Updated on 20 June 2013
"Rice blast disease is a threat to global food security and it's closely related to wheat blast," Dr Valent said. "Because those two crops are the most important food staples worldwide, learning about these diseases is incredibly important," she added.
Researchers know that to cause plant diseases, pathogenic microorganisms secrete proteins, called effector proteins, into the host plant's tissue, Dr Valent said. The proteins suppress the plant's immunity and support the pathogen's growth. The goal of the study was to learn if fungi need different secretory systems to aid their invasion into host plants. "We knew that over time bacterial pathogens evolved multiple secretion systems to target effector proteins where they need to go. We didn't know whether fungi, which cause the major diseases in most crop plants, also require different secretory mechanisms," she said.
"In this study, we focused on investigating how the fungus secretes effectors during invasion of rice tissue by producing strains secreting effectors linked to fluorescent proteins from jellyfish and corals. We performed microscopy to watch the fungus secreting these fluorescent proteins as it grows inside rice cells, and we noticed that normal treatments that block protein secretion didn't stop those effectors that end up inside rice cells," Dr Valent said. "Identifying how these processes function will help us understand how disease microorganisms evolve and prove pivotal in controlling blast diseases," she said.