Carambola Diseases

Carambola Diseases
Back to Carambola Page Fig. 1 Algal leaf spot of avocado (Persea americana) in Hilo, Hawai‘i, caused by Cephaleuros virescens Fig. 2 Algal leaf spot Fig. 3 Algal leaf spot Back to Carambola Page	Algal Leaf Spot (Fig. 1,2,3) (caused by Cephaleuros virescens) Reddish colored leaf spot diseases are caused by various fungi (Cercospora averrhoa, Corynespora cassiicola, Phomopsis sp., Gloesporium sp. and Phyllosticta sp.). Observations indicate that these leaf spot fungi are more common on environmentally stressed or nutritionally deficient trees and occur on older leaves that normally abscise (drop) during the winter and early spring. No control is necessary for these leaf spotting fungi. Twigs and limbs may be attacked by red alga (Cephaleuros virescens). Symptoms include rough, circular, greenish-grey or rusty-red areas and shoot dieback. Contact your local UF/IFAS Extension agent for current control of red alga. Further Reading Cephaleuros Species, the Plant-Parasitic Green Algae, University of Hawai'i at Mānoa ^pdf Anthracnose (caused by Colletotrichum gloeosporioides/Glomerella cingulata) Ripe fruit that is injured may be attacked by the fruit-rotting fungus (Colletotrichum gloeosporioides), which causes anthracnose. A superficial blackish discoloration on fruit ("sooty mold") caused by Gloeodes pomigena may be found on fruit surfaces. Generally, no control is warranted for these fruit diseases. Decline (caused by Pythium splendens) This fungus has recently been identified as the cause of a general tree decline. Signs of decline include loss of tree vigor, leaf drop and twig, shoot and root die-back. Trees also demonstrate reduced fruit production in terms of number and size. For more information and control measures, consult your County Agricultural Extension Agent.
Bibliography Crane, Jonathan, H. "Carambola Growing in the Florida Home Landscape." Horticultural Sciences Department, UF/IFAS Extension, HS12, Original pub. Aug. 1981, Revised Apr. 1994, Aug. 2005, May 2007, and Nov. 2016, Reviewed Dec. 2019, AskIFAS, edis.ifas.ufl.edu/mg269. Accessed 28 Jan. 2014, 6 Nov. 2020. Photographs Fig. ^1,2,3 Nelson, Scot. "Algal leaf spot of avocado (Persea americana) in Hilo, Hawai‘i, caused by Cephaleuros virescens." College of Tropical Agriculture and Human Resources, University of Hawai'i at Mānoa, Aug. 2008, CTAHR, ctahr.hawaii.edu. Accessed 28 Jan. 2014. Published 27 Dec. 2014 LR. Last update 3 Nov. 2021 LR

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Carambola Page

Fig. 1

Algal leaf spot of avocado (Persea americana) in Hilo, Hawai‘i, caused by Cephaleuros virescens

Fig. 2

Algal leaf spot

Algae leaf spot

Fig. 3

Algal leaf spot

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Carambola Page

Algal Leaf Spot (Fig. 1,2,3)
(caused by Cephaleuros virescens)

Reddish colored leaf spot diseases are caused by various fungi (Cercospora averrhoa, Corynespora cassiicola, Phomopsis sp., Gloesporium sp. and Phyllosticta sp.). Observations indicate that these leaf spot fungi are more common on environmentally stressed or nutritionally deficient trees and occur on older leaves that normally abscise (drop) during the winter and early spring. No control is necessary for these leaf spotting fungi.
Twigs and limbs may be attacked by red alga (Cephaleuros virescens). Symptoms include rough, circular, greenish-grey or rusty-red areas and shoot dieback. Contact your local UF/IFAS Extension agent for current control of red alga.

Further Reading
Cephaleuros Species, the Plant-Parasitic Green Algae, University of Hawai'i at Mānoa ^pdf

Anthracnose
(caused by Colletotrichum gloeosporioides/Glomerella cingulata)

Ripe fruit that is injured may be attacked by the fruit-rotting fungus (Colletotrichum gloeosporioides), which causes anthracnose. A superficial blackish discoloration on fruit ("sooty mold") caused by Gloeodes pomigena may be found on fruit surfaces. Generally, no control is warranted for these fruit diseases.

Decline
(caused by Pythium splendens)

This fungus has recently been identified as the cause of a general tree decline. Signs of decline include loss of tree vigor, leaf drop and twig, shoot and root die-back. Trees also demonstrate reduced fruit production in terms of number and size.
For more information and control measures, consult your County Agricultural Extension Agent.

Bibliography

Crane, Jonathan, H. "Carambola Growing in the Florida Home Landscape." Horticultural Sciences Department, UF/IFAS Extension, HS12, Original pub. Aug. 1981, Revised Apr. 1994, Aug. 2005, May 2007, and Nov. 2016, Reviewed Dec. 2019, AskIFAS, edis.ifas.ufl.edu/mg269. Accessed 28 Jan. 2014, 6 Nov. 2020.

Photographs

Fig. ^1,2,3 Nelson, Scot. "Algal leaf spot of avocado (Persea americana) in Hilo, Hawai‘i, caused by Cephaleuros virescens." College of Tropical Agriculture and Human Resources, University of Hawai'i at Mānoa, Aug. 2008, CTAHR, ctahr.hawaii.edu. Accessed 28 Jan. 2014.

Published 27 Dec. 2014 LR. Last update 3 Nov. 2021 LR