Asian Citrus Psyllid and Citrus Greening Disease

Asian Citrus Psyllid and Asian Citrus Psyllid and Citrus Greening DiseaseCitrus Greening Disease

A serious threat to FloridaA serious threat to Florida

Susan E. Halbert

Photos taken by DPI staff unless otherwise noted

This presentation will show you Asian This presentation will show you Asian citrus psyllid and citrus greening disease. citrus psyllid and citrus greening disease. The latter is a very serious disease of The latter is a very serious disease of citrus that is not found in the Western citrus that is not found in the Western Hemisphere.Hemisphere.You also will receive training on FloridaYou also will receive training on Florida’’s s citrus greening surveycitrus greening surveyFinally, you will learn to recognize the Finally, you will learn to recognize the African citrus psyllid, a vector of citrus African citrus psyllid, a vector of citrus greening disease that does not occur in greening disease that does not occur in Florida.Florida.

Asian citrus Asian citrus psyllidpsyllid Diaphorina Diaphorina citricitri KuwayamaKuwayama

Psílido asiático del cítrico

Asian citrus Asian citrus psyllid psyllid nymphnymph

Psílido asiático del cítrico

Asian citrus psyllid damageAsian citrus psyllid damage

Daño causado por el psílido asiático del cítrico

White curly White curly wax from wax from nymphs of nymphs of Asian citrus Asian citrus psyllidpsyllid

Cera blanca producida por el psílido asiático del cítrico

Asian citrus psyllid was found for the first time in the USA in Florida in 1998.

Asian citrus greening was found for the first time in the USA in Florida in 2005.

HomesteadHomesteadSeptember, September,

20052005

The first psyllid The first psyllid find in Florida was find in Florida was in a dooryard. We in a dooryard. We were surveying for were surveying for something else at something else at the time. The first the time. The first disease find was disease find was in the city of in the city of Homestead during Homestead during a survey.a survey. Ellen Tannehill, DPI Inspector

Enverdecimiento del cítrico: Enfermedad del dragón amarillo

In Asia, Asian In Asia, Asian citrus psyllid citrus psyllid transmits citrus transmits citrus greening disease. greening disease. The Chinese name The Chinese name of the disease is of the disease is ““huanglongbing,huanglongbing,”” or yellow dragon or yellow dragon disease.disease.

Citrus greening disease:Citrus greening disease:

Does not occur in the Western Hemisphere, except for recent find in southern FL (9-1-05).Occurs in Asia and Sub-Saharan Africa.Caused by phloem limited bacteria.Citrus greening may be the worst disease of citrus caused by a vectored pathogen.

Citrus greening is a Citrus greening is a devastating diseasedevastating disease

In areas where the disease is endemic, In areas where the disease is endemic, citrus trees live only for 6citrus trees live only for 6--8 years, and most 8 years, and most never bear usable fruit.never bear usable fruit.Fruit from infected plants has poor color Fruit from infected plants has poor color (hence the name greening) and bad flavor.(hence the name greening) and bad flavor.In some areas where citrus greening is In some areas where citrus greening is endemic, it is not longer economically endemic, it is not longer economically feasible to produce citrus.feasible to produce citrus.

Citrus greening disease Citrus greening disease symptomssymptoms

The next slides will show symptoms of The next slides will show symptoms of citrus greening disease, compared with citrus greening disease, compared with common citrus nutritional problems in common citrus nutritional problems in Florida. Examine the photos carefully so Florida. Examine the photos carefully so that you will recognize the symptoms of that you will recognize the symptoms of citrus greening if you see them.citrus greening if you see them.

Tree infected with greeningTree infected with greening

Arbol infectado por el enverdecimiento del cítrico

Photo: Stephen M. Garnsey

Note el color heterogéneo de las hojas

• Note mottle that crosses veins on slightly older leaves. This is the best symptom to look for.

• Newest leaves have apparent zinc deficiency

• Notch in leaf is due to feeding by Asian citrus psyllid, the vector of citrus greening pathogens.

Notch

Mottle

Nutritional mottle from Florida Nutritional mottle from Florida –– not greeningnot greening

Mottle between veins

Color heterogéneo causado por problema nutricional, no por la enfermedad del enverdecimiento del cítrico

Take some time to compare the two Take some time to compare the two previous slides so that you are sure to previous slides so that you are sure to recognize the difference between citrus recognize the difference between citrus greening symptoms and symptoms of greening symptoms and symptoms of Florida nutritional mottles.Florida nutritional mottles.More slides of citrus greening symptoms More slides of citrus greening symptoms follow.follow.

Citrus greening symptomsCitrus greening symptoms

Sintomas del enverdecimiento del cítrico

Advanced Advanced case of case of citrus citrus greeninggreening

Caso avanzado del enverdecimiento del cítricoPhoto: Stephen M. Garnsey

Early infection of citrus greening in Early infection of citrus greening in grapefruit. Note sectoring.grapefruit. Note sectoring.

