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

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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.
Ewingella allii sp. nov. isolated from a diseased onion plant in the Columbia Basin of Washington State, USA
(Springer, 2025-07) Mnguni, Fanele Cabangile; Shin, Gi Yoon; Du Toit, Lindsey J.; Derie, Michael L.; Coutinho, Teresa A.; teresa.coutinho@up.ac.za
Please read abstract in the article.
Design of genus-specific semi-nested primers for simple and accurate identification of Enterobacter strains
(BioMed Central, 2025-07) Jordan, Sara; Pothier, Joel F.; De Maayer, Pieter; Broders, Kirk; Kvitko, Brian H.; Coutinho, Teresa A.; Smits, Theo H. .
BACKGROUND : The genus Enterobacter, in the family Enterobacteriaceae, is of both clinical and environmental importance. This genus has undergone frequent taxonomic changes, making it challenging to identify taxa even at genus level. This study aimed to design Enterobacter genus-specific primers that can be used for simple PCR identification of large sets of putative Enterobacter isolates. RESULTS : Comparative genomic approaches were employed to identify genes that were universally present on Enterobacter genomes but absent from the genomes of other members of the family Enterobacteriaceae, based on an initial set of 89 genomes. The presence of these genes was further confirmed in 4,276 Enterobacter RefSeq genomes. While no strictly genus-specific genes were identified, the hpaB gene demonstrated a restricted distribution outside of the genus Enterobacter. Semi-nested primers were designed for hpaB and its flanking gene hpaC (hpaBC) and evaluated on 123 strains in single-tube PCR reactions. All taxa showing positive reactions belonged to the genus Enterobacter. For Enterobacter strains the PCR yielded two amplicons at 110 bp and at 370 bp, while strains only displaying the 110 bp amplicon were classified as Leclercia pneumoniae. A blind-test on 120 strains accessioned as Enterobacter sp. from the USDA-ARS culture collection (NRRL), revealed that one third of the strains had an incorrect genus assignment. Comparison of gene trees of the hpaBC fragment sequences with marker genes frequently used for single-gene barcoding or multi-locus sequence analysis (MLSA) further demonstrated its potential for preliminary species identification. CONCLUSIONS : The nested PCR assay represents a rapid and cost-effective approach for preliminary identification of Enterobacter species. As the primer design was based on large-scale genomic comparison, including currently undescribed species clades, it will remain valid even after taxonomic changes within the genus.
A novel Arthrobotrys species : taxonomic characterization, nematicidal activity, and multi-omics insights into nematode predation
(Elsevier, 2025-09) Gao, Mengting; Yan, Zhaoqi; Liu, Zexin; Jiang, Yunxia; Liu, Tengteng; Miao, Xingjun; Dai, Meixue; Bose, Tanay; tanay.bose@fabi.up.ac.za
ursaphelenchus xylophilus, the pinewood nematode (PWN), is a devastating invasive pest responsible for widespread mortality in global conifer forests. During a survey of bark beetle-associated fungi, a nematode-trapping fungus was isolated from an empty beetle gallery in Pinus thunbergii. ITS sequence analysis suggested it represented a novel species. This study aimed to characterize the fungus taxonomically and evaluate its biocontrol potential against PWN. Multi-locus phylogenetic analyses (ITS, TEF1-α, RPB2) confirmed the isolate as a new species, Arthrobotrys byssisimilis sp. nov. Morphological examination revealed adhesive trapping networks and distinctive ellipsoidal conidia. Enzymatic assays demonstrated chitinase and protease activity, with optimal conditions defined for pH and temperature. Culture filtrates, protein extracts, and secondary metabolites showed rapid, dose-dependent nematicidal effects, achieving 100 % PWN mortality within 10–30 min. The fungus exhibited strong tolerance to pine-derived volatiles (α-pinene, β-pinene, turpentine, and ethanol), indicating high adaptability to the host environment. Whole-genome sequencing revealed a 36.97 Mb genome with 8,354 predicted genes, including 104 proteases, 8 chitinases, and diverse secondary metabolite biosynthesis clusters. Transcriptomic profiling after nematode exposure identified 638 differentially expressed genes, including virulence-related enzymes (proteases, CAZymes), cytochrome P450s, and PHI factors, with evidence of stage-specific regulation. Arthrobotrys byssisimilis is the first Arthrobotrys species reported from a bark beetle gallery, expanding the ecological scope of the genus. The integrated in vitro nematicidal activity, physiological adaptability, and multi-omics data suggest A. byssisimilis warrants further evaluation as a potential biocontrol agent against PWN, while its unique genomic features provide new molecular targets for investigating fungal-nematode interactions. HIGHLIGHTS • Discovered novel nematode-trapping fungus Arthrobotrys byssisimilis. • Achieved 100% pinewood nematode kill in 10–30 mins using culture filtrates and extracts. • Shows strong tolerance to pine volatiles, ensuring better field adaptability. • Genome shows 104 proteases, 8 chitinases as major virulence factors. • Found 638 genes differentially expressed under nematode stress, stage-specific virulence.
