aspergillus flavus is an ascomycete fungus impacting agriculture, public and environmental health due to production of acutely-toxic, carcinogenic aflatoxins in oil seed crops, especially corn in Louisiana, and lung infections of immunocompromised patients resulting in a leading cause of AIDS patients’ deaths globally. The most effective aflatoxin mitigation strategy, biocontrol by atoxigenic A. flavus presents several concerns including: dissemination of a human pathogen, possible sexual reproduction and reliance on precise environmental conditions. Several aspects of A. flavus biology were investigated to potentially improve treatments. Studies investigated how genotypically diverse members within the A. flavus population interact with other population members …
Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda
Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda
LSU Master's Theses
Aspergillus flavus is a saprophytic ascomycete that can also actively invade the seed of crops and potentially contaminate them with harmful aflatoxins. Management of A. flavus currently relies mostly on biocontrol. However, there is still a lot to learn about its biology and ecology so the current approach can be improved. An A. flavus population survey was undertaken during the fall of 2014 across eight Mississippi River states to determine population diversity and geographic distribution of VCGs. Isolates from corn and soil were also characterized for VCG, sclerotial morphotype, mating type, cyclopiazonic acid, and aflatoxin production in order to determine …
Potential Roles Of Wrky Transcription Factors In Resistance To Aspergillus Flavus Colonization Of Immature Maize Kernels, Jake Clayton Fountain
Potential Roles Of Wrky Transcription Factors In Resistance To Aspergillus Flavus Colonization Of Immature Maize Kernels, Jake Clayton Fountain
LSU Master's Theses
The infection and colonization of maize (Zea mays L.) by the necrotrophic fungal pathogen Aspergillus flavus results in contamination of kernel tissues with carcinogenic mycotoxins known as aflatoxins, resulting in severe economic losses as well as negative effects on human and animal health. Resistance to A. flavus is mediated by both inducible and constitutively expressed defense proteins; however the mechanism regulating the expression of these defenses is poorly understood. This study examined the potential roles of six maize WRKY transcription factors, ZmWRKY19, ZmWRKY21, ZmWRKY53, ZmWRKY53.1, ZmWRKY67, and ZmWRKY68, in regulating defense responses against …
Mechanism Of Intraspecific Toxin Inhibition In Aspergillus Flavus, Changwei Huang
Mechanism Of Intraspecific Toxin Inhibition In Aspergillus Flavus, Changwei Huang
LSU Master's Theses
Atoxigenic Aspergillus flavus was demonstrated by others as a promising biocontrol agent to minimize preharvest aflatoxins in susceptible crops. But the mechanism was unclear. A filter insert-well plate system was used to study the mechanism in lab. There was no inhibition when toxigenic A. flavus isolate 53 and inhibitory atoxigenic isolates were separated by 0.4 µm membrane, approximately 50% inhibition occurred when separated by 12 µm membrane, and complete inhibition occurred when a 74 µm membrane was used. This result suggested that touching or close physical interaction is needed for toxin inhibition and the nutrient competition hypothesis was not supported. …