Research Articles (Forestry and Agricultural Biotechnology Institute (FABI))

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Plant pathogen name game : Cross Kingdom Review for the naming of biotic agents associated with plants
(Annual Reviews, 2025-09) Bull, Carolee T.; Salgado-Salazar, Catalina; Romberg, Megan K.; Allen, Cavan; Kantor, Mihail; Handoo, Zafar; Aboughanem-Sabanadzovic, Nina; Sabanadzovic, Sead; Coutinho, Teresa A.
To communicate across scientific disciplines, regulatory bodies, and the agricultural community, the naming of plant pathogens assigned to specific taxa is critical. Here, we provide an overview of the nomenclatural systems governing the naming of plant-pathogenic nematodes, fungi, oomycetes, prokaryotes, and viruses. Although we focus on the nature of the nomenclatural codes, we briefly discuss fundamental principles of taxonomy, including classification and identification. Key elements of the codes of nomenclature that ensure stability and clarity when naming species of pathogens are defined. When comparing the practice of nomenclature across different kingdoms, the classification and nomenclatural systems differ, and thus unique challenges are faced. We provide guidance from the codes and current practice for naming novel species. When there are nomenclatural conflicts, international committees play a critical role in their resolution. They also play a role in updating the codes to reflect new advancements in science. With this review, we aim to assist plant pathologists, journal editors, and those in related fields by providing an entrée to the legalistic requirements of the codes. Authors must consult and follow the rules of the appropriate code for any proposal of new or new combinations of names. To those interested in naming new species (or renaming the current ones), we recommend collaborations with experts in the field of taxonomy to ensure that rules for accurate and consistent naming practices and procedures are followed and to increase the likelihood that the proposed nomenclature is correct and acceptable.
Cryphonectriaceae : biodiverse and threatening tree pathogens in the tropics and southern hemisphere
(Annual Reviews, 2025-09) Wingfield, Michael J.; Pham, Nam Q.; Marincowitz, Seonju; Wingfield, Brenda D.; mike.wingfield@fabi.up.ac.za
The chestnut blight pathogen Cryphonectria parasitica is well-known for the devastation it caused to North American forests. It is less well recognized that numerous other fungi in the Cryphonectriaceae are emerging as threats to native and planted forests in the tropics and Southern Hemisphere. Unlike C. parasitica, these fungi, such as Chrysoporthe cubensis, initially gained attention due to a canker disease in plantations of non-native Eucalyptus. More than four decades of research have revealed a wide diversity of Cryphonectriaceae species that infect many other tree genera in the Myrtales. These fungi often exist as endophytes but become problematic when trees are planted outside their native range. Growing numbers of species are also undergoing host shifts from native to susceptible trees such as Eucalyptus, posing serious risks to both natural and planted forests. These fungi provide an example of the biodiversity of tree-infecting fungi that is understudied, despite their significant potential to harm forest ecosystems.
Investigating bark, ambrosia and nitidulid beetle (Coleoptera : Scolytinae and Nitidulidae) communities and their potential role in the movement of Ceratocystis manginecans in commercial forestry plantations in Riau, Indonesia
(Wiley, 2025-11) Lynn, Kira Mary Theresa; Wingfield, Michael J.; Tarigan, Marthin; Duran, Alvaro; Santos, Samuel A.; Nel, Wilma Janine; Barnes, Irene; irene.barnes@fabi.up.ac.za
Ceratocystis Canker and Wilt Disease (CCWD), caused by the fungal pathogen Ceratocystis manginecans, poses a significant threat to Acacia and Eucalyptus plantations in Indonesia. Infections typically occur through wounds on the main stems of trees, and infected trees, particularly Acacia, are often co-infested by various wood-associated beetles. The aim of this study was to identify the beetle species associated with Ceratocystis-infected trees and to assess their potential role in dispersing C. manginecans. Beetle and frass samples were collected from Ceratocystis-infected compartments of Acacia and Eucalyptus propagated as monocultures in Riau, Indonesia, either by using traps or by direct collection from infected trees. The samples were screened for the presence and viability of Ceratocystis propagules using a quantitative polymerase chain reaction-high-resolution melting analysis (qPCR-HRMA) diagnostic tool and a carrot baiting technique, respectively. Fourteen beetle species, predominantly collected from traps, representing nine genera of the Scolytinae and Nitidulidae, were identified from the two plantation types. The qPCR tool detected the presence of Ceratocystis DNA on 13 of the 14 beetle species at concentrations as low as 0.015–0.0019 ng. However, viable Ceratocystis propagules could not be recovered from these beetles using culture-based methods. Of the 105 frass samples screened, qPCR detected Ceratocystis DNA in 67 samples; however, only one Ceratocystis isolate was obtained using the carrot baiting method. The results of this study suggest that the beetles and beetle frass can harbour Ceratocystis propagules, as indicated by the detection of fungal DNA. However, the viability of the propagules and the ability of the beetles and/or beetle frass to spread C. manginecans requires further investigation.
Early detection of Phytophthora root rot in Eucalyptus using hyperspectral reflectance and machine learning
(Elsevier, 2025-10) Esterhuizen, Hendrik J.; Slippers, Bernard; Bosman, Anna Sergeevna; Roux, Jolanda; Jones, Wayne; Bose, Tanay; Hammerbacher, Almuth; tanay.bose@fabi.up.ac.za
The rising prevalence of Phytophthora diseases in forests highlights the need for rapid, non-invasive detection methods. Early-stage root infections are difficult to detect due to the absence of visible above-ground symptoms, while current diagnostics remain slow and invasive. This study investigated whether hyperspectral leaf reflectance could detect root rot caused by Phytophthora alticola in Eucalyptus benthamii. Nineteen commercially planted families were inoculated, and leaf spectra were collected using an ASD FieldSpec 4 sensor. A machine learning pipeline was developed to identify diagnostic spectral signals. Key wavelengths were identified using permutation importance, a genetic algorithm, and self-attention network (SAN) scores. Spectral signals linked to root rot revealed that infection was correlated with leaf pigment accumulation and moisture stress. Three algorithms, random forest (RF), support vector machine (SVM), and SAN, were trained on hyperspectral data to predict P. alticola infection. The SAN achieved 97 % accuracy on a reduced dataset, which included the diagnostic wavelengths from the feature selection step, surpassing the RF (96 %) and SVM (94 %) models. This study demonstrates hyperspectral sensing as an effective tool for detecting Phytophthora root rot using spectra from the foliage and highlights the application of advanced machine learning techniques for plant disease classification. HIGHLIGHTS • Hyperspectral sensing detects Phytophthora root rot before symptoms appear. • SAN model achieved 97 % accuracy using selected wavelengths from leaf spectra. • Key wavelengths correlated with pigment shifts and moisture stress in leaves. • Machine learning identified spectral markers for early disease detection. • Vegetation indices NDNI and MSI are strongly linked to infection status.
