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Centaurea melitensis L., known commonly as Malta thistle, is an aggressive and invasive weed species native to the Mediterranean region. This species now occupies a diverse range of ecosystems and climate types across the globe, including the semi‐arid zone of New South Wales, Australia. This semi‐arid climate differs dramatically from its native Mediterranean climate, therefore, we aimed to identify if local adaptations in the seed ecology for C. melitensis have developed. Seeds were collected from mature C. melitensis at Nanya Station, located within the Scotia region of NSW, and then transported to Federation University Australia, Mt. Helen, Victoria. Under laboratory conditions, mature seeds were tested for their germination responses to temperature (17/7, 25/15, 30/20, 35/25°C), photoperiod (12 h light and 12 h dark [L/D], 24 h dark [D]), salinity (0, 25, 50, 100, 150, 200, and 250 mM), osmotic potential (0, −0.1, −0.2, −0.4, −0.6, and −0.8 MPa), and pH (5, 6, 6.2, 7, 8, 9, and 10). The seeds achieved 100% germination in the 17/7°C treatment, with light not being a limiting factor. The seeds exposed to the 25/15°C (D) and 30/20°C (D) treatments also maintained high germination percentage, whilst germination was significantly reduced in the 35/25°C (D) treatment. The L/D photoperiod maintained a 77.5% germination rate at 35/25°C. Whilst increased salinity reduced seed germination from 97.5% in the control to 6% at 250 mM, this species nevertheless demonstrated resistance to osmotic stress with 23% germination observed at 0.8 MPa. Germination exceeded 90% at all of the soil pH treatments, although mean germination time was significantly reduced when seeds were treated with a solution of pH 10. Our results demonstrate that the C. melitensis seeds collected in Australia's semi‐arid zone demonstrated high germination plasticity and are capable of competitive germination in warmer and drier conditions compared to its native Mediterranean climate. Therefore, management efforts that prioritise restricting the spread of C. melitensis seeds into new environments, for example through practising correct sanitation protocols, coupled with the early detection and control of emerging populations will be critical for C. melitensis management in Australia. [ABSTRACT FROM AUTHOR]

Urban riparian vegetation is frequently dominated by invasive weeds, whose growth is often attributed to the elevated nitrogen and phosphorous in urban waters and soils. However, less recognition is given to other urban contaminants that may influence riparian vegetation. Previous studies have indicated that the dissolution of concrete modifies water and soil geochemistry and potentially enhances the growth of invasive species. This study investigated the relationship between urban water quality and the growth of an invasive urban riparian weed, willow (Salix spp.), to examine the contribution and influence of concrete materials. The study used water from endangered upland peat wetlands within and adjoining the Greater Blue Mountains World Heritage Area, many of which are in urban catchments and suffer degradation from water pollution and invasive weeds. In this study, willow cuttings were grown in a laboratory using four water treatments: pristine (non-urban), urban, and non-urban water exposed to two different concrete materials. The urban and concrete-exposed water treatments were associated with increased plant growth measures in addition to increased concentrations of barium and strontium that bioaccumulated in plant tissue. [ABSTRACT FROM AUTHOR]

Ramularia crupinae is a novel host-specific fungal pathogen of the invasive rangeland weed common crupina (Crupina vulgaris). The foliar and stem blighting pathogen was originally identified in France and has been approved by the United States Department of Agriculture–Animal and Plant Health Inspection Service as the first biological control agent for the management of common crupina in the western United States. In this study, a chromosome-level genome assembly of R. crupinae 00-010 was performed using PacBio sequencing technology. The assembly had a total size of 37.9 Mb distributed across 14 (telomere to telomere) chromosomes, with a GC content of 47.6%. The genome encoded 10,159 protein-coding genes with 890 predicted secreted proteins that comprised both unique and conserved canonical pathogen effectors. Genome comparisons with closely related pathogen species in the family Mycosphaerellaceae demonstrated family-wide orthologous effector groups and Ramularia-specific orthogroups. This new reference sequence is a valuable genomic tool that will assist in characterizing Ramularia–Crupina interactions and increase our understanding of Ramularia pathogenicity on both crops and weeds. [Figure: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.

