Anthrancnose

Plant Disease
Aug. 2008
[slightly revised, May 2010]
PD-48 Mango Anthracnose
Published by the College of Tropical Agriculture and Human Resources (CTAHR) and issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation
with the U.S. Department of Agriculture. Andrew G. Hashimoto, Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mänoa, Honolulu, Hawai‘i 96822.
An equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, age, religion, color, national origin, ancestry, disability,
marital status, arrest and court record, sexual orientation, or status as a covered veteran. CTAHR publications can be found on the Web site <http://www.ctahr.hawaii.edu/freepubs>.
Mango anthracnose (Colletotrichum gloeosporiodes)
Dry weather during mango (Mangifera indica L.)
flowering seasons in Hawai‘i can stimulate the
formation of an enormous amount of mango blossoms
and indicates a potentially productive bearing season
ahead for mango growers. However, abundance of mango
flowering has happened before and yet the yields or
fruit quality were very disappointing, especially in wet
areas of mango cultivation. What are the explanations
for this?
First, most flowers in a mango panicle are male flowers
that do not yield fruit. The number of fruits produced
depends in part upon the number of hermaphrodite flowers
in the panicles, a number which varies among mango
cultivars.
Second, where mango flowering coincides with or is
the world. It is an important export crop in countries or
locations where quarantine pests and diseases can be controlled
satisfactorily. In Hawai‘i, mangos are commonly
eaten raw, dried when ripe, or pickled in condiments.
Demand for local mangos is very high in Hawai‘i when
the fruit is in season; good mango crops fetch premium
prices in the marketplace. Yet Hawai‘i’s mango production
could be significantly greater if anthracnose was not
such a major problem. Worldwide, mango anthracnose
is the most important and destructive disease of mango,
although in drier areas in Hawai‘i, mango powdery mildew
is probably the more harmful of the two diseases.
The host
Mango is in the plant family Anacardiaceae; related
Scot C. Nelson
Department of Plant and Environmental Protection Sciences
followed by wet weather, a devastating
disease known as anthracnose
can become established on panicles,
virtually destroying them. Or,
should the panicles make it through
the season without being destroyed
by anthracnose, the fruits produced
may still be seriously affected by
the disease when they are young,
and symptoms appear especially
during and after ripening of the infected,
mature fruit. (Compounding
this situation is the disease, mango
powdery mildew, which is covered
by another CTAHR Plant Disease
publication, PD-46.)
The mango tree produces a
delicious fruit that is widely consumed
in Hawai‘i and throughout
plants in this family include cashew
(Anacardium occidentale),
pistachio (Pistacia vera), and poison
ivy (Toxicodendron radicans).
Hundreds of mango cultivars are
known worldwide. Sometimes
called “the king of fruits,” mango
grows throughout the tropics and
subtropics and is regarded as one
of the world’s most important fruit
crops.
Mango is a perennial, branching,
evergreen tree approximately
30–40 feet tall. Its fruit is a large,
fleshy drupe containing a laterally
compressed stone housing the seed.
Mango cultivars vary considerably
in fruit size, color, shape, flavor,
texture, and taste. All photos by S. Nelson (unless noted otherwise)
UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
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The pathogen and disease symptoms
The ubiquitous fungus Colletotrichum gloeosporioides
Penz and Sacc. is the anamorph stage (asexual stage of
the pathogenic fungus). C. gloeosporiodes is responsible
for many diseases, also referred to as “anthracnose,” on
many tropical fruits including banana, avocado, papaya,
coffee, passion fruit, and others.
According to Ploetz (1999), “characterizations of
worldwide populations of C. gloeosporiodes indicate
that strains from mango comprise a genetically and
pathologically distinct population of this species. The
mango population of the pathogen always predominated
on mango, was not found on other tropical fruit crops,
and had a restricted host range insofar as individuals from
the population were highly virulent only on mango.” In
other words, populations of the pathogen are essentially
host-specific.
On mango, anthracnose symptoms occur on leaves,
twigs, petioles, flower clusters (panicles), and fruits. On
leaves, lesions start as small, angular, brown to black
spots that can enlarge to form extensive dead areas. The
lesions may drop out of leaves during dry weather. The
first symptoms on panicles are small black or dark-brown
spots, which can enlarge, coalesce, and kill the flowers
before fruits are produced, greatly reducing yield. Petioles,
twigs, and stems are also susceptible and develop the
typical black, expanding lesions found on fruits, leaves
and flowers.
