Doi: 10. 1111/j. 1365-3059. 2007. 01608. x 2007 The Authors



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Key to species of Botryosphaeriaceae and their anamorphs from Syzygium cordatum in South Africa

1.  Fusoid to ellipsoid, thin-walled, Fusicoccum-like conidia...........................................................................................2

1.  Ovoid, thick-walled, Diplodia- or Lasiodiplodia-like conidia ....................................................................................3

2.  Colonies on MEA producing yellow pigment in young cultures.................................................................................4

2.  Colonies on MEA not producing yellow pigment in cultures .....................................................................................5

3. Conidia on average 



< 30 

µm long; aging conidia becoming dark brown with longitudinal striations and uniseptate as

reported by Punithalingam (1976)..................................................................................... Lasiodiplodia theobromae

3. Conidia on average 

> 30 

µm long, aging conidia become cinnamon to sepia with longitudinal striations and 1–3



septa................................................................................................................................................L. gonubiensis

4. Colonies producing amber-yellow pigment noticeable between 3–5 days after incubation; conidia on average 



< 20 

µm

long ......................................................................................................................................... Neofusicoccum luteum



Figure 4 Light micrographs of conidia of two Botryosphaeriaceae 

species with Lasiodiplodia anamorphs: (a) Lasiodiplodia gonubiensis

(b) L. theobromae. Bars 

= 10 


µm.

Plant Pathology (2007) 56, 624–636

Botryosphaeriaceae on Myrtaceae in South Africa

633


PPA_1608

4. Colonies producing honey-yellow pigment noticeable between 3–5 days after incubation; conidia on average 

> 20 

µm

long ............................................................................................................................................................ N. australe



5. Conidia on average 

> 25 


µm long, narrowly fusiform ..........................................................Botryosphaeria dothidea

5. Conidia on average 



< 25 

µm long..............................................................................................................................6

6. Conidia on average 

< 15 

µm long, l/w 2–2.5 ........................................................................................ N. mangiferae

6. Conidia on average 

≥ 15 


µm long, l/w 3–5 ................................................................................................................7

7. Conidia 15–27 

× 4–7 

µm, aseptate, fusiform, apices tapered ..........................................................................N. ribis



7. Conidia 13–25 

× 3.5–6 


µm, aseptate, fusiform to ellipsoid.........................................................................N. parvum

Pathogenicity

All Botryosphaeriaceae isolates tested for pathogenicity

on the E. grandis 

× camaldulensis clone (GC-540) produced

lesions within 6 weeks. No lesions developed on trees

inoculated with sterile MEA plugs as controls. The fungi

re-isolated from the lesions that developed on trees were

the same as those used for inoculations. The original

Botryosphaeriaceae species were re-isolated from all trees

chosen for re-isolations. No Botryosphaeriaceae were

re-isolated from the controls.

Statistical analyses showed that the mean lesion length

for the majority of isolates used in the trial differed

significantly from that of the controls (Fig. 5a). The longest

lesions were produced by isolates of L. theobromae, while

the size of lesions produced by B. dothidea and L. gonu-



biensis were not significantly different to those of the

controls (Fig. 5a). The mean lesion lengths for different

strains of the same Botryosphaeriaceae species were

not significantly different, except for the isolates of



L. theobromae. Thus, L. theobromae isolate CMW 14116

was significantly more pathogenic than isolate CMW

14114 (Fig. 5a).

All Botryosphaeriaceae isolates inoculated on S. cordatum

saplings produced lesions within 6 weeks. However, the

mean lesion lengths produced by majority of the isolates

were not significantly different from those of the controls

(Fig. 5b). Some trees inoculated as controls also developed

small lesions, but no Botryosphaeriaceae could be re-

isolated from these lesions, which appeared to represent

wound reactions. The fungi re-isolated from the lesions on

trees inoculated with fungal mycelium were the same as

those used for inoculations. The longest lesions were

produced by one isolate of N. mangiferae (CMW 14034)

and the mean lesion length obtained for this isolate was

significantly greater than that of the other isolate (CMW

14102) of the same species (Fig. 5b). However, there were

no statistically significant differences between the lesion

lengths for the different isolates of the other species of

Botryosphaeriaceae (Fig. 5b). The mean lengths of lesions

produced by one isolate of N. ribis (CMW 13992) and

one isolate of L. theobromae  (CMW 14116) were also

significantly different from that of the control (Fig. 5b).