The present study investigates the synergistic impact of earthworms (Eisenia fetida and Eudrilus eugeniae) and microbes during vermicomposting of invasive weed phytomass (Xanthium strumarium and Lantana camara). This study aims introducing an onsite solution for weed control while producing valuable organic manure. Vermitransformation and detailed characterization of mono- (VC1, VC2, VC4, VC5) and polyculture (VC3, VC6) of X. strumarium and L. camara has been reported for the first time employing E. fetida and E. eugeniae. The study achieved 45.16 ± 2.48–76.73 ± 1.37% vermiconvertion rate. The pH, conductivity, and concentration of heavy metals are effectively stabilized. Furthermore, it observed a significant reduction in total organic carbon (TOC) alongside the augmentation of nitrogen, phosphorus, potassium, calcium, and other trace elements (Zn, Ni, Fe). The ash content, humification index, and C/N ratio analysis established the maturity of the vermicompost. The macronutrient enhancement in the vermicompost samples was recorded 1.5- to 2.47-fold for total N, 1.19- to 1.48-fold in available P, 1.1- to 1.2-fold in total K, and 1.1- to 1.18-fold in total Ca. The germination index reveals a significant reduction in phytotoxicity, suggesting the production of mature and suitable vermicompost for agricultural use. Evaluating mono- and polyculture techniques, the research highlights the superiority of E. fetida over E. eugeniae. Further, the earthworm population and biomass have significantly increased by the end of 60-day experimental trial. [ABSTRACT FROM AUTHOR]

Rhododendron ponticum (L.) is a highly invasive, non-native woody shrub that prevents tree regeneration and kills native flora. Achieving successful control of rhododendron can be difficult due to its thick waxy leaf surfaces, which discourage the absorption of foliar-applied herbicides. The spray adjuvant Mixture B NF® has therefore been used for many years to improve the efficacy, absorption, and rainfastness of foliar applications of glyphosate. We established an experiment to test if alternative non-hazardous adjuvants could be equally effective. Treatments were applied as foliar sprays and then subjected to artificial rainfall to examine rainfastness. We found that the non-hazardous adjuvants Codacide Oil® and Toil® (both based on rapeseed oil), and also SU Wett®, offered little or no benefit to the efficacy or rainfastness of glyphosate applications to rhododendron. However, further research using these adjuvants on other weed species is recommended. The only treatment in our study that showed acceptable levels of rhododendron control was glyphosate plus Mixture B NF®. Current recommendations for the control of rhododendron are therefore still valid. When foliar sprays of rhododendron bushes are required, apply 2.88–3.60 kg a.i. ha− 1 glyphosate and add Mixture B NF® adjuvant at a rate of 2 per cent of final spray volume. A minimum rain-free period of 6 h should occur after application of glyphosate products to any weed type, but if there is a risk of rainfall occurring earlier than this, and the application cannot be delayed, the use of Mixture B NF® is likely to improve rainfastness, reduce run-off and improve control. [ABSTRACT FROM AUTHOR]

Abstract Invasive alien species are becoming more and more prevalent worldwide, Erigeron bonariensis and Bidens pilosa are two invasive species of Asteraceae in Egypt. To mitigate their detrimental effects and understand their differences in invasiveness, we compared the allelopathic potentials of E. bonariensis and B. pilosa using leachates, decaying residues, and volatilization processes. Notably, the allelopathic variances in leachates were significant, influenced by plant types, concentrations, and response patterns of target plant traits, as indicated by EC50. The relative phytotoxicity of the invasive species decayed residues peaked between 20 and 25 days in the soil, with a positive correlation with concentrations and soil properties. The highest quantities of phenolic acids were chlorogenic acid and caffeic acid reaching (5.41 and 4.39 µg g−1) E. bonariensis and (4.53 and 4.46 µg g−1) B. pilosa, in leachates extracts respectively, while in the soil extract of decayed residues were coumaric acid and ferulic acid measuring (1.66 and 1.67 µg g−1) E. bonariensis and (1.47 and 1.57 µg g−1) B. pilosa, respectively. Using GC/MS analysis, the main volatile components in E. bonariensis were 1, 8 cineole (5.62%), and α-terpinene (5.43%) and iso-Caryophyllene (5.2%) which showed the greatest inhibitory effects. While B. pilosa main constituents were trans-sabinene (5.39%) and Camphene (5.11%), respectively. Finally, the high invasion level displayed from E. bonariensis (0.221) compared with B. pilosa (0.094) which correlated with the stronger allelopathic activities against plant species, and soil properties. Therefore, the allelopathic potentialities of these species are critically relevant to their invasion success.

