Chepa shutki is a spontaneously fermented fish product appreciated for its rich flavour and widely consumed in Bangladesh. However, it is unknown how processing influences the flavour and microbial community. This study investigates the effects of processing variations on volatile organic compounds (VOCs) and bacterial communities in chepa shutki. 120 samples were collected cross-sectionally from different regions of Bangladesh, while recording fish type, district, fermentation time, container type, water activity and pH. Substantial variation in VOC profiles was observed, with phenols, pyrazines, alcohols, alkanes and acids as the predominant VOC groups. Most processing parameters were associated with one or more VOC groups, with fish type showing the strongest effect. Puma chepa shutki exhibited a higher VOC abundance, particularly pyrazines, whereas punti chepa shutki lacked phenols and showed higher levels of furanones. Tetragenococcus and Staphylococcus were detected in all samples, although overall bacterial community composition varied. Fish type and district significantly influenced bacterial communities, jointly explaining 13% of the variation. Limited correlation between bacterial communities and VOCs suggest functional redundancy among bacterial species. These findings highlight key processing parameters shaping functional properties of chepa shutki and inform future mechanistic studies to standardize traditional chepa shutki processing.

Summary The intensification of agriculture relies on chemical fungicides to manage crop disease 1,2 , leading to the evolution of resistance in plant pathogens. 3 Fungicides have long half-lives, allowing them to remain active well beyond their intended targets and affect downstream ecosystems and agricultural practices. The saprophytic fungus Aspergillus fumigatus is an airborne ubiquitous fungus and an important human pathogen causing severe life-threatening invasive fungal disease. 4 Selection pressure from agricultural triazoles, demethylase inhibitors (DMIs), has led to cross-resistance to clinical triazoles, as they share the same target gene, cyp 51A. 5,6 In the Netherlands 7,8 , most triazole resistance arises from two cyp 51A haplotypes, the TR 34 and TR 46 . 9,10 Genomic surveys of A. fumigatus have shown that these triazole-resistance alleles often co-occur with resistance alleles to non-DMI classes, these include some of the dominant fungicide classes used in Europe such as quinone outside inhibitors (QoIs), and succinate dehydrogenase inhibitors (SDHIs). 11 Hypothesizing that agricultural environments with non-DMI fungicides can indirectly select for triazole resistance, we used grass mesocosms to compete A. fumigatus isolates. We found that already at low concentrations, commonly found in agricultural residues, DMI, SDHI, and QoI fungicides can each independently increase the proportions of triazole resistant alleles. We show that the resistance alleles for each class are not intrinsically cross-resistant, indicating that their co-occurrences in allelic combinations produce this multi-resistance selection. Consistent with our mesocosms results, environmental samples contained high phenotypic (>20%) triazole resistance in heaps with only non-DMI fungicides. This work provides the first experimental and field evidence of selection for triazole resistance by non-triazole fungicides via genomic hitch-hiking. We thus predict that when novel fungicides are used in the same selective environment, novel resistance alleles will most likely be selected in isolates that have already accumulated resistance alleles to other fungicide classes. Because of linked resistance alleles, tackling selection and spread of environmental triazole resistance will require consideration of all fungicide classes. Graphical abstract Highlights Triazole-resistance alleles often co-occur with resistance alleles to non-DMI fungicide classes such as SDHI and QoI. DMI, SDHI, and QoI all independently increase the proportions of triazole resistant alleles at low concentrations (0.1 mg/kg) commonly found in agricultural residues. The DMI resistance allele TR 46 has a high fitness only under fungicide selective conditions, whereas TR 34 maintains its fitness also under fungicide free conditions. Beneficial alleles for one fungicide class increase in frequency and ‘hitch-hike’ with resistance alleles to other fungicide classes. Resistance alleles to novel fungicide classes will more likely be selected in isolates that already accumulated other fungicide resistance alleles.

