Search Results (168)

The soft scale Toumeyella martinezae infests the arborescent cactus Myrtillocactus geometrizans. This scale is, in turn, parasitized by the wasp Mexidalgus toumeyellus and forms a mutualistic relationship with the ant Liometopum apiculatum. This study assessed how ant and/or parasitoid presence influenced parasitism rates and the population growth of the scale insect. Experimental treatments included scale populations with ant access (control) or ant exclusion, and parasitoid exclusion with ant access. Scale population growth rates were estimated using Lefkovitch projection matrices, built based on the individual monitoring of approximately 5400 scales. The average parasitism rate was higher in the “with ants” treatment (18.66%) than under ant exclusion (5.42%). In the absence of parasitoids, the scale population growth rate (λ = 1.532) was 8% higher than in the control treatment (λ = 1.423). Population growth was negative (λ = 0.636) when ants were excluded. These results indicate that interaction with the mutualistic ant is the primary factor sustaining a positive scale population growth. In contrast, the impact of the parasitoid alone is insufficient for effectively controlling the soft scale pest. Full article

Mycorrhizal symbiosis represents a ubiquitous mutualistic relationship in nature, wherein mycorrhizal fungi enhance the host plant’s ability to absorb water and nutrients from the soil. In return, the host plant supplies the fungi with essential nutrients necessary for their metabolic activities. However, research focusing on the regulatory mechanisms governing mycorrhizal symbiosis in Dendrobium officinale remains limited. This study systematically investigates the regulatory mechanisms of mycorrhizal symbiosis on transcriptional synthesis in D. officinale by establishing a mycorrhizal symbiotic system, complemented by phenotypic observation, physiological measurement, and transcriptome sequencing. The results indicate that mycorrhizal symbiosis promotes both growth and nutrient absorption in D. officinale, concurrently increasing polysaccharide content. Through transcriptome analysis, we identified 59 differentially expressed genes associated with polysaccharide metabolism, alongside key genes and transcription factors integral to the regulatory network. Notably, the glycosyltransferase gene DoUGT83A1 was found to negatively regulate the mycorrhizal symbiotic system when heterologously expressed in tomato. This study provides a fundamental theoretical basis for elucidating the molecular mechanisms underlying polysaccharide synthesis in D. officinale and offers new insights for optimizing cultivation practices to enhance medicinal quality. Full article

Longleaf pine forests are economically important habitats that stabilize and enrich the soil and store carbon over long periods. When mixed with oaks, these forests provide an abundance of lichen habitats. The tree canopy lichens promote greater moisture capture and retention and encourage canopy insects. Ground lichens limit some vascular plant germination and growth, promoting a more open and healthy pine community. There is a longstanding mutualistic relationship between longleaf pine habitat and lichens. Longleaf pine habitat has a long history of natural summer burning, which promotes a diverse understory and limits tree densities. Lichen diversity exceeds vascular plant diversity in many mature longleaf pine habitats, yet information on the impacts of prescribed fire on lichen species in these habitats is limited. We assessed lichen diversity and abundance before and after a prescribed ground fire in a longleaf pine/wiregrass habitat near Ocala, Florida. Pre-burn, we found greater lichen abundance and diversity on hardwoods, primarily oak species, than on pines. Post-burn, lichen abundance on hardwoods dropped overall by 28%. Lichen abundance on conifers dropped overall by 94%. Ground lichen species were basically eliminated, with a 99.5% loss. Our study provides insights into retaining lichen diversity after a prescribed burn. Hardwood trees, whether alive or standing dead, help retain lichen biodiversity after burning, whereas conifer trees do not support as many species. Landscapes may need to be actively managed by raking pine needle litter away from ground lichen beds, moistening the ground, or removing some lichen material before the burn and returning it to the site post-fire. Based on these results, we suggest retaining some oaks and conducting burns in a mosaic pattern that retains unburned areas. This will allow for lichens to recover between burns, significantly enhancing biodiversity and the ecological health of these longleaf pine communities. Full article