Invasive alien species are becoming more and more prevalent worldwide, Erigeron bonariensis and Bidens pilosa are two invasive species of Asteraceae in Egypt. To mitigate their detrimental effects and understand their differences in invasiveness, we compared the allelopathic potentials of E. bonariensis and B. pilosa using leachates, decaying residues, and volatilization processes. Notably, the allelopathic variances in leachates were significant, influenced by plant types, concentrations, and response patterns of target plant traits, as indicated by EC50. The relative phytotoxicity of the invasive species decayed residues peaked between 20 and 25 days in the soil, with a positive correlation with concentrations and soil properties. The highest quantities of phenolic acids were chlorogenic acid and caffeic acid reaching (5.41 and 4.39 µg g−1) E. bonariensis and (4.53 and 4.46 µg g−1) B. pilosa, in leachates extracts respectively, while in the soil extract of decayed residues were coumaric acid and ferulic acid measuring (1.66 and 1.67 µg g−1) E. bonariensis and (1.47 and 1.57 µg g−1) B. pilosa, respectively. Using GC/MS analysis, the main volatile components in E. bonariensis were 1, 8 cineole (5.62%), and α-terpinene (5.43%) and iso-Caryophyllene (5.2%) which showed the greatest inhibitory effects. While B. pilosa main constituents were trans-sabinene (5.39%) and Camphene (5.11%), respectively. Finally, the high invasion level displayed from E. bonariensis (0.221) compared with B. pilosa (0.094) which correlated with the stronger allelopathic activities against plant species, and soil properties. Therefore, the allelopathic potentialities of these species are critically relevant to their invasion success. [ABSTRACT FROM AUTHOR]

The role of microbial communities in the establishment of plant pathogens introduced to new environments as weed biocontrol agents is relatively unexplored. Substantial evidence from crop protection research shows how bulk microbial communities influence the establishment, survival, and success of pathogens. Just as mismatches between biocontrol agents, host genotypes, and climate can lead to establishment failure, we propose that mismatches between microbial biocontrol agents and resident microbiomes may be a cause of apparent weed biocontrol failures. From this perspective, we discuss recent progress in research on plant-associated microbial communities whose interactions influence disease development, or “pathobiomes,” and consider the implications for biocontrol agent evaluation and release. Open questions about how weed pathobiomes develop and influence agent success rates provide ample opportunity for researchers to adapt new methods and analytical frameworks that will enhance biocontrol programs. We conclude by prioritizing the development of standard methods to include microbiomes as a component of release studies. Developing a pathobiome-aware agent selection and release process will improve agent establishment rates and biocontrol outcomes.

Aquatic weeds have exceptionally high reproduction rates, are rich in cellulose and hemicellulose, and contain a negligible amount of lignin, making them an ideal crop for the next generation of biofuels. Previously reported studies proposed that water hyacinth, water lettuce, common duckweeds, and water spinach can be managed or utilized using different advanced techniques; from them, anaerobic digestion is one of the feasible and cost-effective techniques to manage these biowastes. The present study was carried out to investigate the potential of utilizing four common aquatic weed species (water hyacinth, water lettuce, common duckweeds, and water spinach) as substrates for anaerobic digestion in order to produce biogas for use in biofuels. The high reproduction rates and high cellulose and hemicellulose content, coupled with low lignin content, of these aquatic weeds make them ideal candidates for this purpose. The study evaluated the feasibility of using anaerobic digestion as a management technique for these aquatic weeds, which are often considered invasive and difficult to control. The results from various studies indicate that these aquatic weeds are productive feedstock options for anaerobic digestion, yielding a high biogas output. Among the aquatic weeds studied, water hyacinth, water lettuce, and common duckweeds exhibit higher methane production compared to water spinach. The study provides an overview of the characteristics and management strategies of these aquatic weeds in relation to biogas production, with possible future developments in the field. [ABSTRACT FROM AUTHOR]

