The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
-i \COMMON FUNGAL STEM ROT DISEASES OF FOLIAGE PLANTS
A. R. Chase I' 4. '5
IFAS, University of Florida
Agricultural Research Center-Apopka
ARC-A Research Report RH-81-4 -
.... iv o .
Diseases which occur primarily on plant stems are s m mes-less '
conspicuous than those occurring on the leaves. Since they can escape
notice longer and attack plant stems, they can cause more serious losses
than leafspot diseases and the key to control is prevention of infection.
Most stem rot organisms are soil-borne pathogens and should be controlled
in the soil. Avoid infecting plants by using sterile potting media, new
or clean pots and by growing plants on raised benches away from native
soil which harbors stem rot pathogens. Use pathogen-free stock when
possible since many of these diseases are spread through use of infected
stock plants. In-depth discussions of such control measures can be found
in previous Foliage Digest articles [2(3):16 and 3(10):13].
Stem rot of Dracaena sanderana is caused by Aspergillus niger.
Infection occurs on cutting bases before or during rooting and is typified
by wilting and yellowing of lower leaves. Stem bases become blackened and
watersoaked and the dark brown sooty fungal spores form there. Since this
organism lives in soil for long periods of time, use fresh potting media
for each crop. Using pathogen-free plants is recommended since spores can
be carried on the cuttings themselves. This disease also has been reported
on Sansevieria spp. showing similar symptoms. It is not common in Florida
since relatively cool temperatures restrict its development, but can be
seen on rooted cuttings shipped from the tropics where the temperature is
warmer on a year-round basis.
Ceratocystis blight of Syngonium podophyllum (black cane rot) is
caused by C. fimbriata. Symptoms include chlorosis of plants as well as
leafspots with chlorotic halos, dark brown stem lesions, and root rot
which can result in general plant chlorosis, Stem symptoms are most
noticeable and important in propagation beds where stems become brown to
black, watersoaked, and girdled. Avoidance of both overhead watering and
wounding plants can aid in control of this disease. This organism also
can be introduced through infected stock plants and care should be taken
to use pathogen-free plants at all times. Infected plants should be
removed to eliminate the source of disease spread.
The most important fungal disease of Thanksgiving cactus, also
called Christmas cactus (Schlumbergera truncata) is stem cladophylll) and
root rot caused by Fusarium oxysporum. Stem lesions are watersoaked and
have a reddish border. They may start at the soil line or above and are
orange colored if they begin on cladophylls well above the soil. Under
dry conditions the lesions appear dry. Orange to beige spores usually can
be seen in the midst of lesions and are readily carried from plant to
plant by numerous vectors including splashing water, human handling, and
insects, Keeping the soil moisture low is highly recommended. The most
important control method is use of pathogen-free plants and careful
handling of infected plants. Healthy plants should not be handled after
infected ones until hands are cleaned or clean gloves are worn,
Another stem disease caused by F. oxysporum and F. solani occurs on
Dieffenbachia maculata cultivars, especially 'Perfection' types. This
disease can cause losses in numerous ways including stem lesions formed
near the soil line or around aerial roots. Lesions are wet, mushy and
sunken and appear similar to those caused by Erwinia spp. However, in
Fusarium stem rot lesions usually are surrounded by a purplish margin.
Lesions also occur on cut ends of stock plants and may result in stem loss
by a rot extending from the cut surface into the plant base. Generally
the rot ceases to progress when it reaches the base of the stem. Reddish
petiole lesions forming in the tissue closest to the stem also are seen
when plants are watered from overhead. In severe lesions small bright red
fruiting bodies of the fungus appear. Control of this disease is based on
use of pathogen-free plants and sanitation. Since symptom similarities
between Fusarium stem rot and Erwinia blight are so great, diagnosis of
the disease prior to treatment is required.
Gliocladium stem rot of Chamaedorea spp. is the most important
disease of these plants. G. vermoeseni attacks leaf sheaths and stems and
is typified by dark brown spots (lesions). In severe infections, lesions
girdle the stem and kill plants. A gummy black secretion exudes from stem
lesions and pinkish-orange spore masses form in lesions. Spores are
transferred easily to healthy plants by the wind and splashing water.
Removal of lower leaves before they die creates wounds which admits the
spores and new infections begin. Avoidance of wounds and excessive
splashing during watering are recommended to decrease spread of
Gliocladium blight to healthy plants. Chrysalidocarpus lutescens (areca
palm) also has been reported as susceptible to this organism although it
rarely occurs naturally.