The brown planthopper, Nilaparvata lugens, a major rice pest, harbors yeast-like symbionts (YLSs) that form mutualistic relationships with the host, significantly influencing its development and reproduction. As proteasome subunits play major roles in the assembly and functional maintenance of the proteasome, but their regulation on the YLSs in N. lugens are unclear. In this study, we analyzed the spatiotemporal and temporal expression patterns of five N. lugens proteasome subunits (NlPSMA2, NlPSMB5, NlPSMC4, NlPSMD10, NlPSMD13), and further verified their functions on the transovarial transmission of YLSs, in addition to the reproduction of N. lugens, based on RNA interference (RNAi). The results showed that NlPSMA2, NlPSMB5, NlPSMC4, NlPSMD10, and NlPSMD13 were highly expressed in ovarian follicular cells of N. lugens upon sexual maturation. After suppressing the expression of these genes by RNAi, N. lugens exhibited a shortened lifespan, abnormal pear-shaped follicles, and impaired oviposition capacity, but the number of YLSs in the whole body and the oocyte of N. lugens were significantly increased. These results indicate that the proteasome subunits play crucial roles in the reproduction of N. lugens and the transovarial transmission of its YLSs. Full article

A study was conducted to examine the effects of the spray application of nine antifungal products, including microbial-derived fungicides, plant-derived fungicides, and chemical fungicides, on the grass Achnatherum inebrians that was either host to Epichloë gansuensis (E+) or E. gansuensis-free (E−) and that was exposed to Blumeria graminis, the fungal pathogen causing powdery mildew. The Epichloë endophyte is a seed-borne mutualistic biotrophic fungus whose growth is fully synchronized with the host grass. Bl. graminis is a biotrophic pathogen that continually infects leaves and stems via conidia, the formation of appressoria, leading to the presence of haustoria in epidermal cells. Prior to fungicide application, the presence of endophytes significantly increased the resistance of A. inebrians to powdery mildew and was able to increase the chlorophyll content. However, the positive effects of the Epichloë endophyte on the plant were suppressed with the use of some fungicides and the increase in the number of sprays, but the reciprocal relationship between the Epichloë endophyte and the plant was not significantly disrupted. Full article

Perennial ryegrass (Lolium perenne), an important forage and turfgrass species, can establish a mutualistic symbiosis with the fungal endophyte Epichloë festucae var. lolii. Although the physiological and ecological impacts of endophyte infection on ryegrass have been extensively investigated, the response of the soil microbial community and nitrogen-cycling gene to this relationship has received much less attention. The present study emphasized abundance and diversity variation in the AOB-amoA, nirK and nosZ functional genes in the rhizosphere soil of the endophyte–ryegrass symbiosis following litter addition. We sampled four times: at T₀ (prior to first litter addition), T₁ (post 120 d of 1st litter addition), T₂ (post 120 d of 2nd litter addition) and T₃ (post 120 d of 3rd litter addition) times. Real-time fluorescence quantitative PCR (qPCR) and PCR amplification and sequencing were used to characterize the abundance and diversity of the AOB-amoA, nirK and nosZ genes in rhizosphere soils of endophyte-infected (E+) plants and endophyte-free (E−) plants. A significant enhancement of total Phosphorus (P), Soil Organic Carbon (SOC), Ammonium ion (NH₄⁺) and Nitrate ion (NO₃⁻) contents in the rhizosphere soil was recorded in endophyte-infected plants at different sampling times compared to endophyte-free plants (p ≤ 0.05). The absolute abundance of the AOB-amoA gene at T₀ and T₁ times was higher, as was the absolute abundance of the nosZ gene at T₀, T₁ and T₃ times in the E+ plant rhizophere soils relative to E− plant rhizosphere soils. A significant change in relative abundance of the AOB-amoA and nosZ genes in the host rhizophere soils of endophyte-infected plants at T₁ and T₃ times was observed. The experiment failed to show any significant alteration in abundance and diversity of the nirK gene, and diversity of the AOB-amoA and nosZ genes. Analysis of the abundance and diversity of the nirK gene indicated that changes in soil properties accounted for approximately 70.38% of the variation along the first axis and 16.69% along the second axis, and soil NH₄⁺ (p = 0.002, 50.4%) and soil C/P ratio (p = 0.012, 15.8%) had a strong effect. The changes in community abundance and diversity of the AOB-amoA and nosZ genes were mainly related to soil pH, N/P ratio and NH₄⁺ content. The results demonstrate that the existence of tripartite interactions among the foliar endophyte E. festucae var. Lolii, L. perenne and soil nitrogen-cycling gene has important implications for reducing soil losses on N. Full article

