Adam J. Silagyi, DPMState Survey CoordinatorFlorida CAPS

Huanglongbing (HLB) & the Asian Citrus PsyllidBiology, history in Florida and survey tactics

ObjectivesBiology of the Asian citrus psyllid (ASP).Biology of Huanglongbing (HLB).History of HLB & ACP in Florida.Survey history and tactics for both in

Florida.

Asian citrus psyllidDiaphorina citriKuwayama

Photo: Jeff Lotz, DPI

Biology of the ACP

Asian citrus psyllidDiaphorina citriKuwayama

Biology of the ACP

Adults about 2-3 mmWings have distinct

brownish bars on the top and bottom

Antennae with black tipCovered with whitish,

waxy secretionJumping will distinguish

them from sluggish aphids

Asian citrus psyllidDiaphorina citriKuwayama

Biology of the ACP

Photo: Jeff Lotz, DPIPhoto: Univ of FL

Asian citrus psyllidDiaphorina citriKuwayama

Biology of the ACP

Photo: Univ of FL

Nymphs are small and often difficult to see: (0.25 - 1.7 mm)

Color generally green to yellowish-orange with no abdominal spots

Psyllid nymphs have large wing pads.

Biology of the ACP

Psyllid eggs on petiole

Eggs are 0.3 mm long, elongated, football shaped.

Deposited on new flush with the long axis vertical to surface.

Color begins as pale then to yellow and finally to orange as they reach maturity.

Biology of the ACPFemales lay around 800 eggs during lifetime.Eggs laid on tips of new growth and between unfurling leaves.Eggs hatch in 2-4 days.Optimum developmental temperature 25-28 ºC.Five nymphal instars completed in 11-15 days.

Adult female and nymphal instars

Catling, 1970.

Biology of the ACPLife cycle from 15 to 47 days.Adults can live several months.Nine to 10 generations/year.No diapause

Adult female and nymphal instars

Catling, 1970.

Biology of the ACPLife cycle from 15 to 47 days.Adults can live several months.Nine to 10 generations/year.No diapause

Date1/1 3/1 5/1 7/1 9/1

0

10

20

30 Vero Beach

Mean number of adult psyllids per trap

0

10

20

30 Fort Pierce

Psyllids are found year round in Florida, however populations fluctuate. The graph to the right gives an example of peaking population levels through the year. USDA-ARS

Asian citrus psyllid damage

Photo: Susan Halbert, DPICitrus sp.

Asian citrus psyllids are restricted to citrus and closely related Rutaceae.

A preferred host is Murrayapaniculata (Orange Jasmine), an ornamental that is widely grown in southern Florida.

Asian citrus psyllid damageAsian citrus psyllids are

restricted to citrus and closely related Rutaceae.

A preferred host is Murrayapaniculata (Orange Jasmine), an ornamental that is widely grown in southern Florida.

Photo: Stephen M. Garnsey

Orange jasmine: Murraya paniculata

Asian citrus psyllid damage

Mason, 2005 Mason, 2005

Many times psyllids will not be present, but evidence of the feeding can still be found. The notch is a result of prior feeding by the psyllid.

Asian citrus psyllid damage

Photo: Susan Halbert, DPI

Large amounts of honeydew

Moderate amounts of leaf distortion

Notched and curled leaves

In dry weather observations of curled waxy secretions from nymphs

African citrus psyllid (Trioza erytreae)Only on Citrus and citrus relativesPossibly cause more direct damage than D. citri.Damage looks like early stages of scabNot in Western Hemisphere; yet!

Catling

and Annecke, 1968.

African citrus psyllidOnly on Citrus and citrus relativesPossibly cause more direct damage than D. citri.Damage looks like early stages of scabNot in Western Hemisphere; yet!

Photo: Stephen M. Garnsey

(Trioza erytreae)

African citrus psyllidOnly on Citrus and citrus relativesPossibly cause more direct damage than D. citri.Damage looks like early stages of scabNot in Western Hemisphere; yet!

