Pineapple Diseases

Back to
Pineapple Page

Fig. 1

Wilted plants
caused by Phytophthora

Fig. 2

Rotten root system
caused by P. cinnamomi

Heart rot of pineapple (Ananas comosus) caused by Phytophthora cinnamomi

Fig. 3

Heart rot of pineapple (Ananas comosus) caused by P. cinnamomi

Pineapple Phytophthora

Fig. 4
Phytophthora parasitica causes soft rotting of the basal white leaf tissues

Back to
Pineapple Page

Pineapple Heart/Root Rot

Pineapple root rot may be caused by various Phytophthora and Pythium species which attack and destroy the root system. Symptoms include a reduction in plant growth, development of reddish colored leaves, browning of leaf margins, and plant decline and death. Primary control is to use disease-free planting material and avoid long periods of excessive soil moisture. These rot-causing organisms may spread through the main stem and infect developing fruit as well. ¹
Heart rot affects the basal leaf tissues and can rot fruit as well, while root rot causes root necrosis that, if left unaddressed, may lead to reduced crop yields and total crop failure. ³
Phytophthora root rot of pineapple caused by the pathogen Phytophthora cinnamomi causes rotting of roots and anthocyanescence (reddening or purplish coloration) of foliage. ³


Fig. 5	Fig. 6	Fig. 7

Fig. 5. Pineapple Phytophthora parasitica smooth cayenne-root rot, heart rot
Fig. 6. Pineapple P. parasitica left, thieloviopsis center, right, non wounded smooth cayenne
Fig. 7. Root rot of pineapple (Ananas comosus) caused by P. cinnamomi

Further Reading
Heart and Root Rots of Pineapple, University of Hawai'i ^pdf

Mealybug Wilt of Pineapple (MWP)

Pineapple wilt is a serious disease. Disease occurs only in association with a mealybug and a closterovirus (PMWaV). Mealybugs can transmit the virus. Neither the virus nor the mealybug alone incites mealybug wilt. The virus occurs in high frequency in some clones that are planted. Other clones have a lower frequency of virus infection. Mealybug wilt is controlled by controlling the ants that tend the mealybugs. An effective ant control program makes it possible for the mealybug to be kept under control by predation by natural enemies. Ant control costs usually are less than those incurred in controlling mealybugs. ²


Fig. 8	Fig. 9

Fig. 8. Pineapple: Mealybug wilt. Pathogen: Mealybug wilt virus
Fig. 9. Mealybug wilt of pineapple in Hawai'i

Further Reading
Closterovirus Infection and Mealybug Exposure Are Necessary for the Development of Mealybug Wilt of Pineapple Disease, University of Hawai'i ^pdf
Pineapple Mealybug, University of Florida ^pdf

Bibliography

¹Crane, Jonathan. "Pineapple Growing in the Florida Home Landscape." Horticultural Sciences Dept., UF/IFAS Extension, HS7, Original pub. 1975, Re-written Oct. 2006, Revised Nove. 2016, Reviewed Dec. 2019, AskIFAS, edis.ifas.ufl.edu/MG055. Accessed 3 Mar. 2017, 13 Apr. 2020, 4 Jan. 2024.
²Sether, D. M., and J. S. Hu. "Closterovirus Infection and Mealybug Exposure Are Necessary for the Development of Mealybug Wilt of Pineapple Disease." University of Hawai'i at Mānoa, Plant and Environmental Protection Sciences, Honolulu. 2 April 2002, ctahr.hawaii.edu. Accessed 28 Jan. 2014.
³ Green, James, and Scot Nelson. "Heart and Root Rots of Pineapple." University of Hawai'i at Mānoa, Plant and Environmental Protection Sciences, Honolulu, 2 April 2002, ctahr.hawaii.edu. Accessed 4 Fev. 2017.

Photographs

Fig.¹Nelson, Scot, C. "Foliar symptoms of root rot of pineapple (Ananas comosus) caused by the Phytophthora plant pathogen." Flickr, 2011, (CC BY-SA 2.0), www.flickr.com. Accessed 19 Dec. 2016.
Fig.²Nelson, Scot, C. "Root rot of pineapple (Ananas comosus) caused by Phytophthora cinnamomi." Flickr, 2011, (CC BY-SA 2.0), www.flickr.com. Accessed 3 Feb. 2017.
Fig. ^3,7 Nelson, Scot, C. "Heart rot of pineapple (Ananas comosus) caused by Phytophthora cinnamomi." Flickr, 2011, (CC BY-SA 2.0), www.flickr.com. Accessed 19 Dec. 2016.
Fig.^4,5Nelson, Scot, C. "Pineapple Phytophthora parasitica smooth cayenne-root rot, heart rot." University of Hawai'i at Manoa, 2012, Flickr, (CC BY-SA 2.0), www.flickr.com. Accessed 3 Feb. 2017.
Fig.⁶Nelson, Scot, C., and E. E. Trujillo. "Pineapple Phytophthora parasitica left, thieloviopsis center, ck right, non wounded smooth cayenne." Flickr, 2012, (CC BY-SA 2.0), www.flickr.com. Accessed 3 Feb. 2017.
Fig.⁸Nelson, Scot, C. "Pineapple: Mealybug wilt. Pathogen: Mealybug wilt virus." University of Hawai'i at Mānoa, Mealybug Wilt Virus album, 2014,Flickr, (CC BY-SA 2.0), www.flickr.com. Accessed 3 Feb. 2017.
Fig.⁹Nelson, Scot., John Hu. "Mealybug wilt of pineapple in Hawai'i." University of Hawai'i at Mānoa, Mealybug Wilt Virus album, 2012, Flickr, (CC BY-SA 2.0), www.flickr.com. Accessed 3 Feb. 2017.

Published 28 Jan. 2014 LR. Last update 4 Jan. 2024 LR