Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


TSF - Dissertation Final (1).pdf (3.54 MB)

ETD Abstract Container

Abstract Header

An Investigation of The Role of Amino Acids in Plant-Plant Parasitic Nematode Chemotaxis and Infestation

Frey, Timothy S
http://rave.ohiolink.edu/etdc/view?acc_num=osu15659761481711

Abstract Details

2019, Doctor of Philosophy, Ohio State University, Plant Pathology.
Plant parasitic nematodes are economically devastating crop pests. They are responsible for billions of dollars in crop loss in all crop growing regions of the world. Management of these pests is difficult and involves many laborious, toxic or marginally effective measures that in the best of circumstances do not lead to complete control. Plant-parasitic nematodes are obligate biotrophic parasites and must obtain all of their nutrition from a living host. Plant parasitic nematodes lack the metabolic enzymes to synthesize certain amino acids, thus it is essential for them to obtain them from a plant. Because of the essential nature of amino acids for plant-parasitic nematodes the general aim of this study was to investigate their impact throughout nematode life cycles. This investigation examined the role of amino acids throughout the lifecycle of root-knot nematode, Meloidogyne incognita, and as a factor for chemotaxis of the sugar beet cyst nematode, Heterodera schactii, and the soybean cyst nematode, Heterodera glycines as well as the model nematode, Caenorhabditis elegans. The role of amino acids in M. incognita infestation was investigated using amino acid homeostasis knockouts and overexpression lines. Changes in threonine homeostasis, particularly in the threonine catabolism overexpression mutant 35s omr1-7 were found to lead to decreased early infestation, late infestation, fecundity and increased male production in M. incognita. These effects were particularly pronounced at higher competition levels. Threonine homeostasis is important for successful nematode infestation and manipulation of host amino acid homeostasis should be further explored for its impacts on M. incognita parasitism The role of amino acids in chemotaxis was investigated using choice assays. Threonine, aspartic acid, proline, and histidine were found to be the most attractive amino acids for M. incognita. Cysteine, phenylalanine and serine were the most repellant amino acids. The model nematode C. elegans showed different preferences for amino acids. Amino acids were present in soybean (Glycine max) root exudates, and a reconstructed blend of amino acids present in soybean root exudates was attractive to nematode species that can utilized soybean as a host, including M. incognita and H. glycines. These data could be utilized to create new integrated pest management strategies for nematode control.
Christopher Taylor, Dr. (Advisor)
Enrico Bonello, Dr. (Committee Member)
Soledad Benitez , Dr. (Committee Member)
Blakeslee Joshua, Dr. (Committee Member)
393 p.
Plant Pathology
Root-knot nematode; Amino acids; plant pathology; chemotaxis

Recommended Citations

Citations

  • Frey, T. S. (2019). An Investigation of The Role of Amino Acids in Plant-Plant Parasitic Nematode Chemotaxis and Infestation [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu15659761481711

    APA Style (7th edition)

  • Frey, Timothy. An Investigation of The Role of Amino Acids in Plant-Plant Parasitic Nematode Chemotaxis and Infestation. 2019. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu15659761481711.

    MLA Style (8th edition)

  • Frey, Timothy. "An Investigation of The Role of Amino Acids in Plant-Plant Parasitic Nematode Chemotaxis and Infestation." Doctoral dissertation, Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu15659761481711

    Chicago Manual of Style (17th edition)

osu15659761481711
823
© 2019, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.