Search Results (313)

The papaya aril is a specialized seed appendage that has been reported to contain germination-inhibiting substances and usually requires removal before seed germination, thereby limiting breeding efficiency. However, the cellular origin and candidate molecular regulators of papaya aril development remain poorly understood. To investigate the early developmental process and candidate regulatory genes of the papaya aril, we combined histological analysis, bulk RNA-seq, and single-cell RNA-seq. Histological observations suggested that aril differentiation begins around 10 days after pollination (DAP) in the funiculus region. Based on this initiation stage, bulk RNA-seq profiling of seeds at 5, 10, and 15 DAP identified genes with initiation-stage-specific expression and prioritized candidate genes potentially related to seed appendage development, including CpRING-like, CpMBR2, and CpNDR8. Single-cell RNA-seq of seeds at 10 and 15 DAP annotated a putative aril cell population and reconstructed its developmental trajectory, revealing five trajectory-associated genes: CpATJ3, CpDYL1, CpGRP-like, CpHIRD11, and CpERD15. Integrative analysis of bulk and single-cell transcriptomic datasets further identified three candidate genes potentially involved in aril development: CpFER3, CpUVI4, and CpCEP1. These findings support the funiculus region as the likely anatomical origin of the papaya aril and provide candidate genes for future functional validation. Full article

The homogenization of landscapes and reduction in floral diversity have increasingly led to low diversity in pollen diets for honey bees. In this study, we examined the effects of monofloral pollen diets based on wind-pollinated (Corylus sp., Pinus sp.) and insect-pollinated plants (Brassica napus L., Phacelia sp., Solidago sp., Fagopyrum sp.) on the development of hypopharyngeal glands (HPGs), activities of enzymatic (AST, ALT, ALP, GGTP) and non-enzymatic (urea, uric acid) biomarkers, as well as magnesium, calcium, and phosphorus concentrations in the hemolymph and fat bodies from different locations (tergite 3, 5 and sternite) in worker bees. Even a small (10%) addition of pollen to sugar candy stimulated the development of acini compared to the control group, with phacelia, buckwheat, and goldenrod pollen having the strongest effects. The largest acini developed in the 14-day-old bees fed with Phacelia pollen, whereas the collecting duct diameters were significantly reduced in all the pollen-supplemented groups. Enzymatic biomarker activities were the highest in the hemolymph of newly emerged bees and increased with age across all the tissues, particularly in tergite 5, with the highest activities recorded in the bees fed with insect-pollinated plant pollen. Non-enzymatic parameters and ion concentrations also varied with tissue type and segmental location, generally increasing with age and reaching the highest values in tergite 5. Regardless of the tissue (the fat body vs. hemolymph), the bees fed a diet containing pollen from Brassica napus, Phacelia, Solidago, and Fagopyrum had higher concentrations of calcium, magnesium, and phosphorus, while the effects of hazel and pine pollen were less pronounced. These findings suggest that even limited pollen supplementation can positively shape the morphological and biochemical physiology of worker bees. Understanding these relationships is crucial for developing strategies to support bee health under increasing environmental pressures and changing floral availability. Full article

The effects of fungicides on pollinators remain relatively understudied despite their widespread use and high likelihood of environmental exposure. We assessed the effects of a single exposure to the commercial formulation Tebucur^® 250 EW (containing tebuconazole as the active ingredient) on learning and memory in Bombus terrestris workers. Using the Free-Moving Proboscis Extension Response (FMPER) paradigm, bees were exposed to two concentrations: 9.4 µg of tebuconazole per mL (group T 1/100) and 94 ng of tebuconazole per mL (group T/10,000) of tebuconazole through either pure sucrose (Method 1) or Tebucur^® 250 EW-supplemented sucrose (Method 2) during conditioning. No significant differences between groups were detected during the learning phase (all p > 0.05). In contrast, significant differences emerged during the memory test at the earliest time point (5 min). In Method 1, bees exposed to the higher concentration (treatment group T 1/100) showed significantly lower performance compared to the control group (p < 0.05). In Method 2, the lowest performance was observed in the group exposed to the lower concentration (treatment group T 1/10,000; p < 0.01). No significant differences were detected at later time points (10 and 30 min). These results indicate that a single exposure to Tebucur^® 250 EW (active ingredient: tebuconazole, 250 g/L) can affect short-term memory in bumblebees without impairing initial learning performance. Although the observed effects were subtle and time-limited, they may have important implications for foraging efficiency and pollination under natural conditions. Full article