Species sorting underlies changes in microbial community composition under varying environments, yet predicting the species diversity and their functional outcomes when exposed to novel conditions remains challenging. We explored this using mabisi, a Zambian traditional fermented milk, by propagating a shared starting mabisi microbial community across five novel substrates - raw bovine milk (control), low-fat milk, full-cream milk, and the infant formulas F100 and S26 – under static conditions and fixed dilution for 33 generations, at three rural farm sites. The microbial community composition was profiled through 16 S rDNA sequencing, and community-level functioning through volatile organic compounds, pH, and consistency. We observed a substrate-driven divergence of microbial communities, with low-fat milk enriched with Acetobacter, full-cream milk enriched with Lactococcus, and S26 enriched with Lactiplantibacillus and Leuconostoc. This pattern exhibited a temporal community succession but remained consistent between sites. Similarly, the community-level functionality diverged but remained largely repeatable to properties known for mabisi. Our findings suggest that novel environments drive a species sorting process in natural microbial communities, and this process persists over time. Additionally, the repeatability of its community-level functionality points to underlying functional redundancy within diverse and successive microbial communities. Our study not only advances the understanding of how microbial communities adapt to environmental changes but also provides a basis for harnessing the mabisi-derived microbial community for broad biotechnological applications, particularly supporting the feasibility and effectiveness of its use in an in-house formulated F100 infant formula for treating malnourished children in developing regions.

Abstract Rosa, belonging to the family Rosaceae, encompasses more than 150 species widely distributed across the northern hemisphere. Renowned for their beauty, roses are cultivated throughout the world for ornamental purposes and the production of essential oils and perfumes. Despite their cultural and commercial significance, the genomic resources of wild Rosa species have not been studied comprehensively, hampering the understanding of their genetic diversity, evolutionary history, and breeding potential. Here we present a Rosaceae panproteome and a Rosa pangenome, spanning wild, traditional garden, and modern rose lineages, constructed using a De Bruijn graph (DBG)-based approach, and introduce two high-quality de novo genomes for Rosa sericea and Rosa rugosa. A phylogeny of 18 Rosa haplotypes based on 4367 single-copy core homology groups (genes) provided robust evolutionary inference. Our analysis revealed substantial interspecific genomic diversity in core gene repertoires, structural features, and a transposable element (TE) landscape that shaped genome size differences and is potentially linked to phenotypic plasticity. We provide two examples of the types of analyses that become possible with this pangenome. First, the pangenome serves as a quality-aware lens, exposing discrepancies arising from assembly and annotation variability and helping separate technical artifacts from genuine biological signal. Second, the pangenome provides locus-level resolution: analysis of MYB114, a key regulator of anthocyanin accumulation, reveals lineage-specific presence–absence patterns and TE-associated regulatory variation. This pangenomic study deepens our understanding of the genetic diversity and genome evolution of Rosa species and establishes a resource to resolve the genetic bases of key traits, thereby informing and supporting rose breeding.

The food environment plays an important role in shaping diets, yet evidence in Zambia is limited. Traditional fermented foods such as mabisi, a Zambian traditional fermented milk, are beneficial and recommended as part of a healthy diet in the Zambian food-based dietary guidelines. Using components of Photovoice, this study explored factors influencing the consumption of healthy diets in the urban and rural food environments of two Zambian districts, Choma and Chipata, which differ in mabisi consumption. Fifty-seven participants shared their perspectives, revealing that despite the differences in mabisi consumption, the two food environments were very similar. The food environment in both districts largely depended on agriculture for the participants' diets and income. Rural participants depended on farming and gathering wild fruits and vegetables, while the urban participants had greater access to less nutrient-dense foods. Food safety and poor hygiene conditions were major concerns for most participants, particularly in urban Chipata where foods were sold on the streets uncovered and near garbage and/or sewer lines. As a result, packaged ultra-processed foods were perceived to be safer and healthier than less processed foods sold in the market. The findings reveal a paradox: although informal markets are vital sources of fresh and healthy food, they are viewed as unhygienic and risky, driving consumers toward ultra-processed foods perceived as safer. Even mabisi, which was generally considered a healthy food, was often perceived as unsafe because it was sold in dirty containers. Interventions must focus on improving hygiene and safety in informal markets, enhancing consumer awareness about the risks of ultra-processed foods, and ensuring that safe, nutritious foods are both accessible and affordable, especially for low-income populations in both urban and rural settings.

