Research Articles (Plant Production and Soil Science)
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Item Two new endemic species of Hermannia L. (Malvaceae: Byttnerioideae)-H. lilacina and H. boschbergensis-from the Cape Midlands Escarpment (Eastern Cape, South Africa)Clark, V. Ralph; Vidal Jr, Joao De Deus; Gwynne-Evans, David; Barker, Nigel (Elsevier, 2026-03)Hermannia L. is primarily an African genus of some 250 species, with the centre of diversity located in southern Africa. It is the sixth-most endemic-rich genus in the Greater Cape Floristic Region, although endemics occur in all biomes in southern Africa. Two new species of Hermannia L. (Malvaceae: Byttnerioideae) are described from the Cape Midlands Escarpment mountains, Eastern Cape Province of South Africa. Hermannia lilacina Gwynn. & V.R.Clark is common in Karoo Escarpment Grassland (Grassland Biome), mostly above 1600 m in the eastern Sneeuberg Massif (Nardousberg to Aasvoëlkrans, i.e. behind Graaff-Reinet to Pearston), with one record from the interior of the western Great Winterberg–Amatholes (i.e. near Tarkastad). Hermannia boschbergensis Gwynn. & V.R.Clark is apparently confined to mid-elevations in Eastern Cape Escarpment Thicket (Albany Thicket Biome) at 1200 m on the Boschberg (eastern Sneeuberg, near KwaNajoli/Somerset East) and is currently only known from two collections. Recognition of these two new species complements numerous other recent discoveries from these mountains. HIGHLIGHTS • Two new species of Hermannia are described from the Eastern Cape, South Africa. • Hermannia lilacina is endemic to the Sneeuberg and Great Winterberg–Amatholes. • Hermannia boschbergensis is endemic to the Boschberg (Sneeuberg). • Eastern Cape endemic Hermannia are doubled from two to four taxa.Item Intra-island variation in wind patterns on sub-Antarctic Marion IslandSchoombie, Janine; Craig, K.J. (Kenneth); Goddard, Kyle Andrew; Hedding, D.W. (David William); Nel, W.; Le Roux, Peter Christiaan (University of Pretoria, 2025-10)Sub-Antarctic Marion Island provides a critical habitat for pelagic species, yet its terrestrial ecosystem faces increasing threats from climate change. Despite being situated in one of the windiest regions globally, the impact of changing wind patterns at the intra-island scale remains poorly understood. Existing datasets lack the spatial resolution necessary to capture fine-scale wind dynamics across the island. This study aimed to address this gap by presenting high-resolution wind speed and direction data to investigate the effects of wind on terrestrial systems. We present two complementary datasets: (1) wind measurements collected from 17 stations distributed across the island between May 2018 and March 2021, and (2) computational fluid dynamics (CFD) simulations providing wind vectors and associated properties at a 30 × 30 m resolution for heights up to 200 m above ground level. The data reveal significant differences in wind speed and direction across different geographical sectors of Marion Island. Notably, anemometers situated in the south recorded more frequent gale-force winds, while the western stations experienced calmer conditions. By using the observed wind direction frequencies, a weighted average vector plot was generated from the CFD simulations, providing an island-scale representation of spatial wind patterns across the island. These datasets offer valuable insights into variations in wind patterns, including upstream and downstream effects, and serve as a crucial resource for studying wind-driven processes affecting the landscape and ecosystem, such as seed dispersal.Item Plant trait matching occurs in facilitative interactions across global drylandsSmit, Imke C.; Le Roux, Peter Christiaan; Soliveres, Santiago; Gross, Nicolas; Le Bagousse-Pinguet, Yoann; Saiz, Hugo; Abedi, Mehdi; Ahumada, Rodrigo; Arroyo, Antonio I.; Asensio, Sergio; Benoit, Richard; Blaum, Niels; Bu, Chongfeng; Eldridge, David; Fajardo, Alex; Farzam, Mohammad; Fateh, Amghar; García-Gómez, Miguel; Gaitán, Juan J.; Gonzalez, Sofia; Gozalo, Beatriz; Greenville, Aaron C.; Guirado, Emilio; Hering, Robert; Leder, Cintia V.; Li, Xinhao; Liu, Jushan; Louw, Michelle Anne; Manzaneda, Antonio J.; Marais, Eugene; Martínez-Valderrama, Jaime; Mendoza, Betty J.; Mora, Juan P.; Moreno, Gerardo; Ochoa, Victoria; Oñatibia, Gastón R.; Peter, Guadalupe; Pueyo, Yolanda; Quiroga, Emiliano; Rahmanian, Soroor; Rey, Pedro J.; Rolo, Victor; Plaza, César; Sarig, Shlomo; Selyari, Javad; Travers, Samantha; Valencia, Enrique; Wang, Deli; Wang, Lixin; Wardle, Glenda; Yahdjian, Laura; Zaady, Eli; Zhang, Yuanming; Zhou, Xiaobing; Maestre, Fernando T. (Wiley, 2025)AIM : Plant functional traits can influence interaction outcomes between nurse and target plants through a “functional trait match”, which occurs when the traits of nurse plants ameliorate their environment, and target plants possess traits that allow them to benefit from this ameliorated environment. We investigated how the traits of