Chemodiversity of penicillium isolated from alpine and arctic environments, including ten new species
(Westerdijk Fungal Biodiversity Institute, 2025-08-01) Overy, D.P.; Frisvad, J.C.; Witte, T.E.; Hicks, C.L.; Hermans, A.; Sproule, A.; Louis-Seize, G.; Seifer, K.A.; Yilmaz, Neriman; Price, Jodi; Van Vuuren, Nicole Innike; Visagie, Cobus M.; cobus.visagie@fabi.up.ac.za
Polar, high altitude montane and cold desert environments harbour only sparse plant life and often remain frozen for extended periods. Because of their remoteness, often combined with restricted access, such regions are rarely visited and the fungal biodiversity of the soils is scarcely studied. Despite this, when such studies are undertaken, psychrophilic Penicillium species are often reported and the isolates exhibit a high spectrum of biologically active compounds of biotechnological interest. Small molecule profiling by mass spectrometry (often called ‘metabolomics’) can supplement phylogenetic species concepts and provide information to characterize variation within species or populations. During large scale fungal isolation surveys exploring new psychrophilic fungi from high altitude alpine and arctic tundra soils, several undescribed Penicillium species were discovered. A polyphasic taxonomic approach was adopted to formally describe ten new species using multigene phylogenetic analyses and phenotypic characterizations including secondary metabolite production, colony characters, and microscopic analysis of morphological structures. Using untargeted metabolomics and molecular networking tools, an emphasis was made to characterize, compare and discuss in depth, the chemical diversity associated with these new Penicillium species.
Factors that influence the flight activity, abundance and infestation severity of the polyphagous shot hole borer beetle (PSHB, Euwallacea fornicatus) in an urban-agricultural fringe setting
(Elsevier, 2025-10) Roberts, Elise; Paap, Trudy; Roets, Francois
The polyphagous shot hole borer (PSHB, Euwallacea fornicatus) has invaded multiple countries, including South Africa. Along with its fungal mutualist, PSHB has caused the death of a wide range of tree species. Unmitigated costs of invasion in South Africa are estimated to be high. This study consisted of a 26-month PSHB monitoring programme using baited traps in an urban-agricultural fringe setting in the Western Cape province, focusing on revealing the factors most important to flight activity, beetle abundance, and infestation severity. It also tested the validity of felling infested trees as a management option to reduce beetle numbers (propagule pressure). More than half of the 94 study plots evaluated had PSHB-infested trees. Beetle flight activity was highest in summer and negligible in winter, with flight activity being positively correlated with temperature, beetle developmental degree days and beetle flight hours. The surrounding abundance of infested hosts was positively correlated with beetle abundance and infestation levels, though “saturation” in the infestation of a focal host tree may be a deterrent to dispersing beetles. Trees in plots that experience water stress (seasonal flooding) had higher dispersing beetle abundance and infestation levels, suggesting that tree stress might play a role in attracting beetles or making trees more vulnerable to infestation. Beetle activity during tree felling echoed the overall seasonal trend, and higher numbers of dispersing beetles on the day of tree felling in summer suggest that felling activities should best be conducted in winter. For three host tree species, infestation severity increased with decreasing tree size, which may be due to larger trees having thicker bark or other better defence systems. This study provides insight into the ecology of PSHB in this region of South Africa, which is important for developing monitoring and management strategies.
Minimal information for studies of extracellular vesicles (MISEV2023) : fom basic to advanced approaches
(Elsevier, 2024-02) Welsh, Joshua A.; Goberdhan, Deborah C.I.; O’Driscoll, Lorraine; Buzas, Edit I.; Blenkiron, Cherie; Bussolati, Benedetta; Cai, Houjian; Di Vizio, Dolores; Driedonks, Tom A.P.; Erdbrügger, Uta; Falcon-Perez, Juan M.; Fu, Qing-Ling; Hill, Andrew F.; Lenassi, Metka; Lim, Sai Kiang; Mahoney, My G.; Mohanty, Sujata; Möller, Andreas; Nieuwland, Rienk; Ochiya, Takahiro; Sahoo, Susmita; Torrecilhas, Ana C.; Zheng, Lei; Zijlstra, Andries; Abuelreich, Sarah; Bagabas, Reem; Bergese, Paolo; Bridges, Esther M.; Brucale, Marco; Burger, Dylan; Carney, Randy P.; Cocucci, Emanuele; Colombo, Federico; Crescitelli, Rossella; Hanser, Edveena; Harris, Adrian L.; Haughey, Norman J.; Hendrix, An; Ivanov, Alexander R.; Jovanovic-Talisman, Tijana; Kruh-Garcia, Nicole A.; Faustino, Vroniqa Ku’ulei-Lyn; Kyburz, Diego; Lässer, Cecilia; Lennon, Kathleen M.; Lötvall, Jan; Maddox, Adam L.; Martens-Uzunova, Elena S.; Mizenko, Rachel R.; Newman, Lauren A.; Ridolfi, Andrea; Rohde, Eva; Rojalin, Tatu; Rowland, Andrew; Saftics, Andras; Sandau, Ursula S.; Saugstad, Julie A.; Shekari, Faezeh; Swift, Simon; Ter-Ovanesyan, Dmitry; Tosar, Juan P.; Useckaite, Zivile; Valle, Francesco; Varga, Zoltan; Van der Pol, Edwin; Van Herwijnen, Martijn J.C.; Wehman, Ann M.; Williams, Sarah; Zendrini, Andrea; Zimmerman, Alan J.; MISEV Consortium Clotilde Théry; Witwer, Kenneth W.; Abuelreich, Sarah; Ahmad, Samar; Ahmed, Dina Ak.; Ahmed, Sarah H.; Aikawa, Elena; Akbar, Naveed; Akiyoshi, Kazunari; Al-Adra, David P.; Al-Masawa, Maimonah E; Albanese, Manuel; Alberro, Ainhoa; Alcaraz, María José; Alexander-Brett, Jen; Alexander, Kimberley L.; Ali, Nilufar; Alibhai, Faisal J.; Allelein, Susann; Allenby, Mark C.; Almeida, Fausto; Almousa, Sameh W.; Altan-Bonnet, Nihal; Altei, Wanessa F.; Alvarez-Llamas, Gloria; Alvarez, Cora L.; An, Hyo Jung; Anand, Krishnan; Anderson, Johnathon D.; Andriantsitohaina, Ramaroson; Ansari, Khairul I.; Anselmo, Achille; Antoniou, Anna; Aqil, Farrukh; Arab, Tanina; Archer, Fabienne; Arif, Syrine; Armstrong, David A.; Arntz, Onno J.; Arsène, Pierre; Arteaga-Blanco, Luis; Asokan, Nandini; Aspelin, Trude; Atkin-Smith, Georgia K.; Aubert, Dimitri; Ayyar, Kanchana K.; Azlan, Maryam; Azoidis, Ioannis; Bécot, Anaïs; Bach, Jean-Marie; Bachurski, Daniel; Bae, Seoyoon; Bagabas, Reem; Baj-Krzyworzeka, Monika; Balaj, Leonora; Van