December 2020 - 26

Studies target crippling tomato disease; prevention
By Brad Buck
University of Florida
A destructive disease known as
bacterial spot can ruin tomatoes
anywhere it strikes. That's why University
of Florida scientists want to understand
how the pathogen that causes the disease
spreads and evolves on farms.
A couple of quick statistics illustrate
the importance of tomatoes to Florida's
agricultural economic sector: Fresh
market tomatoes bring in $400 million
to $500 million annually in Florida,
according to the U.S. Department of
Agriculture. Further, UF/IFAS economists
reported tomato losses due to bacterial
spot of almost $900,000 in Florida in the
2007-08 growing season. Those are the
most recent dollar figures for the cost of
the disease to Florida tomatoes.
Erica Goss, an associate professor of
plant pathology at UF/IFAS, was awarded
a $455,000 grant by the National Institute
of Food and Agriculture, an arm of the
USDA, to study the epidemiology of
bacterial spot in tomatoes.
" Through this research, we hope to
more quickly and effectively respond to
changes in the bacterial spot pathogen
that cause more disease problems in the
field, " Goss said.
" We're studying epidemics. Plant
disease epidemiology does not often
include the possibility that the pathogen
how it changes - so they can keep track
of bacterial spot in tomatoes.
" We see lots of types of this pathogen
in Florida tomato fields, " Goss said.
" We are going to determine which types
of changes happen in the pathogen's
genome over the course of a tomatogrowing
season in a field. We are also
going to determine how specific changes
in the genome affect how the pathogen
moves from plant to plant during a given
season in a field. "
To find the problematic pathogen
strains, scientists will use highthroughput
genetic testing.
" We will send a genome-sequencing
center the extracted DNA from
hundreds of bacterial strains, and the
technology will send us data we can use
to study the genomes of these strains, "
Goss said.
Other UF/IFAS researchers will work
Scorched appearance of leaves at the bottom of the tomato canopy. Photo: Peter
Abrahamian, UF/IFAS
evolves within or between seasons, " said
Goss, who works at the main UF/IFAS
campus in Gainesville, Florida. " We are
going to look at the effect of pathogen
evolution - including the gain and loss
of genes that we have observed to have
occurred in Florida - on the spread of
the pathogen from plant to plant in a
given field. "
Bacterial spot of tomato is especially
severe in the southeastern United
States, where hot weather, high
humidity and rain can induce disease
development, according to a UF/IFAS
Extension document.
A pathogen called Xanthomonas
perforans, which constantly changes,
causes bacterial spot in Florida tomatoes.
Goss and her team want to find out
how quickly the pathogen changes - and
closely with Goss as she investigates
bacterial spot as an epidemic. They
include Gary Vallad, professor at the
UF/IFAS Gulf Coast Research and
Education Center in Balm (Hillsborough
County), Florida; Mathews Paret,
associate professor at the UF/IFAS
North Florida Research and Education
Center in Quincy, Florida; Jeff Jones,
distinguished professor at UF/IFAS in
Gainesville and Sujan Timilsina, a postdoctoral
researcher - all in the plant
pathology department at UF/IFAS. VGN
FIND OUT MORE AT AGBIOME.COM/HOWLER
©2020 AGBIOME, INC. ALL RIGHTS RESERVED. AGBIOME INNOVATIONS® IS A REGISTERED TRADEMARK OF AGBIOME INC.
AND HOWLER® IS A REGISTERED TRADEMARK OF AFS009 PLANT PROTECTION, INC. PRODUCT NOT YET REGISTERED IN HAWAII.
26 | VegetableGrowersNews.com

http://www.AGBIOME.COM/HOWLER http://www.VegetableGrowersNews.com

December 2020

Table of Contents for the Digital Edition of December 2020