A microscopic investigation of cochliobolous heterostrophous infection in maize
| Author(s) | Minker, Katharine Rita | |
| Date Accessioned | 2016-04-19T13:38:50Z | |
| Date Available | 2016-04-19T13:38:50Z | |
| Publication Date | 2015 | |
| Abstract | Maize is an important crop with a number of uses ranging from valuable food source to biofuel. It is afflicted, like many other grasses, by a number of different pathogens. Southern Leaf Blight (SLB) is a disease that leads to significant crop loss and subsequent negative economic impact worldwide. A number of methods are in place to protect crops against this disease and other related pathogens however the most practical and sustainable form of defense is natural resistance. Quantitative disease resistance (QDR), conditioned by multiple quantitative trait loci (QTL), is a durable form of genetic protection conditioned by multiple genes that offer varying contributions to disease resistance. The mechanisms by which each QTL can enhance the level of resistance is largely unknown. A more in depth understanding of each QTL is necessary for maize breeders to grow maize lines of superior resistance, taste, and quality. In this project, I developed a fluorescence microscopy method to investigate pathogenesis in order to characterize the mechanisms of QDR at a cellular level. Combining advances in fluorescence confocal microscopy with a new clearing and staining technique, I was able to visualize and quantify plant fungal interactions in three dimensions (3D) during a time course of disease progression. I began the investigation by comparing two inbred lines of maize with extreme differences in susceptibility. B73 and Mo17 were ranked 258th and 22nd in resistance to SLB respectively based on robust phenotyping of 309 maize lines. Image analysis that detects and measures the amount of fungal infection and features of the infection networks identified quantifiable differences between the two lines. Furthermore, the study of fungal pathogenesis revealed a heterogeneity of fungal penetration and a distribution of invasion or colonization mainly along the vascular tissue. In the future, these methods and features of pathogenesis will be used to examine nearly isogenic line (NIL) pairs contrasting for alleles at a single QTL to reveal clues about the mechanisms of genes for QDR. | en_US |
| Advisor | Caplan, Jeffrey L. | |
| Degree | M.S. | |
| Department | University of Delaware, Department of Biological Sciences | |
| Unique Identifier | 946934924 | |
| URL | http://udspace.udel.edu/handle/19716/17651 | |
| Publisher | University of Delaware | en_US |
| URI | http://search.proquest.com/docview/1767377994?accountid=10457 | |
| dc.subject.lcsh | Corn -- Disease and pest resistance -- Genetic aspects. | |
| dc.subject.lcsh | Cochliobolus. | |
| dc.subject.lcsh | Fluorescence microscopy. | |
| dc.subject.lcsh | Image analysis. | |
| Title | A microscopic investigation of cochliobolous heterostrophous infection in maize | en_US |
| Title | Mmicroscopic investigation of cochliobolus heterostrophus infection in maize | en_US |
| Type | Thesis | en_US |