Balkom, Bas Wm .; ABallal, bhijna R.; Bano, Afsareen; Banzet, Sébastien; Bare, Yonis; Barile, Lucio; Barman, Bahnisikha; Barranco, Isabel; Barreca, Valeria; Bart, Geneviève; Barteneva, Natasha S.; Basso, Manuela; Batish, Mona; Bauer, Natalie R.; Baxter, Amy A.; Bazié, Wilfried W.; Bazzan, Erica; Beaumont, Joel Ej.; Bebawy, Mary; Bebelman, Maarten P.; Bedina-Zavec, Apolonija; Beetler, Danielle J.; Beke-Somfai, Tamás; Belleannée, Clémence; Benedikter, Birke J.; Benediktsdóttir, Berglind E.; Berardi, Anna C.; Bergamelli, Mathilde; Bergese, Paolo; Bertolini, Irene; Bhattacharyya, Asima; Bhattacharyya, Suvendra N.; Biller, Steven J.; Billottet, Clotilde; Bissler, John J.; Blanc-Brude, Olivier; Blenkiron, Cherie; Blijdorp, Charles J.; Bobis-Wozowicz, Sylwia; Bodart-Santos, Victor; Bodnár, Bernadett R.; Boilard, Eric; Boireau, Wilfrid; Bokun, Vladimir; Bollard, Stephanie M.; Bollini, Sveva; Bongiovanni, Antonella; Bongiovanni, Laura; Bonifay, Amandine; Boppart, Marni D.; Borràs, Francesc E.; Bosch, Steffi; Boselli, Daniela; Bottini, Massimo; Bouffard, Jeff; Boulanger, Chantal M.; Boutros, Paul C.; Boyadjian, Oscar; Boysen, Anders T.; Bozkurt, Batuhan T.; Bramich, Kyle P.; Braun, Fabian; Bravo-Miana, Rocío Del Carmen; Breakefield, Xandra O.; Brenna, Santra; Brennan, Kieran; Brennan, Meadhbh Á.; Breyne, Koen; Bridges, Esther M.; Brigstock, David R.; Brisson, Alain R.; Brodie, Chaya; Brucale, Marco; Bruno, Katelyn A.; Bucci, Cecilia; Buch, Shilpa; Buck, Amy H.; Bukva, Mátyás; Bulte, Jeff Wm.; Buratta, Sandra; Burger, Dylan; Burgy, Olivier; Burnier, Julia V.; Burrows, Kaiping; Busatto, Sara; Bussolati, Benedetta; Buzas, Edit I.; Buzas, Krisztina; Byrd, J. Brian; Cáceres-Verschae, Albano; Cai, Houjian; Caires, Hugo R.; Campos-Silva, Carmen; Camussi, Giovanni; de Candia, Paola; Carceller, Carmen; Fernandez-Becerra, Carmen; Carney, Randy P.; Carrasco, Alexis G. Murillo; Carter, David Rf.; Cavallaro, Sara; Cavallero, Serena; Cavallero, Sophie; Cerda-Troncoso, Cristóbal; Chahwan, Richard; Chalupská, Renata; Chamley, Lawrence W.; Chandra, Partha K.; Chang, Wen-Wei; Charest, A.l.; Chen, Chihchen; Chen, Hao; Chen, Qiang; Chen, Shuai; Chen; Chen, Yunxi; Cheng, Lesley; Chernyshev, Vasiliy S.; Chetty, Venkatesh Kumar; Chitti, Sai V.; Cho, Ssang-Goo; Cho, Yoon-Kyoung; Choi, Byeong Hyeon; Chutipongtanate, Somchai; Cicardi, Maria Elena; Cifuentes-Rius, Anna; Ciullo, Alessandra; Clayton, Aled; Cleary, Jacob A.; Cocozza, Federico; Cocucci, Emanuele; Coffey, Robert J.; Collino, Federica; Colombo, Federico; Colosetti, Pascal; Compañ-Bertomeu, Alvaro; Constanzo, Julie; Corbeil, Denis; Cordeiro-da-Silva, Anabela; Costa, Júlia; Couch, Yvonne; Courageux, Yvan; Coutant, Kelly; Coyle, Beth; Crescitelli, Rossella; Cretich, Marina; Cronemberger-Andrade, André; Crossland, Rachel E.; Cucher, Marcela A.; Czystowska-Kuzmicz, Malgorzata; D'Acunzo, Pasquale; D'Agnano, Igea; D'Agostino, Vito G.; D'Angelo, Gisela; D'Arrigo, Daniele; D'Souza-Schorey, Crislyn; Dagur, Raghubendra S.; Danielson, Kirsty M.; Das, Saumya; Dauphin, Thibaud; Davidson, Sean M.; Davies, Owen G.; Davis, Chelsea N.; Deep, Gagan; Degosserie, Jonathan; Van Delen, Mats; Deliwala, Vatsal; Dellar, Elizabeth R.; Van Deun, Jan; Dev, Apurba; Deville, Sarah; Devitt, Andrew; Dhondt, Bert; Dieterich, Lothar C.; Dittmer, Dirk P.; Dobosh, Brian; Dobra, Gabriella; Dogra, Navneet; Dohi, Eisuke; Dolo, Vincenza; Domashevich, Timothy V.; Dominici, Massimo; Dong, Liang; Doré, Etienne; Dragovic, Rebecca A.; Driedonks, Tom Ap.; Drittanti, Lila; Droste, Marvin; Duan, Wei; Durmaz, Esmahan; Dutta, Suman; Eguchi, Takanori; Eichenberger, Ramon M.; Eitan, Erez; Ekström, Karin; El Andaloussi, Samir; Eldh, Maria; Elie-Caille, Celine; Enciso-Martinez, Agustin; Erdbrügger, Uta; Esmaeili, Rezvan; Ettelaie, Camille; Försönits, András I.; Fabbri, Muller; Falasca, Marco; Falcon-Perez, Juan M.; Fan, Hongkuan; Fatima, Farah; Faustino, Vroniqa Ku'ulei-Lyn; Fazeli, Alireza; Fernández-Rhodes, María; Fernandez-Prada, Christopher; Ferraro, Mariola J.; Ferreira, Joao N.; Ferreira, Rafaela F.; Figueroa-Hall, Leandra K.; Figueroa-Valdés, Aliosha I.; Fioretti, Paolo V.; Flenady, Sabine; Flores-Bellver, Miguel; Fok, Ellis K.; Fonseka, Pamali; Ford, Verity J.; Fornaguera, Cristina; Forte, Dorian; Forte, Stefano; Fortunato, Orazio; Franklin, Jeffrey L; Freitas, Daniela; Frelet-Barrand, Annie; Fu, Qing-Ling; Fujita, Yu; Gärtner, Kathrin; Görgens, André; Gabriel, Áurea M.; Gabrielli, Martina; Gabrielsson, Susanne; Galinsoga, Alicia; Galisova, Andrea; Gamage, Teena Kjb; Gao, Yingtang; Garcia-Contreras, Marta; Garcia Garcia, M. Madhy; Garcia, Maria Noé; Gargiulo, Ernesto; Mc Gee, Margaret M.; Genard, Géraldine C.; Geraci, Fabiana; Ghanam, Jamal; Ghatak, Subhadip; Ghavami, Mahlegha; Ghebosu, Raluca E.; Gho, Yong Song; Ghosal, Sayam; Giamas, Georgios; Giebel, Bernd; Gilbert, Caroline; Gimona, Mario; Girão, Henrique; Giusti, Ilaria; Gizzie, Evan A.; Glamočlija, Sofija; Glass, Sarah E.; Gobbo, Jessica; Goberdhan, Deborah Ci; Godbole, Nihar; Goetz, Jacky G.; Gomez-Florit, Manuel; Goncalves, Jenifer Pendiuk; González-King Garibotti, Hernán; Gorgun, Cansu; Gori, Alessandro; Gorska, Sabina; Graner, Michael W.; Grau, Georges E.; Grech, Laura; Greening, David W.; Groß, Rüdiger M.; Gross, Julia C.; Gruber, Jens; Gualerzi, Alice; Guanzon, Dominic; Gudbergsson, Johann M.; Guerin, Coralie L.; Guerra, Flora; Guillén, Maria I.; Gujar, Vikramsingh; Guo, Wei; Gupta, Veer Bala; Gupta, Vivek Kumar; Gustafson, Dakota; Gyukity-Sebestyén, Edina; Hölker, Patrick; Hade, Mangesh D.; Hagey, Daniel W.; Han, Chungmin; Han, Pingping; Hanayama, Rikinari; Handberg, Aase; Hanser, Edveena; Harada, Masako; Harmati, Maria; Harris, Adrian L.; Harrison, Paul; Harrison, Rane A.; Haughey, Norman J.; Haynes, Paul A; He, Mei; Hegyesi, Hargita; Hendrix, An; Van Herwijnen, Martijn J.; Hill, Andrew F.; Hisey, Colin L.; Hochberg, Fred H.; Hoen, Esther Nm Nolte-'t; Holcar, Marija; Holder, Beth; Holnthoner, Wolfgang; Holthofer, Harry; Hooper, D. Craig; Hosseini-Behesht, Elham; Hosseinkhani, Baharak; Howard, Jane; Howe, Kathryn L.; Hoyle, Nicholas R.; Hrdy, Jiri; Hu, Guoku; Huang, Yiyao; Huber, Veronica; Hudoklin, Samo; Hufnagel, Antonia; Hulett, Mark D.; Hunt, Stuart; Hyenne, Vincent; Ianni, Emilio Di; Iannotta, Dalila; Ibrahim, Ahmed Ge; Ibrahim, Sherif A.; Ikezu, Seiko; Ikezu, Tsuneya; Im, Hyungsoon; Inal, Jameel