Study compares varieties of citrus with metabolomic and microbiome combinations

In a recent study, researchers have found how a deadly or incurable citrus greening disease or Huanglongbing (HLB) affects root systems.

It is the first research to compare two varieties of citrus using a combined metabolomics and microbiome approach and demonstrates that scion influences root microbial community composition and, to a lesser extent, the root metabolome.

The first report on the reaction to causal bacteria of two various varieties of citrus, Candidatus Liberibacter asiaticus, with its use of metabolomics and microbiome technologies, has recently been published.

Emily M.T. Padhi author of the study said: "Metabolomics is a cutting-edge field of study that provides snapshot information about the metabolism of living things, while microbiome studies provide valuable information about the microbial communities living in a particular ecological niche - some microbes are beneficial to the host, while others can be harmful."

Padhi and associates wanted to see how the root system of two varieties of citrus responded to HLB.

They collected roots from healthy and infected Lisbon lemon and Washington Navel orange trees grown in greenhouses at the same time and under the same conditions.

They found that both varieties experienced a reduction in root sugars and amino acids when exposed to HLB.

However, they also found differences. While the concentration of malic acid and quinic acid increased in the navel roots, they decreased in the lemon roots.

They also found that the beneficial bacteria Burkholderia increased substantially in navel plants but not in lemons, which contradicts previous studies.

There is evidence to suggest that the causal bacterium moves to the root system soon after a plant becomes infected.

A key strategy for preserving the health of an infected tree is root system management and research on different responses to HLB may help devise new variety-specific preventative and treatment measures.