putative nurse species affect interaction outcomes across global drylands and determined the functional match that promotes facilitation. We also investigated how grazing pressure and global climatic and edaphic gradients affected this trait match. LOCATION : Global drylands. TIME PERIOD : 2016–2019. MAJOR TAXA STUDIED : Vascular plants. METHODS : We used a collaborative survey conducted across 29 sites from five continents, where we gathered in situ co-occurrences of dominant species (‘nurses’) and other vascular plant species, as well as their functional traits [plant height and leaf dry matter content (LDMC)]. Climate, edaphic variables and grazing pressure were measured in situ or extracted from databases. We used a model building approach to determine the effect of dominant plant traits on interaction outcomes, and how the functional trait match between nurse and target species is affected by environmental variables. RESULTS : Tall dominant plants with conservative leaves generally had a greater positive effect on species richness and cover beneath their canopies, but these effects were strongly modulated by grazing pressure and soil pH. Target plants that were significantly associated with dominant plants tended to be shorter, and have more acquisitive leaves than dominant plants, regardless of environmental conditions. However, the difference in height and LDMC between dominant plants and negatively associated target plants was strongly affected by environmental conditions. MAIN CONCLUSIONS : Functional traits play a significant role in determining interaction outcomes between dryland plants. Facilitation in drylands is driven by a conservative-acquisitive trait match, a pattern observed regardless of grazing pressure, climate and soil conditions.Item Xenorhabdus innovationi sp. nov., associated with the entomopathogenic nematode Steinernema innovationi from South AfricaRitter, Carla L.; Wessels, Helene L.; Ramakuwela, Tshimangadzo; Hatting, Justin; Malan, Antionette P.; Dicks, Leon M.T. (Brill Academic Publishers, 2026-02)Please read abstract in the article.Item A latent invader : transcriptomics reveals Cercospora zeina's stealth infection strategy of maize and immune-activating effectorsNadasen, Trystan; Buitendag, Carla; Visser, Rode´; Welgemoed , Tanya; Hein, Ingo; Berger, David Kenneth (Frontiers Media, 2025-11-07)Cercospora zeina is a fungal pathogen that causes gray leaf spot (GLS) disease on maize (Zea mays L.). Upon landing on a leaf, the pathogen enters through the stomata and continues to develop asymptomatically for up to 28 days before symptoms appear. As previous work has yet to adequately determine how the pathogen behaves during its infective period, we used transcriptomics to gain insights about the in-planta development of the pathogen and explore its use of effectors to facilitate this process. Samples from B73 maize inbreds inoculated with an African reference strain of C. zeina (CMW25467) were harvested in a time course experiment and used for deep RNA sequencing. We used reads mapped to an improved assembly and annotation of the C. zeina CMW25467 genome as a proxy for biomass accumulation. Following the latent period, C. zeina was found to rapidly accumulate biomass and showed a nearly 50-fold increase in biomass as symptoms appeared. Two distinct transcriptional waves occurred across the infection period. The first wave showed expression of genes for cellular growth, maintenance and immune avoidance, whereas the second wave was enriched with genes involved in detoxification and carbohydrate catabolism. A total of 140 putative effector genes were differentially expressed over the time course, with most upregulated during the mid stage when the switch to necrotrophy occurred. Transient expression of three of these C. zeina effectors (CzEcp2, CzNIS1a, CzNIS1b) induced plant immunity in Nicotiana spp. resulting in the development of cell death. The CzNIS1a effector required a signal peptide for activity in Nicotiana benthamiana, indicating that it is most likely secreted into the apoplast for this function. The previously undescribed CzNIS1b family member has an N-terminal domain with high sequence and structural identity to CzNIS1a plus a C-terminal domain made up of four alpha helices. Orthologues of CzNIS1b appear to be limited to the Mycosphaerellaceae. This study suggests that a cohort of C. zeina effectors expressed during the mid-stage of infection have functions for which receptors are present in non-host species like tobacco. Altogether, this work suggests C. zeina behaves as a latent necrotroph and provides a foundation for future research into the infection biology of C. zeina.Item Enhancing multi-season wheat yield through plant growth-promoting rhizobacteria using consortium and individual isolate applicationsBreedt, Gerhardus; Korsten, Lise; Gokul, Jarishma Keriuscia (Springer, 2025-12)In recent decades, there has been a growing interest in harnessing plant growth-promoting rhizobacteria (PGPR) as a