A NEW TOMATO VIRUS IN FLORIDA

swfrec.ifas.ufl.edu

A NEW TOMATO VIRUS IN FLORIDA

A NEW TOMATO VIRUS

IN FLORIDA

Jane E. Polston

Dept. of Plant Pathology

Univ. of Florida


Plants with symptoms like this were

collected in Florida in 2012

Location Date No. Samples

Miami-Dade Co. March 15

Lee Co. April 12


These symptoms were similar to those of Groundnut

ringspot virus (GRSV) and Tomato spotted wilt virus (TSWV)

Foliage and

fruit from a

GRSVinfected

tomato

Photo: courtesy

Glades Crop

Care

Foliage and

fruit from a

TSWVinfected

tomato


Nucleoprotein

coat

Detection of Tospoviruses

3 RNA genome segments:

S RNA

M RNA

L RNA


We used 3 assays to identify the virus in necrotic plants:

1. ELISA - detects both GRSV and TCSV

- detects TSWV

2. PCR - broad spectrum primers that detect many Tospoviruses

specific primers for TSWV, GRSV, TCSV

1 2 TCSV

TSWV

3. Obtained sequences of the PCR amplified DNA from each

genome segment and compared them to published sequences


Sequences amplified from necrotic tomatoes were nearly

identical to those of Tomato chlorotic spot virus (TCSV)

Genomic

Segment

Percent Nucleotide Sequence Identity

TCSV TCSV GRSV-[L GM TS G] GRSV

S RNA 97% 98% 80% 84%

M RNA 98% 98% 99% 94-95%

L RNA 98-99% --- 83% ---

Size of PCR fragments:

S RNA 1408-1455 nt

M RNA 878 nt

L RNA 1532 nt


Previously, TCSV was only known in Brazil and Argentina

Florida – TCSV is present in Miami-Dade Co. and Lee Co.


Vegetable

Hosts

Ornamental

Hosts

Weed

Hosts

Common bean Pea Impatiens Amaranthus spp.

Cape gooseberry

(Physalis peruviana)

Peanut

Lilac tasselflower

(Emila sonchifolia)

Celery Pepper Lisianthus

Cowpea Potato Petunia

Escarole Tobacco

Gilo

(Solanum gilo)

Lettuce

Known Susceptible Hosts of TCSV

Tomato

Ornamental

tobacco

(Nicotiana glutinosa)

Common purslane

(Portulaca oleracea)

Fierce Thornapple

(Datura ferox)

Jimson weed

(Datura stramonium)

Lesser swine-cress

(Cornonopus didymus)


Vegetable

Hosts

Ornamental

Hosts

Weed

Hosts

Common bean Pea Impatiens Amaranthus spp.

Cape gooseberry

(Physalis peruviana)

Peanut

Lilac tasselflower

(Emila sonchifolia)

Celery Pepper Lisianthus

Cowpea Potato Petunia

Escarole Tobacco

Gilo

(Solanum gilo)

Lettuce

Known Susceptible Hosts of TCSV

Tomato

Ornamental

tobacco

(Nicotiana glutinosa)

Common purslane

(Portulaca oleracea)

Fierce Thornapple

(Datura ferox)

Jimson weed

(Datura stramonium)

Lesser swine-cress

(Cornonopus didymus)


Symptoms of TCSV from Florida in Peppers

Healthy TCSV 1 TCSV 11


TCSV is vectored by several species of thrips


Few of the thrips that can be found in Florida crops have

been tested for their ability to transmit TCSV

Thrips (20 plus spp. not shown) Ability to Transmit

Common Name Scientific Name TCSV TSWV

Tomato thrips

(Common blossom thrips)

Frankliniella schultzei

(dark form)

+ +

Western flower thrips Frankliniella occidentalis + +

Onion thrips Thrips tabaci - +

Florida flower thrips Frankliniella bispinosa +

Melon thrips Thrips palmi +

Red-banded thrips Selenothrips rubrocinctus

Tobacco thrips Frankliniella fusca +

Chili thrips Scirtothrips dorsalis -

Cuban-laurel thrips Gynaikothrips ficorum

Flower thrips Frankliniella tritici

Gladiolus thrips Thrips simplex

Greenhouse thrips Heliothrips haemorrhoidalis

Grain thrips Limothrips cerealium


Tomato thrips

Frankliniella schultzei

Western flower thrips

Frankliniella occidentalis


Thrips Transmission Efficiency

Scientific Name Common Name TCSV TSWV

Frankliniella

schultzei

(dark form)

