FABI News

FABI Events

FABI in a nutshell

Research Features

Videos

The impact of a tiny beetle and its deadly fungus on South Africa’s forests (Youtube 36 min) by Prof. Wilhelm de Beer, presented at the National Science and Technology Forum (NSTF) for Plant Health in South Africa on 10 June 2021.

Ecological and economic impact of the polyphagous shot hole borer (YouTube, 5 min; 2022) by Stellenbosch University. Click here to view.

International Year of Plant Health: The Polyphagous Shothole Borer’s effect on South Africa's trees (YouTube video 2.18min; 2020) by the University of Pretoria. Click here to view.

FABI Research Features

The potential economic impact of the polyphagous shot hole borer invasion in South Africa

A doctoral study in FABI confirms for the first time the presence of Xylosandrus crassiusculus, a polyphagous ambrosia beetle and its fungal symbiont, Ambroseilla roeperi, in three provinces in South Africa

Non-FABI Publications

Bierman A., F. Roets, J.S. Terblanche (2022) Population structure of the invasive ambrosia beetle, Euwallacea fornicatus, indicates multiple introductions into South Africa. Biological Invasions. 10.1007/s10530-022-02801-x.

de Jager M., F. Roets (2022) Pathogenicity of Fusarium euwallaceae towards apple (Malus domestica) and grapevine (Vitis vinifera). Australasian Plant Disease Notes 17. 10.1007/s13314-022-00456-0.

de Jager M., F. Roets (2022) Rapid and cost-effective detection of Fusarium euwallaceae from woody tissues. Plant Pathology. 10.1111/ppa.13600.

FABI News

Collection of Ambrosia beetle infested material in Durban

14th Online meeting of the Bark Beetle Mycobiome Network

SANBI-funded Sentinel Plant Project establishes a PSHB monitoring system at the KZN National Botanical Garden

PSHB Network meets

University of Pretoria protects trees against PSHB infestation

Scouting for native natural enemies of PSHB

SANBI Sentinel Plant Project hosts a training workshop for DUT horticulture students

The PSHB takes FABI researchers to Somerset West

Polyphagous Shot Hole Borer online resource

Inspection of invasive disease and pest problems in SANBI's Cape gardens

Prof. Wilhelm de Beer receives the SAIF Distinguished Forestry Award

A webinar on Plant Health in Botanical Gardens amid the COVID-19 pandemic

FABIans in the news: Two articles in Wood Southern Africa & Timber Times highlight the work done by the PSHB Research Network

Getting a PSHB research project done before the lockdown

PSHB is spreading in the Western Cape

Monitoring plant health in botanic gardens and arboreta across South Africa

PSHB survey in Northern Cape Pecan orchards

Shothole Borer meetings in the Cape Peninsula

PSHB fungus tested for pathogenicity on commercial forest trees

Shot Hole borer projects launched in forests of the Southern Cape

Shot Hole Borer invasion places FABI in the spotlight

FABI research work features on Carte Blanche

Tree health experts inspect PSHB infestation in Johannesburg suburbs

FABI Team surveys Johannesburg gardens for PSHB infestations

The impact of the Polyphagous Shothole Borer in South Africa explained in a public seminar at FABI

Ambrosia Beetle Working Group formed at FABI 

The PSHB is a 2mm long ambrosia beetle native to Southeast Asia that has a symbiotic relationship with three species of fungi. These include the tree pathogen, Fusarium euwallaceae. This fungus provides a food source for the beetle and its larvae, but in susceptible trees, it kills the vascular tissue, causing branch dieback and tree death. 

In its native environment in Southeast Asia, it seems as if the beetle and fungus do not cause serious damage because tree species have evolved with the beetle-fungus complex and have resistance towards them, and because there are most likely a suite of natural enemies of the beetle. However, the beetle and fungus were somehow introduced into Israel and California in the early 2000s where they caused serious damage on several ornamental trees as well as avocado trees.  In South Africa the impact of the beetle to date is most visible on ornamental trees.