M; Inic-Kanada, Aleksandra; Inngjerdingen, Marit; Inoshima, Yasuo; Ivanov, Alexander R.; Ivanova, Alena; Izquierdo, Elena; Jørgensen, Malene Møller; Jackson, Hannah K.; Jacobsen, Soren; Jadue, Fernanda; Javeed, Naureen; Jay, Steven M.; Jayachandran, Muthuvel; Jayasinghe, Migara K.; Jenster, Guido; Jeppesen, Dennis K.; Jerónimo, Carmen; Jiang, Linglei; Jin, Jing; Jingushi, Kentaro; Jo, Dong-Gyu; Joerger-Messerli, Marianne S.; Jones, Jennifer C.; de Jong, Olivier G.; Jovanovic-Talisman, Tijana; Ferrante Jr, Anthony W.; Coleman Jr, Leon G.; Juncker, David; Jung, Stephanie; Jurek, Benjamin; Jurga, Marcin; Justilien, Verline; Kabani, Mehdi; Kalluri, Raghu; Kamali-Moghaddam, Masood; Kanada, Masamitsu; Kang, Taeyoung; Kano, Shin-Ichi; Kaparakis-Liaskos, Maria; Karnas, Elżbieta; Karoichan, Antoine; Kashanchi, Fatah; Kashani, Sara Assar; Kashyap, Namita N.; Katsur, Miroslava; Kau-Strebinger, Silvio; Kauffman, Amy C.; Kaur, Sukhbir; Kehoe, Oksana; Kelwick, Richard Jr; Kenari, Amirmohammad Nasiri; Kestecher, Brachyahu M.; Keulers, Tom G.; Van Keuren-Jensen, Kendall R.; Khalajx, Kasra; Khamari, Delaram; Khanabdali, Ramin; Khomyakova, Elena; Khoo, Amanda; Kim, Daniel H.; Kim, Dongin; Kim, Han Sang; Kim, In-San; Kim, Soo; Kim, Yohan; Kima, Peter E.; Kislinger, Thomas; Klingeborn, Mikael; Komuro, Hiroaki; Koncz, Anna; Konstantinou, Timothea; Van der Koog, Luke; Kooijmans, Sander Aa; Kornek, Miroslaw T.; Kosanović, Maja; Kostallari, Enis; Koukoulis, Tiana F.; Kourembanas, Stella; Krämer-Albers, Eva-Maria; Kralj-Iglic, Veronika; Krasemann, Susanne; Krasnodembskaya, Anna D.; Krawczynska, Natalia J.; Kreft, Mateja E.; Kruh-Garcia, Nicole A.; Kuehn, Meta J.; Kuipers, Marije E.; Kulaj, Konxhe; Kuligowski, Julia; Kumagai, Yumi; Kumar, Ashish; Kumar, Saroj; Kumar, Sharad; Kumari, Meena; Kundrotas, Gabrielis; Kurochkin, Igor V.; Kuroda, Masahiko; Kurzawa-Akanbi, Marzena; Kweskin, Sasha J.; Kyburz, Diego; Lázaro-Ibáñez, Elisa; Lässer, Cecilia; Lötvall, Jan; Lőrincz, Ákos M.; Lai, Andrew; Lai, Charles P.; Laitinen, Saara; Landreville, Solange; Lange, Sigrun; Langevin, Scott M.; Langlois, Marc-André; Languino, Lucia R.; Lannigan, Joanne; Lark, Daniel S.; Larregina, Adriana T.; Laurent, Louise C.; Laurin, David; Lavieu, Gregory; Lawson, Charlotte; Lay, Soazig Le; Leandrox, Kevin; Ledreux, Aurélie; Lee, Changjin; Lee, Dong-Sup; Lee, Hakho; Lee, Heon-Jin; Lee, Sun Young; Lee, Tae Ryong; Lee, Wai-Leng; Lefterov, Iliya; Lei, Xinhua; Leivo, Janne; Lemaire, Quentin; Leme, Adriana F Paes; Lemon, Stanley M.; Lenassi, Metka; Lennon, Kathleen M.; Lenzini, Stephen; Leor, Jonathan; Levy, Efrat; Li, Guoping; Li, Jiao Jiao; Li, Qiubai; Li, Xinlei; Liang, Xiuming; Lim, Rebecca; Lim, Sai Kiang; Limongi, Tania; Linē, Aija; Lins, Paula Pincela; Lippens, Lien; Liu, Guanshu; Llorente, Alicia; Longjohn, Modeline N.; de Loo, Fons Aj van; Lorenowicz, Magdalena J.; Lorico, Aurelio; Loudig, Olivier; Loyer, Xavier; Lozano-Andrés, Estefanía; Lu, Biao; Lu, Quan; Lubart, Quentin; Lucien, Fabrice; Lunavat, Taral R.; Lundberg, Ludwig Ermann; Lundy, David J.; Luoto, Jens C.; Lyden, David C.; Möller, Andreas; Müller, Janis A.; MacPhee, Daniel J.; Maddox, Adam L.; Madec, Elise; Magaña, Setty M.; Mahairaki, Vasiliki; Mahoney, Mỹ G.; Malhi, Harmeet; Malnou, Cécile E.; Mamand, Doste R.; Man, Kenny; Manno, Mauro; Mantel, Pierre-Yves; Marangon, Tecla; Marbán, Eduardo; Marcilla, Antonio; Maremanda, Krishna P.; Margolis, Leonid; Mariñas-Pardo, Luis; Marić, Ivica; Martín, Silvia Sánchez; Martínez-Martínez, Eduardo; Martel, Catherine; Martens-Uzunova, Elena S; Martin-Duque, Pilar; Martin-Jaular, Lorena; Martinez-Murillo, Paola A.; Martinez-Pacheco, Sarai; Martins-Marques, Tania; Mary, Benjamin; Marzan, Akbar L.; Matamoros-Angles, Andreu; Mathivanan, Suresh; Matsuzaki, Juntaro; Mayan, Maria D.; Mazzeo, Carla; Mbengue, Mariama; McCann, Mark J.; McIlvenna, Luke C.; McVey, Mark J.; Meisner-Kober, Nicole; Mellergaard, Maiken; Melli, Giorgia; Menck, Kerstin; Menjivar, Nico G.; Menon, Ramkumar; Mentkowski, Kyle I.; Miklavcic, John J.; Miklosi, Andras G.; Milutinovic, Bojana; Minciacchi, Valentina R.; Mirzaei, Mehdi; Mishra, Shalini; Mitchell, Megan I.; Mizenko, Rachel R.; Mladenović, Danilo; Mohamadi, Eqbal; Mohanty, Sujata; Momen-Heravi, Fatemeh; Mondal, Sujan K.; Monguió-Tortajada, Marta; Moon, Jisook; Morandi, Mattia I.; Moreau, Violaine; Morelli, Adrian E.; Mori, Marcelo A.; Morimoto, Masahiro; Mosser, Mathilde; Motaung, Thabiso Eric; Moussay, Etienne; Mugoni, Vera; Mullier, Francois; Muraca, Maurizio; Mullier, Francois
Extracellular vesicles (EVs), through their complex cargo, can reflect the state of their cell of origin and change the functions and phenotypes of other cells. These features indicate strong biomarker and therapeutic potential and have generated broad interest, as evidenced by the steady year-on-year increase in the numbers of scientific publications about EVs. Important advances have been made in EV metrology and in understanding and applying EV biology. However, hurdles remain to realising the potential of EVs in domains ranging from basic biology to clinical applications due to challenges in EVnomenclature, separation from non-vesicular extracellular particles, characterisation and functional studies. To address the challenges and opportunities in this rapidly evolving field, the International Society for Extracellular Vesicles (ISEV) updates its ‘Minimal Information for Studies of Extracellular Vesicles’, which was first published in 2014 and then in 2018 as MISEV2014 and MISEV2018, respectively. The goal of the current document, MISEV2023, is to provide researchers with an updated snapshot of available approaches and their advantages and limitations for production, separation and characterisation of EVs from multiple sources, including cell culture, body fluids and solid tissues. In addition to presenting the latest state of the art in basic principles of EV research, this document also covers advanced techniques and approaches that are currently expanding the boundaries of the field. MISEV2023 also includes new sections on EV release and uptake and a brief discussion of in vivo approaches to study EVs. Compiling feedback from ISEV expert task forces and more than 1000 researchers, this document conveys the current state of EV research to facilitate robust scientific discoveries and move the field forward even more rapidly.