Ripe fruits affected by anthracnose develop sunken,
prominent, dark brown to black decay spots before or
after picking. Fruits may drop from trees prematurely.
The fruit spots can and usually do coalesce and can
eventually penetrate deep into the fruit, resulting in extensive
fruit rotting. Most green fruit infections remain
latent and largely invisible until ripening. Thus fruits
that appear healthy at harvest can develop significant
anthracnose symptoms rapidly upon ripening. A second
symptom type on fruits consists of a “tear stain” symptom,
in which are linear necrotic regions on the fruit that
may or may not be associated with superficial cracking
of the epidermis, lending an “alligator skin” effect and
even causing fruits to develop wide, deep cracks in the
epidermis that extend into the pulp.
Lesions on stems and fruits may produce conspicuous,
pinkish-orange spore masses under wet conditions.
Wet, humid, warm weather conditions favor anthracnose
infections in the field. Warm, humid temperatures
favor postharvest anthracnose development.
Disease cycle
Dissemination: spores (conidia) of the pathogen are
dispersed passively by splashing rain or irrigation
water.
Inoculation: spores land on infection sites (panicles,
leaves, branch terminals).
Infection and pathogen development: on immature fruits
and young tissues, spores germinate and penetrate
through the cuticle and epidermis to ramify through
the tissues. On mature fruits, infections penetrate the
cuticle, but remain quiescent until ripening of the
climateric fruits begins.
Symptom and disease development: black, sunken, rapidly
expanding lesions develop on affected organs
Pathogen reproduction: sticky masses of conidia are
produced in fruiting bodies (acervuli) on symptomatic
tissue, especially during moist (rainy, humid) conditions.
Many cycles of disease can occur as the fungus
continues to multiply during the season.
Pathogen survival: the pathogen survives between seasons
on infected and defoliated branch terminals and
mature leaves
Integrated disease management practices
Management of mango anthracnose consists of five approaches:
• site selection
• cultivar selection
• cultural practices in the field (sanitation, plant spacing,
intercropping, etc)
• fungicide sprays in the field
• postharvest treatments (physical, chemical).
Table 1. Commercial mango production in Hawai‘i (2005).
Number of farms 100
Acreage in crop 295
Acreage harvested 190
Total number of trees 13,900
Number of bearing trees 8900
Utilized production 530,000 pounds
Farm price $1.11 per pound
Value of sales $586,000
Source: Hawai‘i Agricultural Statistics Service (2005); data are based
on mango farms participating in HASS’ annual survey and do not
reflect harvests from populations of naturalized mango trees or
those cultivated by backyard growers.
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UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
Table 2. Mango cultivar reaction to anthracnose (after Nishijima 1993).
Country Resistant Moderate Susceptible Very susceptible
Australia Carrie Kensington Pride Willard
Caraboa Florigon Neelum
Tommy Atkins Manaranijan
Saigon
Philippines Palmer Fernandin Carrie Ah Ping, Julie
Siam Arumanis Peter Passand Zill, Willard
Velei-Colomban Edward Cherakuruasa
Joe Welch Gedong Hingurakgoda
Tjenkir Kensington
Otts, Pope
Hawaii Paris, Fairchild Haden Exel Pirie
Rapoza
Florida Zill Haden Irwin, Sensation
Kent, Keitt
Tommy Atkins
The pathogen. Conidiogenesis in Colletototrichum gloeosporiodes (highly magnified) from mango in American Samoa. A
conidium (pl. conidia) is an asexual, nonmotile fungal spore that develops externally or is liberated from the cell that formed it.
Conidiogenesis is the formation of asexual spores (conidia or conidiopspores). A conidiophore is simple or branched hypha
on which conidia are produced. Photos: Fred Brooks
UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
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Panicle symptoms of mango anthracnose on various
mango cultivars in Hawai‘i and Micronesia. Infections appear
initially as tiny, well-defined black flecks or specks on
all tissues of the panicle. As the infection spreads, clusters of
flowers turn inky black and die. The panicle becomes prone
to nearly complete disintegration.
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UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
Mango anthracnose symptoms on fruits
Above, a basket of anthracnose-diseased mango fruits at a
farmer’s market in Hilo, Hawai‘i. Such fruits may be acceptable
for some lower-quality local markets but are certainly
not for shipping off-island. Development of the lesions occurs
within days from quiescent infections after the fruits begin to
ripen. Irregular, dark brown to black lesions form anywhere on
the fruit and often coalesce to form larger, severely blighted
areas. Lesions are somewhat depressed or sunken, initially
superficial but can penetrate deep into the flesh as disease
progresses. During humid or moist conditions, abundant orange-
brown to salmon colored spore masses of the pathogen
form in lesions on the fruit surface.