Biological control is a sustainable strategy to combat agricultural pests. Yet, legislation increasingly restricts importing nonnative biocontrol agents. Thus, selective breeding of biocontrol traits is suggested to enhance performance of existing biocontrol agents. Genomic prediction, where genomic data are used to estimate the genetic merit of an individual for specific traits, is an alternative to exploit genetic variation for the improvement of native biocontrol agents. This study aims to establish a proof of principle for genomic prediction in insect biocontrol agents, using wing morphology traits in the model parasitoid Nasonia vitripennis Walker (Pteromalidae). We performed genomic prediction using a genomic best linear unbiased prediction (GBLUP) model, using 1,230 individuals with 8,639 SNPs generated by genotyping-by-sequencing (GBS). We used individuals from 2 generations from the outbred HVRx population, 717 individuals from generation 169 (G169) and 513 individuals from generation 172 (G172). To assess genomic prediction accuracy, we used across generation validation (forward validation for G172 from G169 and backward validation for G169 from G172) and also 5-fold cross-validation. For size-related traits, including tibia length, wing length, wing width, and second moment area, the accuracy of genomic prediction was close to 0 in both across generation validations but much higher in 5-fold cross-validation (ranging from 0.54 to 0.68). For the shape-related trait wing aspect ratio, a high accuracy was found for all 3 validation strategies, with 0.47 for across generation forward validation (AGFV), 0.65 for across generation backward validation (AGBV), and 0.54 for 5-fold cross-validation. Overall, genomic selection in insect biocontrol agents with a relative small effective population size seems promising. However, factors such as the biology of insects, phenotyping techniques, and large-scale genotyping costs still challenge the application of genomic selection to biocontrol agents.

Abstract Not all odors influencing mating behavior evolve as sex pheromones. Female butterflies’ post-mating odors have been considered species-specific anti-aphrodisiac pheromones shaped by sexual selection but may also serve broader ecological roles shaped by natural selection. Males transfer odors to females that repel rivals, yet the widespread use of these compounds across phyla makes them targets for eavesdropping, such as by phoretic egg parasitoids. We show that in cabbage white butterflies ( Pieris spp.), these odors are highly variable and attract parasitoids, deter predators, and influence oviposition. Using gas chromatography and electroantennography, we demonstrate that odor emission and perception lack species-specificity: compounds once thought unique to P. brassicae and P. rapae are shared across Pieridae. In P. napi , odor variation among populations correlates with parasitoid pressure, but not with latitude, genetic distance, or mating frequency, suggesting ecological rather than sexual drivers. In P. brassicae , CRISPR/Cas9 disruption of odor perception alters oviposition and increases susceptibility to parasitism. Moreover, these odors render females unpalatable to birds. Together, our results show that post-mating odors in Pieris butterflies may act as aposematic signals. We provide evidence that these signals evolve under multiple selective pressures, balancing deterrence of mates and predators, parasitoid avoidance, and host-plant interactions. These findings suggest that chemical signals should be viewed as integrating ecological and reproductive pressures, rather than being interpreted solely through the lens of sexual communication.