Managing African armyworm outbreaks in sub-Saharan Africa : current strategies and future directions
(MDPI, 2025-06) Kinyanjui, Grace; Mawcha, Kahsay Tadesse; Malinga, Lawrence Nkosikhona; Soobramoney, Kaitlyn; Nethononda, Phophi; Assefa, Yoseph; Okonkwo, Chibuzor Onyinye; Ndolo, Dennis; phophi.nethononda@fabi.up.ac.za
The African armyworm Spodoptera exempta (Lepidoptera: Noctuidae) is a significant pest that affects cereal crops and pasture grasses in sub-Saharan Africa. This migratory pest causes extensive defoliation, which can result in significant yield losses, particularly in maize. This review focuses on the recent outbreaks of the African armyworm and identifies key factors contributing to its success across sub-Saharan Africa. Understanding these factors is essential for developing effective and sustainable pest management strategies. This review emphasizes the importance of innovative technologies and data-driven approaches in managing pest outbreaks and underscores the need to implement technology-enabled integrated pest management (IPM) strategies to control the African armyworm effectively. SIMPLE SUMMARY The African armyworm is a destructive, migratory pest that threatens cereal crops and pasture grasses in sub-Saharan Africa, with recent outbreaks resulting in significant agricultural and economic losses. This review addresses the urgent need for improved management strategies by examining the drivers of frequent outbreaks, including climate change, the pest’s biological traits, and gaps in current control practices. This paper aims to evaluate existing surveillance and control methods—such as chemical, biological, and cultural approaches—and to explore innovative technologies, including predictive modeling, artificial intelligence, Bt maize technology, molecular biology, and nanotechnology. This study finds that, while traditional methods offer some control, their limitations necessitate integrated, technology-enabled pest management solutions. It concludes that adopting holistic, regionally coordinated strategies that incorporate farmer education, advanced tools, and updated policy frameworks will significantly improve outbreak response and mitigation. These findings are valuable to society as they provide a roadmap for sustainable pest control, helping to safeguard food security, support farmer livelihoods, and enhance agricultural resilience in the face of escalating climate and pest pressures.
Understanding the genetics of sex determination in insects and its relevance to genetic pest management
(Wiley, 2025-06) Ashmore, Jade Sabrina; Slippers, Bernard; Duong, Tuan A.; Dittrich-Schroder, Gudrun; gudrun.dittrich@fabi.up.ac.za
Sex determination pathways regulate male and female-specific development and differentiation and offer potential targets for genetic pest management methods. Insect sex determination pathways are comprised of primary signals, relay genes and terminal genes. Primary signals of coleopteran, dipteran, hymenopteran and lepidopteran species are highly diverse and regulate the sex-specific splicing of relay genes based on the primary signal dosage, amino acid composition or the interaction with paternally inherited genes. In coleopterans, hymenopterans and some dipterans, relay genes are Transformer orthologs from the serine-arginine protein family that regulate sex-specific splicing of the terminal genes. Alternative genes regulate the splicing of the terminal genes in dipterans that lack Transformer orthologs and lepidopterans. Doublesex and Fruitless orthologs are the terminal genes. Doublesex and Fruitless orthologs are highly conserved zinc-finger proteins that regulate the expression of downstream proteins influencing physical traits and courtship behaviours in a sex-specific manner. Genetic pest management methods can use different mechanisms to exploit or disrupt female-specific regions of different sex determination genes. Female-specific regions of sex determination genes can be exploited to produce a lethal gene only in females or disrupted to impede female development or fertility. Reducing the number of fertile females in pest populations creates a male-biased sex ratio and eventually leads to the local elimination of the pest population. Knowledge on the genetic basis of sex determination is important to enable these sex determination pathways to be exploited for genetic pest management.
A checklist of South African bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae, Platypodinae)
(Magnolia Press, 2025-06) Nel, Wilma Janine; Duong, Tuan A.; Fell, Shaw; Herron, Darryl A.; Paap, Trudy; Wingfield, Michael J.; De Beer, Z. Wilhelm; Hulcr, Jiri; Johnson, Andrew J.; janine.nel@fabi.up.ac.za
No abstract available.
Host-pathogen interactions in the pine-Fusarium circinatum pathosystem and the potential for resistance deployment in the field
(Wiley, 2025-04) Woodward, S.; Amin, H.; Martín-García, J.; Solla, A.; Diaz-Vazquez, R.; Romeralo, C.; Alves, A.; Pinto, G.; Herron, D.; Fraser, S.; Zas, R.; Doğmuş-Lehtijärvi, H.T.; Bonello, P.; Wingfield, Michael J.; Witzell, J.; Diez, J.J.
Pine pitch canker (PPC) emerged as a significant problem in 1945 in Southeastern USA. The causal agent, Fusarium circinatum, has spread widely and now occurs in pine forests and plantations worldwide. Fusarium circinatum causes damping off, shoot and tip die-back, and the death of seedlings in nurseries. Infection of mature trees leads to excessive resin bleeding on branches and main stems, sunken cankers with bark remaining attached, and finally, tree death. Arguably, F. circinatum is the most important pathogen of pine seedlings in many areas of the world. At least 67 species of Pinus, 18 Pinus hybrids, and 6 other non-pine tree species are susceptible to PPC. The selection and development of tree germplasm resistant to pathogens is considered the most robust approach to reduce losses to diseases. Genetic variation in resistance to F. circinatum certainly exists, even in generally very susceptible hosts, such as P. radiata. Exploiting genetic resistance as a tool to manage PPC requires screening large numbers of tree genotypes and fine-tuning efficient phenotyping protocols. The greater the number of genetic lines and replications, the higher the selection differentials and accuracy of the genetic parameter estimates. Recent advances in physiological and molecular techniques exploring the plant-pathogen interaction have expanded our understanding of genetic resistance mechanisms in pines to PPC and represent an added-value tool to support phenotypic selection. This review provides an overview of current knowledge on the molecular, physiological, and genetic basis of resistance to F. circinatum in pines and considers possibilities to improve the resistance of pines against the pathogen through breeding and selection.