Adequate pollination of pollinator-dependent crops relies on the abundance and diversity of pollinators, and any temporal mismatch can lead to decreased productivity. Induced off-season flowering is widely used to anticipate the blooming time and to have a favorable market to generate greater economic income. However, the relationship between off-season flowering, effective pollination, and crop yield remains poorly understood. In this study, we compared pollinator and yield metrics of mango among its natural and off-season flowering across two years. We found that the composition, richness, and abundance of their effective pollinators varied across flowering seasons. Remarkably, blowflies were the floral visitors that deposited the highest number of pollen grains per visit and were the most important pollinators during the off-season, while honeybees and stingless bees were more important in the natural season. Mango yield was more positively related to the abundance of wild pollinators in both seasons than to honeybees. However, in both flowering seasons, mango trees suffered from pollen limitation and had a high incidence of malformed fruits. These findings highlight the important role of wild pollinators in maintaining and improving the mango yield and quality, mainly during the induced flowering season, improving the income to mango producers and increasing food security. Full article

The impacts of climate change on Mediterranean weed flora were investigated to inform future weed management strategies. Projections indicate that rising temperatures and increased atmospheric CO₂ concentrations are likely to favor ruderal species characterized by rapid phenological development and high dispersal capacity. Enhanced abiotic stressors—such as elevated temperatures, water scarcity, and increased UV-B radiation—are expected to affect crops more severely than weeds, given the latter’s greater evolutionary potential to develop stress-tolerant biotypes. Moreover, the increased frequency and intensity of extreme events (e.g., drought, flooding, and soil salinization) may reduce weed community diversity, potentially leading to dominance by a limited number of highly competitive species and consequently intensifying reliance on chemical weed control. Simplification of weed communities may also increase vulnerability to the introduction and establishment of alien species, particularly those originating from hot and arid regions, some of which may be parasitic, toxic, or allergenic. Climate change-induced phenological mismatches between flowering plants and pollinators are likely to favor wind-pollinated weed species, further compromising the aesthetic and ecological quality of agricultural landscapes. Additionally, increased production of wind-dispersed allergenic pollen, together with the anticipated rise in herbicide applications, may pose significant risks to human health. An effective agronomic strategy to address future weed scenarios should include the genetic improvement in crops to enhance adaptive plasticity, exploiting germplasm from ancestral lines and related wild species. Full article

Understanding how pollinators adjust their behavior to maximize reproductive success in resource-limited desert ecosystems is a fundamental ecological question. In this study, we investigated X. mongolicus using a combination of field behavioral observations, pollen identification, nutritional analysis, and morphometric measurements to systematically examine interannual variations in its flower visitation spectrum, foraging behavior, bee bread composition, and offspring body size. Our findings reveal a striking contrast: although this species exhibits polyphagy in flower visitation, it shows dietary specialization in larval nutrition—over 92% of the pollen in its bee bread originates from just two leguminous species, A. mongolicus and O. bicolor. Foraging duration increased with rising temperature and humidity, and bees adapted to strong winds by flying close to the ground. Compared with 2024, the bee bread in 2025 had lower fresh weight but higher crude protein content, and offspring body size was larger—likely due to more abundant spring rainfall in 2025, which improved the flowering performance of A. mongolicus. Collectively, these results indicate that this bee species copes with resource uncertainty in desert habitats through flexible foraging range and highly specialized food storage, with its reproductive success closely tied to the nutritional supply of key plants and precipitation patterns. This study highlights the role of precipitation timing in shaping the nutritional foundation of plant–pollinator interactions, providing a scientific basis for the conservation and management of desert pollinators. Full article

