Eliminating Fusarium Mycotoxin Contamination of Corn by Targeting Fungal Mechanisms and Adaptations Conferring Fitness in Corn

<p>Objective 1: Determine the evolutionary history and molecular genetics of metabolic and developmental features enhancing the fitness of mycotoxigenic Fusarium (F.) species, including such areas as xenobiotic tolerance, denitrification, and nitric oxide detoxification and the contribution to greenhouse gas emission. Sub-objective 1.1 – Identify and characterize hydrolytic lactamases conferring adaptive advantages to F. verticillioides. Sub-objective 1.2 – Determine if F. verticillioides produces quorum sensing or quorum sensing inhibitory compounds in vitro and during endophytic colonization of corn. Sub-objective 1.3 – Evaluate denitrification by Fusarium species and its impact on competitive fitness, in planta production of mycotoxins, and the production of the potent greenhouse gas, nitrous oxide (N2O). Objective 2: Evaluate the influence of a common niche on the evolution and adaptation of two co-occurring, seed-borne, metabolically active maize endophytes, Acremonium (A.) zeae and Fusarium (F.) verticillioides. Sub-objective 2.1 – Utilize comparative genomics to determine if F. verticillioides and A. zeae share gene clusters or other features that correlate to corn as their common host. Sub-objective 2.2 – Evaluate competitive interactions between F. verticillioides and A. zeae and profile their transcriptional and metabolic responses. Objective 3: Develop and improve control strategies for mycotoxin contamination by targeting fungal-specific enzymatic activities, using molecular technologies such as host-induced gene silencing. Sub-objective 3.1 – Develop and express RNAi silencing constructs for in vitro growth inhibition of F. verticillioides. Sub-objective 3.2 – Develop and transform into corn functional vector(s) for host-induced gene silencing (HIGS). Sub-objective 3.3 – Testing transgenic corn lines for resistance to F. verticillioides.</p>