Sandra Patussi Brammer
Brazilian Agricultural Research Corporation, Brazil
Title: Differential expression and identification of new adult plant resistance genes to leaf rust in Brazilian wheat cultivar Toropi
Biography
Biography: Sandra Patussi Brammer
Abstract
Wheat leaf rust, caused by Puccinia triticina, endemic of South America, it is an important wheat disease. The Brazilian wheat cultivar Toropi has proven, durable adult plant resistance (APR) to leaf rust and pre-haustorial resistance phenotype. The objective of this study was to identify, characterize and to understand the interaction between P. triticina and Toropi by quantitatively evaluating the temporal transcription genes related to infection and defense in wheat. RNA-Seq libraries from the Toropi here produced at 0, 6, 12, 24 hours after inoculation with P. triticina. Three replicates of each innoculated and control libraries were sequenced for each timepoint. A comparison to the Chinese Spring (CS42) transcriptome was performed aiming to identify putative genes unique to the Toropi. A total of 58 million bp per library were produced: 10,181 contigs of which 9,156 were common to CS42 and 1,025 were unique to Toropi expressed only in the inoculated libraries. The expression profiles of 15 selected genes varied over time. Classical defence genes, including peroxidases, b-1,3-glucanases and an endochitinase were expressed (pre and post-haustorial) over the 72 h infection time course, while induction of transcription of other infection-related genes with a potential role in defence, although variable was maintained through-out. These genes had a role in plant lignification, oxidative stress, the regulation of energy supply, water and lipid transport, and cell cycle regulation. These Toropi specific sequences could represent new resistance candidate genes to be used in wheat breeding and to guide further functional studies on APR to leaf rust.