|JOGI, ANSUYA - University Of Georgia|
|KERRY, JOHN - University Of Georgia|
|BRENNEMAN, TIMOTHY - University Of Georgia|
|LEEBENS-MACK, JAMES - University Of Georgia|
Submitted to: Microbiological Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/1/2015
Publication Date: 3/1/2016
Citation: Jogi, A., Kerry, J.W., Brenneman, T.B., Leebens-Mack, J.H., Gold, S.E. 2016. Identification of genes differentially expressed during early interactions between the stem rot fungus (Sclerotium rolfsii) and peanut (Arachis hypogaea) cultivars with increasing disease resistance levels. Microbiological Research. 184: 1-12. doi: 10.1016/j.micres.2015.11.003
Interpretive Summary: This study was designed to identify genes quantitatively correlated with disease resistance level in the peanut white mold early disease interaction. RNA sequencing was used to analyze gene expression 4 days after inoculating peanut plant stems with the pathogen. Approximately seventeen hundred genes were responsive to infection in the cultivars tested. However, only 39 of these genes showed linear correlation with increasing or decreasing cultivar resistance levels amongst the 4 cultivars.
Technical Abstract: Sclerotium rolfsii, a destructive soil-borne fungal pathogen causes stem rot of the cultivated peanut, Arachis hypogaea. This study aimed to identify differentially expressed genes associated with peanut resistance and fungal virulence. Four peanut cultivars (A100-32, Georgia Green, Ga-07W and York) with increasing resistance levels were inoculated with a virulent S. rolfsii strain to study the early plant-pathogen interaction. 454 sequencing was performed on RNAs from infected tissue collected at 4 days post inoculation, generating 225,793 high-quality reads. Normalized read counts and fold changes were calculated and statistical analysis used to identified differentially expressed genes. Several genes identified as differential in the RNA-seq experiment were selected based on functions of interest and real-time PCR employed to corroborate their differential expression. Expanding the analysis to include all four cultivars revealed a small but interesting set of genes showing colinearity between cultivar resistance and expression levels. This study identified a set of genes possibly related to pathogen response that may be useful marker assisted selection or transgenic disease control strategies. Additionally, a set of differentially expressed genes that have not been functionally characterized in peanut or other plants and warrant additional investigation were identified.