Researchers work to understand virus-prone garlic

University of Queensland researchers are working to understand why garlic crops can be infected with multiple viruses without their nutrition or taste being affected. In fact, viruses are so common in garlic that it would be difficult to find one that isn’t harbouring at least six viruses, and some garlic plants can be infected with 10 to 12 viruses at the same time.

The primary aim, through the doctorial work of Sari Nurulita, is to develop reliable virus detection tests that can be used to understand the virus’s interaction with yield. Previous work showed that some garlic could have yields three times higher than others — despite also being infected with the same viruses — so the researchers are keen to understand how infection with a virus may or may not impact the yield.

At the moment it doesn’t seem as though there is a direct correlation between a garlic crop being infected and its yield, but other factors may be responsible.

“We think maybe gene silencing is happening naturally in the plant,” said UQ plant virologist Associate Professor John Thomas. “It may depend on which virus gets the upper hand in a particular clove, or the order they are infected in. There are so many different possibilities and it’s not a simple matter.

“But we are going to look at absolute levels of virus to see whether we can determine if gene silencing is responsible.”

Image caption: Garlic in fields, side by side, showing different yield for each seed category. Image credit: Sari Nurulita.