A Compass for Citrus Canker Complexity

Linda WeinlandPeter WoodruffMargaret WatermanEthel Stanley* *consultant

Family Trees

Carlos Silva sipped his morning coffee in the shade of the orange and grapefruit trees in the yard. He had planted one at the birth of each of his children.

As he read the paper, Carlos was startled by the full-color map on the front page. His eyes moved quickly to the center of the map where he found his own home to be outside a yellow zone north of US 41 and east of NW 87th Ave.

• Yellow areas are 1900 ft canker zones.

• If your citrus tree is located in one of the yellow map areas it will likely be cut down by the state citrus-canker fighters.

• Ref: Miami Herald, July 26, 2001

http://www.citruscanker.com/canker0726map.gif

Family Trees

With a sigh of relief, Carlos looked down at the grapefruit he was peeling and wondered if the spots on it were a problem.

Dade County

http://www.nass.usda.gov/fl/gif/cprd0001.gif

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://doacs.state.fl.us/canker/images/canker-by-year.jpg

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://www.edrinc.com/edr-hurricane.jpg

http://www.escambia-emergency.com/images/hcanemap.jpg

http://www.fema.gov/nwz99/images/hurr0819.gif

CA

AZ

TX

FL

http://www.met.fsu.edu/explores/Tropical/atl2.htm l

Models and Simulations

• Epidemiology• Resistan• Biology

Workbench• Precision Farming• Fireblight• Web-HIPRE

A Complex Business

• Doreena Fiello wiped her sweaty face as she planted the last orange tree in the grove. With pride she looked up at the new sign. There was so much to think about, and no profits for several years.

Fiello Orchards

Organic Citrus

Established 2002

Susceptibility of several citrus varieties and rootstocks to Xac

http://doacs.state.fl.us/~pi/enpp/pathology/ckhost.html

Highly Susceptible Moderately Susceptible

Citrus x paradisi Macf., grapefruit C. sinensis (L.) Osbeck, sweet orange

C. aurantiifolia (Christ.) Swingle, Key lime C. aurantium L., sour orange

C. limettioides Tan., Palestine sweet lime C. limon (L.) Burm., lemon

Poncirus trifoliata (L.) Raf., trifoliate citrus C x tangelo J. Ingram & H.E. Moore, tangelo

Moderately Resistant Highly Resistant

C. reticulata Blanco, mandarin, tangerine C. medica L., citron

C. maxima (Burm.) Merr., pummeloX Citrofortunella microcarpa (Bunge)

Wijnands, calamondin

C. aurantiifolia (Christ.) Swingle, Person or Tahiti lime

Fortunella spp., kumquat

goat weed (Ageratum conyzoides L (non-citrus, India)

U.S. Orange Juice Imports

U.S. Citrus Juice Exports

Orange Production : 1991-2001

Orange Production – including 2002 projection

• Notice the dip in 1999

• Why?

Was it a hurricane in1998?

Web-HIPRE Hierachical Preference Analysis

(www.hipre.hut.fi)

A Complex Business

Doreena noticed some small moths flying among the trees. She caught one and stuffed it into a baggie to bring to the extension agent. If it was a citrus leaf miner they would have to take action, and soon.

Citrus Leaf Miner

http://primera.tamu.edu/citrus_entomology.htm

Larva

damage

moth

Citrus Leafminer Distribution

http://plant.cdfa.ca.gov/biocontrol/insects/citruspests/clm-in-citrus-may6-02.pdf

CLM damage

• Citrus Leaf Miner (CLM) feeds on new growth, defoliates when severe

• Most destructive to trees less than 4 years old, since they produce new growth throughout season

• Older trees new growth mainly in spring

• Detection by “scouting”

• CLM cannot withstand high, dry heat (CA)

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://primera.tamu.edu/citrus_leafminer_parasites.htm

Parasite, and its Egg on Citrus Leaf Miner Larva

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

http://www.imok.ufl.edu/plant/docs/canker_indian_river_2002.pdf

Up in the Air As the seat belt sign

turned off again, Lynn opened her laptop. She allowed herself one drink to offset her nervousness about the long flight and the ONSA meeting later that day.

As the flight attendant poured her screwdriver, her eyes caught the juice can label: "Contains orange juice from the U.S.A., Brazil and Mexico."

Without some agreement at her meeting in Sao Paulo, she expected that next year the label might not include “the U.S.A.”

A faster and smaller Brasilian TIGR

Xanthomonas axonopodis pathovars, HrpX gene, partial cds unrooted tree!

Phage genome map

• http://cancer.lbi.ic.unicamp.br/xanthomonas/citri/Maps/M2/1.1.html

Genetic control agent

Potential use of Aptamers binding to pathogenicity protein PthA (D.W. Gabriel, IFAS)

Cut one, the lace of acidRushes out, spills over your

hands.You lick them, manners don’t

come into it.

Orange – the first word you have heard that day – enters your mind…

- Mary Oliver, 2002