Abstract:
Phytopathogenic fungi are a highly diverse group of
eukaryotes with significant impact on natural
ecosystems and cultivated lands, causing diseases on
crops, ornamentals and forest trees. Historical
outbreaks of invasive fungal pathogens on staple
crops have caused severe food security threats to
human populations. Therefore, accurate
identification of pathogenic fungi has a great impact
on global plant biosecurity and is considered to be
crucial in this era of global exchange of horticultural
products and plant germplasm. Although
morphological features have traditionally been used
in fungal identification, the past two decades have
witnessed revolutionary changes with the
implementation of DNA sequence data. The nuclear
ribosomal internal transcribed spacer region (ITS),
the standard fungal DNA barcode, is extensively
used for a quick and often approximate
identification. However, due to limitations of single
DNA barcodes in fungal species discrimination and
establishment of evolutionary relationships,
multiple genomic loci have been utilized. The
identification of fungi in plant biosecurity and
quarantine practices are often based on morphology
and tentative taxonomic assignments have increased
the risk to regional and global plant biosecurity. This
mini-review summarizes (1) the significance of
precise naming of pathogenic fungi; (2) the
incorporation of molecular data in the identification
of emerging phytopathogens with a few examples;
and (3) the need for paradigm shifts in global plant
biosecurity practices. In addition, we urge the
relevant agencies of the countries lacking organized
plant biosecurity practices to recognize the need to
confront the potential threats on their staple crops,
ornamentals and forest trees and support appropriate
research for DNA-aided identification and
classification, and application of accurate names to
high priority phytopathogens and emerging species.
This will enable effective disease surveillance,
prevent unnecessary trade restrictions for plantbased products and enhance biosecurity and
quarantine efforts