Background: The fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith), a highly invasive pest of maize and other crops, was first reported in Ethiopia in 2017, where it has caused severe yield losses. Two sympatric host-associated strains, corn (C) and rice (R)are recognized. However, the genetic diversity and population structure of Ethiopian FAW remain poorly understood. Methods: We analyzed 250 larvae collected from maize and sorghum fields across four Ethiopian regions via mitochondrial cytochrome oxidase subunit I (COI) and nuclear triose phosphate isomerase (Tpi) markers. Results: COI data revealed 60.6% rice (R) and 39.4% corn (C) strains in Ethiopia. Tpi analysis classified all individuals as the corn strain, indicating a marker discrepancy, likely due to interstrain hybridization. Six COI haplotypes were identified, dominated by two widely distributed haplotypes (Hap1 = 60.8%, Hap3 = 37.1%). Neutrality tests revealed a significantly positive Tajima's D (D = 4.68, p < 0.001) and Fu and Li's F*, indicating an excess of intermediate-frequency variants consistent with population structure and lineage admixture rather than recent demographic expansion. AMOVA detected weak but significant genetic differentiation among regions (DST = 0.044), while PCoA revealed two major clusters corresponding to mitochondrial lineages rather than geographic origin. Conclusions: These findings provide the first comprehensive genetic characterization of S. frugiperda in Ethiopia and suggest multiple introductions and subsequent lineage mixing. The observed mito-nuclear discordance and strong population structure highlight the importance of genome-wide analyses to better resolve invasion history and inform sustainable management strategies.

A particularly well-studied evolutionary model is the vinegar fly Drosophila melanogaster, a cosmopolitan insect of ancestral southern-central African origin. Recent work suggests that it expanded out of Africa ∼9,000 years ago, and spread from the Middle East into Europe ∼1,800 years ago. During its global expansion, this human commensal adapted to novel climate zones and habitats. Despite much work on phenotypic differentiation and adaptation on several continents (especially North America and Australia), typically in the context of latitudinal clines, little is known about phenotypic divergence among European populations. Here, we sought to provide a continent-wide study of phenotypic differentiation among European populations of D. melanogaster. In a consortium-wide phenomics effort, we assayed 16 fitness-related traits on a panel of 173 isofemale lines from 9 European populations, with the majority of traits measured by several groups using semi-standardized protocols. For most fitness-related traits, we found significant differentiation among populations on a continental scale. Despite inevitable differences in assay conditions among labs, the reproducibility and hence robustness of our measurements were overall remarkably good. Several fitness components (e.g., viability, development time) exhibited significant latitudinal or longitudinal clines, and populations differed markedly in multivariate trait structure. Notably, populations experiencing higher humidity/rainfall and lower maximum temperature showed higher viability, fertility, starvation resistance, and lifespan at the expense of lower heat-shock survival, suggesting a pattern of local adaptation. Our results indicate that derived populations of this tropical fly have been shaped by pervasive spatially varying multivariate selection and adaptation to different climates on the European continent.

Sorting of maize ears based on husk cover at harvest may be considered as an approach to minimise the aflatoxin (AF) levels in maize grain intended for consumption. Aflatoxins are known natural human carcinogens produced by certain species of Aspergillus section (sect.) Flavi and impair livestock productivity. We investigated the influence of maize ear husk cover inadequacy on the natural infection of preharvest maize with Aspergillus sect. Flavi and contamination with AFs thereof. Additional investigated factors that may influence maize Aspergillus sect. Flavi infection and AF contamination were rainfall intensity, field burning, insect pest infestation, seed maturity and crop rotation. Maize and soil samples were collected over two seasons from two climatically contrasting regions of Zambia. One region was in the wetter Agro-Climatic Zone (ACZ) and another in the drier ACZ. Plate count technique on modified rose Bengal agar was used to quantify Aspergillus sect. Flavi densities in maize and soil. AF levels in maize were determined by High-Performance Liquid Chromatography with immunoaffinity column clean-up. Aspergillus sect. Flavi was present in soils. On maize, Aspergillus sect. Flavi was mainly detected under dry spell conditions despite being detected in all soils. Similarly, AF in maize was only detected under dry spell conditions. Findings showed that inadequate husk cover alone did not influence Aspergillus sect. Flavi infection of maize and subsequent AF contamination. Rather, dry spell with late rains predisposed the Aspergillus sect. Flavi infection and AF contamination. Insect pest incidence was the second most important factor aggravating the Aspergillus sect. Flavi infection.