Exploring the diversity of leafrollers (Lepidoptera: Tortricidae) associated with eucalypts in South African forestry nurseries and plantations, with a new report of Strepsicrates sp.
(Taylor and Francis, 2024-11-08) Makunde, Privilege Tungamirai; Slippers, Bernard; Hurley, Brett P.; privilege.makunde@fabi.up.ac.za
A number of insect pests cause damage to eucalypts in South Africa. Their accurate identification is a key part of managing and controlling these pests. The aims of this study were to identify leafroller insect species in South African eucalypt nurseries and plantations, and to determine whether the species were native insects that had developed new host associations with eucalypts or introduced non-native species. A section of the mitochondrial cytochrome c-oxidase subunit 1 (CO1) gene of multiple specimens from nurseries and plantations was sequenced. The sequence data were compared and validated using sequences available in BOLD systems and GenBank databases. Results revealed the presence of an introduced non-native Strepsicrates sp. in both nurseries and plantations. In addition, the native species Choristoneura occidentalis and Eccopsis incultana were confirmed as present in plantations only and the native species Lozotaenia capensana was confirmed as present in one of the nurseries. Eucalypts are reported as host plants of C. occidentalis, E. incultana and Lozotaenia capensana for the first time. The findings contribute valuable insights into the identification and diversity of leaf rollers in eucalypt plantations in South Africa, with potential implications for pest management.
DNA sequence data confirms the presence of two closely related cypress-feeding aphid species on African cypress (Widdringtonia spp.) in South Africa
(Taylor and Francis, 2024-12) Wondafrash, Mesfin; Wingfield, Michael J.; Hurley, Brett Phillip; Slippers, Bernard; Mutitu, Eston K.; Jenya, Herbert; Paap, Trudy
Aphids in the genus Cinara (Hemiptera: Aphididae) are pests of coniferous trees globally. Some of these aphids have become invasive in various parts of the world and have led to significant economic and environmental damage. During surveys conducted as part of a sentinel plant project, severe aphid infestations were observed on Widdringtonia trees in the Kirstenbosch National Botanical Garden, Cape Town, South Africa. In addition, planted Widdringtonia wallichii Endl. ex Carrière trees within their natural range of the Cederberg Wilderness Area, Western Cape, South Africa were found infested with aphids. In this study, we investigated the species identity of the aphids using DNA sequence data for the mitochondrial cytochrome coxidase (COI) gene. The results revealed the presence of two closely related aphid species, the cypress aphid, Cinara cupressi (Buckton) and the cypress pine aphid, Cinara tujafilina (Del Guercio) infesting Widdringtonia spp. in South Africa. Both aphid species are alien to South Africa. While this is not the first report for either species in the country, the current study provides evidence of impact, with severe infestations leading to branch dieback and tree death. This finding supports the regulation of Cinara spp. in South Africa and highlights that management is urgently needed.
