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Large-scale production of Arbuscular Mycorrhizal Fungi (AMF) consortia is a crucial stride in harnessing their potential for sustainable agriculture and plant growth enhancement. However, establishing optimal production conditions is challenging due to their obligate nature, variability, lack of standardized protocols, and limited understanding of their specific requirements. Previous attempts to standardize Root Organ Cultures (ROC) for AMF overlooked challenges related to viable inoculum production for field applications. This current investigation reported, for the first time, the optimization of various factors during large-scale production of AMF using ROC. By optimizing factors like gelling agents, media preparation, medium-to-inoculum ratios, incubation conditions, age, harvesting method and drying temperatures, we achieved significant yields of viable propagules. The standardized protocol outlined in this study will greatly influence commercial-scale AMF production. These standardized protocols are poised to contribute to larger-scale AMF production worldwide, with the potential to support sustainable agriculture and ecosystem management., (© 2013-2023 The Journal of Biological Methods, All rights reserved.)

Background and Aims: Long distance dispersal (LDD) contributes to the replenishment and recovery of tropical seagrass habitats exposed to disturbance, such as cyclones and infrastructure development. However, our current knowledge regarding the physical attributes of seagrass fragments that influence LDD predominantly stems from temperate species and regions. The goal of this paper is to measure seagrass fragment density and viability in two tropical species, assessing various factors influencing their distribution., Methods: We measured the density and viability of floating seagrass fragments for two tropical seagrass species (Zostera muelleri and Halodule uninervis) in two coastal seagrass meadows in the central Great Barrier Reef World Heritage Area, Australia. We assessed the effect of wind speed, wind direction, seagrass growing/senescent season, seagrass meadow density, meadow location and dugong foraging intensity on fragment density. We also measured seagrass fragment structure and fragment viability; i.e., potential to establish into a new plant., Key Results: We found that seagrass meadow density, season, wind direction and wind speed influenced total fragment density, while season and wind speed influenced the density of viable fragments. Dugong foraging intensity did not influence fragment density. Our results indicate that wave action from winds combined with high seagrass meadow density increases seagrass fragment creation, and that more fragments are produced during the growing than the senescent season. Seagrass fragments classified as viable for Z. muelleri and H. uninervis had significantly more shoots and leaves than non-viable fragments. We collected 0.63 (±0.08 SE) floating viable fragments 100 m -2 in the growing season, and 0.13 (±0.03 SE) viable fragments 100 m -2 in the senescent season. Over a third (38%) of all fragments collected were viable., Conclusion: There is likely to be a large number of viable seagrass fragments available for long distance dispersal. This study's outputs can inform dispersal and connectivity models that are used to direct seagrass ecosystem management and conservation strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Bacterial communities associated with plant propagules remain understudied, despite the opportunities that propagules represent as dispersal vectors for bacteria to new sites. These communities may be the product of a combination of environmental influence and inheritance from parent to offspring. The relative role of these mechanisms could have significant implications for our understanding of plant-microbe interactions. We studied the correlates of microbiome community similarities across an invasion front of red mangroves (Rhizophora mangle L.) in Florida, where the species is expanding northward. We collected georeferenced propagule samples from 110 individuals of red mangroves across 11 populations in Florida and used 16S rRNA gene (iTag) sequencing to describe their bacterial communities. We found no core community of bacterial amplicon sequence variants (ASVs) across the Florida range of red mangroves, though there were some ASVs shared among individuals within most populations. Populations differed significantly as measured by Bray-Curtis dissimilarity, but not Unifrac distance. We generated data from 6 microsatellite loci from 60 individuals across 9 of the 11 populations. Geographic distance was correlated with beta diversity, but genetic distance was not. We conclude that red mangrove propagule bacterial communities are likely influenced more by local environmental acquisition than by inheritance., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Human activities and environment changes have changed river estuary ecosystems, which impacts element changes in coastal sediments and mangroves. Mangrove propagule chemical traits showed a systematic shift along environmental gradients. But knowledge about how the pattern of multi-element variability is coordinated in propagule remains limited, and the conservation of macro and trace elements in propagules is also unknown. In this study, the concentrations, variability and coordinated pattern variation of 13 elements in Aegiceras corniculatum propagule across shrimp aquaculture effluent habitats, as well as the relationship between propagule element and environment factors were explored. We used CV to quantify the variability of each element, and then explore the pattern of multi-element variability. The results showed that: (1) in the habitats affected by shrimp aquaculture, the elements content shows: C > K > Cl > N > Na > P > S > Mg > Ca > Fe > Mn > Zn > Cu, and the coefficient variation shows: Mn > Cu > Fe > Zn > S > N > P > Cl > Na > K > Mg > Ca > C, which means that the element concentration are negatively correlated with the element variability and the variability of macro-elements was more conservative than micro-elements in these habitats; (2) pH, OM, C:P, and SiO 3 were the four important environmental factors explaining the A. corniculatum propagule variation. In conclusion, effluent from shrimp aquaculture does affect the coordinated pattern of multiple element variability in A. corniculatum propagules. These results provide a strong evidence for assessing the impact of shrimp aquaculture effluent discharges on mangrove and provide an important theoretical basis for mangrove conservation and restoration.2- were the four important environmental factors explaining the A. corniculatum propagule variation. In conclusion, effluent from shrimp aquaculture does affect the coordinated pattern of multiple element variability in A. corniculatum propagules. These results provide a strong evidence for assessing the impact of shrimp aquaculture effluent discharges on mangrove and provide an important theoretical basis for mangrove conservation and restoration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Agaricus bisporus var. bisporus, the button mushroom, has a predominantly pseudohomothallic life cycle. Most of its spores are heterokaryotic and give rise to fertile heterokaryons. However, previous studies have suggested that outcrossing should not be rare in wild populations. In order to discover how outcrossing occurs, we experimentally favored it between aerial propagules of a fruiting donor mycelium and a delayed receiver mycelium that only invaded culture trays. Two donor/receiver pairs were studied, and potentially hybrid basidiomata collected on the receiver trays were analyzed with a mitochondrial marker, two unlinked nuclear CAPS markers, then haplotype markers based on DNA sequences obtained after PCR cloning of the rDNA ITS region and the fruk gene. For one of the two pairs, most basidiomata were hybrids between the donor and the receiver. Genotyping of the hybrids revealed only two genotypes consistent with outcrossing involving airborne mycelium fragments rather than basidiospores. The resident receiver heterokaryon that provided its mitochondria to the hybrid basidiomata is suspected to have had a trophic contribution to their growth and successful fruiting. The high level of heterozygosity and the cultivar introgression previously revealed in wild populations of this pseudohomothallic species may result from outcrossing involving airborne pieces of mycelium.