Insects and their endosymbionts have a close mutualistic relationship. However, the precise nature of the bacterial endosymbiont-mediated interaction between host plants and whitefly Bemisia tabaci MEAM1 is still unclear. In the present study, six populations of Bemisia tabaci MEAM1 sharing the same genetic background were established by rearing insects for ten generations on different host plants, including poinsettia, cabbage, cotton, tomato, and tobacco, and an additional population was reared on cotton and treated with antibiotics. The physiological and nutritional traits of the insects were found to be dependent on the host plant on which they had been reared. Systematic analysis was conducted on the endosymbiont titers, the amino acid molecules and contents, as well as developmental and oviposition changes in the MEAM1 populations reared on each host plant tested. The results indicate that B. tabaci contained the primary symbiont Portiera and the secondary symbionts Hamiltonella and Rickettsia. In addition, the titer of endosymbiotic bacteria in females is higher than that in males. Among the MEAM1 populations reared on each host plant, the variation pattern of Portiera titer generally corresponded with changes in biological characteristics (body length, weight and fecundity) and AA contents. This suggests that changes in the amino acid contents and biological characteristics of different B. tabaci populations may be due to changes in the Portiera content and the differences in the nutrition of the host plants themselves. Our findings were further confirmed by the reduction in Portiera with antibiotic treatment. The amino acids, body size, body weight, and fecundity of B. tabaci were all reduced with the decrease in the Portiera titer after antibiotic treatment. In summary, our research revealed that host plants can affect the content of symbiotic bacteria, particularly Portiera, and subsequently affect the nutrition (i.e., the essential amino acids content) of host insects, thus changing their biological characteristics. Full article

Eogystia hippophaecola (Hua, Chou, Fang & Chen, 1990) is a major borer pest of sea buckthorn (Hippophae rhamnoides L.), and during its four-year growth period, its feeding site shifts progressively from the trunks to the roots, establishing a complex mutualistic relationship with the host. The factors driving the host-shifting behavior of E. hippophaecola larvae remain unclear. In this study, we compared the nutrient composition of the roots and trunks, measured the activity of metabolizing enzymes in E. hippophaecola, and analyzed secondary metabolites in both the roots and trunks following infestation using LC-MS. Sugars, proteins, fats, and free amino acids were more abundant in the roots, and larvae feeding on this part exhibited a stronger resistance. Non-targeted metabolomics identified 8493 metabolites in total. The trunks exhibited 394 DEMs compared to the roots (223 up-regulated and 171 down-regulated). Lipids and lipid-like molecules represented more than two-thirds of the total, primarily involved in steroid biosynthesis, linoleic acid metabolism, and glycerophospholipid metabolism. The significant down-regulation of key compounds, such as lecithin and linoleate, suggests that resistance metabolism is less pronounced in the trunks compared to the roots. In summary, the host-shifting behavior of E. hippophaecola larvae is primarily driven by a combination of the host’s nutritional conditions and defense mechanisms. Full article

In the face of the growing challenges of the Anthropocene—marked by climate change, biodiversity loss, and increasing rates of disease and despair—this paper explores the need for holistic solutions that integrate cultural and spiritual transformation as essential dimensions of change. Recognizing that the interconnected challenges to planetary health stem from destructive socio-political agendas and unhealthy economic structures, we underscore the importance of worldviews and value systems as root causes of social and ecological injustices. Solutions require an understanding of the complex interdependence of systems, fostering mutualistic mindsets, and healing the ‘relationship crisis’ between humans and the natural world by cultivating a deeper level of consciousness. In response to these urgent needs, we describe Earthrise—a community of engaged contemplative practice led by the Nova Institute for Health in collaboration with the Planetary Health Alliance—dedicated to spiritual and cultural transformation in the face of today’s complex crises. Through intentional spiritual relationships—with ourselves, each other, and the natural world—our community emphasizes the power of narrative co-creation in building social cohesion and collective action for environmental stewardship. Our work is not solely contemplative, but also relational and integrative—embodying values through lived practice, community, and ecological engagement. Our activities focus on developing cultural capacities and self-awareness as essential foundations for fair and sustainable social transformation. By integrating diverse perspectives, including ancestral wisdom and Indigenous knowledge systems, we enrich worldviews and deepen our connection to the planet. The Earthrise community seeks to cultivate a sense of belonging, nurturing the meaningful relationships that foster compassion and care. Central to our approach is the use of creative emergence, leveraging the arts to inspire change and catalyze new paradigms. Through this exploration of interconnected themes, we contend that spiritual and cultural transformation is vital to advancing a thriving future, where human flourishing and planetary health are understood as inseparable and interconnected goals. Full article