High genetic diversity and limited regional population differentiation in populations of Calonectria pseudoreteaudii from Eucalyptus plantations
(American Phytopathological Society, 2025-01) Li, WenWen; Liu, Feifei; Chen, ShuaiFei; Wingfield, Michael J.; Duong, Tuan A.
Calonectria pseudoreteaudii causes a serious and widespread disease known as Calonectria leaf blight in Eucalyptus plantations of southern China. Little is known regarding the population biology or reproductive biology of this pathogen in the affected areas. The aims of this study were to investigate the genetic diversity, population structure, and reproductive mode of C. pseudoreteaudii from affected Eucalyptus plantations of southern China. Ten polymorphic simple sequence repeat markers were developed for the species and were used to genotype 311 isolates from eight populations. The mating types of all isolates were identified using the MAT gene primers. The results revealed a high level of genetic diversity of the pathogen in all investigated populations. Of the 90 multilocus genotypes detected, 10 were shared between at least two populations. With the exception of one population from HuiZhou, GuangDong (7HZ), the most dominant genotype was shared in the seven remaining populations. Discriminant analysis of principal components and population differentiation analyses showed that the 7HZ population was well differentiated from the others and that there was no significant differentiation between the remaining populations. Analysis of molecular variance suggested that most molecular variation was within populations (86%). Index of association analysis was consistent with a predominantly asexual life cycle for C. pseudoreteaudii in the studied regions. Although both mating types were detected in seven of the eight populations, the MAT1-1/MAT1-2 ratios in these populations deviated significantly from the 1:1 ratio expected in a randomly mating population.
Advancing forest pathology : the need for community-driven molecular experimental model systems
(Wiley, 2025-08) Oostlander, Anne G.; Fleissner, Andre; Slippers, Bernard; bernard.slippers@fabi.up.ac.za
Forests world-wide are under escalating threat from emerging and invasive fungal and oomycete pathogens, driven by globalization and shifting climate dynamics. Effective strategies to manage the current scale and rate of changes in forest health remain hindered by our limited ability to study the underlying mechanisms of pathogen–host and pathogen–microbiome interactions, especially at a molecular and cellular level, compared to general plant pathology, where experimental and model systems exist. Such models facilitate the integration of diverse methodologies from a broader base of the research community, allowing for a more holistic and deeper examination of complex research questions. Here, we propose a framework for the development of such model systems also for forest pathology. This goal is more feasible than ever, thanks to rapid technological advancements, increasing open data availability and a globally interconnected research community. These factors create a unique opportunity to integrate ecosystem-focused research in forest pathology with a unified model organism strategy. Achieving this goal will require a dedicated community effort in the coming years, as such model systems are not discovered but built.
First report of pepper ringspot virus on potato (Solanum tuberosum) in South Africa
(Springer, 2025-05) Espach, A.; Esterhuizen, L.; Africander, N.; Thiart, S.; Read, David Alan; Pietersen, Gerhard
No abstract available.
Expanding ISME communications to taxonomy and nomenclature
(Oxford University Press, 2025-06) Chuvochina, Maria; Palmer, Marike; Venter, S.N. (Stephanus Nicolaas)
Research in microbial ecology is often accompanied by the classification and naming of new taxa, typically included as part of the results section of an ecological study. Bold and beautiful, Latin names are more than labels—they are essential tools for scientific communication. Nested within a hierarchical system, they populate public databases and enable researchers to search for organisms, retrieve associated sequences and metadata, and explore related taxa across various taxonomic levels. In recognition of the vital role that naming and classification play in ecological studies, ISME Communications is proud to introduce Taxonomy and Nomenclature as part of its scope.
First report of Clavibacter nebraskensis causing Goss's bacterial leaf blight on maize (Zea mays) in South Africa
(American Phytopathological Society, 2025-07) Coertze, Sonja; Coetzee, Beatrix; Basson, Elaine; De Villiers, Dore; Makhura, Tjitjila; Mostert, Diane; Slippers, Bernard; Rose, Lindy J.; Visagie, Cobus M.; Read, David Alan
No abstract available.