Key Message: Melatonin plays a crucial role in the mitigation of plant biotic stress through induced defense responses and pathogen attenuation. Utilizing the current knowledge of signaling and associated mechanism of this phytoprotectant will be invaluable in sustainable plant disease management. Biotic stress in plants involves complex regulatory networks of various sensory and signaling molecules. In this context, the polyfunctional, ubiquitous-signaling molecule melatonin has shown a regulatory role in biotic stress mitigation in plants. The present review conceptualized the current knowledge concerning the melatonin-mediated activation of the defense signaling network that leads to the resistant or tolerant phenotype of the infected plants. Fundamentals of signaling networks involved in melatonin-induced reactive oxygen species (ROS) or reactive nitrogen species (RNS) scavenging through enzymatic and non-enzymatic antioxidants have also been discussed. Increasing evidence has suggested that melatonin acts upstream of mitogen-activated proteinase kinases in activation of defense-related genes and heat shock proteins that provide immunity against pathogen attack. Besides, the direct application of melatonin on virulent fungi and bacteria showed disrupted spore morphology, destabilization of cell ultrastructure, reduced biofilm formation, and enhanced mortality that led to attenuate disease symptoms on melatonin-treated plants. The transcriptome analysis has revealed the down-regulation of pathogenicity genes, metabolism-related genes, and up-regulation of fungicide susceptibility genes in melatonin-treated pathogens. The activation of melatonin-mediated systemic acquired resistance (SAR) through cross-talk with salicylic acid (SA), jasmonic acid (JA) has been essential for viral disease management. The high endogenous melatonin concentration has also been correlated with the up-regulation of genes involved in pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity (ETI). The present review highlights the versatile functions of melatonin towards direct inhibition of pathogen propagule along with active participation in mediating oxidative burst and simulating PTI, ETI and SAR responses. The hormonal cross-talk involving melatonin mediated biotic stress tolerance through defense signaling network suggests its suitability in a sustainable plant protection system., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Control of invasive species relies partly on permanent surveillance at international points of entry. We report the exceptional trapping of one adult mosquito (Diptera: Culicidae) in the port of Marseille, France, in July 2018, during a routine survey conducted according to International Health Regulations. Morphological and molecular identification classified the specimen as a female Aedes (Stegomyia) aegypti (L.), vector of many arboviruses, absent from Europe and the Mediterranean rim since the 1950s. A world reference panel of approximately 23,000 genome-wide single nucleotide polymorphisms determined that the mosquito originated from Cameroon, west Africa. Cross-reference of this geographic location with boats traveling from Central Africa to Marseille during the trapping period suggests that the mosquito travelled within an identified merchant ship, a vehicles carrier connecting Douala, Cameroon to Marseille, France. This ship left Douala on June 25, 2018 and arrived 20 days later in Marseille on July 15. The mosquito was captured 350 m away from the dock. The interception of a propagule of an invasive species is a rare event that must be considered a priority to prevent its successful establishment., (© C. Jeannin et al., published by EDP Sciences, 2022.)