Rosa , belonging to the family Rosaceae, encompasses more than 150 species which are widely distributed in the northern hemisphere. Renowned for their beauty, roses are cultivated throughout the world for ornamental purposes and the production of essential oils and perfumes. Despite their cultural and commercial significance, the genomic resources of wild Rosa species have not been studied comprehensively, hampering the understanding of their genetic diversity, evolutionary history, and breeding potential. Here we report on high-quality de novo genomes for Rosa sericea and Rosa rugosa . By integrating these two de novo genomes with existing public genomic resources, we have built a Rosaceae panproteome and a Rosa pangenome (spanning wild, traditional garden, and modern rose lineages) using a De Bruijn graph (DBG)-based approach. A maximum likelihood (ML) phylogeny of 18 Rosa haplotypes based on 4,367 single-copy core homology groups (genes) provided robust evolutionary inference, confirming the basal position of R. sericea , and enabled a gene-based macrosynteny analysis across the pangenome. Our analyses revealed significant genomic diversity among species, extensive variation in core gene content, and lineage-specific transposable element (TE) expansion patterns that contribute to the variation in Rosa genome size and to species-specific adaptations. The pangenome also revealed biased diversification of homology groups potentially linked to phenotypic plasticity in Rosa . Specifically, our analysis of the rose scent-related gene family, NUDX1 , uncovered its evolutionary trajectory in Rosa , in which TEs insertions provided putative novel regulatory elements that facilitated adaptive evolution in metabolic pathways. This pangenomic study deepens our understanding of the genetic diversity and evolution of traits within the Rosa genus. In addition, the findings lay the foundation for future efforts to understand the genetic mechanisms driving trait evolution, which can support rose breeding. ### Competing Interest Statement The authors have declared no competing interest.

Gene drive technology may be a valuable tool for addressing several contemporary challenges, including combating disease vectors, conserving biodiversity, and controlling agricultural pests. Homing gene drives spread through a population by copying themselves onto the homologous chromosome in the germline of heterozygous individuals. However, it is possible that resistance will evolve against homing gene drives, especially if the goal is to suppress or eliminate a pest population so that resistance alleles have a large selective advantage over the gene drive. Resistance can result from a simple mutation at the drive’s target site, which is found in many studies but can potentially be avoided by improving drive design. However, a more complex polygenic type of resistance could also evolve through selection on standing genetic variation that affects the efficiency of the spread of the gene drive. In this study, we test an efficient homing gene drive in genetically diverse lines of Drosophila melanogaster , collected from across Europe by the DrosEU Consortium. We find that the gene drive shows considerable variability in homing efficiency, but that none of this variability can be ascribed to heritable genetic effects. Selection for complex resistance is thus unlikely and will be inefficient, probably still giving a gene drive enough time to fixate in the population. However, although our tested gene drive targets a highly conserved haploinsufficient gene with two gRNAs, we find simple resistance alleles in viable offspring. Half of these are the product of end-joining repair instead of homing and may still carry heavy fitness costs. However, the other half are the result of partial homing events. These alleles indicate that resistance could likely evolve against this gene drive in a simple, non-polygenic way. Therefore, more effective strategies may be required to address simple resistance mutations, whereas complex resistance may be unlikely to pose a substantial barrier to the employment of at least certain types of gene drive. ### Competing Interest Statement The authors have declared no competing interest. The Dutch Graduate School for Production Ecology & Resource Conservation (PE&RC)

ABSTRACTNatural microbial communities continually encounter novel species that may successfully establish or simply be transient, yet both outcomes can alter the resident community composition and function. Preserving natural microbial communities and innovating synthetic ones requires insight on the immediate and long-term impact of species introductions on both composition and function. For instance, it remains unclear whether there are gradual and long-term impacts from repeated invasions where the introduced species fails to establish – so-called failed invaders. To investigate the persistent impacts by failed invaders, we present an experimental test of community stability over multiple generations against repeated novel species introduction. We propagated a natural microbial community from a traditional fermented milk beverage for approximately 100 generations, with or without, repeated introduction ofEscherichia coliat each transfer. Community function was determined by metabolic profiling, and we observed alterations therein immediately afterE. coliintroduction, followed by recovery, or rebound once ceased. In contrast to this proxy of community function, changes in the bacterial community composition were never detected. Our results evidence that community composition and function do not necessarily respond in parallel to an introduced species, potentially due to genotypic changes below species level detection or metabolic plasticity. Our work shows an ability for functional recovery in microbial communities and contributes insight on long-term community stability to sustained disturbances.