Host specificity and host stage preference of Psyllaephagus species (Hymenoptera: Encyrtidae) towards invasive eucalypt psyllids (Hemiptera: Aphalaridae)
(Wiley, 2025-08) Makunde, Privilege Tungamirai; Slippers, Bernard; Bush, Samantha J.; Hurley, Brett Phillip; privilege.makunde@up.ac.za
Invasive eucalypt psyllids pose a threat to the long-term production of eucalypts worldwide. In order to reduce their economic impact, classical biological control using Psyllaephagus species has been used successfully. The objectives of this study were to determine the host specificity and host stage preference of Psyllaephagus blastopsyllae, Psyllaephagus pilosus and Psyllaephagus bliteus using related eucalypt-feeding psyllids, Blastopsylla occidentalis, Ctenarytaina eucalypti, Glycaspis brimblecombei and Spondyliaspis cf. plicatuloides. To determine host specificity, three Psyllaephagus species were collected locally from their hosts. Five-day-old parasitoids were exposed to all five developmental stages (I–V) of host and non-host psyllids in choice and non-choice tests. Similar bioassays were used to assess parasitoid preferences for specific nymphal stages, identifying their preferred developmental stages of potential hosts. Glycaspis brimblecombei was identified as a potential host for P. blastopsyllae, and S. cf. plicatuloides as an alternate host for P. bliteus, though emergence rates were three to four times lower than for their known hosts. Psyllaephagus pilosus showed no interest in non-host psyllids. Female parasitoids displayed stage-specific preferences for both known and newly identified hosts. The current findings indicate that some Psyllaephagus species attack hosts within an ecological niche, whereas others are highly host specific. Additionally, the distinction between potential host range observed in laboratory conditions and ecological host range in field conditions should be considered, as laboratory tests typically exhibit a broader host range.
Pheromonal variation and mating between two mitotypes of fall armyworm (Spodoptera frugiperda) in Africa
(Nature Research, 2024) Sisay, Birhanu; Tamiru, Amanuel; Subramanian, Sevgan; Weldon, Christopher William; Khamis, Fathiya; Green, Kristina Karlsson; Anderson, Peter; Torto, Baldwyn
In the Americas, the fall armyworm (Spodoptera frugiperda) exists in two genetically distinct strains, the corn (C) and rice (R) strains. Despite their names, these strains are not associated with host plant preferences but have been shown to vary in pheromone composition and male responses. Recently, S. frugiperda was detected in Africa as an invasive species, but knowledge about variation in strain types, pheromone composition and inter-strain mating of populations of the pest in the continent has not been fully examined. Therefore, this study aimed to investigate variations, if any in the pheromone composition of female moths, male moth responses, and mating between C and R mitotypes of S. frugiperda populations in Kenya, as well as their geographic distribution. Strains (mitotypes) of S. frugiperda were identified using mitochondrial DNA (mtDNA) markers, and their pheromonal composition determined by coupled gas chromatography-mass spectrometric (GC-MS) analysis. Male moth responses to these compounds were evaluated using GC-electroantennographic detection (EAD), electroantennogram (EAG), and wind tunnel assays. Oviposition assays were used to determine whether R and C mitotype moths could mate and produce eggs. The results showed that both the R and C mitotypes were present, and there were no statistically significant differences in their distribution across all sampled locations. Five pheromone compounds including (Z)-7-dodecenyl acetate (Z7-12:OAc), (Z)-7-tetradecenyl acetate (Z7-14:OAc), (Z)-9-tetradecenyl acetate (Z9-14:OAc), (Z)-11-tetradecenyl acetate (Z11-14:OAc) and (Z)-11-hexadecenyl acetate (Z11-16:OAc), were detected in the pheromone glands of female moths of both mitotypes, with Z9-14:OAc being the most abundant. The relative percentage composition of Z9-14:OAc was similar in both mitotypes. However, the R mitotype had a 2.7 times higher relative percentage composition of Z7-12:OAc compared to the C mitotype moth, while the C mitotype moth had a 2.4 times higher relative percentage composition of Z11-16:OAc than the R mitotype moth. Male moths of both mitotypes exhibited similar responses to the pheromone compounds, showing the strongest responses to Z9-14:OAc and Z7-12:OAc in electrophysiological and behavioural assays. There was mating between R and C mitotypes with egg production comparable to mating within the same mitotype. Our results revealed that differences between the two S. frugiperda mitotypes are characterized by female moth pheromone composition rather than male moth responses to the pheromones, and that this does not prevent hybridisation between the mitotypes, which may have implications for their management.