Identification and species name of the beetle

Until December 2018 the PSHB was known as Euwallacea nr. fornicatus. However, Gomez et al. (2018) showed with DNA sequences that 'Euwallacea fornicatus' is actually a species complex including four closely related, but distinct species. These four species of Shot Hole Borer are very similar in shape, and can only be distinguished by specialists under a microscope or with DNA sequences. The four species carry different fungal species, have different host ranges, and different geographical distributions (Gomez et al. 2018). Although they suggested the name Euwallacea whitfordiodendrus should be used for the PSHB, this was an error that was corrected in a subsequent paper by Smith et al. (2019). The correct names of four Shot Hole Borer species in the E. fornicatus complex are:

1. Tea Shot Hole Borer A [TSHB-a = Euwallacea perbrevis (Schedl 1951)]

Distribution: Asia (American Samoa, China, Indonesia, Papua New Guinea, Samoa, Sri Lanka, Taiwan, Thailand), Australia, and introduced in the USA (Florida and Hawaii)

2. Tea Shot Hole Borer B [TSHB-b = Euwallacea fornicatior (Eggers 1923)]

Distribution: Asia (Malaysia, Papua New Guinea, Singapore, Sri Lanka)

3. Polyphagous Shot Hole Borer [PSHB = Euwallacea fornicatus (Eichhoff 1868), previously referred to as Euwallacea nr. fornicatus and Euwallacea whitfordiodendrus (Schedl 1942)] 

Distribution: Asia (China, Hong Kong, Japan, Taiwan, Thailand, and Vietnam) and introduced in USA (California), Israel, South Africa, and Western Australia

4. Kuroshio Shot Hole Borer [KSHB = Euwallacea kuroshio Gomez and Hulcr 2018]

Distribution: Asia (Indonesia, Japan, and Taiwan) and introduced in Mexico and USA (California)

To date, only the PSHB has been found in South Africa. However, both the PSHB and KSHB have invaded California, while TSHB-a has invaded Florida. These species carry similar fungi, have similar life styles and similar effects on trees. With our borders being open for trade to Southeast Asia, the risk that one of the other species can be introduced is very high. Co-occurring species increase the chances for interbreeding which will enhance the adaptability of the beetles to new hosts and new environments, posing a greater threat. From a management perspective, they are dealt with in the same ways. In California they have thus started referring to the PSHB and KSHB jointly with the single term Invasive Shot Hole Borers (ISHB). It is recommended that for management and legislative purposes we also adopt the term ISHB in South Africa.

The Polyphagous Shot Hole Borer is an ambrosia beetle native to Southeast Asia. The beetle has a symbiotic relationship with the fungus Fusarium euwallaceae, which causes branch die-back and can kill susceptible trees. In 2017 the presence of this pest was confirmed in South Africa by the FABI team, and it has since been found in all provinces except Limpopo. This makes the PSHB invasion in South Africa the largest geographical outbreak of this beetle in the world. It is affecting trees in all sectors: the agricultural and commercial forestry sector, urban trees (public spaces, streets, gardens), as well as native trees in natural forests.

At present researchers at FABI, in collaboration with colleagues from several other Universities, are coordinating monitoring efforts and leading research on the PSHB and its fungus in South Africa. The purpose of this webpage is to provide:

1. Background information on the PSHB and its management to the general public and all stake holders,
2. Updated information on its distribution and its host trees in South Africa,
3. Feedback on ongoing research and monitoring efforts by the PSHB Research Network, and
4. A platform for the public to make us aware of possible new host trees of PSHB and localities where it occurs.

 

 


 