possible mechanism to mitigate the environmental impact of conventional agricultural practices and promote sustainable agricultural production. This study investigated the transferability of promising PGPR research from maize to another Poaceae cereal crop, wheat. This multi-seasonal study evaluated the wheat grain yield effect of Lysinibacillus sphaericus (T19), Paenibacillus alvei (T29) when applied i. individually, ii. as a consortium with Bacillus safensis (S7), and iii. at a 75% reduced fertilizer rate. Whole genome sequencing allowed annotation of genes linked to plant growth promotion, providing potential genomic explanations for the observed in-field findings. Application of the consortium compared to a commercial PGPR showed significantly increased wheat yield by 30.71%, and 25.03%, respectively, in season one, and 63.92% and 58.45%, respectively, under reduced fertilizer rates in season two. Individual application of T19 and T29 showed varying results, with T19 increasing wheat yield by 9.33% and 16.22% during seasons three and four but a substantial reduction (33.39%) during season five. T29 exhibited yield increases during season three (9.31%) and five (5.61%) but led to a significant reduction (21.15%) in season four. Genomic analysis unveiled a spectrum of plant growth-promoting genes including those associated with ammonification, phosphate solubilization, ethylene, siderophore, catalase, and superoxide dismutase production. These findings offer valuable insights into the mechanisms behind observed field results, with potential implications for advancing sustainable agriculture and crop productivity in evolving agricultural landscapes.Item Safeguarding microbial biodiversity : microbial conservation specialist group within the species survival commission of the International Union for conservation of natureGilbert, Jack A.; Scholz, Amber Hartman; Bello, Maria Gloria Dominguez; Korsten, Lise; Berg, Gabriele; Singh, Brajesh K.; Boetius, Antje; Wang, Fengping; Greening, Chris; Wrighton, Kelly; Bordenstein, Seth R.; Jansson, Janet; Lennon, Jay T.; Souza, Valeria; Allard, Sarah M.; Thomas, Torsten; Cowan, Don A.; Crowther, Thomas W.; Nguyen, Nguyen; Harper, Lucy; Haraoui, Louis-Patrick; Ishaq, Suzanne L.; McFall-Ngai, Margaret; Redford, Kent H.; Peixoto, Raquel (Oxford University Press, 2025-01)No abstract available.Item Occurrence, concentration, and risk assessment of selected pharmaceuticals in representative cropland soils and their underlying groundwater in Gauteng province, South AfricaNgoetjana, Matome Peter; Tesfamariam, Eyob Habte; Brown, Sally; Wooding, Madelien; Dippenaar, Matthys Alois (Springer, 2025-08)Traceable levels of pharmaceuticals are frequently detected in various environmental matrices. However, studies investigating the occurrence of pharmaceuticals in cropland soils and underlying groundwaters are relatively limited, hindering risk assessments. This study aims the following: (1) determine the occurrence of selected pharmaceuticals in cropland soils and underlying groundwater, (2) investigate the correlations between pharmaceutical’s occurrence in cropland soils and underlying groundwater, (3) evaluate the correlations between soil and water parameters and pharmaceutical’s concentration, and (4) estimate human health risk from pharmaceuticals present in groundwater. A single soil and groundwater sampling campaign was conducted across eighteen farmers’ fields, characterized by varying farm management practices. Caffeine, carbamazepine-10,11-epoxide, carbamazepine diol, and N4-acetylsulfamethoxazole were detected in groundwater, with concentrations reaching 67.1, 106.7, 506.7, and 113.8 ng L−1, respectively. Three of these compounds, carbamazepine-10,11-epoxide, carbamazepine diol, and N4-acetylsulfamethoxazole, were also present in soils with concentrations reaching 10.0, 353.5, and 59.1 ng g−1 dry weight, respectively, indicating potential soil-to-groundwater transfer. Principal component analysis revealed a strong correlation between the application of commercial inorganic fertilizers and carbamazepine-10,11-epoxide levels and the irrigation practices and the levels of caffeine, carbamazepine diol, and N4-acetylsulfamethoxazole in the soil and groundwater. Risk quotients showed that caffeine poses negligible risk to human health through drinking water exposure. Overall, the findings suggest that pharmaceuticals are present in South African croplands and underlying groundwater, though current levels do not pose a significant risk to human health. However, future studies should focus on other metabolites of pharmaceuticals due to their higher concentrations in the soil and groundwater.Item Exploring household forest dependency : socio-economic drivers, resource utilisation, and conservation challenges in eastern CameroonEbanga, André Paul; Zekeng, Jules Christian; Chimi, Cédric D.; Fobane, Jean Louis; Etoundi Menyene, Laurent Florent; Syampungani, Stephen; Mbolo, Marguérite Marie (Elsevier, 2026-06)Tropical