The success of invasive plants can be better understood by comparing their traits with closely related native species. This study compared germination ecology and seedling growth of invasive Ageratum houstonianum and Ageratum conyzoides with co‐occurring and allied native Adenostemma lavenia. Seeds were germinated under a different light (12 h photoperiod/complete dark), temperatures (low: 25°C/15°C day/night, and high: 30°C/20°C), and different levels of water stress (−0.1, −0.25, −0.5, −0.75, and −1 MPa). Seedlings were grown to determine biomass allocation, relative growth rate (RGR), plant height, and number of leaves. The seed mass and size of native A. lavenia were higher than those of invasive species. Seeds of all species were positively photoblastic. At low temperature and in all levels of water stress, all measured parameters except mean germination time were the highest in A. houstonianum. However, at high temperature, there was no significant difference in germination percentage between A. houstonianum and A. lavenia. No germination of A. conyzoides and A. lavenia was recorded beyond −0.5 MPa water potential, but seeds of A. houstonianum germinated up to −0.75 MPa. A. houstonianum had higher root mass fraction, root‐to‐shoot ratio, and number of leaves than the other two species. Stem mass fraction and the height of seedling were highest in A. conyzoides. The RGR was 1.6 times higher in invasive Ageratum species than the native species; it was slightly higher in A. houstonianum than in A. conyzoides. Overall, the results suggest that germination traits and seedling growth performance can be used as predictors of a species' invasiveness. [ABSTRACT FROM AUTHOR]

Alternanthera tenella Colla and Euphorbia heterophylla L (Wild Poinsettia) are noxious invasive weed which are found on wastelands, along roadsides and mainly in the vicinity of agricultural crop fields on fallow lands. The study was undertaken to evaluate the allelopathic potential of whole plant aqueous extract of A. tenella and aqueous leaf extracts of E. heterophylla on germination and seedling growth of Wheat (Triticum aestivum) from Dist. Pune, Maharashtra, India. Growth and germination parameters of seedlings were affected as concentration increased. Aqueous whole plant extracts of A. tenella showed 6% of seedling germination whereas E. heterophylla completely inhibited germination at higher concentration in T. aestivum. Root-shoot length and vigor index were significantly reduced from 25% concentration as compared to control (100%). Experiments were conducted in triplicates and under controlled laboratory conditions. It can be concluded that Euphorbia extracts exhibited more phytotoxic effects on growth and germination of T. aestivum than A. tenella. Phytochemical analyses of aqueous and methanolic extracts showed the presence of alkaloids, phenols, flavonoids, tannins, proteins while carbohydrates and saponins were absent in Euphorbia. Whereas, Alternanthera aqueous as well as methanolic extracts revealed the presence of similar phytochemicals as that of Wild Poinsettia. Saponins and phenols were absent in A. tenella. The allelopathic effects may be due to presence of phytochemicals present in the plant. [ABSTRACT FROM AUTHOR]

This study has put forth the concept of "control through utilization" for invasive weeds, which cause severe damage to ecosystem and biodiversity. The study comprised of extraction of lignin and pretreatment of spent biomass of four invasive weeds. Lignin was extracted from native biomass using 1,4–dioxane as solvent. Lignin yield of all biomass varied in the range 8.61 − 11.14% w/w with the solvent recovery of 75.56–78.88% v/v. Extracted lignin was characterized using FTIR, TGA, and GPC. Lignin from Mikania micrantha had the highest thermal stability (T50% = 490 °C) and molecular weight (Mw = 5537 g/mol). The spent biomass was subjected to dilute acid pretreatment for synthesis of total reducing sugars (TRS). TRS yields from different entities were as follows: non-extracted biomass = 94.18 − 221.81 mg/g, warm water wash = 8.74 − 15.66 mg/g, and raw biomass = 115.9 − 391.27 mg/g raw biomass. Biomass of Saccharum spontaneum gave the highest TRS yield. [ABSTRACT FROM AUTHOR]

Dam construction projects among the most extensive and most expensive projects are considered. It is always appropriate and optimal for such concrete structures to reduce the volume of concrete and consequently reduce construction costs is essential. In this study, invasive weed optimization software GNU octave, dimensions of concrete gravity dam Koyna located in India optimized stability constraints. For this purpose, a cross-section with a length unit consists of eight geometric parameters as input variables, and other geometric parameters were defined using these variables. The result showed that invasive weeds are well-optimized dimensions of the dam as the volume of concrete in the construction of the dam at the current level measures 3633 cubic meters that optimal dropped 3353 cubic meters, which is a mean of 7.7% of the value of the objective function (the volume of concrete in dams) is reduced. This amount of concrete decreased the construction of the dam, saving the cost and is more economical.