Cryphonectria Canker on Eucalyptus in Florida reconsidered
(Wiley, 2025-08) Pham, Nam Q.; Wingfield, Brenda D.; Marincowitz, Seonju; Brawner, Jeremy T.; Hulcr, Jiri; Wingfield, Michael J.; nam.pham@fabi.up.ac.za
Cryphonectria canker is one of the most important diseases of plantation-grown Eucalyptus spp. in the tropics and Southern Hemisphere. The disease has been known in Florida, USA, for many years, and the causal agents are attributed to two known canker pathogens, Chrysoporthe cubensis (≡ Cryphonectria cubensis) and Microthia havanensis (≡ Endothia havanensis). These identifications were based on morphological characteristics, which are inadequate to recognise cryptic species in the Cryphonectriaceae. In this study, we visited various sites in Florida where Eucalyptus grandis and E. amplifolia trees are cultivated and investigated the presence of cankers. Isolations were made from fungal structures on symptomatic tissues associated with cankers. A total of 41 cultures resembling Cryphonectriaceae spp. were isolated. The isolates were identified based on DNA sequences for the ITS region of the rRNA and sections of the β-tubulin gene, and confirmed as the three species of Cryphonectriaceae, namely Microthia havanensis, Chrysoporthe cubensis and Chrysoporthe doradensis. Of these, Chrysoporthe doradensis was discovered for the first time in the USA. In addition, this study represents the first record of any Cryphonectriaceae on E. amplifolia , a Eucalyptus species that is poorly studied in terms of disease. Pathogenicity trials on Eucalyptus showed that all three Cryphonectriaceae species could cause disease on these trees, with Chrysoporthe spp. being more aggressive. These findings highlight the importance of continuous monitoring and surveillance to detect emerging pathogens and safeguard the sustainability of Eucalyptus in non-native forestry systems.
Fungal Planet description sheets : 1697–1780
(Westerdijk Fungal Biodiversity Institute, 2024-12-06) Crous, Pedro W.; Wingfield, Michael J.; Jurjević, Ž.; Balashov, S.; Osieck, E.R.; Marin-Felix, Y.; Luangsa-ard, J.J.; Mejía, L.C.; Cappelli, A.; Parra, L.A.; Lucchini, G.; Chen, J.; Moreno, G.; Faraoni, M.; Zhao, R.L.; Weholt, Ø.; Borovička, J.; Jansen, G.M.; Shivas, R.G.; Tan, Y.P.; Akulov, A.; Alfenas, A.C.; Alfenas, R.F.; Altés, A.; Avchar, R.; Barreto, R.W.; Catcheside, D.E.A.; Chi, T.Y.; Esteve-Raventós, F.; Fryar, S.C.; Hanh, L.T.M.; Larsbrink, J.; Oberlies, N.H.; Olsson, L.; Pancorbo, F.; Raja, H.A.; Thanh, V.N.; Thuy, N.T.; Ajithkumar, K.; Akram, W.; Alvarado, P.; Angeletti, B.; Arumugam, E.; Atashi Khalilabad, A.; Bandini, D.; Baroni, T.J.; Barreto, G.G.; Boertmann, D.; Akram, W.; Alvarado, P.; Angeletti, B.; Arumugam, E.; Atashi Khalilabad, A.; Bandini, D.; Baroni, T.J.; Barreto, G.G.; Boertmann, D.; Bose, Tanay; Castañeda Ruiz, R.F.; Couceiro, A.; Cykowska-Marzencka, B.; Dai, Y.C.; Darmostuk, V.; Da Silva, S.B.G.; Dearnaley, J.D.W.; De Azevedo Santiago, A.L.C.M.; Declercq, B.; De Freitas G. , L.W.S.; De la Peña-Lastra, S.; Delgado, G.; De Lima, C.L.F.; Dhotre, D.; Dirks, A.C.; Eisvand, P.; Erhard, A.; Ferro, L.O.; García, D.; García-Martín, A.; Garrido-Benavent, I.; Gené, J.; Ghobad-Nejhad, M.; Gore, G.; Gunaseelan, S.; Gusmão, L.F.P.; Hammerbacher, Almuth; Hernández-Perez, A.T.; Hernández-Restrepo, M.; Hofmann, T.A.; Hubka, V.; Jiya, N.; Kaliyaperumal, M.; Keerthana, K.S.; Ketabchi, M.; Kezo , K.; Knoppersen, Rosa; Kolarczyková, D.; Kumar, T.K.A.; Læssøe, T.; Langer, E.; Larsson, E.; Lodge, D.J.; Lynch, M.J.; Maciá-Vicente, J.G.; Mahadevakumar, S.; Mateos, A.; Mehrabi-Koushki, M.; Miglio, B.V.; Noor, A.; Oliveira, J.A.; Pereira, O.L.; Piątek, M.; Pinto, A.; Ramírez, G.H.; Raphael, B.; Rawat, G.; Renuka, M.; Reschke, K.; Ruiz Mateo, A.; Saar, I.; Saba, M.; Safi, A.; Sánchez, R.M.; Sandoval-Denis, M.; Savitha, A.S.; Sharma, A.; Shelke, D.; Sonawane, H.; Souza, M.G.A.P.; Stryjak-Bogacka, M.; Thines, M.; Thomas, A.; Torres-Garcia, D.; Traba, J.M.; Vauras, J.; Vermaas, M.; Villarreal, M.; Vu, D.; Whiteside, E.J.; Zafari, D.; Starink-Willemse, M.; Groenewald, J.Z.; Akram
Novel species of fungi described in this study include those from various countries as follows: Antarctica, Leuconeurospora bharatiensis from accumulated snow sediment sample. Argentina, Pseudocercospora quetri on leaf spots of Luma apiculata. Australia, Polychaetomyces verrucosus on submerged decaying wood in sea water, Ustilaginoidea cookiorum on Scleria levis, Xylaria guardiae as endophyte from healthy leaves of Macaranga tanarius. Belgium, Iodophanus taxi on leaf of Taxus baccata. Belize, Hygrocybe mirabilis on soil. Brazil, Gongronella irregularis from soil, Linodochium splendidum on decaying sheath of Euterpe oleracea, Nothophysalospora agapanthi (incl. Nothophysalospora gen. nov.) on flower stalks of Agapanthus praecox, Phaeosphaeria tabebuiae on leaf of Tabebuia sp., Verrucohypha endophytica (incl. Verrucohypha gen. nov.) from healthy roots of Acrocomia aculeata. Estonia, Inosperma apricum on soil under Quercus robur. Greece, Monosporascus solitarius isolated from surface-sterilised, asymptomatic roots of Microthlaspi perfoliatum. India, Diaporthe neocapsici on young seedling stems of Capsicum annuum, Fuscoporia naditirana on dead wood, Sebacina spongicarpa on soil, Torula kanvae from the gut of a Copris signatus beetle. Iran, Sarcinomyces pruni from twig and petiole tissues of Prunus persica and Prunus armeniaca, Xenodidymella quercicola from leaf spots of Quercus brantii. Italy, Agaricus aereiceps on grass, Agaricus bellui in meadows, Agaricus fabrianensis in urban grasslands, Beaucarneamyces muscorum on moss growing in forest, Xenoanthostomella quercus on leaf litter of Quercus ilex. Netherlands, Alfaria neerlandica on stem lesions of Cortaderia selloana, Neodictyosporium juncicola on culms of Juncus maritimus, Penicillium geertdesnooi from soil under Papaver rhoeas, Russula abscondita on rich calcareous soil with Quercus, Russula multiseptata on rich clay soil with Quercus, Russula purpureopallescens on soil with Populus, Sarocladium caricicola on leaves of Carex riparia. Pakistan, Circinaria shimlaensis on limestone rocks. Panama, Acrocalymma philodendri on leaf spots of Philodendron