Photo: Stephen M. Garnsey

Discovery of the Asian citrus psyllid

Ellen Tannehill, DPI Inspector

Discovery of the Asian citrus psyllid

After Asian citrus psyllid colonized SE Florida (red), it moved on Murraya paniculata to other counties very rapidly via the retail & discount nurseries industry.

D. citri now found all over the State.

Diaphorina citri hosts: (Adapted from Halbert and Manjunath, 2004)Diaphorina citri hosts: (Adapted from Halbert and Manjunath, 2004)Aegle marmelos (L.) Aeglopsis chevalieri SwingleAfraegle gabonensis Engl. Afraegle paniculata (Schaum.) Engl. Atalantia missionis Oliver Atalantia monophylla (L.) Corr. Atalantia sp. Balsamocitrus dawei Stapf Citropsis gilletiana Swingle & M. KellermanCitropsis schweinfurthii (Engl.)Swingle & Kellerm.Citrus aurantifolia (Christm.) Swingle Citrus aurantium L. Citrus deliciosa Tenore Citrus grandis (L.) Osbeck (C. maxima)Citrus hystrix DC. Citrus jambhiri LushingtonCitrus limon (L.) Burm. Citrus madurensis Loar. Citrus maxima (Burm.) Merr. Citrus medica L. Citrus meyeri Tan Citrus x nobilis Lour. Citrus obovoidea Hort. ex Tanaka cv ‘Kinkoji’Citrus x paradisi Macfad. Citrus reticulata Blanco Citrus sinensis (L.) Osbeck Aubert Citrus spp. Clausena anisum-olens Merrill Clausena excavata Burm

Clausena indica Oliver Clausena lansium (Lour.) Skeels Eremocitrus glauca (Lindley) Swingle Eremocitrus hybrid Fortunella crassifolia Swingle Fortunella margarita (Lour.) Swingle Fortunella polyandra (Ridley) Tanaka Fortunella spp.,Limonia acidissima L. Merrillia caloxylon (Ridley) Swingle Microcitrus australasica (F.J. Muell.) SwingleMicrocitrus australis (Planch.) Swingle Microcitrus papuana H.F. Winters Microcitrus sp. ‘Sidney’ Murraya exotica L. Murraya koenigii (L.) Sprengel Murraya paniculata (L.) Jack Naringi crenulata (Royb.) Nicholson Pamburus missionis (Wight) Swingle Poncirus trifoliata (L.) Raf. Severinia buxifolia (Poiret) Ten. Swinglea glutinosa (Blanco) Merr. Toddalia asiatica (L.) Lam Triphasia trifolia (Burm. f.) P. WilsonVepris lanceolata G. Don Zanthoxylum fagara (L.) Sarg..Apparent non-hosts:Casimiroa edulis Llave & Lex. Zanthoxylum clava-herculis LArtocarpus heterophyllus Lamarck - removed

Liberibacter hosts: (Adapted from Halbert and Manjunath, 2004)Liberibacter hosts: (Adapted from Halbert and Manjunath, 2004)

Aeglopsis chevalieri Swingle Atalantia missionis Oliver Balsamocitrus dawei Stapf. Calodendrum capensis Thunb. Catharanthus roseus (L.) G. DonX Citroncirus webberi J. Ingram & H. E. MooreCitrus amblycarpa Ochse Citrus aurantiifolia (Christm.) SwingleCitrus aurantium L. Citrus depressa Hayata Citrus grandis (L.) Osbeck Citrus hassaku Hort. ex Tanaka Citrus hystrix DC. Citrus ichangensis Swingle Citrus jambhiri Lushington Citrus junos Sieb. ex Tanaka Citrus kabuchi Hort. ex Tanaka Citrus limon (L.) Burm. Citrus × limonia Osbeck Citrus x nobilis Lour. ‘Ortanique’ Citrus maxima (pummelo/shaddock) Citrus x nobilis Lour.