Benthic microbial communities are a vital component of coastal subtidal zones, playing an essential role in nutrient cycling and energy flow, and are fundamental to maintaining the stability and functioning of marine ecosystems. However, the response of benthic prokaryotic and eukaryotic microbial communities to environmental changes remains poorly understood. Herein, we conducted a nearly semimonthly annual sampling survey to investigate the temporal patterns and underlying mechanisms of benthic prokaryotic and eukaryotic microbial communities in the subtidal sediments of Sanshan Island, situated in the eastern Laizhou Bay of the Bohai Sea, China. The results showed that the temporal variations in benthic microbial communities followed a distinct seasonal pattern, with turnover playing a more dominant role in community succession. Nonetheless, contrasting temporal variations were observed in the alpha diversity of benthic prokaryotic and eukaryotic microbial communities, as well as in the dominant taxa across different microbial communities. Water temperature, dissolved oxygen, electrical conductivity, salinity, total nitrogen (TN), NH₄⁺, and PO₄³⁻ were identified as the predominant environmental drivers. The assembly of benthic microbial communities was driven by different ecological processes, in which stochastic processes mainly shaped the benthic prokaryotic communities, while deterministic processes dominated the assembly of benthic eukaryotic microbial communities. Interactions within benthic microbial communities were primarily characterized by mutualistic or cooperative relationships, but the ability of prokaryotic and eukaryotic microbial communities to maintain stability under environmental disturbances showed notable differences. These results shed light on the temporal dynamics and potential driving mechanisms of benthic prokaryotic and eukaryotic microbial communities under environmental disturbances, highlighting the distinct roles of prokaryotic and eukaryotic communities in coastal subtidal zones and providing valuable insights for the management and conservation of coastal subtidal marine ecosystems. Full article

Vineyard mealybugs (Hemiptera: Pseudococcidae) are economic pests in vineyards, demanding integrated control strategies. Several ant species can facilitate mealybug infestation by protecting them from natural enemies in a mutualistic relationship known as trophobiosis. In the frame of an ant management system, the provision of sugary liquid has proved worldwide to improve mealybug control. In the present study, a field trial was carried out within an important vineyard cultivation area of northern Italy with the aim of testing a lower density (80/ha) of sugar dispenser to facilitate the practicality of this method. The sugar dispensers tested, along with predators and parasitoid release, were effective in reducing mealybug infestations by 22% and resulted in a double increase in larval density of the predator Cryptolaemus mountrouzieri Mulsant. Mealybug parasitism was in general high, but it was not improved by sugar dispensers at this density. Our field validation confirms the importance of ants in mealybug infestation dynamics, and the benefits of ant management in the context of integrated strategies against mealybugs. Full article

This study investigates the competitive and cooperative relationships within urban agglomerations, specifically focusing on the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). Using the Lotka–Volterra model from ecology, the research aims to analyse and predict the dynamic relationships among cities in this area. The purpose is to understand how competition and cooperation influence regional integration, and their complex economic connections. This paper employs both qualitative and quantitative methods, including time-series analysis and the application of the Lotka–Volterra model, to evaluate economic interactions and the roles of various cities or regions within the GBA. The study reveals that mutualistic, competitive, predatory, commensal, and parasitic relationships coexist among them, with core cities such as Shenzhen, Guangzhou, Hong Kong, and Macao assuming pivotal roles in shaping the overall dynamics. The findings highlight the importance of functional division, regional cooperation, and innovative collaboration to enhance sustainable development. Policy recommendations are provided to foster a balanced and integrated growth model, emphasizing inter-city cooperation, resource sharing, and avoidance of industrial homogeneity. Full article