Weeds are considered the main reason for crop yield loss in the world. Weed control and management include various treatments such as cultural, physical, chemical, and biological methods. Chemical control of weeds is the most common method; however, the application of commercial synthetic herbicides caused several dangerous hazards in the environment including the appearance of resistant weed biotypes. Prosopis farcta (Banks & Sol.) J.F.Macbr. (Family: Fabaceae), is a common weed plant in the Middle East, where it is hard to eliminate due to its deep and overlapped roots. On the other side, it has many traditional uses around the world. Herein, the essential oil (EO) of P. farcta above-ground parts was extracted via hydrodistillation techniques and then analyzed using gas chromatography-mass spectroscopy (GC-MS). From the GC-MS analysis, 47 compounds were identified with a relative concentration of 98.02%, including terpenes as the main components (95.08%). From overall identified compounds, cubenol (19.07%), trans-chrysanthenyl acetate (17.69%), torreyol (8.28%), davana ether (3.50%), camphor (3.35%), and farnesyl acetone (3.13%) represented the abundant constituents. Furthermore, the phytotoxic activity of the P. farcta EO was assessed against the weed Dactyloctenium aegyptium (L.) Willd. The EO of P. farcta, at a concentration of 100 µL L−1, significantly inhibited the germination, seedling shoot growth, and seedling root growth by 64.1, 64.0, and 73.4%, respectively. The results exhibited that the seedling root growth is the most affected followed by the seed germination and seedling shoot growth with respective IC50 at 64.5, 80.5, and 92.9 µL L−1. It can be concluded that weeds are not absolutely harmful, but they may have beneficial uses, such as, for example as a source of phytochemicals with application in weed control practices (bioherbicides). It is advised to conduct additional research to characterize the allelopathic action of the major chemicals in their pure form, either alone or in combination, against a variety of weeds. [ABSTRACT FROM AUTHOR]

Plant–arbuscular mycorrhizal fungal (AMF) associations can mediate soil resources among competing plants to influence plant resource capture and fitness, making AMF a potential agent of plant coexistence. We assessed plant coexistence, via niche and fitness differences, using six plant species varying in their mycorrhizal status. We grew the species in 15 competitive pairs with or without AMF. Effects of AMF on coexistence were determined by parametrizing pair-wise Lotka–Volterra plant competition models. Responses of the six plant species to AMF were determined by comparing the shoot biomass of single plants grown in the absence of any competition with AMF to the shoot biomass without AMF. The inoculation with AMF reduced the fitness differences between competitors, but the degree of AMF-mediated coexistence depended on the identity of the competing plant species. A greater AMF response difference between competing plant species reduced niche overlap and increased coexistence. These results show that while AMF generally reduce fitness differences, the equalizing effect of AMF is not always strong enough to overcome a competitive imbalance due to niche overlap and thus does not always lead to coexistence. Instead, it is the intrinsic growth response of different plant species to AMF, which can predict reduced niche overlap that in turn leads to coexistence. This implies that mycorrhizal dependence is a plant strategy to reduce niche overlap with competitors, thus allowing for greater coexistence. [ABSTRACT FROM AUTHOR]

Many emerging invasive weeds display rapid adaptation against different stressful environments compared to their natives. Rapid adaptation and dispersal habits helped invasive populations have strong diversity within the population compared to their natives. Advances in molecular marker techniques may lead to an in-depth understanding of the genetic diversity of invasive weeds. The use of molecular techniques is rapidly growing, and their implications in invasive weed studies are considered powerful tools for genome purposes. Here, we review different approach used multi-omics by invasive weed studies to understand the functional structural and genomic changes in these species under different environmental fluctuations, particularly, to check the accessibility of advance-sequencing techniques used by researchers in genome sequence projects. In this review-based study, we also examine the importance and efficiency of different molecular techniques in identifying and characterizing different genes, associated markers, proteins, metabolites, and key metabolic pathways in invasive and native weeds. Use of these techniques could help weed scientists to further reduce the knowledge gaps in understanding invasive weeds traits. Although these techniques can provide robust insights about the molecular functioning, employing a single omics platform can rarely elucidate the gene-level regulation and the associated real-time expression of weedy traits due to the complex and overlapping nature of biological interactions. We conclude that different multi-omic techniques will provide long-term benefits in launching new genome projects to enhance the understanding of invasive weeds’ invasion process. [ABSTRACT FROM AUTHOR]

