Tomato Spotted Wilt VirusTomato Spotted Wilt VirusTomato Spotted Wilt Virus Tomato Spotted Wilt Virus and Thrips Managementand Thrips Management

Thomas TuriniThomas TuriniU i it f C lif i C ti E t iU i it f C lif i C ti E t iUniversity of California Cooperative ExtensionUniversity of California Cooperative Extension

Fresno CountyFresno County

Early symptoms of Beet curly top and Tomato spotted wilt on larger plants can be similar: dull green color and

curled leaves

Plant virusesPlant viruses

Thrips reported to transmit TSWVThrips reported to transmit TSWV

– Frankliniella occidentalis– F. schultzei– F. intonsa– F. fusca– F. bispinosa– Thrips tabaci– T. setosus– F. gemina– T. palmi

Western flower thripsFrankinella occidentalis

A E Whitfield D EA. E.Whitfield, D. E. Ullman, andT L. German. 2005. TOSPOVIRUS-THRIPS INTERACTIONS. Annu. Rev. Phytopathol. 2005. 43:459–89

TSWV must be acquired bybe acquired by the larvae to be transmissibletransmissible.

Western flowerWestern flower thrips develop through two

quiescent, non-feeding pupal stages in the

soil

Adults can live 30 to 45 days and transmit theand transmit the viruses to plants throughout their life.

XThe virus does NOT pass from female to eggs.

Fields Monitored 2007Fields Monitored 2007

*T*D T

*DT*

*D *TT

*TPepper*

2008 2008 MonitoredMonitoredMonitored Monitored FieldsFields

Cards were placed in fields weeklyCards were placed in fields weekly

10 flowers from 5 sites in each 10 flowers from 5 sites in each monitored field were collectedmonitored field were collectedmonitored field were collectedmonitored field were collected

The presence of TSWV can now be detected in thrips by RT-PCR: R Gilbertsonthrips by RT-PCR: R. Gilbertson

• Could help determine when virus-carrying thrips are presentT h i ll h ll i• Technically challenging

• Need to be able to tests thrips recovered from sticky cards

ThripsTomatoRadicchio Controls

(+) (-)

Marker

( ) ( )

775bp

Robert Gilbertson: UC Davis

Results-Thrips populations• Thrips populations begin to increase in March/April;p p p g p ;

peaked from May-July; and slowly declined until late fall(October) to winter when populations are lowest

• In 2007 populations were moderate whereas in 2008• In 2007, populations were moderate, whereas in 2008populations were twice to four-fold as high

• Detection of larvae in tomato flowers indicates thripsireproduction on tomato

• All were identified as western flower thrips

Insecticide for Control of ThripsInsecticide for Control of Thrips

– Thrips adults and immature stages generally p g g yprefer areas of the plant where they are sheltered (flower or bud tissues)Th i l i i idl– Thrips populations can increase very rapidly, 200-300 eggs/femaleInsecticide resistance is a concern– Insecticide resistance is a concern

– If specifically-timed insecticide application in host crops may reduce virus spreadost c ops ay educe us sp ead

– Carefully read label before making any pesticide recommendation.

Dimethoate 4EL 1pt

Radiant 6.0 fl ozThrips Counts Thrips Counts (4 days after (4 days after c

c20072007

Mustang 4.3 fl oz + Beleaf 50SG 2.8 oz

Lannate SP 1 lb

Dimethoate 4EL 1pt

treatment)treatment)c

c

c

Success 6.0 fl oz + Ecozin Plus 8.0 oz

Assail 30SG 4.0 oz

g c

abc

abc

Venom 70DG 4 oz

Success 6.0 fl oz abc

ab

Movento 5.0 oz

Mustang 4.3 fl oz abc

a

Untreated Control

Microthiol 6.0 lbs

All materials were applied on 1 Jun with

ab

a

0 5 10 15 20

thrips/10 flowers

ppInduce 0.25% v/v

Thrips Thrips Counts (4Counts (4

Dimethoate 4EL 1pt c20082008 Counts (4 Counts (4 days after days after treatment)treatment)

Radiant 6.0 fl oza

Mustang 4.3 fl oz + Beleaf 50 SG

bc

bc

treatment)treatment)Surround 25 lbs

Lannate SP 1 lb bc

bc

Baythroid XL 2 8 floz + Diazinon A

Leverage 5.1 fl oz

Mustang 4.3 fl oz abc

abc

b

Venom 70DG 4 oz

Movento 5.0 oz

Baythroid XL 2.8 floz Diazinon AG500 4 qts

ab

abc

ab

0 1 2 3 4 5

Untreated Control

Venom 70DG 4 oz

All t i l

ab

a

0 1 2 3 4 5

live thrips/10 shoots

All materials were applied on with Induce 0.25% v/v

Influence of Thrips Control P TSWV 2008Programs on TSWV, 2008

–H 9665 processing tomato direct–H 9665 processing tomato direct seeded and sprinkler irrigated on 9 AApr.