Symptoms of mango anthracnose on cultivar Rapoza: tan
colored centers and blackened margins.
On common mango and other mango types, two basic symptom
types for mango anthracnose are sunken black lesions
(above, left) or the “tear stain” effect (above right and below,
left), linear necrotic regions lending an alligator-skin effect,
often associated with cracking of the epidermis (below).
UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
6
Leaf symptoms
New mango leaves are most susceptible to infection, especially
when their emergence coincides with frequent rainfall.
Leaf lesions begin on these immature leaves as tiny brown
to black specks (above) which develop chlorotic halos (right).
Mature lesions on fully expanded leaves are dark brown and
often irregularly shaped, not vein delimited, and tending to
occur at leaf margins. The lesions can remain small under
most conditions, but can enlarge to create leaf blight where
relative humidity is high.
Choose a hot, dry area, and avoid wet areas. Practically
speaking, this means in Hawai‘i that one should
grow mango trees at lower elevations, on leeward sides of
islands, where rainfall is less than 15 inches per year.
Aside from site selection, the best way to manage
anthracnose is to plant a resistant cultivar.
Cultivars recommended for Hawai‘i
The following cultivars have been recommended by UHCTAHR
for Hawai‘i based on their horticultural properties:
Ah Ping, Fairchild, Gouveia, Harders, Keitt, Momi
K, Pope, and Rapoza. All of these cultivars are productive
and have superior quality fruit. Flowering occurs from
December to April in Hawai‘i, but off-season flowering
is common. Growers may have to use fungicide sprays
Table 3. Disease reactions of fruit of different mango
cultivars to anthracnose (adapted from Pernezny and
Ploetz 2000).
Disease reaction Cultivars
Highly susceptible Irwin, Kent
Susceptible Fascell, Haden, Palmer,
Sensation, Zill, Rapoza
Moderately resistant Carrie, Earlygold, Edward,
Florigon, Glenn, Julie,
Keitt, Tommy Atkins, Van Dyke
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UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
Stem, branch, and twig symptoms. Twig dieback occurs when severe, elongated, blackened lesions form on stems and
twigs die back apically. In these photos, abundant sporulation of the pathogen covers the most decomposed points of the
infection.
to control anthracnose and/or powdery mildew on these
varieties in some locations.
Cultural practices
Practice sanitation: prune trees yearly and remove fallen
plant debris from the ground.
Plant spacing: wider plant spacing will inhibit severe
epidemics.
Intercropping: interplanting mango with other types of
trees that are not hosts of mango anthracnose will inhibit
epidemics.
Chemical control
Control of anthracnose on very susceptible mango
cultivars and in very conducive environments requires
periodic fungicide sprays. The timing and frequency of
applications are very critical for adequate disease control.
Sprays should begin when panicles first appear and
continue at the recommended intervals until fruits are
about 11⁄2–2 inches long.
In Hawai‘i, a range of foliar fungicides are registered
for control of mango anthracnose, including products
containing clarified neem oil, mono- and di-potassium
UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
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salts of phosphorous acid, chlorothalonil, basic cupric
sulfate, copper hydroxide, wettable sulfur, harpin protein,
and copper salts of fatty and rosin acids. These products
vary in their mode of action and efficacy. Consult the
CTAHR Cooperative Extension Service for current
product names and specific recommendations.
Postharvest treatment
The following can retard or reduce symptom development:
Table 4. Some fungicides for sale in Hawai‘i* for control of mango anthracnose, Colletotrichum gloeosporiodes, and
Glomerella cingulata, the sexual stage of the pathgen.
