Transcriptional profiling and effector identification of the Exserohilum turcicum-Zea mays interaction
M. HUMAN (1), O. Bezuidt (1), D. Berger (1), B. Crampton (1) (1) University of Pretoria, South Africa

Exserohilum turcicum is the causal agent of northern corn leaf blight, a yield-limiting foliar disease of maize. Monogenic resistance to E. turcicum is mediated by four major resistance (R) genes (Ht1, Ht2, Ht3 and HtN). The aims of this study were to identify highly expressed, novel effectors from E. turcicum and to investigate the transcriptional profiles of putative effectors across time points. Maize seedlings were inoculated with E. turcicum and samples collected prior to inoculation and during four stages of disease development. Transcriptome sequencing was performed and bioinformatics analyses of the resulting transcript sequences were used to characterize potential effector genes from the 100 most highly up-regulated transcripts at each disease stage. Putative effectors were predicted based on peptide size, secretion signal, absence of a transmembrane domain and lack of characterized function. In total, 43 predicted effectors were identified of which 24 were unique to a disease stage. Although 23 of the putative effectors showed peak expression at early stages of infection, two candidate effectors were up-regulated across all disease stages. Identification of effectors important to the pathogenicity of E. turcicum on maize will contribute to elucidation of the E. turcicum-maize interaction.

Abstract Number: P9-262
Session Type: Poster