New Publications

Fick A, Swart V, Van den Berg N. (2025) In silico prediction method for plant Nucleotide-binding leucine-rich repeat- and pathogen effector interactions. The Plant Journal 122:e70169. 10.1111/tpj.70169
Bose T, Wingfield MJ, Brachmann A, Witfeld F, Begerow D, Kemler M, Dovey S, Roux J, Slippers B, Vivas M, Hammerbacher A. (2025) Removal of organic biomass in Eucalyptus plantations has a greater impact on fungal than on bacterial networks. Forest Ecology and Management 586:122734. 10.1016/j.foreco.2025.122734
Woodward S, Amin H, Mártin-Gárcia J, Solla A, Diaz-Vazquez R, Romeralo C, Alves A, Pinto G, Herron D, Fraser S, Zas R, Doğmuş-Lehtijärvi HT, Bonello P, Wingfield MJ, Witzell J, Diez JJ. (2025) Host-pathogen interactions in the Pine-Fusarium circinatum pathosystem and the potential for resistance deployment in the field. Forest Pathology 55(2):e70020. 10.1111/efp.70020
Maduke N, Slippers B, Van der Linde E, Wingfield M, Fourie G. (2025) Botryosphaeriaceae associated with racemes, fruits and leaves of macadamia in South Africa. Plant Pathology 0:1–15:1–15. 10.1111/ppa.14107
Hulcr J, Barnes I, Barnes M, Gazis R, Hammerbacher A, Johnson AJ, Lynch S, Lynn K, Marais GC, Mayers CG, Nel W, Villari C, Wingfield BD, Wingfield MJ. (2025) From forest to fungus: A roadmap to bark beetle mycobiome research. Phytoparasitica 53(45) 10.1007/s12600-025-01246-x
Knoppersen RS, Bose T, Coutinho TA, Hammerbacher A. (2025) Inside the Belly of the Beast: Exploring the Gut Bacterial Diversity of Gonipterus sp. n. 2. Microbial Ecology 88:27. 10.1007/s00248-025-02524-1
Bose T, Roux J, Titshall L, Dovey SB, Hammerbacher A. (2025) Mulching of post-harvest residues and delayed planting improves fungal biodiversity in South African Eucalyptus plantations and enhances plantation productivity. Applied Soil Ecology 210:106091. 10.1016/j.apsoil.2025.106091
Wychkuys KA, Giron E, Hyman G, Barona E, Castro-Llanos FA, Sheil D, Yu L, Du Z, Hurley BP, Slippers B, Germishuizen I, Bojacá CR, Rubiano M, Sathyapala S, Verchot L, Zhang W. (2025) Biological control protects carbon sequestration capacity of plantation forests. Entomologia Generalis 10.1127/entomologia/2025/3015 PDF
Balocchi F. (2025) Risk Analysis for Alien Taxa (RAAT) for Phytophthora cinnamomi in South Africa. 10.5281/zenodo.14858265
Paap T, Balocchi F, Wingfield MJ. (2025) The root rot pathogen Phytophthora cinnamomi: a long-overlooked threat to the Cape Floristic Region of South Africa. Biological Invasions 27(4) 10.1007/s10530-025-03570-z PDF
Harikrishnan K, Rajeshkumar KC, Patil PM, Jeewon R, Visagie CM. (2025) Aspergillus dhakephalkarii and A. patriciawiltshireae spp. nov., two new species in Aspergillus sect. Nigri ser. Japonici (Eurotiales, Aspergillaceae) from India. Phytotaxa 695:57–79. 10.11646/phytotaxa.695.1.2
Dewing C, Visagie CM, Steenkamp ET, Wingfield BD, Yilmaz N. (2025) Three new species of Fusarium (Nectriaceae, Hypocreales) isolated from Eastern Cape dairy pastures in South Africa. MycoKeys 115:241–271. 10.3897/mycokeys.115.148914 PDF
Coertze S, Visagie CM, Rose L, Slippers B, Mostert D, Makhura T, de Villiers D, Basson E, Coetzee B, Read D. (2025) First report of Clavibacter nebraskensis, causing Goss’s bacterial leaf blight on maize (Zea mays L.) in South Africa. Plant Disease 10.1094/PDIS-01-25-0164-PDN PDF
van der Merwe E, Slippers B, Dittrich-Schröder G. (2025) Exploring artificial diets for the laboratory rearing of Sirex noctilio late-instar larvae: a qualitative study. Zenodo 10.5281/zenodo.15049303