sp., Caligospora panamaensis on leaf litter, Chlamydocillium simulans associated with a Xylaria sp., Corynesporina panamaensis on leaf litter, Cylindromonium panamaense on twig litter of angiosperm, Cyphellophora panamaensis on twig litter of angiosperm, Microcera panamensis on leaf litter of fern, Pseudotricholoma pusillum in tropical montane forest dominated by Quercus spp., Striaticonidium panamaense on leaf litter, Yunnanomyces panamaensis on leaf litter. Poland, Albocremella abscondita (incl. Albocremella gen. nov.) from rhizoids of liverwort Conocephalum salebrosum. Portugal, Agaricus occidualis in meadows. South Africa, Alternaria elsarustiae on culms of unidentified Poaceae, Capronia capensis on dead twig of unidentified angiosperm, Codinaeella bulbinicola on dead leaves of Bulbine frutescens, Cytospora carpobroticola on leaf of Carpobrotus quadrifidus, Neophaeomoniella watsoniae on leaf of Watsonia sp., Neoplatysporoides aloigena on leaf of Aloe khamiesensis, Nothodactylaria comitabilis on living leaf of Itea rhamnoides, Nothopenidiella beaucarneae (incl. Nothopenidiella gen. nov.) on dead leaves of Beaucarnea stricta, Orbilia kirstenboschensis on dead flower stalks of Agapanthus praecox, Phragmocephala agapanthi on dead flower stalks of Agapanthus praecox, Podocarpigena hagahagaensis (incl. Podocarpigena gen. nov.) on leaf spots of Podocarpus falcatus, Sporisorium enterogonipteri from the gut of Gonipterus sp., Synnemapestaloides searsiae on leaf of Searsia populifolia, Xenophragmocapnias diospyri (incl. Xenophragmocapnias gen. nov.) on leaf spots of Diospyros sp., Yunnanomyces hagahagaensis on leaf spots of Sideroxylon inerme. Spain, Agaricus basicinctus in meadows, Agaricus quercetorum among leaf litter in oak forests, Coprinopsis palaciosii on degraded woody debris, Inocybe complutensis in calcareous loamy soil, Inocybe tanitiae in calcareous sandy soil, Mycena subfragosa on dead leaves of Salix atrocinerea, Pseudobaeospora cortegadensis in laurel forests, Trichoderma sedimenticola from fluvial sediments. Sweden, Inocybe badjelanndana on calcareous soil. Ukraine, Beaucarneamyces lupini on overwintered stems of Lupinus polyphyllus, Protocreopsis globulosa on thallus and apothecia of Lecania cyrtella on bark of Populus sp., Thyridium tiliae on dead twigs of Tilia sp. USA, Cladosporium louisianense, Cyphellophora americana from a bedroom vent, Extremus massachusettsianus from lyse buffer, Myxotrichum tapetae on carpet in basement, Neospissiomyces floridanus (incl. Neospissiomyces gen. nov.) on swab from hospital, Polychaetomyces marinus (incl. Polychaetomyces gen. nov.) on submerged driftwood in sea water, Steccherinum fragrans on hardwood fallen on the beach, Steinbeckomyces carnegieae (incl. Steinbeckomyces gen. nov.) on Carnegiea gigantea, Tolypocladium pennsylvanicum from air sampled in basement. Vietnam, Acidomyces ducanhii from Aglaia flowers, Acidomyces paludis from dead bark of Acacia sp., Phakopsora sageretiae on Sageretia theezans, Puccinia stixis on Stixis scandens. Morphological and culture characteristics are supported by DNA barcodes
Bacterial fruit tree quarantine pathogens – a threat to biosecurity in South Africa
(Academy of Science of South Africa, 2025-09) Coutinho, Teresa A.; teresa.coutinho@up.ac.za
Quarantine bacterial plant pathogens present a serious threat to the biosecurity of South Africa’s fruit tree industry, posing significant risks to agricultural productivity, trade and biodiversity. Pathogens such as Candidatus Liberobacter asiaticus, Xanthomonas citri pv. citri, Erwinia amylovora and Xylella fastidiosa can cause widespread economic losses in fruit crops, including citrus, apples, pears, grapes and olives. Managing these pathogens is challenging due to their ability to spread rapidly, often by the movement of infected plant material and/or by insect vectors. Limited diagnostic capabilities, few chemical control options, and the emergence of pathogen resistance also hamper effective management. This review highlights the importance of an integrated approach should an incursion occur, which would initially involve eradication, improved surveillance and public awareness. Strengthening these biosecurity practices is essential in safeguarding the agricultural sector and ensuring continued fruit trade viability. SIGNIFICANCE : • This review highlights the significant threat posed by quarantine bacterial fruit tree pathogens to South Africa’s agricultural biosecurity. These pathogens endanger essential fruit crops, and an outbreak could lead to severe losses, trade restrictions, and socio-economic impacts. • The review also highlights the challenges that would likely be faced if an incursion should occur. It advocates for an integrated management approach including eradication, surveillance, public awareness, and robust phytosanitary measures, legislative support and inter-agency collaboration. This approach could ensure that we safeguard the agricultural sector and mitigate potential crises.
Pathogenicity of Pythium myriotylum on Acacia crassicarpa and Acacia mangium x Acacia auriculiformis clones in Indonesia
(Taylor and Francis, 2025) Tarigan, Marthin; Wingfield, Michael J.; Jami, Fahimeh; Oliveira, Leonardo S.S.; Saha, Muhammad A.; Duran, Alvaro; Pham, Nam Q.; nam.pham@fabi.up.ac.za
The oomycete Pythium myriotylum is an important pathogen of several crops, causing wilt and damping-off during nursery propagation. The pathogen was recently reported as the causal agent of wilt and damping-off on Acacia crassicarpa plants in nurseries located in Riau, Indonesia. The aim of this study was to evaluate the relative pathogenicity of P. myriotylum on different clones of A. crassicarpa and Acacia mangium × Acacia auriculiformis hybrids. Based on the results, greater tolerance was found on the A. mangium × A. auriculiformis hybrid clones than on those of pure A. crassicarpa. The different Acacia clones also displayed different levels of tolerance of infection. Overall the results showed that screening for tolerance to infection by P. myriotylum will be important in the Acacia breeding programme and make it possible to produce sufficient nursery stock for plantation establishment.