Dispersal is a critical ecological process that modulates gene flow and contributes to the maintenance of genetic and taxonomic diversity within ecosystems. Despite an increasing global understanding of the arbuscular mycorrhizal (AM) fungal diversity, distribution and prevalence in different biomes, we have largely ignored the main dispersal mechanisms of these organisms. To provide a geographical and scientific overview of the available data, we systematically searched for the direct evidence on the AM fungal dispersal agents (abiotic and biotic) and different propagule types (i.e. spores, extraradical hyphae or colonized root fragments). We show that the available data (37 articles) on AM fungal dispersal originates mostly from North America, from temperate ecosystems, from biotic dispersal agents (small mammals) and AM fungal spores as propagule type. Much lesser evidence exists from South American, Asian and African tropical systems and other dispersers such as large-bodied birds and mammals and non-spore propagule types. We did not find strong evidence that spore size varies across dispersal agents, but wind and large animals seem to be more efficient dispersers. However, the data is still too scarce to draw firm conclusions from this finding. We further discuss and propose critical research questions and potential approaches to advance the understanding of the ecology of AM fungi dispersal.

In this overview, the authors have discussed the potential advantages of the association between mycorrhizae and plants, their mutual accelerated growth under favorable conditions and their role in nutrient supply. In addition, methods for isolating mycorrhizae are described and spore morphologies and their adaptation to various conditions are outlined. Further, the significant participation of controlled greenhouses and other supported physiological environments in propagating mycorrhizae is detailed. The reviewed information supports the lack of host- and niche-specificity by arbuscular mycorrhizae, indicating that these fungi are suitable for use in a wide range of ecological conditions and with propagules for direct reintroduction. Regarding their prospective uses, the extensive growth of endomycorrhizal fungi suggests it is suited for poor-quality and low-fertility soils., Competing Interests: Conflict of interestOn behalf of all the authors, the corresponding author states that there is no conflict of interest., (© King Abdulaziz City for Science and Technology 2020.)