Identification of suitable habitat for invasive weeds and their projected infestation extent across different land use cover types under a changing climate is crucial for the broad management goals of prevention, detection, and rapid response. In this study, we adopted an ensemble approach of species distribution models to project potential habitat of the invasive annual grass, Ventenata dubia, within the Gallatin County and along its road corridors, in Montana, USA, under current and future climates. The model prediction of V. dubia habitat was excellent with an AUC value of > 0.90. The climate predictors with most influence on V. dubia occurrence were precipitation, potential evapo-transpiration, relative humidity, vapor pressure deficit, and solar radiation for growing season months. Under current climate, the model projected 243 and 1,371 km2 coverage of V. dubia along road corridors and the entire County, respectively. The projected coverage of V. dubia was greatest for road corridors (239% under RCP4.5 and 302% under RCP8.5) compared to that of Gallatin County (127% under RCP4.5 and 241% under RCP8.5). Among the land use cover types, the model projected greatest expansion of V. dubia across agriculture land with 425% and 484%, and grasslands with 278% and 442% under RCP4.5 and RCP8.5 respectively. Our modelling approach suggests that the changing climate will facilitate spread and establishment of non-native species in disturbed habitats. We conclude that V. dubia with a short history of invasion is expanding at an alarming rate and requires greater investment in detection and monitoring to prevent further expansion. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the role of mucilage in seed dispersal and germination of the two closely related invasive weed species, Lepidium campestre and Lepidium draba. The study investigated the staining patterns of mucilage and its effects on seed germination, water uptake, dehydration, adherence to sand particles and dispersal by wind, water and animals following standard protocols. The mucilaginous seeds of L. campestre had a higher pectin and cellulose content than L. draba. This difference has a significant effect on water uptake and retention. The mucilage increased water uptake in both species, with L. campestre seeds absorbing significantly more water (836% compared to 75% in L. draba). Remarkably, the mucilage of both species had very little effect on seed germination. Significantly, the seeds of L. draba readily germinated under dry conditions, suggesting that this species may have developed different germination strategies. In addition, the seeds and fruits of L. draba showed a higher potential for dispersal via water and wind, whereas those of L. campestre adhered to animals. Further, L. campestre seeds showed significantly stronger adherence to sand particles (1872%) compared to those of L. draba (445%). This suggests that L. campestre seeds are more likely to disperse locally and possibly adhere to animals or soil particles. Our results suggest that mucilage produce by the two invasive weed species results in different methods of dispersal, which may help explain differences in their distribution patterns. • Both Lepidium species produce mucilaginous seeds. • Mucilage enhances seed germination. • Lepidium draba is more drought-tolerant. • Lepidium draba is wind/water-dispersed, L. campestre is animal-dispersed. • Mucilage may influence species distribution. [ABSTRACT FROM AUTHOR]

Most Romanian power plants were built in a period when environmental impact of their operation was undervalued, and constraints related to environmental protection were relatively few. Location of power plants and fly ash dumps was chosen most often by arbitrary criteria, and never after the impact that it may have on the environment. Building fly ash dumps have an effect of destruction of soils not only on the surface equivalent to those of dumps but also of the contiguous lands. Old fly ash dumps are a major risk because of the dispersion of pollutants in water and soil by percolation and soil leaching, and because of the unwanted invasion of weeds that are adaptable to arid conditions of the dumps and then invade surrounding areas jeopardizing the surrounding crops. In attempting to install vegetation an old fly ash dumps, the area were invaded by two species of weeds that quickly overgrown the experimental parcel and the surroundings. The present study followed the invasion degree of fly ash dumps with weeds and aspects regarding their development and breeding in the new formed ecosystem.

Solanum elaeagnifolium Cav. is known to be one of the most invasive species worldwide. In this study, laboratory and greenhouse experiments were carried out to investigate the allelopathic properties of S. elaeagnifolium vegetative parts, root parts, fruit mucilage, and exudate extracts on plant communities and soil properties. In addition, the extract profiles of allelochemicals were quantified and their influence on soil properties and microorganisms was determined. Overall, the allelopathic performance of S. elaeagnifolium was established depending on the extract types, used concentrations, and target species. The doseresponse activity indicated that vegetative parts extract showed the greatest allelopathic potential followed by root parts extract. Subsequently, mucilage extract had a moderate inhibitory potential, while root exudates showed the least activity. The same trend with slight response was detected in soil properties of pH and EC properties. Polyphenols, in the range of 5.70–0.211 mg · g–1 and flavonols, in the range of 2.392–0.00 mg · g–1, were found in the analyzed samples extracted by ethyl acetate using LC-DAD-MS. The total phenol amount was 1.67 to 1.89 in the rhizosphere and 0.53 to 087 mg · g–1 in non-rhizosphere soils. Solanum elaeagnifolium exhibited a greater significant suppression of fungi count in both high and low-density areas than in rhizosphere bacteria. In conclusion, the strong and broadspectrum allelopathic potentials may enhance the ability of S. elaeagnifolium to impact seed germination and seedling growth of neighboring species. These biochemical weapons may play a critical role to facilitate their invasion and establishment in new agroecosystems.