All the other isolates inoculated onto S. cordatum saplings

produced lesions that were not significantly different from

those of the controls (Fig. 5b).

Isolates of all the Botryosphaeriaceae used in this study,

except those of N. mangiferuae, were more pathogenic on

the  Eucalyptus  clone than on S. cordatum. Analyses of

variance showed that the interactions between mean

lesion length produced by the species of Botryosphaer-

iaceae on the Eucalyptus clone and those on S. cordatum

were statistically significant (P 

≤ 0·001).



Discussion

Eight species of the Botryosphaeriaceae were identified on

native  S. cordatum  in South Africa in this study. They

Figure 5 Mean lesion lengths (mm) for each isolate of different species 

of the Botryosphaeriaceae 6 weeks after inoculations on (a) Eucalyptus 

grandis 

× camaldulensis clone GC-540 and (b) Syzygium cordatum

Bars represent 95% confidence limits for each isolate. C 

= Control; 



Botryosphaeria dothidea (CMW14009), Neofusicoccum parvum 

(CMW14097, 14030); N. ribis (CMW13992, 14031); N. australe 

(CMW13987, 14013); Lasiodiplodia theobromae (CMW14116, 14114); 

L. gonubiensis (CMW14077, 140780); Nmangiferae (CMW14102, 

14034); N. luteum (CMW14071, 14073).



Plant Pathology (2007) 56, 624–636

634


D. Pavlic et al.

PPA_1608

were N. ribis, N. parvum, N. luteum, N. australe, N. man-



giferae, B. dothideaL. theobromae and L. gonubiensis.

The isolates were identified based on ITS rDNA sequence

data, PCR-RFLP analysis and anamorph morphology.

With the exception of B. dothidea and L. gonubiensis, this

is the first report of all of these species of Botryosphaer-

iaceae on native S. cordatum. All eight species had the

ability to infect and cause lesions on the stems of a

E. grandis 

× camaldulensis clone and S. cordatum in glass-

house trials. Although lesions produced by most of the

isolates on S. cordatum saplings were not significantly

different from those on the controls, the pathogens could

be re-isolated from these lesions. In the case of some

species, such as N. ribis, L. theobromae and F. mangiferae,

one isolate did not produce lesions that differed from

those of the control, while the other isolate did. From

these data, and knowledge of the fungi on other hosts, it

was concluded that this group of fungi could be regarded

as potential pathogens of Syzygium. However, apart from

the isolates of B. dothidea  and  L. gonubiensis, all the

other Botryosphaeriaceae in this study produced lesions

on the Eucalyptus clone that were significantly different

from those of the controls. They should be considered as

potential threats to plantation grown Eucalyptus spp. in

South Africa.



Neofusicoccum ribis  was the dominant species

collected from native S. cordatum in South Africa in

this study. This fungus represented 38% of all isolates

obtained and was found in most of the areas surveyed.

This abundant and wide distribution on a native host

might indicate that this species is native to this region.



Neofusicoccum ribis has been reported from Eucalyptus

spp. (Myrtaceae) in its native range in Australia and on

non-native Eucalyptus spp. in plantations (Old & Davison,

2000), but has not been identified on Eucalyptus spp. in

South Africa (Slippers et al., 2004a). These identifications

should, however, be interpreted with caution, as the

distinction between N. parvum and N. ribis had not been

recognized at the time of these studies (Slippers et al.,

2004a). Furthermore, N. ribis as identified in this study

(using RFLPs) was also interpreted as representing the



N. ribis sensu lato group rather than strictly conspecific

populations with the type isolates of this species, as

identified by Slippers (2003). Further analyses using

sequence data for additional gene regions and other var-

iable markers will be required to more clearly characterize

populations and potential cryptic species in this group.



Neofusicoccum ribis  was one of the most pathogenic

species of the Botryosphaeriaceae on the Eucalyptus clone

in this study. This fungus should thus be considered as

a potentially important pathogen of Eucalyptus  spp. in

South Africa.