The slow pandemic : emergence of antimicrobial resistance in the postadvent of SARS-CoV-2 pandemic
(Wiley, 2025-04) Osunla, Ayodeji; Oloye, Femi; Kayode, Adeoye John; Femi-Oloye, Oluwabunmi; Okiti, Ayomide; Servos, Mark; Giesy, John
BACKGROUND : The unprecedented outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has dramatically changed the global approach to public health, emphasizing the importance of measures to control and prevent infections. In response to the COVID-19 crisis, stringent hygiene practices and surface disinfection have become the norm, with an unprecedented surge in the use of disinfectants and antiseptics (DAs). MAIN TEXT : While these measures have been crucial in curbing the spread of the virus, an emerging concern has taken center stage: the potential impact of the prolonged and widespread use of antimicrobial compounds in these products on the development of antibiotic resistance. Antimicrobial resistance (AMR) has long been recognized as one of the most pressing global health threats. Quaternary ammonium compounds (QAC) such as benzalkonium chloride, benzethonium chloride, and cetylpyridinium chloride, which are extensively used in DAs formulations, have gained less attention in the context of AMR. CONCLUSION : A high abundance of QACs was detected in wastewater, and certain bacteria such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterococcus species developed resistance to these compounds over time. We analyzed the available evidence from the scientific literature, examining the presence and concentrations of QACs in different water sources, and their resistance mechanisms. This review aimed to shed light on the multifaceted challenges that arise from the dual battle against the COVID-19 pandemic and the ongoing global fight against AMR.
Uncovering cryptic species diversity of Ophiocordyceps (Ophiocordycipitaceae) associated with Coleoptera from Thailand
(Westerdijk Fungal Biodiversity Institute, 2024-12) Mongkolsamrit, S.; Noisripoom, W.; Tasanathai, K.; Khonsanit, A.; Thanakitpipattana, D.; Lamlertthon, S.; Himaman, W.; Crous, Pedro W.; Stadler, M.; Luangsa-ard, J.J.
This study advances our understanding of Ophiocordyceps, an extensively studied entomopathogenic fungus within the Ophiocordycipitaceae, particularly in Thailand. We introduce seven novel species associated with Coleoptera - O. albostroma, O. brunnea, O. capilliformis, O. kohchangensis, O. phitsanulokensis, O. pseudovariabilis, and O. ratchaburiensis. Remarkably, O. brunnea, O. kohchangensis, and O. ratchaburiensis exhibit ascomata on the subterminal region of the stromata, with the asexual form appearing at the apex of the stipe, reminiscent of O. brunneipunctata. In contrast, O. phitsanulokensis produces its ascomata in the upper region of the stipe. Shared traits include immersed perithecia and part-spores production. Ophiocordyceps albostroma and O. pseudovariabilis produce pseudo-immersed perithecia, with the former producing ascospores breaking into four part-spores, and the latter displaying 32 part-spores. Ophiocordyceps capilliformis is also introduced due to morphological distinctions from closely related species. Phylogenetic analyses based on multigene loci (LSU, TEF1, RPB1, RPB2) robustly confirm the placement of these new species within Ophiocordyceps. Additionally, we report a new record of O. clavata in Thailand.

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