Citrus oto Hort. ex Tanaka Citrus x paradisi Macfad. Citrus reticulata Blanco Citrus sinensis (L.) Osbeck Citrus sunki Hort. ex Tanaka Citrus unshiu (Mack.) Marc Clausena indica Oliver Clausena lansium (Lour.) Skeels Cuscuta australis R. Br. (Convolvulaceae, Cuscutaceae))Fortunella spp. Limonia acidissima L. Microcitrus australasica (F. J. Muell.) SwingleMurraya koenigii (L.) Murraya paniculata (L.) Jack Poncirus trifoliata (L.) Raf. Swinglea glutinosa (Blanco) Merr.Toddalia lanceolata Lam Triphasia trifolia (Burm. f.) P. WilsonPossible non-hosts:Citrus indica Tanaka Citrus limetta RissoCitrus macroptera Montrons

Movement of pathogen & vectorCitrus & ornamentals

Potted plants

Pot

Movement of pathogen & vectorCitrus & ornamentals

Potted plants

Flight distance???

Safe isolation distance for budwood production?

Movement of pathogen & vectorCitrus & ornamentals

Potted plants

Flight distance???

Safe isolation distance for budwood production?

Canker arc = 1900 ft or 260 acres

Psyllid arc* = 4750 ft or 1,627 acres (6.25x larger)

r=1900 ft

r=4750 ft

*Data based on African citrus psyllid

Biology of Huanglongbing

Symptoms of HLB in pummelo, Florida City

Biology of HuanglongbingCandidatus Liberibacter sp.

Candidatus L. africanusCandidatus L. asiaticusCandidatus L. americanus

Phloem-limited bacteriaNever cultured on artificial mediaCauses symptoms easily confused with abiotic disorders, i.e., nutrition.

Greening in commercial sweet orangePhoto: Susan Halbert

Biology of HuanglongbingAsian: warmer climates, transmitted primarily by Asian citrus psyllid (now in FL)African: cooler climates, transmitted primarily by African citrus psyllidAmerican: the third species was found in Brazil in 2004Both psyllids can transmit Asian and African greening.

Greening in commercial sweet orangePhoto: Susan Halbert

Psyllid feeds on infected citrus

for at least 15-30 min, feedin phloem tissues

Psyllids acquire bacteria

% of population carrying bacteria can be small, varies from

Often confused for HLB

Phytophthora foot rot

Mason

Iron (Fe) deficiency

Zinc (Zn) deficiencyMagnesium (Mg) deficiency

Manganese (Mn) deficiency

Potassium (K) deficiency

Often confused for HLB

Phytophthora foot rot

Ph

oto:

Su

san

Hal

bert

HLB in Florida in sour orange

Ph

oto:

Ph

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ason

Citrus greening symptomologyMottle that crosses veins in slightly older leaves

Photo: Susan Halbert, DPI

Citrus greening symptomologyMottle that crosses veins in slightly older leavesEarly symptoms differ from nutrient deficiencies with sectoring of branches

Infected branch

Healthybranches

Citrus greening in Florida lime

Citrus greening in Florida grapefruit

Photos: Susan Halbert

Citrus greening symptomologyMottle that crosses veins in slightly older leavesEarly symptoms differ from nutrient deficiencies with sectoring of branchesSmaller lopsided fruitOften with seed abortionPoor color poor taste

Citrus greening in Florida grapefruit

Photos: Susan Halbert

HLB in Brazil

Reported in Brazil July 2004C. L. asiaticus and americanusHave only D. citri

Fruit symptoms of HLB in Brazil

Photos: Jose Luiz Rodrigues

Discovery of HLBin Florida

2004 & 2005 focused on Tampa & Orlando areas using demographics.

Found August 2005 during a cooperative survey with CAPS, SITC and FDACS-DPI in South Florida.

Quickly launched a unified command of USDA-APHIS-PPQ and FDACS-DPI led Incident Command System (ICS).