Range limits are often hypothesized to arise from reduced reproductive success at distributional margins, yet direct tests integrating pollination and post-pollination processes remain uncommon. Whether reproductive failure constrains the distylous Gelsemium sempervirens at its western range edge in eastern Texas was investigated by quantifying flowering phenology, floral visitation, pollinator effectiveness, and seed fate over two flowering seasons. Flowering timing differed markedly between years due to freeze events, but flowering effort and morph synchrony remained high. Although multiple floral visitors were recorded, fruit set was overwhelmingly associated with the southeastern blueberry bee (Habropoda laboriosa), which dominated visitation and remained active throughout the flowering period. No evidence of autonomous self-pollination or breakdown of functional distyly was detected. Seed set in unattacked fruits was high and comparable to values reported from central-range populations. In contrast, post-pollination seed loss due to cryptic fruit herbivory substantially reduced seed survival, though herbivory patterns did not differ qualitatively from those documented elsewhere in the species’ range. Together, these results indicate that reproductive failure does not explain the abrupt western range limit of G. sempervirens and instead suggest that ecological transitions associated with the forest–prairie ecotone, rather than pollination or early seed development, may play a more important role in shaping the species’ distribution. Full article

The endemic Minuartia nifensis, the only known gynodioecious species of its genus, offers a suitable model for understanding the relationships between floral characteristics, pollination, and mating systems in species with narrow distributions and single populations. We analyzed population structure, floral morphology, pollen viability, stigma receptivity, mating system components, and pollinator assemblages using field observations, morphometric measurements, controlled pollination experiments (autogamy, allogamy, apomixis and open pollination), and standardized pollinator surveys. The population exhibited an approximately balanced hermaphrodite–female ratio (0.97:1) and clear sexual dimorphism, with hermaphrodite flowers significantly larger than female flowers. Despite this dimorphism, pollinator visitation was similar between morphs, with 52.54% of visits to hermaphrodite flowers and 47.46% to female flowers. A total of 1734 visits by seven visitor species were recorded, of which approximately 95% of potentially effective pollen transfer was attributable to three bee taxa. Pollen viability, stigma receptivity, and visitation frequency peaked between 12:00 and 14:00, accounting for 58% of total insect visits. Controlled pollination experiments showed highest reproductive success under cross-pollination and limited success under self-pollination, indicating a mixed but predominantly outcrossing mating system. Together, these results suggest that gynodioecy in M. nifensis may be supported by floral differentiation, temporal reproductive traits, and pollinator-mediated pollen transfer. Full article

Managed colonies of the Western honey bee, Apis mellifera, are essential to global food security by ensuring the pollination of a wide array of crops that are crucial for human consumption. However, substantial declines in managed honey bee populations have been reported worldwide, including in Australia, the United States and Europe. These losses have been attributed to the multifaceted interplay of stressors encompassing agrochemical impact, climate fluctuations, pathogens, suboptimal forage conditions, and habitat reduction. In particular, Paenibacillus larvae, the causative agent of American foulbrood (AFB), is one of the most destructive bacterial pathogens for honey bees due to its high transmissibility, environmental persistence, and capacity to cause complete colony collapse. Recurrent and widespread AFB outbreaks impose significant economic and biosecurity burdens on apiarists, exacerbating declines in pollination services and agricultural productivity. This review synthesises the current landscape of therapeutic strategies targeting AFB, including bacteriophage-based approaches, vaccine development, probiotics, and essential oils, and evaluate their reported field applications, efficacy, and practical limitations. Bacteriophages and immune-priming approaches show the greatest potential to reduce larval mortality and pathogen load, although their application is constrained by formulation stability, delivery challenges, and limited large-scale field validation. Probiotics and essential oils produce highly variable and inconsistent effectiveness under field conditions. Overall, these alternatives currently represent promising complementary tools rather than standalone treatments, underscoring the need for further investigation. Full article

