TITLE:
Metabolomics Profile of Potato Tubers after Phosphite Treatment
AUTHORS:
Xingxi Gao, Steven Locke, Junzeng Zhang, Jyoti Joshi, Gefu Wang-Pruski
KEYWORDS:
Potato, Metabolomics, GC-MS, Phosphite, Phytophthora infestans
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.9 No.4,
March
28,
2018
ABSTRACT: Phosphite (Phi)-based fungicides are used to control
the oomycete Phytophthora infestans which causes late blight disease, the most devastating disease in potatoes. In order
to examine the effects of Phi-based fungicides on potato tubers through foliar
or post-harvest application, a metabolite profiling approach based on gas
chromatography coupled to mass spectrometry (GC-MS) has been established. A
total of 132 metabolites were detected using the GC-MS approach. Among these, 34 metabolites
were identified after normalization and annotated with a compound name with
standard mass spectral library. Metabolomic analysis of Phi-treated plants
showed significant differences in the levels of many metabolites especially
amino acids. Multivariate statistical approaches, such as principal component
analysis (PCA) and partial least squares discriminant analysis (PLS-DA), were
employed to explore the relationships between metabolites to detect group
differences. A good
discrimination between the control and the Phi-treated plants was observed,
which demonstrated that significant changes in the metabolite profile have been
caused by the two different Phi applications (foliar or post-harvest). This
finding suggests that the alteration of specific metabolite levels by
accumulation of Phi can lead to resistance against the pathogen.