Mapfumo P, Archer E, Swanevelder ZH, Wilken M, Creux N, Read DA. (2025) Plant Pathology. Genomic Characterisation of Bidens mottle virus in South Africa and an Assessment of the Impact on Helianthus annuus (Sunflower) in an Open Field Setting 10.1111/ppa.14089
Brasier CM, Grünwald NJ, Bourret TB, Govers F, Scanu B, Cooke DEL, Bose T, Hawksworth DL, Abad ZG, Albarracin MV, Alsultan W, Altamirano-Junqueria AE, Arifin AR, Arnet MJ, Aumentado HDR, Bakonyi J, Belisle WH, Benigno A, Bienapfl JC, Bilodeau GJ, Blair JE, Botella L, Brandano A, Cacciola SO, Carbone I, Castroagudin VL, Chaendaekattu N, Consford JD, Corcobado T, Covey PA, Daniels HA, Deidda A, Dorrance AE, Dort EN, Drenth A, Drizou F, Evangelisti E, Fajardo SN, Fang Y, Ference CM, Frankel SJ, Goss EM, Guest DI, Hardy GESJ, Harris ARH, Hawku MD, Heungens K, Hong C, Horner IJ, Horta Jung M, Iyanda OJ, Jamieson B, Jeffers SN, Judelson HS, Junaid M, Kalogeropoulou E, Kamoun S, Kang S, Kasuga T, Kudláček T, LeBoldus J, Lee CA, Li D, Llanos AK, Lopez-Nicora HD, Machado H, Di San Lio GM, Maia C, Mandal K, Manosalva P, Martin FN, Matson MEH, McDougal RL, McDowell JM, Michelmore RW, Milenković I, Moricca S, Mostowfizadeh-Ghalamfarsa R, Nagy Z, Nikolaeva EV, Ortega-López P, Paap T, Parada-Rojas CH, Peduto Hand F, Perez-Sierra A, Pettersson M, Prasad P, Puig AS, Raco M, Rajput NA, Ristaino JB, Rooney-Latham S, Seidl MF, Shamoun SF, Solla A, Spies CFJ, Sudermann MA, Swiecki TJ, Tian M, Tripathy S, Uematsu S, Van Poucke K, Vichou AE, Walter M, Webber JF, Williams NM, Wingfield MJ, Yadav D, Yang X, Jung T. (2025) Preserving the Biologically Coherent Generic Concept of Phytophthora, ‘Plant Destroyer’. Phytopathology 10.1094/PHYTO-11-24-0372-LE
Stazione L, Corley JC, Allison JD, Hurley BP, Lawson SA, Lantschner MV. (2025) Novel associations among insect herbivores and trees: Patterns of occurrence and damage on pines and eucalypts. Ecological Applications 35:e70018. 10.1002/eap.70018
Townsend G, Hill M, Hurley BP, Roets F. (2025) Escalating threat: increasing impact of the polyphagous shot hole borer beetle, Euwallacea fornicatus, in nearly all major South African forest types. Biological Invasions 27 10.1007/s10530-025-03551-2 PDF
Makunde PT, Slippers B, Bush S, Hurley BP. (2025) Host specificity and host stage preference of Psyllaephagus species (Hymenoptera: Encyrtidae) towards invasive eucalypt psyllids (Hemiptera: Aphalaridae). Agricultural and Forest Entomology :1-13. 10.1111/afe.12679
Tarigan M, Wingfield MJ, Jami F, Oliveira LSS, Saha MA, Durán A, Pham NQ. (2025) Pathogenicity of Pythium myriotylum on Acacia crassicarpa and Acacia mangium × Acacia auriculiformis clones in Indonesia. Southern Forests: a Journal of Forest Science 87:1–5. 10.2989/20702620.2024.2432863
D’Angelo D, Hu H, Lahoz E, Risteski J, Steenkamp E T, Viscardi M, van der Nest M A, Wu Y, Yu H, Zhou J, Karandeni Dewage C S, Kotta-Loizou L I, Stotz H U, Fitt B D L, Huang Y, Hu Y, Kiss L, Sorrentino R, Nkomo T, Zhou X, Vaghefi N, Sonnekus B, Bose T, Cerrato D, Cozzolino L, Creux N, D’Agostino N, Fourie G, Fusco G, Hammerbacher A, Idnurm A, Wingfield BD. (2025) IMA GENOME - F20 A draft genome assembly of Agroathelia rolfsii, Ceratobasidium papillatum, Pyrenopeziza brassicae, Neopestalotiopsis macadamiae, Sphaerellopsis filum and genomic resources for Colletotrichum spaethianum and Colletotrichum fructicola. IMA Fungus 16:e141732. 10.3897/imafungus.16.141732