forests play a vital role in sustaining rural livelihoods while providing essential ecosystem services at global, regional, and local scales. However, increasing human pressure and changing socio-economic dynamics threaten the balance between conservation goals and community subsistence needs. In tropical regions, household dependence on forest resources is influenced by complex socioeconomic and demographic factors. This study, conducted in 10 villages adjacent to the Angossas Community Forest (ACF) in eastern Cameroon, assessed how socioeconomic and demographic factors shape forest dependence and local sustainability strategies. Using stratified random sampling, 223 households were surveyed using semi-structured questionnaires, which captured demographic, cultural, and socio-economic variables through both closed- and open-ended recall questions. The methodology integrated descriptive statistics, non-parametric tests (Kruskal-Wallis), binary logistic regressions, and interdependence tests. The Dependency Index (EDI) was estimated at 0.15, indicating that 78.38% of households were dependent on forest resources. Dependence levels varied significantly across forest product categories (p < 0.05), particularly for timber (15.42%), traditional medicine (16.14%), food (14.22%), cultural practices (13.98%), and handicrafts (12.53%). Regression analysis revealed that education level significantly influenced subsistence use (β = -0.165; p = 0.015) and medicinal plant collection (β = 1.605; p = 0.030). Gender (β = 1.860; p = 0.001) and age (β = 0.624; p = 0.028) were identified as key determinants for timber extraction and agricultural practices. Tree felling was the most prevalent activity (64.04%), while 82.09% of the population engaged in slash-and-burn agriculture. Intensive exploitation affected 41.75% of resources, resulting in species depletion. Our study findings highlight the need to integrate socio-economic factors into forest management policies. Community-based strategies should be strengthened with targeted support and rigorous monitoring to ensure sustainable use of forest resources while safeguarding rural livelihoods.Item Identification of sources of Fusarium head blight and deoxynivalenol resistance in Ethiopian wheat cultivarsMawcha, Kahsay Tadesse; Yang, Wenxiang; Ndolo, Dennis (Springer, 2026-02)Fusarium head blight (FHB), caused by Fusarium graminearum, poses a significant threat to wheat production in Ethiopia, causing yield losses of up to 30–70% in severe epidemics and contaminating grain with deoxynivalenol (DON). This study aimed to identify sources of FHB and DON toxin resistance among selected Ethiopian wheat cultivars. Forty-three cultivars were evaluated for FHB resistance under greenhouse and field conditions, using the spawn inoculation method. Disease index (DI), Fusarium-damaged kernels (FDK), and DON content were quantified. The mean DI across cultivars ranged from 2.33% to 56.8%, FDK from 1.2% to 48.5%, and DON from 0.12 to 8.64 mg kg⁻¹. Cultivar “Sulla” exhibited the highest level of FHB resistance with a stable DI of 2.33%, FDK of 1.8%, and DON content of 0.16 mg kg⁻¹—the first such finding reported in Ethiopian germplasm. Notably, cultivars “Menze”, “Shorima”, and “Lemu” displayed strong resistance to DON contamination, with toxin levels ≤ 0.25 mg kg⁻¹, exceeding previously reported resistance thresholds. Eleven cultivars, including “Sulla”, exhibited significantly reduced yield losses (< 10%) compared to controls, whereas cultivars such as “Abola”, “Alidoro”, “Kakaba”, “Kingbird”, and “Simba” accumulated the highest DON levels (≥ 6.5 mg kg⁻¹) and showed high susceptibility. Based on the specific molecular marker Xumn10, the Fhb1 resistance gene was detected in 23 cultivars and the resistant control, “Sumai-3”. These findings significantly expand the pool of resources for FHB and DON resistance in Ethiopian wheat breeding, with the potential to improve yields by up to 20% and reduce mycotoxin contamination by more than 80% in FHB hotspots.Item Launching the IUCN Microbial Conservation Specialist Group as a global safeguard for microbial biodiversityGilbert, Jack A.; Peixoto, Raquel S.; Scholz, Amber Hartman; Dominguez Bello, Maria Gloria; Korsten, Lise; Berg, Gabriele; Singh, Brajesh; Boetius, Antje; Wang, Fengping; Greening, Chris; Wrighton, Kelly; Bordenstein, Seth; Jansson, Janet K.; Lennon, Jay T.; Souza, Valeria; Thomas, Torsten; Cowan, Don A.; Crowther, Thomas W.; Nguyen, Nguyen; Harper, Lucy; Haraoui, Louis-Patrick; Ishaq, Suzanne L.; Redford, Kent (Nature Research, 2025-10)Despite its importance, microbial life is largely absent from global conservation frameworks. Launched in July 2025, the Microbial Conservation Specialist Group (MCSG) was established as a Species Survival Commission (SSC) by the International Union for Conservation of Nature (IUCN). The IUCN is the world’s leading authority in environmental science and policy, renowned for shaping conservation priorities across governments, non-governmental