Helminthosporium stem rot is caused by H. cactivorum and is known to
occur on numerous species of cacti. The initial symptom is well defined
yellow spots which become brown with age. In advanced infections the stem
becomes black and rotten and may collapse. Under wet conditions the entire
cactus may become a watery mass. This disease can be important in seedling
beds and causes severe losses when plants are transferred to pots.
Infections usually occur through wounds and careful handling of small cacti
is important in minimizing losses. Use of sterile soil in seedling beds is
needed to avoid introduction through the soil.
Stem gall and cankers of Aphelandra squarrosa (zebra plant) and many
varieties of Codiaeum variegatum crotonn) is caused by Kutilakesa pironii.
Stem galls incited by this pathogen can reach 4.8 cm (2") in size on croton
and are roundish and corky. Galls may form where cuttings have been
removed and at leaf axils if the leaf has abscised. Symptoms on
aphelandras are similar. Since this fungus is an obligate wound pathogen
avoidance of wounding stock plants is recommended. Removal of infected
plants and use of pathogen-free stock is also important.
Sclerotium rolfsii causes a serious stem and leaf rot of Peperomia
obtusifolia and many other foliage plants. Symptoms of rot appear to be
most important in propagation beds where conditions for the spread of the
pathogen are ideal (warm and wet). Watersoaked cutting rot is followed
by a blackened mushy area frequently covered with the white growth of the
fungus and eventually with the brown seedlike fruiting bodies (Sclerotia).
Use of pathogen-free cuttings and the control measures mentioned in the
articles cited in the introduction are necessary to control this disease.
There are many other foliage plants which are susceptible to this organism
including philodendrons, dieffenbachias, palms, pothos, scheffleras and
syngoniums. Care should be taken to avoid infesting stock beds with this
organism since control through chemical applications is difficult in
planted beds and can result in phytotoxic reactions especially stunting.
Sterilization of infected stock beds prior to replanting is highly
desirable since the organism survives long periods of time in the form of
Diseases of foliage plants occurring on stems.
Host Disease Pathogen
Aphelandra squarrosa Aphelandra stem gall Kutilakesa pironii
stem rot H. cactivorum
Chamaedorea spp. Gliocladium blight G. vermoeseni
Codiaeum spp. stem gall and canker Kutilakesa pironfi
Dieffenbachia spp. Fusarium stem rot F. solani
Dracaena sanderana stem rot Aspergillus niger
Peperomia spp. and
many others Southern blight Sclerotium rolfsii
Sansevieria sp. stem rot Aspergillus niger
Schlumbergera truncata Fusarium stem rot F. oxysporum
Syngonium spp. black cane rot or
Ceratocystis blight C. fimbriata
1. Alfieri, S. A., Jr., and J. F. Knauss. 1972. Stem and leaf rot of
peperomia incited by Sclerotium rolfsii. Proc. Fla. State Hort. Soc.
2. Alfieri, S. A., Jr., J. F. Knauss, and C. Wehlburg. 1979. A stem gall-
and canker-inciting'fungus, new to the United States. Pl. Dis. Reptr.
3. Davis, L. H. 1953. Black cane rot of Syngonium auritum, Phytopath.
4. Durbin, R. D., L. H. Davis, and K. F. Baker. 1955. A Helminthosporium
stem rot of cactus. Phytopath. 45:509-512.
5. Miller, J. W. 1975. Blight and leafspot of Christmas cactus caused by
Fusarium oxysporum. Fla. Dept. Agric. & Cons. Ser. Div. Plant Ind,
Proc. Amer. Phytopath. Soc. 2:62.
6. Moorman, G. W. and R. A. Klemmer. 1980. Fusarium oxysporum causes basal
stem rot of Zygocactus truncatus. Pl. Dis. Reptr. 64(12):1118-1119.
7. Natour, R. M. and H. N. Miller. 1960, Stem rot of Dracaena sanderana.
Phytopath. 50:648. (Abstr.)
8. Reynolds, J. E. 1964. Gliocladium disease of palm in Dade County, Florida.
Pl. Dis. Reptr. 48:718-720.
9. Uchida, J. Y. and M. Aragaki. 1979. Ceratocystis blight of Syngonium
podophyllum. Pl. Dis. Reptr. 63:1053-1056.