Agricultural intensification and the widespread use of pesticides have exerted long-term pressures on honey bees, negatively affecting their survival, abundance, and immunity. Understanding the perceptions of beekeepers and farmers is essential to identify collaborative actions and assess whether existing regulations provide adequate protection for bee health. Laws and regulations play a crucial role in managing apicultural health risks; however, their effectiveness depends on how well they align with ecological realities and policy objectives. This study investigates whether Chile’s regulatory frameworks provide sufficient protection for honey bees by identifying key gaps and opportunities, particularly regarding pesticide use in agriculture. A mixed-methods analysis was applied to a sample of beekeepers from southern Chile—considering variables such as gender, education level, and regulatory awareness—and complemented with a review of legal documents and semi-structured interviews with key stakeholders. Findings show that although Law No. 21,489 represents an important step toward formalizing beekeeping and reducing pesticide-related risks, its scope remains limited by weak enforcement capacity, scarce institutional resources, and insufficient regulation of systemic pesticides. Strengthening environmental governance and updating the regulatory framework through greater inter-institutional coordination, beekeeper participation, and effective control mechanisms are essential to reconcile agricultural production with pollinator conservation and ecosystem sustainability. Full article

Bats (Chiroptera) provide critical ecosystem services, including pest suppression, pollination, and seed dispersal. Understanding their dietary ecology is essential for conservation management yet has historically been constrained by methodological limitations. This review synthesizes advances in bat dietary analysis over the past several decades, from traditional morphological and stable isotope approaches to the revolutionary DNA metabarcoding techniques that now dominate the field. We systematically evaluate the strengths and limitations of each methodological approach and examine how molecular methods have transformed our understanding of bat trophic ecology. Research progress across major feeding guilds—insectivorous, frugivorous, nectarivorous, carnivorous, and sanguivorous bats—is examined, with emphasis on recent discoveries enabled by molecular techniques. We discuss ecological and conservation applications, including ecosystem service quantification, food web construction, and responses to environmental change. Finally, we identify priority directions for future research, including long-read sequencing technologies, multi-method integration, reference database expansion, and One Health applications. This synthesis provides guidance for researchers selecting appropriate analytical approaches and highlights the critical role of dietary studies in bat conservation amid accelerating global change. Full article

The jujube (Ziziphus jujuba Mill.) is a significant economic fruit tree, valued for its nutritional and medicinal properties. However, advances in functional genomics are hindered by the lack of an efficient transformation system. To overcome the limitations of conventional explant, we established a fruit-pulp-derived, callus-based Agrobacterium-mediated transformation system using fruit-pulp harvested 50 days after pollination. Through orthogonal experimental design, 6-benzylaminopurine and 2,4-dichlorophenoxyacetic acid were identified as key regulators for inducing high-quality, friable callus in two jujube genotypes, ‘JZ60’ and ‘LWCZ’. This system revealed significant genotype-specific variation in auxin requirements for callus proliferation and in differential antibiotic sensitivity. Transformation efficiency, as evaluated by fluorescence screening, was primarily determined by acetosyringone concentration and the binary vector architecture. The results revealed that the compact pCY (kanamycin resistance) vector achieved higher transformation efficiency (up to 77.8%) than pCAMBIA1301, whereas the pCAMBIA1301 (hygromycin resistance) vector enabled more uniform transgene expression. Integration and expression of the ZjCBF3 transgene were confirmed by polymerase chain reaction (PCR), reverse transcription quantitative PCR, and green fluorescent protein fluorescence assays. This study established a fruit-pulp-based callus transformation system for jujube, providing a rapid platform for its functional genomic studies. Full article