Invasive aspergillosis, caused by Aspergillus fumigatus, represents a critical public health concern, particularly due to increasing resistance to triazole antifungals linked to TR34/TR46 cyp51A haplotypes. In our genomic epidemiology study of 157 A. fumigatus isolates from Dutch environmental hotspots and two clinical centers, we identified near-identical genomes in several environmental and patient isolates, indicating a probable link. However, the geographic and temporal data alone are not sufficient to explain direct transmission pathways. Furthermore, a comparison with more than 1,200 globally sourced genomes revealed the extensive dissemination of certain clonal groups across multiple distant regions, raising significant challenges for the utility of genomic epidemiology. The discovery of high genetic diversity and the widespread distribution of some clonal groups challenges current understanding, suggesting that in most cases, tracing the precise source of individual infections will remain extremely difficult, even with increased sampling. In addition, we uncovered that the multi-triazole-resistant TR34/TR46 cyp51A haplotypes are associated with resistance to non-triazole fungicides such as benzimidazole, succinate dehydrogenase inhibitor, and quinone outside inhibitor classes, strongly suggesting an exposure history to multiple agricultural fungicides in these environmental hotspots. This resistance beyond the azole class suggests that strategies targeting only triazoles may be insufficient. Our findings challenge current paradigms and carry significant implications for One Health research and global public health strategies, underscoring the urgency of multidisciplinary approaches to tracking and monitoring fungal resistance.IMPORTANCEOur study links triazole-resistant A. fumigatus isolates cultured from three environmental hotspots to cases of aspergillus disease in two hospitals in the Netherlands. Genome comparisons of isolates from environmental hotspots and patients showed multiple near-identical linked genotypes, consistent with a route of transmission from the environment to patients. Linked cases without clear transmission routes emphasize the need to better understand the ecology of this fungus. Since patients often do not visit rural hotspots, research should explore complex, long-distance transmission mechanisms, including airborne dispersal of conidia or non-agricultural habitats. The multi-fungicide resistance phenotype suggests reducing one class of fungicides alone may not lower resistance selection. Instead, interventions should target modifying environments that promote the growth of fungicide-resistant A. fumigatus and prevent the escape of resistant spores from these hotspots to mitigate the burden of environmental resistance effectively.

Humans are exposed to the mold Aspergillus fumigatus via inhalation, and infections are increasingly resistant to triazole-class antifungals. Ecologically, this fungus is a ubiquitous saprotroph found in terrestrial environments. Although triazole-resistant A. fumigatus is found in large quantities in specific agricultural environments, it is not clear how much these contribute to the overall exposure of individuals to antifungal resistance. Triazoles are also used to protect a wide range of products unrelated to agriculture, and therefore, it could not be excluded that the resistance observed in agricultural settings may be the result of selection beyond agricultural sources. In the case of A. fumigatus, genomics cannot reliably link resistant isolates to specific environmental sources. Therefore, we used a spatial sampling approach to measure population trends in triazole resistance. We conducted a large-scale, unbiased air sampling throughout the Netherlands using a citizen science approach. We find that $\sim $4$\%$ of over 60K screened colonies are resistant to clinical triazoles. Modeling resistance data with spatial land-use data shows that agricultural land use, particularly flower bulbs and greenhouses, can predict peaks in antifungal resistance in airborne A. fumigatus in the Netherlands. Furthermore, genotyping resistant isolates suggests land-use-associated niche differentiation between two dominant resistance haplotypes, with only one of the two showing a significant association with agricultural land use. By linking triazole resistance to land use, this work informs necessary policy-driven changes to reduce human exposure to antifungal-resistant A. fumigatus, and suggests that similar spatial patterns in antifungal resistance may occur in other agriculture-associated fungi as well.