Revegetation of pioneer plants is a critical phase in community establishment for mudflats in seriously degraded coastal wetlands. We tested a hypothesis of the importance of a "power balance" among propagule resilience and sedimentary and tidal disturbances for vegetation reestablishment. Our experiment used three types of propagules (seeds, seedlings, and corms) of native Scirpus species in the fringing flats with similar tidal flows and varying sedimentary intensities in the Yangtze Estuary. Regardless of the initial planting densities, the seed germination rate was extremely low in the field situation. Although the incubated seedlings were planted directly on the bare flat, the wave movement easily flushed the seedlings, even at the site with moderate sedimentary accretion. Failure of the revegetation practice using the seed and seedling materials indicated that the combined "growing and anchoring power" of young seedlings and "stabilizing power" of the sediment were insufficient to withstand the "dislodging power" of the tidal energy. In contrast, the planting approach with underground propagules (corms) proved to be feasible for vegetation establishment at the sites with moderate and low-level sedimentary intensities. The successful practice improved the tipping point of plant survival and tussock formation could be surpassed when the combined growing and anchoring power of seedlings that developed from corms with the stabilizing power of the sediment was greater than the dislodging power of the wave energy. However, at the site with high-level sedimentary intensity, the excessive sediment converted to the burying stress power as seedlings developed from the corms, revealing a burial threshold for seedling survival. The risk of seedling establishment was high when the burying stress power of the sediment far outweighed the combination of the growing power of the seedlings and the sediment removal power of the tidal current and surpassed the tipping point of vegetation die-off. Additionally, we checked the practice cost of the different approaches to ensure a highly cost-effective revegetation planning based on site suitability. This study highlights that understanding of the propagule-sediment-tide power balance offers a tool for improvement of the revegetation and management of site-specific sedimentary and hydrological environments for many degraded coastal ecosystems., (© 2019 by the Ecological Society of America.)

Premise of the Study: Mosses produce asexual propagules, which are dispersed, thus allowing population establishment and maintenance. However, it is unknown if or how protonemata-one of their asexually produced propagules-are dispersed. Moss protonemata were exposed to three dispersal vectors (water, wind, and snails) to describe the dispersal capability and survival after dispersal., Methods: The protonemata of mosses Callicostella belangeriana and Taxiphyllum taxirameum were splashed with water drops from a 1 or 2 m height, exposed to two wind velocities (V 1 = 2.74 mps and V 2 = 3.76 mps), and fed to terrestrial snails. Dispersal of protonemata was described for wind and water by studying the dispersal distance and the relationships between protonemata sizes and dispersal distances. Survival after dispersal was recorded for the three vectors., Key Results: Water and wind dispersed protonemata up to 80 and 265.5 cm, respectively. The protonemata dispersed the farthest distance when splashed by 2 m drops and hit by V 2 wind velocities. No, or little, relationship between protonemata size and dispersal distance was found for the water and wind vectors. Protonemata survived and became established after dispersal: survival was high when dispersed by water and snails, but was low for wind., Conclusions: For the first time, it was shown that protonemata are dispersed mostly close to the source, which is suggested to aid in moss population maintenance., (© 2018 Botanical Society of America.)

MicroRNA-like RNAs (milRNAs) are short non-coding regulatory sRNAs which play an important role in regulating gene expression at the post-transcriptional level by targeting mRNAs for degradation or inhibiting protein translation. To explore the presence of milRNAs in Fusarium oxysporum f. sp . niveum ( Fon ) and analyze their expression at different propagules, two categories of sRNAs were identified from Fon hyphae and microconidia using illumina sequencing. A total of 650,960 and 561,114 unique sRNAs were obtained from the hyphae and microconidia samples. With a previously constructed pipeline to search for microRNAs, 74 and 56 milRNA candidates were identified in hyphae and microconidia, respectively, based on the short hairpin structure analysis. Global expression analysis showed an extensively differential expression of sRNAs between the two propagules. Altogether, 78 significantly differently expressed milRNAs were identified in two libraries. Target prediction revealed two interesting genes involved in trichothecene production, necrosis and ethylene-inducing peptide 1 (NEP1) biosynthesis and in silico analysis indicated that they were down-regulated by Fon-miR7696a-3p and Fon-miR6108a. The expression levels of these two milRNAs were further validated by qRT-PCR and the results were consistent. The negative correlation of the expression levels between these two milRNAs and their potential target genes imply that they play a role in trichothecene and NEP1 biosynthesis. And this negative regulation for toxin-related gene expression is more specific in microconidia. The present study provides the first large-scale characterization of milRNAs in Fon and the comparison between hyphae and microconidia propagules gives an insight into how milRNAs are involve in toxin biosynthesis.

Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is supported by the comparatively pale colour of equally large, internally brooded eggs. Secondarily, geographic location drives the evolution of egg colour diversity, presumably through the selection of better-adapted, more costly pigments in response to ecological pressure., (© 2017 Elsevier Ltd. All rights reserved.)

Three mangroves species with differential propagule size, Avicennia marina (2.5±0.3cm), Bruguiera gymnorrhiza (16±2cm) and Rhizophora mucronata (36±3cm), were subjected to oil contamination. In a series of glasshouse and field experiments, the sediment, propagules, leaves and stems were oiled and growth monitored. Oiling of the propagules, leaves, internodes or sediment reduced plant height, leaf number, leaf chlorophyll content index and induced growth abnormalities, leaf abscission and mortality, with effects being greatest in A. marina, intermediate in R. mucronata and least in B. gymnorrhiza. The results suggest that the greater susceptibility of A. marina to oil is due to early shedding of the protective pericarp and rapid root and shoot development after detachment from the parent tree and not to propagule size. After seedling emergence, micromorphological factors such as presence of trichomes, salt glands and thickness of protective barriers influence oil tolerance., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Genetic principles underlie recommendations to use local seed, but a paucity of information exists on the genetic distinction and ecological consequences of using different seed sources in restorations. We established a field experiment to test whether cultivars and local ecotypes of dominant prairie grasses were genetically distinct and differentially influenced ecosystem functioning. Whole plots were assigned to cultivar and local ecotype grass sources. Three subplots within each whole plot were seeded to unique pools of subordinate species. The cultivar of the increasingly dominant grass, Sorghastrum nutans, was genetically different than the local ecotype, but genetic diversity was similar between the two sources. There were no differences in aboveground net primary production, soil carbon accrual, and net nitrogen mineralization rate in soil between the grass sources. Comparable productivity of the grass sources among the species pools for four years shows functional equivalence in terms of biomass production. Subordinate species comprised over half the aboveground productivity, which may have diluted the potential for documented trait differences between the grass sources to influence ecosystem processes. Regionally developed cultivars may be a suitable alternative to local ecotypes for restoration in fragmented landscapes with limited gene flow between natural and restored prairie and negligible recruitment by seed.

A field study was conducted to evaluate the relative importance of factors affecting seedling establishment and survival on a mangrove-dominated island in Belize. An examination of spatial patterns of seedling relative densities in relation to reproductive adults and physico-chemical conditions provided correlative information on factors affecting mangrove regeneration patterns. Distance from reproductive adults explained 89-94% of the variation in relative density of Rhizophora mangle seedlings, whereas availability of resources (light and NH 4 ) explained 73-80% of variation in Avicennia germinans seedling relative density. Just after dispersal (December), 89% of the variation in Laguncularia racemosa seedling relative density was attributable to distance from reproductive adults, but 7 months later (July) 74% of the variation was explained by intensity of flooding- and salinity-related stresses. Survivorship (after 2.5 years) of propagules and seedlings of R. mangle and A. germinans transplanted to zones of contrasting physico-chemical conditions demonstrated that: (1) mortality was highest during the establishment phase and major causes were failure to strand before viability was lost, consumption by predators and desiccation; and (2) after establishment, differences in sensitivity to physicochemical stress factors such as flooding (A. germinans) and initial orientation of the seedling axis (R. mangle) exerted a further influence on seedling survival. The results indicate that seedling recruitment in these neotropical forests is strongly influenced by dispersal patterns, differential establishment abilities and effects of physico-chemical factors that vary with elevation and distance from the shoreline.