Espach A, Esterhuizen L, Africander N, Thiart S, Read DA, Pietersen G. (2025) First report of pepper ringspot virus on potato (Solanum tuberosum) in South Africa. Journal of Plant Pathology 10.1007/s42161-025-01887-1
Muema EK, van Lill M, Venter SN, Claassens R, Steenkamp ET. (2025) Mesorhizobium salmacidum sp. nov. and Mesorhizobium argentiipisi sp. nov. are symbionts of the dry-land forage legumes Lessertia diffusa and Calobota sericea. Antonie van Leeuwenhoek 19(3):1-20. 10.1007/s10482-025-02063-2
Motaung TE, Ratsoma FM, Kunene S, Santana QC, Steenkamp ET, Wingfield BD. (2025) Harnessing exogenous membrane vesicles for studying Fusarium circinatum and its biofilm communities. Microbial Pathogenesis 10.1016/j.micpath.2025.107368
van Dijk A, Wilson AM, Marx B, Hough B, Swalarsk-Parry BS, De Vos L, Wingfield MJ, Wingfield BD, Steenkamp ET. (2025) CRISPR-Cas9 genome editing reveals that the Pgs gene of Fusarium circinatum is involved in pathogenicity, growth and sporulation.. Fungal Genetics and Biology 10.1016/j.fgb.2025.103970
Balocchi F, Wingfield MJ, Paap T. (2025) First record of the white root rot fungus Dematophora necatrix on indigenous South African trees. Journal of Plant Pathology 10.1007/s42161-025-01861-x PDF
Coelho MA, David-Palma M, Aylward J, Pham NQ, Visagie CM, Fuchs T, Yilmaz N, Roets F, Sun S, Taylor JT, Wingfield BD, Fisher MC, Wingfield MJ, Heitman J. (2025) Decoding Cryptococcus: From African biodiversity to worldwide prevalence. PLOS Pathogens 21:e1012876. 10.1371/journal.ppat.1012876
Solís M, Hammerbacher A, Wingfield M.J, Naidoo S. (2025) Enhancing plantation forest sustainability: A review of Eucalyptus defence mechanisms to foliar fungal pathogens. Current Forestry Reports 10.1007/s40725-024-00243-3
Ratsoma MF, Santana QC, Wingfield BD, Steenkamp ET, Motaung TE. (2025) Understanding cargo sorting and interactive effects of membrane vesicles in fungal phytopathogens: Current knowledge and research gaps. Fungal Biology Reviews 51 10.1016/j.fbr.2025.100411
Harvey A, van den Berg N, Swart V. (2025) In silico characterisation of the avocado WAK/WAKL gene family with a focus on genes involved in defence against Phytophthora cinnamomi. Frontiers in Plant Science 15:1474781. 10.3389/fpls.2024.1474781 PDF
Botes J, Ma X, Chang J, Van de Peer Y, Berger DK. (2025) Flavonoids and anthocyanins in seagrasses: implications for climate change adaptation and resilience. Frontiers in Plant Science 15(1520474):1-17. 10.3389/fpls.2024.1520474
Wondafrash M, Wingfield MJ, Hurley BP, Slippers B, Mutitu EK, Jenya H, Paap T. (2025) DNA sequence data confirms the presence of two closely related cypress-feeding aphid species on African cypress (Widdringtonia spp.) in South Africa. Southern Forests 86:278-285. 10.2989/20702620.2024.2390863 PDF
Mangani R, Mazarura J, Matlou S, Marquart A, Archer E, Creux N. (2025) The impact of past and current district-level climatic shifts on maize production and the implications for South African farmers. Theoretical and Applied Climatology 156:109. 10.1007/s00704-024-05334-6
Möller H, Slippers B, van den Berg N. (2025) Branch canker battles: understanding and managing the Botryosphaeriaceae in avocado. Phytoparasitica 53(17) 10.1007/s12600-024-01227-6
Pham NQ, Wingfield BD, Barnes I, Gazis R, Wingfield MJ. (2025) Elsinoe species: The rise of scab diseases. Plant Pathology 10.1111/ppa.14015