Invasive weeds of the Asteraceae family are widespread in the world. Arbuscular mycorrhiza (AM) is one of the main factors contributing to the successful distribution of these species that is most clearly manifested in the subfamily Asteroideae. The benefits of plant-AMF symbiosis are most significant under unfavorable biotic and abiotic conditions. The specificity of the relationship between arbuscular mycorrhizal fungi (AMF) communities and plants and is determined at the presymbiotic stage. The AMF colonization level is higher in invasive species than in native ones, but AMF communities associated with Asteraceae invasive species are less diverse. AMF communities of Asteraceae invaders often include fewer common species (e.g., species belonging to Diversisporales). Invaders also reduce native AMF species richness in new areas. Arbuscular mycorrhizal fungi can form mycorrhizal networks that allow the redistribution of nutrients in plant communities. The most significant influence of AMF associated with invasive Asteraceae plants is seen in the formation of soil and rhizosphere microbiota, including the suppression of beneficial soil bacteria and fungi. This review could be useful in the development of practical recommendations for the use of AMF-based fertilizers. [ABSTRACT FROM AUTHOR]

Western ragweed (Ambrosia psilostachya) is an invasive species in spring‐sown crops that can also cause allergic rhinitis and asthma due to its allergenic pollen. In order to evaluate the chemical and mechanical control of western ragweed, two separate experiments were conducted in 2019 and 2020. Chemical treatments included non‐treated plots, the combination of glyphosate and 2,4‐D, glyphosate + ammonium sulfate, bentazon, imazethapyr + surfactant, picloram, 2,4‐D, and mechanical treatments included: once mowing at 3–4 leaf stage, once mowing before male flowers' emergence, once mowing early female flowering stage, two mowings at 3–4 leaf stage, two mowings before male flowers' emergence. Results of these studies indicated that in both years, picloram at 0.96 kg ai ha−1 and the combination of 2,4‐D and glyphosate at 1.23 + 0.72 kg ai ha−1 provided more than 90% control of western ragweed and reduced plant height, dry weight, and density. The application of imazethapyr and bentazon, respectively, at the rates of 0.1 and 0.96 kg ai ha−1 did not cause visual damage. The mowing shortly before flowering was the most effective mechanical treatment for western ragweed control. In order to the efficient management of the western ragweed, we suggest that the mowing treatments if appropriately timed and application of glyphosate plus 2, 4‐D at 1.23 + 0.72 kg ai ha−1, and picloram at 0.96 kg ai ha−1 can prevent western ragweed from spreading by suppressing growth and reducing seed production. [ABSTRACT FROM AUTHOR]

