Author
CHIN, ELIZABETH - University Of California | |
MISHCHUK, DARYA - University Of California | |
Breksa, Andrew | |
SLUPSKY, CAROLYN - University Of California |
Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/24/2014 Publication Date: 7/16/2014 Citation: Chin, E., Mishchuk, D.O., Breksa III, A.P., Slupsky, C.M. 2014. Metabolite signature of Candidatus Liberibacter asiaticus infection in two citrus varieties. Journal of Agricultural and Food Chemistry. 62(28):6585-91. Interpretive Summary: The juice from healthy, HLB-asymptomatic, and HLB-symptomatic Hamlin and healthy and HLB-asymptomatic Valencia sweet oranges from different regions of Florida were evaluated with 1H NMR-based metabolomics. Comparisons of the composition of the juices revealed that certain metabolites had similar changes during infection in both orange varieties regardless of the tree’s growing region, but the rate at which the change occurred differed. This study expands the current understanding of the variations in tree response to HLB and how treatment and detection methods need to be tailored to specific tree types. To the best of our knowledge, this is the first study conducted in which the state of HLB infection, as well as varietal and regional differences were evaluated. Technical Abstract: Huanglongbing (HLB), also known as Citrus Greening Disease, is caused by the bacterium ‘Candidatus Liberibacter asiaticus’ (Las), and is severely damaging the citrus industry. Infection causes malformation of fruit, reduced fruit yields, discoloration of leaves, and twig dieback, eventually causing premature tree death. The juice from healthy, HLB-asymptomatic, and HLB-symptomatic Hamlin and healthy and HLB-asymptomatic Valencia sweet oranges from different regions of Florida were evaluated with 1H NMR-based metabolomics. Comparisons of the composition of the juices revealed that metabolites such as sucrose, phenylalanine, histidine, limonin, and synephrine had similar changes during infection in both orange varieties regardless of the tree’s growing region, but the rate at which the change occurred differed. Asymptomatic Valencia oranges were more similar in composition to symptomatic Hamlin oranges, suggesting that progression of the disease is accelerated in Valencia oranges, despite both cultivars being sweet orange types. This study expands the current understanding of the variations in tree response to HLB and how treatment and detection methods need to be tailored to specific tree types. |