Infección temprana del enverdecimiento del cítrico en toronja

Early symptoms of citrus greening differ from nutritional problems in that greening often affects only one large branch of a tree at first. If you notice sectoring , as in this photo, report it to your supervisor.

Infected branch

Healthy branches

Citrus greening inCitrus greening in grapefruitgrapefruit –– close close up of previous slideup of previous slide

Infección temprana del enverdecimiento del cítrico en toronja

Some unusual symptoms of Some unusual symptoms of citrus greening diseasecitrus greening disease

Síntomas no comunes del enverdecimiento del cítrico


Most fruit from infected trees Most fruit from infected trees aborts.aborts.

La mayoría de los frutos de los arboles infectados se caen.

Fruit symptoms of citrus greeningFruit symptoms of citrus greening

•Small, lopsided fruit•Seed abortion•Poor color•Poor taste

Síntomas en los frutos:

• Fruta pequeña e irregular

• Aborto de la semilla

• Color verdoso

• Mal sabor Photo: Stephen M. Garnsey

Survey is most Survey is most important.important.

Your job is critical Your job is critical to preventing to preventing establishment of establishment of citrus greening.citrus greening.

Inspecciones son lo mas importante.

Su trabajo es crítico para la prevención del establecimiento de la enfermedad del enverdecimiento del cítrico.

If citrus greening If citrus greening becomes becomes established, it established, it will be important will be important to prevent to prevent spread through spread through propagation.propagation.

Si se establece el enverdecimiento del cítrico, será importante prevenir que se extienda a travez de la propagación de árboles.

World distribution of citrus psyllids and citrus greening disease

Distribución mundial de los psílidos del cítrico y del enverdecimiento del cítrico

Citrus greening distributionCitrus greening distributionThere are two kinds of citrus greeningThere are two kinds of citrus greening

Asian Asian –– transmitted primarily by Asian citrus psyllidtransmitted primarily by Asian citrus psyllidAfrican African –– transmitted primarily by African citrus psyllidtransmitted primarily by African citrus psyllidBoth psyllids can transmit both pathogens.Both psyllids can transmit both pathogens.

African citrus greening occurs in Africa, south of the African citrus greening occurs in Africa, south of the Sahara.Sahara.Asian citrus greening occurs in Asia, west to Iran.Asian citrus greening occurs in Asia, west to Iran.Both forms occur in several islands in the Indian Both forms occur in several islands in the Indian Ocean and the Saudi Peninsula.Ocean and the Saudi Peninsula.No citrus greening occurs in the Western Hemisphere No citrus greening occurs in the Western Hemisphere (except initial find in Homestead, FL, 9/05); however, (except initial find in Homestead, FL, 9/05); however, Asian citrus psyllid occurs here.Asian citrus psyllid occurs here.

High risk areas for citrus greening in High risk areas for citrus greening in Florida:Florida:

Citrus greening is most likely to travel with Citrus greening is most likely to travel with infected plant materialinfected plant materialNeighborhoods where people from parts of the Neighborhoods where people from parts of the world that have citrus greening live are high world that have citrus greening live are high risk. Study the map to see where citrus risk. Study the map to see where citrus greening occurs.greening occurs.Remember that citrus greening occurs in Asia, Remember that citrus greening occurs in Asia, west to Iran, Subwest to Iran, Sub--Saharan Africa, the Saudi Saharan Africa, the Saudi peninsula, and in several islands in the Indian peninsula, and in several islands in the Indian Ocean.Ocean.

Citrus greening surveyCitrus greening survey

We always will have to survey in Florida We always will have to survey in Florida for citrus greening disease because we for citrus greening disease because we have the vector now.have the vector now.Survey and early detection is the most Survey and early detection is the most important first step in preventing important first step in preventing establishment of the diseaseestablishment of the disease

Citrus greening survey basicsCitrus greening survey basicsInspect sentinel trees (oranges or mandarins Inspect sentinel trees (oranges or mandarins best) in spring and fallbest) in spring and fallIf you cannot survey the entire area, If you cannot survey the entire area, concentrate on high risk locationsconcentrate on high risk locations

Ethnic communities with people from areas Ethnic communities with people from areas where citrus greening occurs (introduction risk)where citrus greening occurs (introduction risk)Areas near nurseries that distribute hosts of Areas near nurseries that distribute hosts of citrus greening or citrus psyllids (distribution risk)citrus greening or citrus psyllids (distribution risk)

African citrus psyllids African citrus psyllids –– not in not in the W. Hemispherethe W. Hemisphere

Psílido africano del cítrico – no se encuentra en Florida.

African citrus psyllids sit in depressions on the undersides of the leaves. The damage looks like an incipient scab infection from the top.


African African citrus citrus psyllid psyllid adult:adult: Note clear Note clear wingswings

Psílido africano del cítrico: Note las alas claras.


Eggs of Eggs of African African citrus citrus psyllidpsyllid

Huevos del psílido africano del cítrico Photo: Stephen M. Garnsey

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Asian Citrus Psyllid and Citrus Greening Disease