Pitaya (Selenicereus spp.) cultivation has expanded in the Iberian Peninsula in recent years, driven mainly by increasing demand from the European market and by the crop’s good adaptability to Mediterranean conditions. However, the successful consolidation of this crop requires the adoption of cultural practices adapted to regional edaphoclimatic conditions and production systems. The present review aims to synthesise and critically analyse the scientific literature on pitaya cultural practices, integrating information from major producing regions worldwide and from Mediterranean environments, where data remain limited. Key topics include propagation methods for success in early development, training systems and pruning, soil management within the framework of sustainable orchard management practices and the crop’s versatility in integrating diverse agroecosystems. In addition, bibliometric analysis identified water requirements and irrigation strategies as key aspects for which region-specific guidelines are still required. This study emphasises the utilisation of floral induction techniques and the significance of supplementary manual pollination for ensuring higher productivity and superior fruit quality. Overall, this review provides a consolidated reference to support the development of sustainable and regionally adapted pitaya production systems in the Iberian Peninsula. Full article

Self-incompatibility (SI) is a key reproductive mechanism in angiosperms that prevents self-fertilization and promotes genetic diversity while limiting breeding efficiency. Akebia trifoliata is a recently domesticated economic crop native to East Asia with medicinal, edible, and oil-producing value. However, its late-acting self-incompatibility (LSI) severely limits genetic improvement and commercial development. To investigate the molecular basis of LSI, we conducted comparative transcriptomic analyses of pistils at 48, 96, 144, 192, and 240 h after self- and cross-pollination, identifying 1552, 2954, 1302, 814, and 1978 differentially expressed genes (DEGs), respectively. DEGs were consistently enriched in mitogen-activated protein kinase (MAPK) signaling, plant hormone signal transduction, and ubiquitin-mediated proteolysis pathways, with clear transcriptional differences before and after 96 h. Compared with cross-pollinated pistils, self-pollinated pistils showed restricted pollen tube spread, and genes related to pollen recognition and tube development showed differential expression at 48 and 96 h, indicating that LSI probably occurs within the pollen tube. Collectively, these results indicate that pistils of A. trifoliata exhibit distinct early responses to self- and cross-pollination, and that DEG-enriched pathways are similar to those involved in S-RNase-mediated SI. These results provide new insights into the molecular basis of LSI and suggest potential targets for overcoming the SI barrier. Full article

This study provides an updated overview of Anthophila (wild bees and honey bees) diversity and conservation status in Algeria, explicitly distinguishing between the managed honey bee (Apis mellifera) and native wild Anthophila species. Using a systematic PRISMA-based literature analysis, more than 179 bee species have been documented across Mediterranean and semi-arid ecosystems, confirming their irreplaceable contribution to ecosystem resilience and crop pollination and beekeeping systems. The majority of Algeria’s Anthophila diversity is represented by endemic and native wild bees that sustain natural ecosystems. However, they are under growing human-caused (anthropogenic) pressures in the Anthropocene, including pressure from habitat loss and fragmentation, agricultural intensification, widespread pesticide use, and climate change. In addition, pathogenic threats such as Varroa destructor, Nosema, and associated viruses are well documented in honey bees, while evidence for their presence and impact in wild bees in Algeria remains very limited. These stressors not only weaken specialist species but also accelerate biotic homogenization dominated by A. mellifera. Recent genomic research on native honey bee populations has revealed adaptive signatures linked to immunity and social behavior, offering new opportunities for innovative conservation strategies based on molecular and genetic tools. Such insights highlight the value of preserving local strains, which may hold key traits for resilience under changing environmental conditions. To safeguard Anthophila biodiversity, this study underscores the urgent need for Algeria to implement proven conservation strategies, including habitat restoration initiatives and Anthophila-friendly farming approaches, which are common internationally but remain largely unaddressed at the national scale. By integrating cutting-edge genetic research, ecological restoration, and sustainable innovation, Algeria, with its diverse habitats and largely unexplored Anthophila fauna, holds considerable potential for advancing biodiversity conservation strategies that also support food security. However, this potential can only be realized through further in-depth research and comprehensive species inventories. Full article