Product name* Active ingredient Formulation
70% Neem oil Clarified hydrophobic neem oil (70%) Soluble concentrate
Agri-Fos Systemic Fungicide, Mono- and di-potassium salts of
Alude Systemic Fungicide phosphorous acid (45.8%) Emulsifiable concentrate
Basic Copper 53 Basic cupric sulfate (98%) Emulsifiable concentrate
Champ Formula 2 Flowable
Agricultural Fungicide/Bactericide Copper hydroxide (37.5%) Flowable concentrate
Champion Wettable Powder Copper hydroxide (77%) Wettable powder
Agricultural Fungicide
(also Champion WG)
Decco Salt No. 19 Thiabendazole (98.5%) Wettable powder
DuPont Kocide 101 Fungicide/Bactericide Copper hydroxide (77%) Wettable powder
(also Kocide 2000, Kocide 2000, (and other formulations)
Kocide 4.5 LF, Kocide DF)
Copper hydroxide (46.1%) Water dispersible granules
Echo 720 Turf and Ornamental Fungicide Chlorothalonil (54%) Emulsifiable concentrate
Messenger (For Home and Garden) Harpin protein (3%) Water dispersible granules
Nu-Cop 3L (also Nu-Cop 50 DF, Copper hydroxide (37.5%) Flowable Concentrate
Nu-Cop 50WP, Nu-Cop HB) (other concentrations available (and other formulations)
in other Nu-Cop products)
Prescription Treatment Brand Copper salts of fatty and Emulsifiable concentrate
Camelot Fungicide/Bactericide, rosin acids (58%)
Tenncop 5E Fungicide/Bactericide
Sonata Bacillus pumilis strain QST Emulsifiable concentrate
2808 (1.38%)
• Refrigerate: keep at 50°F (10°C), but do not chill fruits
before they are ripe or there may be chilling injury.
• Hot water dip: dip fruits for 15 minutes at about 120–
130°F (49–55°C), depending on variety. Contact the
CTAHR Cooperative Extension Service for details, and
always test a few fruits before treating large batches.
• Vapor heat, forced-air dry heat: apply for 3–6 hours
at various temperatures, depending on variety.
• Heated fungicide dips (aqueous): products and temperatures
may vary.
*Availability is subject to state pesticide registrations, which are subject to change. Information in the table is believed to be current as of
May, 2010. Source of information: Hawaii Pesticide Information Retrieval System (HPIRS, http://state.ceris.purdue.edu/doc/hi/statehi.html).
Always follow pesticide label instructions and allowances exactly; do not use more or less than the label rate. Consult the pesticide label
and the Hawai‘i Department of Agriculture for questions about product applications. Other product names with similar active ingredients
may not be displayed in this table; mention of a product here is not a recommendation of the product in preference to other products that
may also be labeled for the use and approved for sale in Hawai‘i.
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UH–CTAHR Mango Anthracnose (Colletotrichum gloeosporiodes) PD-48 — Aug. 2008
References
Arauz, L. F. 2000. Mango anthracnose: economic impact
and current options for integrated management. Plant
Disease 84:600–611.
Diaz-Sobac, R., L. Perez-Florez, and E.J. Vernon-Carter.
2000. Emulsion coatings control fruit fly and anthracnose
in mango (Mangifera indica cv. Manila).
Journal of Horticultural Science and Biotechnology
75:126–128.
Hamilton, R.A., C.L. Chia, and D.O. Evans. 1992.
Mango cultivars in Hawaii. University of Hawai‘i at
Mānoa, College of Tropical Agriculture and Human
Resources. Information text series no. 42. 7 p.
Nishijima, W. 1994. Mango diseases and their control.
p. 20–24 in: Proceedings: Conference on Mango in
awaii. March 9–11, 1993, University of Hawai‘i at
Mānoa, College of Tropical Agriculture and Human
Resources.
Pernezny, K., and R. Ploetz. 2000. Some common
diseases of mango in Florida. Florida Cooperative
Extension Service, Institute of Food and Agricultural
Sciences, University of Florida, PP-23.
Ploetz, R. 1994. Mango anthracnose. p. 35–36 in: R.C.
Ploetz, G.A. Zentmyer, W.T. Nishijima, K.G. Rohrbach,
and H.D. Ohr (eds.), Compendium of tropical
fruit diseases. The American Phytopathological Society,
Minneapolis, Minn.
Ploetz, R. 1999. Anthracnose: The most important disease
in much of the mango-producing world. p. 1–2
in: PLP News, The Newsletter of the Plant Pathology
Department, The University of Florida, Gainseville.
vol. 3, issue 9, September, 1999.
Tang, J., E. Mitcham, S. Wang, and S. Lurie (eds.). 2007.
Heat treatment for postharvest pest control: Theory
and practice. CAB International, Cambridge, Mass.
349 p.
Acknowledgments
Fred Brooks, UH-CTAHR, for photographs and review
of the manuscript; Brian Bushe, UH-CTAHR, for review
of the manuscript.

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