Amphibians are the most severely threatened vertebrate group in terms of biodiversity. The microbiota that coexist in a mutualistic relationship with amphibians play a crucial role in shaping their health status, reproductive efficiency, and environmental adaptability. Understanding the relationship between amphibians and microbiota is vital for elucidating the causes of amphibian diseases and developing effective prevention and control techniques, which in turn is significant for enhancing the effectiveness of amphibian diversity conservation. The main findings of this article are as follows: Firstly, it provides an overview of the systematic assessment and analysis methods regarding the importance of amphibians and their symbiotic microbiota, detailing the primary research techniques currently employed. Secondly, it discusses the impacts of environmental and biological factors on the characteristics of amphibian symbiotic microbial communities, including dimensions such as altitude, temperature fluctuations, and host dietary habits. Finally, the future directions of research on amphibian symbiotic microbiota are examined, with five recommendations presented: (1) Establish a comprehensive sample library and database of amphibians and their symbiotic microbiota to create a solid foundation for scientific research. (2) Explore the coevolutionary paths between amphibians and symbiotic microbiota to clarify the dynamic evolutionary patterns and principles of their interactions. (3) Strengthen research on specific areas of amphibians, especially the microbial communities in the oral cavity and cloaca. (4) Enhance research on the symbiotic microbiota of the Gymnophiona. (5) Strengthen international cooperation to build cross-border research platforms and jointly promote the rapid development of global amphibian symbiotic microbiology. This article summarizes the current research progress on the interaction between amphibians and their symbiotic microbiota (not necessarily mutualistic). It discusses the conservation of amphibian biodiversity from the perspective of their symbiotic microbial communities and provides a forward-looking analysis of future research directions. It aims to provide rich background information for understanding the complexity of this symbiotic system, while also having significant value in enhancing the effectiveness of amphibian biodiversity conservation. Full article

This review highlights the emerging role of cross-kingdom RNA interference in plant–microbe interactions, particularly the transfer of sRNAs from microbes to plants and vice versa, emphasizing the importance of this mechanism in both mutualistic and pathogenic contexts. As plants adapted to terrestrial life, they formed symbiotic relationships with microbes, essential for nutrient uptake and defense. Emerging evidence underscores sRNAs, including small interfering RNAs (siRNAs) and microRNAs (miRNAs), as critical regulators of gene expression and immune responses in plant–microbe interactions. In mutualistic symbioses, such as mycorrhizal fungi and nitrogen-fixing bacteria associations, sRNAs are hypothesized to regulate nutrient exchange and symbiotic stability. In pathogenic scenarios, microbes utilize sRNAs to undermine plant defenses, while plants employ strategies like host-induced gene silencing (HIGS) to counteract these threats. We further explore the emerging role of extracellular vesicles (EVs) in sRNA transport, which is critical for facilitating interspecies communication in both pathogenic and mutualistic contexts. Although the potential of ckRNAi in mutualistic interactions is promising, the review highlights the need for further experimental validation to establish its true significance in these relationships. By synthesizing current research, this review highlights the intricate molecular dialogues mediated by sRNAs in plant–microbe interactions and identifies critical gaps, proposing future research directions aimed at harnessing these mechanisms for agricultural advancements. Full article

Cotton aphids, Aphis gossypii, are an important pest worldwide and have evolved mutualistic relationships with the invasive fire ant Solenopsis invicta. Their body color varies from pale yellow to dark green, with an increase in body size and fecundity. The body color composition in a cotton aphid colony can be influenced by biotic interactions with mutualistic ants and predatory ladybugs. However, since the distribution of nutrients varies across host plant organs, there may exist special effects of biotic interactions on the body color composition of the aphids on different plant parts. In the present study, we found that, under constant laboratory conditions, the proportions of dark green morphs varied among the cotton aphids distributed on different parts of a cotton seedling, with significantly higher proportions on the stems, petioles, and sprouts (SPSs) than on leaves. The presence of mutualistic fire ants significantly increased the proportion of dark green morphs in the cotton aphid colony, but with a reduction in aphid body size, compared to the untended individuals. In contrast, the introduction of a predatory seven-spotted ladybug, Coccinella septempunctata, dramatically decreased the proportion of dark green morphs on SPSs, but not on leaves, leading to a reduction in the proportion of the whole colony. These results illustrate a spatial variation in the proportions of dark green morphs on host plants in cotton aphids, which may be an adaptive strategy used by the aphids to gain benefits and/or minimize costs in the interactions with mutualistic ants and predatory ladybugs. Full article