Major changes in genetic variation are generally considered deleterious to populations. The massive biodiversity of insects distinguishes them from other animal groups. Insect deviant effective population sizes, alternative modes of reproduction, advantageous inbreeding, endosymbionts, and other factors translate to highly specific inbreeding and outbreeding outcomes. We review the evidence for inbreeding and outbreeding depression and consequences across wild and captive insect populations, highlighting conservation, invasion, and commercial production entomology. We not only discern patterns but also explain why they are often inconsistent or absent. We discuss how insect inbreeding and outbreeding depression operates in complex, sometimes contradictory directions, such as inbreeding being detrimental to individuals but beneficial to populations. We conclude by giving recommendations to (a) more comprehensively account for important variables in insect inbreeding and outbreeding depression, (b) standardize the means of measuring genetic variation and phenotypic impacts for insect populations so as to more reliably predict when inbreeding or outbreeding depression applies, and (c) outline possible remediation options, both nongenetic and genetic, including revision of restrictive international trade laws.

AbstractAphids display remarkable adaptability to pest control strategies and their partheno-genetic reproduction results in rapid numerical increase of higher-fitness clones. Con-sequently, a high prevalence of only a few clonal lines could indicate positive selection for these genotypes, potentially reflecting adaptation to pest control methods. Here, we investigated the clonal diversity and population genetic structure of the green peach aphidMyzus persicaeusing microsatellite markers, in both organic and conventionally managed Dutch sweet pepper greenhouses over four consecutive years. In total, 26 distinct multilocus genotypes (MLG) were detected, with higher clonal diversity in organic than in conventional greenhouses. Strikingly, a single MLG dominated conventional greenhouses in 2019, only to be completely replaced by a new dominant MLG by 2022. Whole-genome sequencing of 15 sampled lines — seven sharing the same MLG and eighth with unique MLGs — revealed that all aphids with the dominant MLG of 2019, collected from various locations and over multiple years, originated from a single parthenogenetic ancestor. Our findings indicate that the population genetic structure ofM. persicaediffers between organically and conventionally managed sweet pepper greenhouses. The presence of dominant MLGs in conventional crop systems may suggest positive selection or evolutionary forces such as a founder effect. Understanding the forces driving these differences in population genetic structure and their impact on the efficacy of biocontrol agents will further help us improve control strategies forM. persicaein greenhouse crops.

Through partitioning of ecological niches, several fungi are able to coexist on the same host crop. In (partial) absence of niche partitioning, competitive exclusion among fungi can occur. Competitive exclusion is one of the bases for biocontrol. We investigated fungal correlations, in terms of relative abundance of the fungi, in pre-harvest maize, as a natural ecosystem model. Internal mycobiome fungal relative abundance of maize was used to establish correlations. The maize had been harvested from dry and wet agro-ecological zones of Zambia. The relative abundances of the fungal genera were determined using DNA amplicon sequencing. For this study, positive or absence of correlations between fungal genera signified good niche partitioning (co-existence), whereas negative correlations signified poor niche partitioning and potential for competitive exclusion. When species compete within one niche (competitive exclusion), we may expect to detect higher levels of mycotoxins—since mycotoxins are considered antagonistic agents aimed at defending or invading an ecological niche. To estimate the importance of mycotoxins in competitive exclusion, we measured the influence of the fungal correlations on levels of fumonisin-B1 (FB1) in the maize. FB1 data were derived from a previous study on the maize, determined by HPLC. Results showed that Sarocladium and Stenocarpella had the strongest significant negative correlation with Fusarium, suggesting poor niche partitioning and potential for antagonism of these genera with Fusarium. Furthermore, higher levels of Stenocarpella resonated with lower levels of FB1 and vice versa. It was also observed that, when Sarocladium was in low abundance (< 10