organizations and international treaties. The MCSG convenes a coalition of microbiologists, ecologists, traditional knowledge experts and conservation leaders to develop and advocate for conservation tools, strategies and policies that explicitly integrate microbiology into global biodiversity governance. Despite the importance of microorganisms for ecosystem function, their role has been seen as too abstract or complex to integrate into policy. Elevating microbial perspectives within global conservation has required overcoming a deep-rooted tendency to overlook the invisible.Item Ten practical guidelines for microclimate research in terrestrial ecosystemsDe Frenne, Pieter; Beugnon, Rémy; Klinges, David; Lenoir, Jonathan; Niittynen, Pekka; Pincebourde, Sylvain; Senior, Rebecca A.; Aalto, Juha; Chytrý, Kryštof; Gillingham, Phillipa K.; Greiser, Caroline; Gril, Eva; Haesen, Stef; Kearney, Michael; Kopecký, Martin; Le Roux, Peter Christiaan; Luoto, Miska; Maclean, Ilya; Man, Matěj; Penczykowski, Rachel; Van den Brink, Liesbeth; Van de Vondel, Stijn; De Pauw, Karen; Lembrechts, Jonas J.; Kemppinen, Julia; Van Meerbeek, Koenraad (Wiley, 2025-02)1. Most biodiversity dynamics and ecosystem processes on land take place in microclimates that are decoupled from the climate as measured by standardised weather stations in open, unshaded locations. As a result, microclimate monitoring is increasingly being integrated in many studies in ecology and evolution. 2. Overviews of the protocols and measurement methods related to micro climate are needed, especially for those starting in the field and to achieve more generality and standardisation in microclimate studies. 3. Here, we present 10 practical guidelines for ground-based research of terrestrial microclimates, covering methods and best practices from initial conceptualisation of the study to data analyses. 4. Our guidelines encompass the significance of microclimates; the specifics of what, where, when and how to measure them; the design of microclimate studies; and the optimal approaches for analysing and sharing data for future use and collaborations. The paper is structured as a chronological guide, leading the reader through each step necessary to conduct a comprehensive microclimate study. At the end, we also discuss further research avenues and development in this field. 5. With these 10 guidelines for microclimate monitoring, we hope to stimulate and advance microclimate research in ecology and evolution, especially under the pressing need to account for buffering or amplifying abilities of contrasting microhabitats in the context of global climate change.Item Lessons learned from compiling a flora checklist for the Cape Peninsula, South AfricaRebelo, Anthony G.; Holmes, Patricia M.; Spear, Dian; Klopper, Ronell Renett; Van Wilgen, Nicola J. (AOSIS, 2025-11-30)Checklists form an important component of biodiversity conservation, underpinning species monitoring, conservation planning and management prioritisation. Developing an accurate and taxonomically up-to-date plant checklist for a protected area requires the integration of diverse datasets, verification of species names and careful data management. Using the Cape Peninsula, South Africa, as a case study, we outline key steps and considerations in curating a comprehensive checklist for protected area management. We compiled data from multiple sources, including herbaria, museum collections, local conservation agencies, non-governmental organisations, universities, private conservancies, historical surveys and citizen science platforms such as iNaturalist. Key recommendations for checklist development include: (1) defining the geographic and taxonomic scope of the checklist, (2) identifying data sources, (3) optimising database design with standardised data collection and essential metadata fields, (4) having a verifiable taxonomic backbone, and (5) a clear workflow for working through each data source. In this process, it is important to retain, but flag erroneous records rather than deleting them, make provision for correctly assigning status information to extralimital and alien species, and use a local taxonomic expert to assist in decision-making required for resolving errors. Challenges encountered during the compilation of the checklist include resolving taxonomic inconsistencies, handling misidentifications, addressing orthographical errors in plant names and filtering out cultivated records from naturally occurring species - particularly in iNaturalist data. Our methodology provides practical guidelines to minimise these challenges, aligning with international best practices for checklist compilation and maintenance. By ensuring data completeness, accuracy and taxonomic consistency, we offer a framework that can benefit future biodiversity monitoring and conservation efforts. CONSERVATION IMPLICATIONS : Accurate species checklists are crucial for informed conservation decisions. Standardised protocols for data validation