HLB ICS ORGANIZATIONAL CHARTCOMMAND STAFF

Co-Incident CommandersM. Brodie – DPI

P. Hornby - USDA

OPS ChiefA. Silagyi – DPI

Planning ChiefT. Wright – DPI

Logistics ChiefJ. Head - USDA

PIOM. Fagan - DPI

Safety OfficerJ. McKee - USDA

IT SpecialistJ. Medina - USDA

Finance/Admin. ChiefS. Fitzgerald - USDA

Security SpecialistC. Lee - USDA

HLB ICS ORGANIZATIONAL CHARTHLB ICS ORGANIZATIONAL CHARTOPERATIONS SECTIONOPERATIONS SECTION

OPS ChiefAdam Silagyi – DPI

Residential SurveyBranch Dir.

E. Varona - USDA

Regulatory StrikeTeam Ldr.

D. Chisholm - DPI

IES Task Force Ldr.M. Conners - USDA

Grove SurveyBranch Dir.

J. Walker - DPI

Group A Supv.B. Saunders - USDA

Group A Supv.S. Mills - USDA

Group B Supv.D. Wolfe - DPI

Group B Supv.M. Meadows - DPI

Strike Team A

Strike Team B

Strike Team C

Strike Team D

Strike Team A

Strike Team B

Strike Team C

Strike Team D

Strike Team A

Strike Team B

Strike Team C

Strike Team D

Strike Team A

Strike Team B

Strike Team C

Strike Team D

Southeast Florida ICSSept 13 to Oct 14, 2005

••2,328 properties surveyed2,328 properties surveyed

••1361 samples taken 1361 samples taken

••179 positive trees179 positive trees

••156 positive properties in 156 positive properties in 80 80 TRS’sTRS’s

Discovery of HLBin Florida

Commercial Citrus Nursery Environ Survey

Nov 1 to Dec 16, 2005

Discovery of HLBin Florida

Commercial Citrus Nursery Environ Survey

Nov 1 to Dec 16, 20051,112 properties surveyed22,074 trees inspected156 TRS’s2 positive propertiesOne residential in

Highlands CountyOne commercial grove in

Desoto County

Discovery of HLBin Florida

Southwest Florida ICSJan 23 to Feb 17, 2006

RESEDENTIAL= 287 TRS’s= 1 positive TRS

GROVE= 305 TRS’s= 11 positive TRS’s= 31, 285 trees

Discovery of HLBin Florida

?

ArizonaD. citri not known to occur in ArizonaD. citri occurs in Texas and MexicoD. citri survives dry areas like Saudi Arabia and YemenSpread by D. citri and Humans (movement of infected material

and grafts)Look out for D. citri

Any psyllids in Citrus sp. are NOT goodRetail & discount stores

Hot Zones of interestAsian farms Demographics

ObjectivesAsian citrus psyllid�Diaphorina citri KuwayamaAsian citrus psyllid�Diaphorina citri KuwayamaAsian citrus psyllid�Diaphorina citri KuwayamaAsian citrus psyllid�Diaphorina citri KuwayamaAsian citrus psyllid damageAsian citrus psyllid damageAsian citrus psyllid damageAsian citrus psyllid damageAfrican citrus psyllid (Trioza erytreae)African citrus psyllidAfrican citrus psyllidDiaphorina citri hosts: (Adapted from Halbert and Manjunath, 2004)Liberibacter hosts: (Adapted from Halbert and Manjunath, 2004) Movement of pathogen & vectorMovement of pathogen & vectorMovement of pathogen & vectorBiology of HuanglongbingBiology of HuanglongbingBiology of HuanglongbingOften confused for HLBOften confused for HLBCitrus greening symptomologyCitrus greening symptomologyCitrus greening in Florida limeCitrus greening in Florida grapefruitCitrus greening symptomologyCitrus greening in Florida grapefruitFruit symptoms of HLB in BrazilHLB ICS ORGANIZATIONAL CHART�COMMAND STAFFArizona