Theron E, van Niekerk JM, van der Waals JE. (2025) A review of the use of phosphonates in the management of Phytophthora nicotianae in citrus in South Africa. Phytoparasitica 53(11) 10.1007/s12600-024-01234-7 PDF
Aylward J, Atkins S, Roets F, Wingfield BD, Wingfield MJ. (2025) Several Seiridium species (Sporocadaceae: Xylariales) cause cypress canker in South Africa. Fungal Biology 129:101528. 10.1016/j.funbio.2024.101528
Martin G, Canavan K, Chikowore G, Bugan R, De Lange W, du Toit B, Harding G, Heath R, Hill M, Hurley BP, Ivey P, Muir D, Musedeli J, Richardson DM, Slippers B, Stafford L, Turner A, Watson K, van Wilgen BW. (2025) Managing wilding pines in the Cape Floristic Region, South Africa: Progress and prospects. South African Journal of Botany 177:377-391. 10.1016/j.sajb.2024.12.011 PDF
Wingfield MJ, Slippers B, Barnes I, Duong AT, Wingfield BD. (2025) The Pine pathogen Diplodia sapinea: Expanding frontiers. Current Forestry Reports 11(2) 10.1007/s40725-024-00236-2
Hurley BP, Lawson S, Slippers B. 2025. Biological Control of Insect Pests in Plantation Forests. Springer: Switzerland.
Mangani R, Archer E, Engelbrecht C, Bellochi G, Mukiibi A, Creux N. 2025. The Impact of Climate Change on Crop Production and Food Security: A South African Perspective. In: Climate Change, Food Security, and Land Management. Leal Filho W, Matandirotya N, Yayeh Ayal D, Luetz JM, Borsari B. (eds). Springer, Cham, Switzerland, pp 1-12.
Goundar P, Slippers B, Hurley BP, Lawson SA. 2025. Classical biological control of bark and wood borers in Pinus plantations. In: Biological Control of Insect Pests in Plantation Forests. Hurley BP, Lawson SA, Slippers B. (eds). Springer, Cham, Switzerland, pp 321-338.
Hurley BP, Slippers B, Lawson SA. 2025. Biological control in plantation forests: trends and opportunities. In: Biological Control of Insect Pests in Plantation Forests. Hurley BP, Lawson SA, Slippers B. (eds). Springer, Cham, Switzerland, pp 3-18.
Slippers B, Fitza KNE, Garnas JR. 2025. Genetic diversity should be considered in biological control programmes in plantation forestry. In: Biological Control of Insect Pests in Plantation Forests. Hurley BP, Lawson SA, Slippers B. (eds). Springer, Cham, Switzerland, pp 71-94.
Wondafrash M, Slippers B, Hurley BP. 2025. Accidental introductions of natural enemies in plantation forests. In: Biological Control of Insect Pests in Plantation Forests. Hurley BP, Lawson SA, Slippers B. (eds). Springer, Cham, Switzerland, pp 161-190.
Ashmore JS, Slippers B, Duong TA, Dittrich-Schröder G. (2024) Understanding the genetics of sex determination in insects and its relevance to genetic pest management. Insect Molecular Biology 10.1111/imb.12982
Oostlander AG, Elfstrand M, Oliva J, Stenlid J, Well L, Grober C, Klawonn F, Brandt U, Becker Y, Slippers B, von Bargen M, Brodde L, Fleißner A. (2024) Development of a molecular genetics and cell biology toolbox for the filamentous fungus Diplodia sapinea. PLoS ONE 19:e0308794. 10.1371/journal.pone.0308794
Balocchi F, Sanfuentes E. (2024) Fungal pathogens on Scotch broom (Cytisus scoparius) and French broom (Genista monspessulana) from Chile. Forest Pathology 54 10.1111/efp.70004
Knoppersen R, Hammerbacher A, Bose T. (2024) Fungal Planet description sheets: 1697–1780 (Description of Sporisorium enterogonipteri). Fungal Systematics and Evolution 14:325–577. 10.3114/fuse.2024.14.19
Wingfield BD, Wingfield MJ. (2024) Gene transfer between fungal species triggers repeated coffee wilt disease outbreaks. PLOS Biology 10.1371/journal.pbio.3002901