Frankliniella

occidentalis

Tomato thrips 37.5% 13.7%

Western flower

thrips

27.6% 66.0%

Thrips tabaci Onion thrips 0.0% 9.8%

Frankliniella

schultzei

(light form)

Frankliniella

intonsa

TCSV is transmitted at different rates by

different thrips compared to TSWV

Common blossom

thrips

(Tomato thrips)

5.9% 2.3%

Flower thrips 0.7% 31.8%


Thrips Transmission Efficiency

Scientific Name Common Name TCSV TSWV

Frankliniella

schultzei

(dark form)

Frankliniella

occidentalis

Tomato thrips 37.5% 13.7%

Western flower

thrips

27.6% 66.0%

Thrips tabaci Onion thrips 0.0% 9.8%

Frankliniella

schultzei

(light form)

Frankliniella

intonsa

TCSV is transmitted at different rates by

different thrips compared to TSWV

Common blossom

thrips

(Tomato thrips)

5.9% 2.3%

Flower thrips 0.7% 31.8%


Mean no. adult tomato

thrips per 5 flowers

7

Bean

6

Tomato

5

4

3

2

1

0

Pepper

Cucumber

Squash

Populations of tomato thrips (F. schultzei) adults in

Homestead, FL have increased over the last few years

2005 2006 2007 2008 2009 2010 2011

Year

Data courtesy of D. Seal


Known Hosts:

Tomato thrips – a vector with a wide host range and

the ability to transmit several Tospoviruses

Vegetable Crops: beans (various), eggplant, lettuce, okra, onion,

peanut, peppers (various), pigeon pea, pumpkin, spinach, sweet

potato, tomato

Fiber Crops: cotton

Ornamental Crops: carnation, Japanese daisies, rose, thistle,

Other Crops: canola, coffee, sorghum, sunflower, tobacco

Dark form of F. schultzei known to transmit:

Tomato spotted wilt virus (TSWV)

Tomato chlorotic spot virus (TCSV)

Groundnut ringspot virus (GRSV)

Groundnut bud necrosis virus (GBNV)

Chrysanthemum stem necrosis virus (CSNV)


Transmission Cycle of TCSV and Tospoviruses

ACQUISITION IS BY IMMATURES TRANSMISSION IS BY ADULTS

CROPS,

WEEDS

CROPS,

WEEDS


RECOMMENDATIONS FOR

TSWV MANAGEMENT

Use UV reflective mulches and

barriers

Use TSWV resistant cultivars

(SW5 gene)


Studies in Brazil have shown

that the SW5 gene provides

resistance to TCSV

SW5 gene is present in a

wide range of cultivars


RECOMMENDATIONS FOR

TSWV MANAGEMENT

Use UV reflective mulches and

barriers

Use TSWV resistant cultivars

(SW5 gene)

Use pest management scouting

Use insecticides for suppression

of thrips adults and immatures to

reduce within field spread

Use SAR eliciting compound to

reduce symptom appearance

Use of optimal fertility


Summary

Tomato chlorotic spot virus (TCSV) is now present in Florida

The most efficient vector of TCSV is the tomato thrips followed

by the Western flower thrips

There is a lot we don’t know about TCSV

Until we have more specific information, recommendations for

management of TSWV are likely to be effective


Sample no 10


Figure 1

A

B

C


TCSV is transmitted by different thrips and at different efficiencies

than other tomato-infecting tospoviruses

Thrips Transmission Efficiency

Scientific Name Common Name TCSV TSWV GRSV

Frankliniella

schultzei

(dark form)

Frankliniella

occidentalis

Common

blossom thrips

(Tomato thrips)

Western flower

thrips

37.5% 13.7% 15.7%

27.6% 66.0% 10.2%

Thrips tabaci Onion thrips 0.0% 9.8% 0.0%

Frankliniella

schultzei

(light form)

Frankliniella

intonsa

Common

blossom thrips

(Tomato thrips)

5.9% 2.3% 0.0%

0.7% 31.8% 0.0%

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