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Poster: Diseases of Plants: Disease Detection & Diagnosis


Identification of genomics-based detection assay for Rhizoctonia solani anastomosis groups
T. MILES (1), J. Cerda (1) (1) CSU Monterey Bay, U.S.A.

Rhizoctonia is an important plant pathogen for many crops throughout the world causing plant tissue rot. Typically, diagnoses is accomplished using pure culture “tester” isolates and determining an anastomosis group. In order to develop new diagnostic tools, three mitochondrial genomes of Rhizoctonia solani were aligned with Mauve using the software Geneious 7.1. AG1 and AG3 had dramatically different mitochondrial genome sizes (160 Kb versus 250 Kb, respectively) due to the presence of introns. A region of the rRNA large subunit from the mitochondria was identified and several primers were designed. DNA was extracted from 5 isolates of R. solani followed by the polymerase chain reaction and sequencing. Sequence length for the large subunit of rRNA for each tested isolate varied significantly in size to what was expected. Difference in size is due to the presence and length of introns in the mitochondrial genome. Sequences were aligned for homology and differences. We are in the process of extracting purified genomic mitochondrial DNA from type isolates of R. solani to get a more complete picture of the significant diversity between AG groups. Even further research will be done to convert this method into a rapid field detection tool via recombinase polymerase amplification.