Isolates of N. parvum  represented 28% of the total

number of isolates obtained in this study. Recent studies

showed that N. parvum is an important and widely dis-

tributed pathogen of non-native Eucalyptus plantations in

South Africa (Slippers et al., 2004b). The wide distribution

of  N. parvum  on non-native and native Myrtaceae in

South Africa raises intriguing questions, such as whether

these populations are native or introduced and how they

might be interacting with each other. The movement

of this pathogen between these important host groups

represents a potential threat for both groups and should

be further investigated. Isolates of N. parvum used in this

study also developed only slightly smaller lesions than

those of closely related N. ribis, illustrating its potential

threat to Eucalyptus plantations in South Africa.

Only one isolate obtained from S. cordatum  was

identified as B. dothidea (anamorph Fusicoccum aesculi).

This species is one of the most commonly reported

members of the Botryosphaeriaceae from a wide variety

of hosts, including Eucalyptus spp. (von Arx & Muller,

1954; Smith et al., 2001). While B. dothidea was con-

sidered to be an important canker pathogen of Eucalyptus

spp. in South Africa (Smith et al., 1994), some of these

isolates that were the most pathogenic (Smith et al., 2001)

were re-identified as N. parvum (Slippers et al., 2004b).



Botryosphaeria dothidea  was seldom encountered on

Eucalyptus  spp. in other studies on this host (Slippers

et al., 2004b) and results of the present study suggest that

it is probably not an important pathogen of this tree.

High numbers of isolates from S. cordatum  were

identified as N. mangiferae. This species is best known

as a pathogen of mango (Mangifera indica) worldwide,

particularly in Australia (Johnson et al., 1992). Neofusic-



occum mangiferae  was earlier reported under different

names from mango in South Africa (Darvas, 1991).

Interestingly, however, a recent comprehensive study of

Botryosphaeriaceae from mango plantations in South

Africa, using a combination of DNA-based techniques and

morphological data, did not report this species (Jacobs,

2002). The fact that this fungus is highly pathogenic on

S. cordatum might imply that it has been introduced into

South Africa on other woody plants. Studies focused on

the origin of N. mangiferae are likely to yield intriguing

results, relevant to commercial forestry and to the pro-

tection of natural biodiversity in South Africa.

Neofusicoccum luteum  and phylogenetically closely

related N. australe were identified on S. cordatum in this

study, but have not been recorded on Eucalyptus spp.

in South Africa. Neofusicoccum australe  is a recently

described species (Slippers et al., 2004c) and the present

study is the first to consider the pathogenicity of this

fungus on Eucalyptus. Neofusicoccum luteum was highly

pathogenic to the Eucalyptus clone and its occurrence

on the related S. cordatum in South Africa is of concern.

Neofusicoccum luteum and N. australe were not the most

commonly encountered species of the Botryosphaeriaceae

on S. cordatum, but their presence alone provides sufficient

evidence that they are well established in the country.

Two Lasiodiplodia species were identified in this study.

Lasiodiplodia theobromae was isolated from S. cordatum

in subtropical areas of South Africa. This fungus is an

opportunistic pathogen with an extremely wide host

range, including more than 500 host plants, mostly in

tropical and subtropical regions (Punithalingam, 1976), and

has previously been isolated from exotic AcaciaEucalyptus

and  Pinus  spp. in South Africa (Crous et al., 2000;


Plant Pathology (2007) 56, 624–636

Botryosphaeriaceae on Myrtaceae in South Africa

635


PPA_1608

Burgess et al., 2003). Lasiodiplodia theobromae was the

most pathogenic species to the Eucalyptus  clone in

this study. Although the two isolates of L. theobromae

displayed different levels of pathogenicity, both were

highly pathogenic. Lasiodiplodia theobromae  might be

considered a potentially important pathogen of Eucalyptus

in South Africa and studies to consider its pathogenicity to

different species and hybrid clones would be warranted.

Another Lasiodiplodia species isolated from S. cordatum

was recently described as L. gonubiensis  (Pavlic  et al.,

2004) and was isolated from a geographical region with

a moderate climate where L. theobromae  was absent.

Lasiodiplodia gonubiensis was only very mildly pathogenic

to the Eucalyptus  clone, even though it is most closely

related to the highly pathogenic L. theobromae.

The results of this study provide an interesting insight

into the diversity of Botryosphaeriaceae occuring on

native S. cordatum in South Africa. Some of these fungi

appear to be potentially important pathogens of Eucalyp-

tus  spp. and future surveys should recognize this fact.