and taxonomic accuracy enhance the reliability of biodiversity assessments, ultimately improving conservation outcomes in protected areas.Item A South African perspective on the 2023 IPBES Thematic Assessment Report on Invasive Alien Species and their controlWilson, John R.U.; Faulkner, Katelyn T.; Winzer, L. Fernandez; Mcculloch-Jones, E.J.; Van Wilgen, B.W.; Blanchard, R.; Carbutt, C.; Dechoum, M.S.; Foxfroft, L.C.; Greve, Michelle; Hui, C.; Ivey, P.; Kgope, B.; Kumschick, S.; Le Roux, Peter Christiaan; Masehela, T.S.; Measey, J.; Miza, S.; Mogapi, T.; Mpikanisi, F.; Mulaudzi, L.; Nelukalo, K.; Nnzeru, L.; Nsikani, M.M.; Pattison, Z.; Rahlao, S.J.; Richardson, D.M.; Robinson, T.B.; Shackleton, R.T.; Tererai, F.; Tshidada, N.; Tshikhudo, P.P.; Tshivhandekano, I.; Wanjau, K.; Ziller, S.R.; Zengeya, Tsungai Alfred (South African National Biodiversity Institute, 2025-11-06)BACKGROUND : Biological invasions are a major threat to biodiversity and sustainable development. A global assessment of biological invasions released in 2023 by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), concluded that while invasions ‘…cause dramatic and, in some cases, irreversible changes…’ they can be ‘…overcome through a context-specific integrated governance approach’. AIM : Here we evaluate insights from the IPBES assessment in the context of South Africa and explore how these insights could inform the development of a national policy and strategy to address biological invasions. RESULTS : Trends and status of biological invasions in South Africa are similar to those seen globally, but there are some distinct local nuances. South Africa has: 1) a long history of invasions with negative impacts caused especially by invasive trees and freshwater fishes, whilst invasive marine invertebrates have transformed large parts of the coastline; 2) a long history of control (biological control was first implemented in 1913) with large-scale, state-run invasive species management programmes currently in place; 3) a comprehensive regulatory system (e.g., there is provision for beneficial invasive species to be used under permits); 4) relatively high levels of awareness and engagement (at least among some stakeholder groups); and 5) a well-connected community of practice. DISCUSSION : Efforts to limit introductions (intentional or unintentional) are difficult given South Africa’s extensive and porous borders and the pressing need to increase trade and travel. Regulatory and implementation efforts aimed at prevention are improving, with the newly established Border Management Authority aiming to integrate biosecurity interventions at ports of entry. Such integrated governance is, we argue, needed more broadly if affected sectors, society groups and stakeholders are to be effectively included in decision-making and management. A more systematic flow of information from observation to action is essential, as is better feedback between research, policy and implementation at all scales. Biological invasions will continue to pose threats, but many of these can be effectively mitigated through focussed interventions. Co-ordinating such interventions in the context of other cross-cutting global change challenges and initiatives is a cost-effective way of protecting and improving livelihoods, human health, quality of life and biodiversity.Item Climate change and the antinutrient–antioxidant puzzle in common bean seedsVorster, Juan; Cominelli, Eleonora; Sparvoli, Francesca; Losa, Alessia; Sala, Tea; Kunert, Karl J. (Wiley, 2026-02)Non-proteinaceous and proteinaceous antinutrients in common bean (Phaseolus vulgaris L.) seeds can negatively affect human nutrition by reducing mineral bioavailability and impairing protein digestibility during digestion, respectively. However, many of these compounds also possess strong antioxidant properties that can help protect the plant from oxidative stress. While strategies to reduce antinutrient levels have been proposed to enhance the nutritional value of beans, less attention has been given to their potential protective functions, particularly under abiotic stress conditions. In the context of ongoing global climate change - marked by more frequent and prolonged drought and heat stress - there is a significant research gap concerning the influence of these environmental stresses on the accumulation and function of seed antinutrients in common beans. This perspective paper reviews current knowledge on the production of antioxidative antinutrients in response to abiotic stress and highlights the dual role of these compounds. It also outlines key research directions needed to better understand how climate-induced stress may alter antinutrient levels, and the implications this may have for both human nutrition and plant resilience. