Project description:Biological control is a promising approach to control diseases caused by Pythium species. Unusually for a single genus, the Pythium genus also includes species that can antagonise Pythium plant pathogens, such as Pythium oligandrum. These Pythium plant pathogens are commonly found in the soil such as the broad host-range pathogen Pythium myriotylum and cause various diseases of important crops. While P. oligandrum genes expressed in the interaction with oomycete plant pathogens have been identified previously, the transcriptional response of an oomycete plant pathogen to P. oligandrum has not been investigated. An isolate of P. oligandrum, GAQ1, recovered from soil could antagonise P. myriotylum in a plate-based confrontation assay. The P. oligandrum isolate had a strong disease control effect on soft-rot of ginger caused by P. myriotylum. We investigated the transcriptional interaction between P. myriotylum and P. oligandrum. As part of the transcriptional response of P. myriotylum to the presence of P. oligandrum, putative effector genes such as a sub-set of Kazal-type protease inhibitors were strongly upregulated. P. myriotylum cellulases and elicitin-like putative effectors were also upregulated. In P. oligandrum, cellulases, peroxidases, proteases and NLP effectors were upregulated. The transcriptional response of P. myriotylum suggests clear features of a counter-attacking strategy that may contribute to the variable success and durability of biological attempts to control diseases caused by Pythium species. Whether aspects of this counter-attack could inhibit aspects of this virulence of P. myriotylum is another interesting aspect for future studies.
Project description:Contrary to the relative wealth of information regarding pathogen defense responses in aboveground plant parts, little is known about the mechanistic basis and regulation of plant immunity in root tissues. Aiming to further our fundamental understanding of root immune responses, we have investigated the interaction between rice and one of its major root pathogens, the oomycete Pythium graminicola. The specificic objectives of this study were twofold: i) to disentangle the molecular and genetic basis of the rice-Pythium interaction by comparing the transcriptome of rice roots at different times after inoculation with a highly virulent Pythium strains, and ii) to offer fundamental insights into the genetic architecture and regulation of rice disease resistance pathways operative in root tissue and to identify the molecular players controlling the possible nodes of convergence between these resistance conduits
Project description:Contrary to the relative wealth of information regarding pathogen defense responses in aboveground plant parts, little is known about the mechanistic basis and regulation of plant immunity in root tissues. Aiming to further our fundamental understanding of root immune responses, we have investigated the interaction between rice and one of its major root pathogens, the oomycete Pythium graminicola. The specificic objectives of this study were twofold: i) to disentangle the molecular and genetic basis of the rice-Pythium interaction by comparing the transcriptome of rice roots at different times after inoculation with a highly virulent Pythium strains, and ii) to offer fundamental insights into the genetic architecture and regulation of rice disease resistance pathways operative in root tissue and to identify the molecular players controlling the possible nodes of convergence between these resistance conduits Comparison between P. graminicola- and mock-infected rice roots. Two treatments (infected and non-infected) x three timepoints (1, 2 and 4 days post inoculation) x three biological replicates