JE (José) Pacheco Díaz, MSc

Understanding the plant parasitic nematodes-virus interaction.

Plant parasitic nematodes (PPN) cause yield losses to diverse important crop species, and management measures are only partially successful. Recently, we discovered the first viruses that infect cyst nematodes which belong to the most damaging PPN in agriculture. The discovery of these PPN viruses opens novel research opportunities to understand and halt PPN. A critical step in this process is identifying how PPN respond to viruses. Here, we will study this viral response in the model cyst nematode Heterodera schachtii and the potato cyst nematode Globodera rostochiensis.

First, transmission routes and fitness effects will be tested for five viruses infecting H. schachtii and three viruses infecting G. rostochiensis. To this end, virus-free PPN populations will be selected or cleared from infection using antiviral drugs. Second, transmission routes and potential fitness effects of the viral infections will be tested using smFISH to understand virus cellular localization. Third, local antiviral responses will be studied using spatial transcriptomics to gain molecular PPN-virus insights. Finally, key genes in the antiviral RNAi pathway of PPN will be mapped by studying PPN strains with distinct antiviral RNAi profiles. Our preliminary data indicates variation in the antiviral RNAi response between two G. rostochiensis isolates. These two isolates carry genetically variable RNAi homologs of the model nematode C. elegans that will be the initial target genes. Together, this fundamental research into the molecular understanding of PPN-virus interactions will aid future research lines to use viruses for PPN gene delivery or in a biocontrol setting.