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.Item Multiple large and small-spored Alternaria species causing leaf spot of potato in South AfricaCruywagen, Elsie M.; Sutherland, Rene; Nkosi, Brightness Z.; Van der Waals, Jacqueline Elise; Truter, Mariette (Springer, 2026)Early blight and brown spot of potato in South Africa are caused by Alternaria solani and A. alternata, respectively. However, elsewhere in the world, other Alternaria species have also been associated with leaf spot of potato. These species include A. grandis, A. protenta, A. arborescens, A. cantlous, A. infectoria and A. dumosa. Potato growing regions in South Africa were surveyed to determine which Alternaria species cause disease on potato. Samples were collected from September 2018 to April 2021 from 13 potato production regions in South Africa. Alternaria isolates obtained from collected samples were identified based on morphology and phylogenetic analyses of Alt a 1, tef 1-α, gapdh and rpb2 gene regions, depending on the morphological group the isolates were placed into. In addition to A. alternata and A. solani, two additional species were identified based on sequencing results, namely A. arborescens species complex (SC) and A. grandis. Virulent isolates were selected based on a detached leaf assay and inoculated onto potato plants in the greenhouse. Symptoms similar to those observed in the field were observed and the pathogens reisolated and identified. Alternaria grandis isolates caused symptoms similar to those of A. solani (early blight) and A. arborescens SC caused symptoms similar to those of A. alternata (brown spot). This is the first report of A. grandis and A. arborescens SC causing leaf spot of potato in South Africa.Item Yield and quality characteristics of maize-forage legume mixtures cultivated under different tillage systemsMosebi, Poloko Emmanuel; Madakadze, Ignacio Casper; Ntakatsane, M.P.; Ratsele, R. (University of Zagreb, Faculty of Agriculture, 2025)Planted forage grown under an appropriate cropping system and tillage practice can help to improve yield potential. This study was conducted to evaluate the effects of different tillage practices on the growth, nutrient composition and yield characteristics of maize-forage legume mixtures. Different forage types were represented by sole maize (Zea mays L.), sole common vetch (Vicia sativa L.), sole lablab (Lablab purpureus), maize + common vetch, and maize + lablab intercrops. Forage types were cultivated under different tillage systems, viz., conventional tillage (CT), deep ploughing with a depth of 30 cm, and reduced tillage (RT), shallow ploughing with a depth of 10 cm. Forage samples were collected to examine the growth indices, chemical composition and yield components. Reduced tillage showed lower values of crop growth rate, leaf area, and leaf area index (11.68 g/m2/d, 3.30 m2, and 4.09 m2/m2, respectively) in sole forages than conventional tillage. Higher dry matter production (35.66%) in forage intercrops and higher values of crude protein content (20.16% DM) in sole forage legumes were observed in the conventional tillage practice than in the reduced t illage practice. Fiber concentrations of sole forages were greatest in reduced tillage and lowest in conventional tillage practices. Higher values of total dry matter and grain yield, harvest index and plant density in forage mixtures were obtained in the conventional tillage than in the reduced tillage. The study concluded that growing sole forages and mixtures under different tillage systems can influence yield and nutritional characteristics.Item Large herbivores are linked to higher herbaceous plant diversity and functional redundancy across spatial scalesTrepel, Jonas; Atkinson, Joe; Le Roux, Elizabeth; Abraham, Andrew J.; Aucamp, Margerie; Greve, Michelle; Greyling, Marilize; Kalwij, Jesse M.; Khosa, Steven; Lindenthal, Lukas; Makofane, Caroline; Mokoena, Londiwe; Oosthuizen, Anika; Rech, Bent J.; Lundgren, Erick; Svenning, Jens-Christian; Buitenwerf, Robert (Wiley, 2026-01)Large herbivores can strongly influence plant communities. However, these effects are highly variable, potentially depending on the herbivore regime, that is, herbivore diversity and density. However, the role of the herbivore regime has been challenging to evaluate across spatial scales due to widespread defaunation and a lack of data on herbivore communities and their densities. Here, we investigated the effects of large herbivores along a gradient of trophic complexity (low to high herbivore diversity) and herbivory intensity (estimated from herbivore biomass and visitation frequency) on plant taxonomic and functional diversity at different scales (plot [n = 250], site [n = 50] and landscape [n = 10]) in 10 reserves in the savanna biome in South Africa. We found higher total plant species richness, driven by higher herbaceous (but not woody) plant species richness, in areas with higher herbivory intensity across multiple scales. While herbivores had no significant relationship with plant functional richness, we observed higher functional redundancy at all scales in areas more frequently visited by herbivores. Overall, herbivore–vegetation relationships were largely