Clearly, additional studies such as the one presented here,

considering the pathogenicity of these fungi, will be

needed to better understand their importance. This study

emphasises the threat of cross-infecting species of the

Botryosphaeriaceae to both native and introduced

Myrtaceae. In a recent study, Burgess et al. (2006) showed

that there is no restriction to the movement of N. australe

between native and planted eucalypts in Western

Australia. Population studies on other species of the

Botryosphaeriaceae are, therefore, planned to provide

further insight into their movement between native and

cultivated hosts in South Africa.

Acknowledgements

We  thank the National Research Foundation (NRF),

members of the Tree Protection Co-operative Programme

(TPCP), the THRIP initiative of the Department of

Trade and Industry, and the Department of Science and

Technology (DST)/NRF Centre of Excellence in Tree

Health Biotechnology (CTHB), South Africa for financial

support. We also thank Dr B. E. Eisenberg who provided

the statistical analyses.

References

Anonymous, 2002. Commercial Timber Resources and 



Roundwood Processing in South Africa 2000 / 2001. South 

Africa: Forestry Economics Services.

von Arx JA, Müller E, 1954. Die Gattungen der amerosporen 

Pyrenomyceten. Beiträge zur Kryptogamenflora der Schweiz 



11, 1–434.

Burgess T, Wingfield MJ, 2001. Impact of fungal pathogens in 

natural forests ecosystems: a focus on Eucalyptus. In: Burgess 

T, Wingfield MJ, eds. Microorganisms in Plant Conservation 



and Biodiversity. Dordrecht, the Netherlands: Kluwer 

Academic Press, 285–306.

Burgess T, Wingfield MJ, Wingfield BD, 2003. Development and 

characterization of microsatellite loci for tropical tree 

pathogen Botryosphaeria rhodinaMolecular Ecology Notes 

3, 91–4.

Burgess T, Sakalidis M, Hardy GEStJ, 2006. Gene flow of the 

canker pathogen Botryosphaeria australis between 

Eucalyptus globulus plantations and native eucalypt forests in 

Western Australia. Austral Ecology 3, 559–66.

Coutinho TA, Wingfield MJ, Alfenas AC, Crous PW, 1998. 

Eucalyptus rust: a disease with the potential for serious 

international implications. Plant Disease 82, 819–25.

Crous PW, Phillips AJL, Baxter AP, 2000. Phytopathogenic 

Fungi from South Africa. Stellenbosch, South Africa: 

University of Stellenbosch Department of Plant Pathology 

Press.

Crous PW, Slippers B, Wingfield MJ et al., 2006. Phylogenetic 



lineages in the BotryosphaeriaceaeStudies in Mycology 

55, 239–57.

Darvas JM, 1991. Dothiorella dominicana, a new mango 

pathogen in South Africa. Phytophylactica 23, 295–8.

Denman S, Crous PW, Taylor JE, Kang JC, Pascoe I, 

Wingfield MJ, 2000. An overview of the taxonomic history of 

Botryosphaeria and a re-evaluation of its anamorphs based on 

morphology and ITS rDNA phylogeny. Studies in Mycology 



45, 129–40.

Felsenstein J, 1985. Confidence intervals on phylogenetics: an 

approach using bootstrap. Evolution 39, 783–91.

Fisher PJ, Petrini O, Sutton BC, 1993. A comparative study of 

fungal endophytes in leaves, xylem and bark of Eucalyptus 

nitens in Australia and England. Sydowia 45, 1–14.

Jacobs R, 2002. Characterisation of Botryosphaeria Species 



from Mango in South Africa. Pretoria, South Africa: 

University of Pretoria, MSc thesis.

Johnson GI, Mead AJ, Cooke AW, Dean JR, 1992. Mango 

stem end rot pathogens – fruit infections by endophytic 

colonisation of the inflorescence and pedicel. Annals of 

Applied Biology 120, 225–34.

Johnson LAS, Briggs BG, 1981. Three old southern 

families – MyrtaceaeProteaceae and Restionaceae

In: Keast A, ed. Ecological Biogeography of Australia

the Hague, the Netherlands: W. Junk, 427–64.