–Three replications , 3 Main plot p ptreatments, 4 sub plot treatments; 3 beds per main plot treatments–3 beds per main plot treatments

–75 ft sub plots

Main plot treatmentsp(pre-plant shank-applied

insecticide)insecticide)

1 Platin m 11 fl o1. Platinum 11 fl oz 2. Admire Pro 10.5 fl oz 3. Untreated

Sub-Plot Treatments (foliar insecticide applications)(foliar insecticide applications)

No. aps

19 May 28 May 5 Jun 13 Jun 24 Jun

5 Radiant 6.0 fl oz

Dimethoate 4EL 1pt + Mustang

Lannate WP 1lb

Radiant 6.0 fl oz

Dimethoate

Mustang 4.3 fl oz

3 Radiant Dimethoate Lannate WP X X3 Radiant Dimethoate + Mustang

Lannate WP X X

2 X Di th t L t WP X X2 X Dimethoate + Mustang

Lannate WP X X

0 Untreated Control

* Induce 0.25%

TSW-Symptom Incidence S il A li d I i idSoil-Applied Insecticide

7

5

6

(%)

4

5

ptom

s

Platinum 11 fl oz Admire Pro 10 5 fl oz

2

3

W-s

ym

Admire Pro 10.5 fl oz Untreated

0

1

2

TSW

0

TSW-Symptom Incidence F li A li d I i id PFoliar-Applied Insecticide Programs

10

89

10

(%) a

67

tom

s (

Five Three

b bb

345

W-s

ymp Three

Two None

123

TSW

01

Variety Response to TSWVVariety Response to TSWV

• Resistant Varieties: single dominantResistant Varieties: single dominant resistance gene – Sw-5 are available in both fresh market and processingboth fresh market and processing tomatoes (Tsw in peppers)

• Relative susceptibility of tomato varieties• Relative susceptibility of tomato varieties to TSWV

TSWV-Incidence in Mid-Season Processing T t V i ti t WSREC 2007Tomato Varieties at WSREC, 2007

25 AB 8058 (SW5)a

20

%)

( )HMX 5893H 9780ab

15

lant

s (

Sun 6368AB 2

bc

bcd

10

TSW

-pl

H 2506H 2601de

cdcd cd

cd

0

5T 60Red SpringH 2005e

0Variety

H 2005H 8004

TSWV-Incidence in Mid-Season Processing Tomato Varieties at WSREC, 2008

25AB 8058 (SW5)SUN 6368

aa

Transplanted 16 Apr

20

25

%)

SUN 6368H 2005AB 2b

15

20

ants

(%

AB 2H 9780PX 1723

b b

10

SW-p

la H 2601H 4007

c c

cdcd c

c

5

TS UG 4305NDM 5578NUN 672e

decde

0Variety

NUN 672HM 6898H 8004

e

TSWV-Incidence in Mid-Season Processing Tomato Varieties at WSREC, 2008

AB 8058 (SW5)ab a

ab

Transplanted 15 May

20

%)

UG 4305SUN 6368H 2005

abcabc

abc

abcd

abc

ab

15

ants

(%

H 2005H 4007PX 1723cde

bcd

abcd

10

SW-p

la NDM 5578H 9780def

cde

5TS AB 2HM 6898NUN 672f

ef

0Variety

NUN 672H 8004H 2601

f

TSWV-Incidence in Mid-Season Processing Tomato Varieties at WSREC, 2008

16 AB 8058 (SW5)SUN 6368

a

Direct Seeded 12 May

1214

%)

SUN 6368H 9780H 4007b

810

ants

(%

H 4007UG 4305H 2005

b

bc

68

SW-p

la AB 2PX 1723NUN 672de

cd cdcd

de d d

cd

24TS NUN 672

NDM 5578HM 6898e

dede de d

0Variety

HM 6898H 2601H 8004

e

IPM for TSWVIPM for TSWV

• Strategic planning of crops – avoidStrategic planning of crops avoid planting tomatoes near potential sources of TSWVof TSWV

• Use TSWV resistant varieties in high risk areasareas

• Sanitation – immediately plow under crop id f ll i h t d t lresidue following harvest, weed control

• Thrips/TSW-symptom monitoring -insecticide application at first indication of the virus

AcknowledgementsAcknowledgementsAcknowledgementsAcknowledgements

• CTRICTRI• Robert Gilbertson : Plant Path UC Davis

Di Ull E t l UC D i• Diane Ullman : Entomology UC Davis• Michelle Le Strange : UCCE Tulare• CTRI• Growers and PCAs in Fresno and KingsGrowers and PCAs in Fresno and Kings

Co.