The re-identification of Penicillium and Talaromyces (Eurotiales) catalogued in South African culture collections
(National Herbarium of the Netherlands, 2024-12) Visagie, Cobus M.; Houbraken, J.; Yilmaz, Neriman; cobus.visagie@fabi.up.ac.za
The taxonomy of Penicillium and Talaromyces has been modernized in the past decade, resulting in more robust and accurate identifications, while hundreds of new species were described from around the world. South Africa has emerged as somewhat of a biodiversity hotspot for these genera, with 48 new species being described in recent years. The aim of this current project was to re-identify Penicillium and Talaromyces strains held in South African culture collections, including the National Collections of Fungi (PPRI) and the Medical Research Council (MRC). A total of 295 PPRI and 56 MRC strains were revived and identified using β-tubulin (BenA) gene sequences. For new or rarely found species, we also sequenced the rDNA internal transcribed spacer regions (ITS), calmodulin (CaM), and RNA polymerase second largest subunit (RPB2) genes. The strains were identified to 99 Penicillium and 25 Talaromyces species, among them eight new Penicillium and three new Talaromyces species. Morphological comparisons with close relatives confirmed the novelty of these species, and they are formally described here as P. drakensteinense, P. kirstenboschense, P. limpopoense, P. lydenburgense, P. mbombelaense, P. potchefstroomense, P. roodeplaatense, P. silvertonense, T. gautengensis, T. macrodendroideus, and T. mzansiensis. This study provides a much-needed update on species diversity captured in South African culture collections and makes an important contribution to international knowledge on these important genera.
Bio-control efficacy of selected indigenous nematophagous fungi against Meloidogyne enterolobii in vitro and on dry bean (Phaseolus vulgaris L.)
(Springer, 2025-05) Ramatsitsi, Ndivhuwo; Dube, Zakheleni Palane; Ramachela, Khosi; Motloba, Tuelo
Dry bean (Phaseolus vulgaris L.) is an important commercialized field crop in South Africa for aiding in food security as a cheap protein source. However, it is highly susceptible to root-knot nematodes (RKN), Meloidogyne species. Use of indigenous nematophagous fungi as bio-control agents (BCA) of Meloidogyne nematodes is a promising research focus area. This is because indigenous fungal species are naturally part of the ecosystem and therefore compatible with other biological processes unlike most synthetic chemicals. The objective of the study was to identify indigenous nematophagous fungal BCA and establish their potential efficacy in reducing M. enterolobii population densities on dry bean with and without incorporation of compost. Screened indigenous fungal species included Aspergillus terreus, Talaromyces minioluteus, T. sayulitensis, Trichoderma ghanense, and T. viride. There were observed significant parasitism differences (P ≤ 0.05) among the BCA, with T. ghanense showing the highest egg parasitism (86%), followed by T. minioluteus (72%) and T. sayulitensis (70%). On the other hand, the highest J2 parasitism was observed on T. minioluteus (95%), followed by A. terreus and T. viride (63%). A similar trend was observed under in vivo conditions, with higher efficacy with compost incorporation. This provides a highly encouraging alternative and ecologically complementary Meloidogyne management in dry bean production.
Biofilm characterisation of the maize rot-causing pathogen, Fusarium verticillioides
(Taylor and Francis, 2025) Peremore, Chizne; Van't Hof, Cairin; Nkosi, Cebo-LeNkosi; Tshiyoyo, Kadima Samuel; Ratsoma, Francinah M.; Kola, Wisely; Malgas, Samkelo; Santana, Quentin C.; Wingfield, Brenda D.; Steenkamp, Emma Theodora; Motaung, Thabiso Eric; thabiso.motaung@up.ac.za
Biofilm formation was investigated in a maize rot-causing pathogen, Fusarium verticillioides. This work revealed that in vitro cultures produce structured, adherent communities with a dense extracellular matrix (ECM) surrounding hyphae that makes up the biomass of a matured biofilm. Pellicle containing exopolysaccharide had a hydrodynamic diameter of 4.19 nm and a low viscosity (0.022 dl/g). The exopolysaccharide was composed of amino sugars and unordered, facilitating stability through complexation with the anionic eDNA. Biofilm formation varied over different pH and temperature values, emphasising its role in promoting adaption, survival, and persistence in F. verticillioides, potentially contributing to its pathogenicity in maize. Collectively, the results provide valuable insights into biofilm structure and stress resistance in this fungus, and will serve as a foundation for future studies incorporating in planta infection systems.
Small RNAs derived from avocado sunblotch viroid and their association with bleaching symptoms : implications for pathogenesis in avocado sunblotch disease
(Springer, 2025-09) Joubert, Melissa; Van den Berg, Noelani; Theron, Jacques; Swart, Velushka; velushka.swart@fabi.up.ac.za
Avocado sunblotch viroid (ASBVd) is a structured RNA molecule responsible for sunblotch disease of avocado, characterised by distinct chloroses of fruit, leaves, and stems. Despite its impact on avocado, the mechanism by which ASBVd elicits sunblotch symptoms remains unknown. Previous studies on other avsunviroids have shown that viroid-derived small RNAs (vd-sRNAs) with specific sequence mutations can trigger leaf chlorosis via RNA silencing of host genes. Building on this knowledge, we aimed to shed light on the molecular basis of ASBVd pathogenesis by analysing ASBVd sequence variants and ASBVd-sRNAs from bleached and asymptomatic leaf tissues of sunblotch-affected avocado trees. Sequencing of ASBVd clones revealed that variants carrying the pathogenic determinant for bleaching were present in both green and yellow leaf tissues. Next-generation sequencing (NGS) identified ASBVd-sRNAs that varied in abundance between symptomatic and asymptomatic leaf tissues, correlating with viroid titre. We discovered 64 vd-sRNAs spanning the pathogenic region of the ASBVd genome, which were almost exclusively found in yellow tissues. The ASBVd-sRNAs containing the bleaching-associated mutation were predicted to target numerous avocado transcripts for degradation, with 25 of these transcripts significantly downregulated in bleached tissues. Notably, one of these genes, encoding a chloroplastic protein, demonstrated strong evidence of ASBVd-sRNA-guided RNA silencing, presenting a promising candidate for future research into the molecular trigger for ASBVd-induced bleaching symptoms. This study is the first to investigate ASBVd-sRNAs in bleached leaves using NGS. Our findings support the role of RNA silencing in sunblotch symptom development and reveal a unique silencing trigger compared to other avsunviroids.
Factors influencing the capture of Japanese beetles : wind speed and direction, trap deployment protocol, lure type, and trap efficiency
(Oxford University Press, 2025-07) Guignard, Quentin; Goodwin, Joel; Kimoto, Troy; Haynes, Kenneth F.; Allison, Jeremy D.
In this study, factors affecting Japanese beetle (JB) trap captures (eg wind direction and speed, lure type, trap deployment and efficiency) were investigated in the field using semiochemical baited traps. Fifty-two percent of 667 JB observed flew directly upwind toward a trap with a dual lure (sex pheromone + floral kairomone), especially when wind speed exceeded 1.5 m/s. Within thirty seconds after approaching 2 m of a trap baited with a dual lure, 43%, 35%, and 22% of 138 observed beetles were captured, flew away, or landed on the trap, respectively. Of 265,884 beetles captured, 48% were captured by a cluster of 3 traps each with a single dual lure, 30% by a single trap baited with 3 dual lures, and 22% by a single trap baited with one dual lure. Traps baited with the floral lure (ie kairomone) and the floral lure and the sex pheromone (ie dual lure) captured similar numbers (39% and 41%, respectively) of JB and both captured more beetles than traps baited with the pheromone alone (12% and 8% for the sex-pheromone from the dual lure and sex-pheromone standard, respectively). Traps baited with the floral kairomone alone or with sex pheromone captured a 1:1 sex ratio (M:F) while pheromone-only traps captured a 3:1 (M:F) ratio of JB. No additive or synergistic effects of the pheromone and floral kairomone were observed. To our knowledge, this study is the first to quantify in real time the flight behavior of a beetle toward traps in the field.

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