Katoh K, Misawa K, Kuma K, Miyata T, 2002. MAFFT: 

a novel method for rapid multiple sequence alignment 

based on fast Fourier transform. Nucleic Acids Research 



30, 3059–66.

Old KM, Davison EM, 2000. Canker diseases of eucalypts. 

In: Keane PJ, Kile GA, Podger FD, Brown BN, eds. Diseases 

and Pathogens of Eucalypts. Collingwood, Australia: CSIRO 

Publishing, 241–57.

Palgrave KC, 1977. Trees of Southern Africa. Johannesburg, 

South Africa: C. Struik.

Pavlic D, Slippers B, Coutinho TA, Gryzenhout M, Wingfield 

MJ, 2004. Lasiodiplodia gonubiensis sp. nov., a new 



Botryosphaeria anamorph from native Syzygium cordatum in 

South Africa. Studies in Mycology 50, 313–22.

Punithalingam E, 1976. Botryodiplodia theobromae. Kew, UK: 

Commonwealth Mycological Institute: CMI descriptions of 

pathogenic fungi and bacteria no. 519.

Rayner RW, 1970. A Mycological Colour Chart. Kew, UK: CMI 

and British Mycological Society.

Slippers B, 2003. Taxonomy, Phylogeny and Ecology of 



Botryosphaeriaceous Fungi Occurring on Various Woody 

Hosts. Pretoria, South Africa: University of Pretoria, 

PhD thesis.



Plant Pathology (2007) 56, 624–636

636


D. Pavlic et al.

PPA_1608

Slippers B, Crous PW, Denman S, Coutinho TA, Wingfield BD, 

Wingfield MJ, 2004a. Combined multiple gene genealogies 

and phenotypic characters differentiate several species 

previously identified as Botryosphaeria dothidea

Mycologia 96, 83–101.

Slippers B, Fourie G, Crous PW et al., 2004b. Speciation and 

distribution of Botryosphaeria spp. on native and introduced 

Eucalyptus trees in Australia and South Africa. Studies in 

Mycology 50, 343–58.

Slippers B, Fourie G, Crous PW, Coutinho TA, Wingfield BD, 

Wingfield MJ, 2004c. Multiple gene sequences delimit 

Botryosphaeria australis sp. nov. from B. luteaMycologia 

96, 1028–39.

Slippers B, Stenlid J, Wingfield MJ, 2005. Emerging 

pathogens: fungal host jumps following anthropogenic 

introductions. Trends in Ecology and Evolution 20

420–1.

Smith H, Crous PW, Wingfield MJ, Coutinho TA, Wingfield BD, 



2001. Botryosphaeria eucalyptorum sp. nov., a new species in 

the B. dothidea-complex on Eucalyptus in South Africa. 



Mycologia 93, 277–85.

Smith H, Kemp GHJ, Wingfield MJ, 1994. Canker and die-back 

of Eucalyptus in South Africa caused by Botryosphaeria 

dothideaPlant Pathology 43, 1031–4.

Smith H, Wingfield MJ, Crous PW, Coutinho TA, 1996. 



Sphaeropsis sapinea and Botryosphaeria dothidea 

endophytic in Pinus spp. and Eucalyptus spp. in South 

Africa. South African Journal of Botany 62, 86–8.

Swofford DL, 1999. PAUP*. Phylogenetic Analysis Using 



Parsimony (*and Other Methods). Version 4. Sunderland

MA, USA: Sinauer Associates.

White TJ, Bruns T, Lee S, Taylor J, 1990. Amplification and 

direct sequencing of fungal ribosomal RNA genes for 

phylogenetics. In: Innis MA, Gelfand DH, Snisky JJ, White TJ, 

eds. PCR Protocols: a Guide to Methods and Applications. 

San Diego, CA, USA: Academic Press, 315–22.

Wingfield MJ, 2003. Daniel McAlpine Memorial Lecture. 

Increasing threat of disease to exotic plantation forests 

in the southern hemisphere: lessons from cryphonectria 

canker. Australian Plant Pathology 32, 1–7.

Zhou S, Stanosz GR, 2001. Relationships among 



Botryosphaeria species and associated anamorphic fungi 

inferred from the analyses of ITS and 5·8S rDNA sequences. 



Mycologia 93, 516–27.
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