consistent across scales, and the strongest effects emerged at the largest scale. Our results show a positive relationship between large herbivores and both herbaceous plant species richness and plant functional redundancy, the latter suggesting higher vegetation resilience (the capacity of ecosystems to quickly recover from disturbances as different species compensate for the loss or decline of others). These effects are largely consistent across scales, indicating that the impact of herbivore regimes on plant communities is predominantly scale-independent and that large herbivores drive vegetation dynamics at both local and large scales. However, the stronger effects observed at the landscape scale imply that herbivore impacts manifest most prominently at larger scales. Altogether, our results suggest that restoring large herbivore populations can be expected to promote herbaceous plant diversity and ecosystem resilience.Item Gunnera perpensa L. - mediated gold nanoparticles with enhanced anti-gonococcal activityDembetembe, Tanyaradzwa Tiandra; Twilley, Danielle; Maphutha, Jacqueline; De Canha, Marco Nuno; Thipe, Velaphi Clement; Mandiwana, Vusani; Kalombo, Lonji; Rikhotso, Rirhandzu S.; Ray, Suprakas Sinha; Lall, Namrita; Kritzinger, Quenton (Elsevier, 2026-03)Gonorrhoea is the second most prevalent sexually transmitted disease (STD) worldwide, with its treatment increasingly compromised by antibiotic resistance to available treatments. This has led to the investigation of bioactive plants as sources for novel drug development, with plant-based nanoparticles showing promise in treating STDs. This study aimed to evaluate the anti-gonococcal activity and cytotoxicity of the ethanolic root extract of Gunnera perpensa L. (GP) and to determine whether synthesis of gold nanoparticles (AuNPs) from GP showed enhanced biological activity. Characterization of the nanoparticles was performed using ultraviolet–visible spectrometry (UV–Vis), transmission electron microscopy (TEM), dynamic light scattering (DLS), Zeta potential, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Lastly, the anti-gonococcal activity and cytotoxicity of GP and GP-AuNPs were evaluated. The AuNPs exhibited a surface plasmon resonance at 536 nm, confirming the successful synthesis of nanoparticles, with a hydrodynamic size of 127.20 nm and a core size of 39.51 nm. The GP-AuNPs showed enhanced anti-gonococcal activity compared to GP with a minimum inhibitory concentration (MIC) of 10.40 and 46.70 μg/mL, respectively. Cytotoxicity was evaluated on human keratinocytes (HaCaT), human monocytes (THP-1), and STD-related human cervical adenocarcinoma (HeLa), with GP-AuNPs exhibiting fifty percent inhibitory concentrations (IC50) of 22.12 ± 0.52, 27.53 ± 6.02, and >38.96 μg/mL, respectively. In contrast, GP showed IC50 values > 400 μg/mL against all tested cell lines. These findings indicate that GP-AuNPs exhibit significant anti-gonococcal activity with greater selectivity for Neisseria gonorrhoeae over non-cancerous (HaCaT and THP-1) cells, as evidenced by selectivity indices (SIs) > 2. These findings suggest that both GP and GP-AuNP possess potential as lead candidates for the treatment of gonorrhoea. Their limited antiproliferative activity against HeLa cells (SI < 0.7) indicates they are unsuitable for treating STD-associated cervical cancers. To the best of our knowledge, no published studies have investigated the effect of plant-synthesized nanoparticles on their activity against N. gonorrhoeae; therefore, this is the first use of GP-AuNPs against N. gonorrhoeae, advancing plant-based nanomedicine for STDs. HIGHLIGHTS • First report on the anti-gonococcal activity and cytotoxicity of Gunnera perpensa gold nanoparticles (GP-AuNPs). • Significant anti-gonococcal activity (MIC = 10.40 μg/mL). • Significant selectivity (SI > 2) to the bacteria compared to non-cancerous (HaCaT and THP-1) cells.Item The potential of phytochemicals to overcome multidrug resistance in metastatic melanomaMaphutha, Jacqueline; Twilley, Danielle; Dawood, Mona; Efferth, Thomas; Lall, Namrita (Wiley, 2026-01)Metastatic melanoma is the most lethal form of skin cancer, accounting for most skin cancer-related deaths. Immunotherapies and targeted therapies have improved overall and progression-free survival rates in metastatic melanoma patients. The effectiveness of these therapies decreases due to multidrug resistance (MDR). In contrast to previous reviews, this review extensively highlights the hallmarks of MDR and strategies for reversal of MDR. The review also critically evaluates the challenges in clinical translation of phytochemicals for metastatic melanoma and strategies to overcome these challenges. This review also highlights the various gaps that exist in metastatic melanoma (e.g., vascularized organ-on-a-chip model has not been developed for melanoma which is largely influenced by angiogenesis). These gaps offer novel avenues that could be explored for clinical translation of phytochemicals.