Food insecurity continues to affect more than two-thirds of the population in sub‐Saharan Africa (SSA), particularly those depending on rain-fed agriculture. Striga, a parasitic weed, has caused yield losses of cereal crops, immensely affecting smallholder farmers in SSA. Although earlier studies have established that Striga is a constraint to crop production, there is little information on the spatial extent of spread and infestation severity of the weed in some SSA countries like Malawi and Zambia. This study aimed to use remotely sensed vegetation phenological (n = 11), climatic (n = 3), and soil (n = 4) variables to develop a data-driven ecological niche model to estimate Striga (Striga asiatica) spatial distribution patterns over Malawi and Zambia, respectively. Vegetation phenological variables were calculated from 250-m enhanced vegetation index (EVI) timeline data, spanning 2013 to 2016. A multicollinearity test was performed on all 18 predictor variables using the variance inflation factor (VIF) and Pearson's correlation approach. From the initial 18 variables, 12 non-correlated predictor variables were selected to predict Striga risk zones over the two focus countries. The variable "start of the season" (start of the rainy season) showed the highest model relevance, contributing 26.8% and 37.9% to Striga risk models for Malawi and Zambia, respectively. This indicates that the crop planting date influences the occurrence and the level of Striga infestation. The resultant occurrence maps revealed interesting spatial patterns; while a very high Striga occurrence was predicted for central Malawi and eastern Zambia (mono-cultural maize growing areas), lower occurrence rates were found in the northern regions. Our study shows the possibilities of integrating various ecological factors with a better spatial and temporal resolution for operational and explicit monitoring of Striga-affected areas in SSA. The explicit identification of Striga "hotspot" areas is crucial for effectively informing intervention activities on the ground. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus L. is considered an obnoxious weed due to its rapid dispersal, fast multiplications, and agricultural and health hazards. In addition to its physio-molecular and phytotoxic allelochemical usage, this weed most probably uses endophytic flora as an additional line of defense to deal with stressful conditions and tolerate both biotic and abiotic stresses. The aim of this article is to report the diversity of endophytic flora (fungi and bacteria) in P. hysterophorus and their role in the stress mitigation (biotic and abiotic) of other important crops. Various endophytes were reported from P. hysterophorus and their roles in crops evaluated under biotic and abiotic stressed conditions. These endophytes have the potential to alleviate different stresses by improving crops/plants growth, development, biomass, and photosynthetic and other physiological traits. The beneficial role of the endophytes may be attributed to stress-modulating enzymes such as the antioxidants SOD, POD and APX and ACC deaminases. Additionally, the higher production of different classes of bioactive secondary metabolites, i.e., flavonoids, proline, and glutathione may also overcome tissue damage to plants under stressed conditions. Interestingly, a number of medicinally important phytochemicals such as anhydropseudo-phlegmcin-9, 10-quinone-3-amino-8-O methyl ether 'anhydropseudophlegmacin-9, 10-quinone-3-amino-8-O methyl ether were reported from the endophytic flora of P. hysterophorus. Moreover, various reports revealed that fungal and bacterial endophytes of P. hysterophorus enhance plant growth-promoting attributes and could be added to the consortium of biofertilizers. [ABSTRACT FROM AUTHOR]

Dam construction projects are considered among the most extensive and expensive projects. It is always appropriate and optimal for such concrete structures to reduce the volume of concrete and consequently reduce construction costs. In this study, invasive weed optimization software GNU octave was used to find the dimensions of the concrete gravity dam Koyna located in India optimized stability constraints. For this purpose, a cross-section with a length unit consisting of eight geometric parameters was used as input variables, and other geometric parameters were defined using these variables. The result showed that invasive weeds are well-optimized dimensions of the dam as the volume of concrete in the construction of the dam at the current level measures 3633 cubic meters that optimal dropped 3353 cubic meters, which is a mean of 7.7% of the value of the objective function (the volume of concrete in dams) is reduced. This amount of concrete decreased the construction of the dam, saving the cost and is more economical. [ABSTRACT FROM AUTHOR]

In the present study, field surveys were conducted to detect potential associational susceptibility of crop plants (potato, alfalfa and maize) caused by Canadian goldenrod, Solidago canadensis (L.), one of the most common invasive weeds in Central and Eastern Europe, via plant associated virus vectoring aphids. Assessments were made in two major agricultural land types: crops grown under high input vs. low-input (LIF) conditions, with and without fertilizers and pesticides. The two most frequent aphid species, found both on Canadian goldenrod and crop plants, were the leaf-curling plum aphid, Brachycaudus helichrysi Kaltenbach and the glasshouse-potato aphid, Aulacorthum solani (Kaltenbach). Plant viruses in both weed and crop plants were identified using high-throughput sequencing of small RNAs. Peroxidase (POD) enzyme activity was tested in weed and crop plants to connect aphids feeding processes in weeds and crops. In addition, conceptual modeling was used to detect direct relationships between viruses and other crops. The Canadian goldenrod density was only relevant in the LIF regime. Furthermore, its association with B. helichrysi and associational susceptibility was detected only in LIF. In total, 18 viruses comprising 17 plant and one insect virus were detected in Canadian goldenrod, of which 11 were also detected in potato and alfalfa crops. POD activity was high and correlated with high aphid density in both weed and crop plants, suggesting a direct associational susceptibility between these plants through aphid infestation and viral transmission.

Populations of invasive alien plants create disruptive plant communities that are extremely adaptable, imposing severe ecological impacts on agriculture, biodiversity and human activities. To minimise these impacts, prevention and effective weed management strategies are urgently required, including the identification of satellite populations before they invade new areas. This is a critical element that allows weed management practices to become both successful and cost-effective. Mimosa pigra L. (Giant sensitive plant) is an invasive weed that has spread across various environments around the world and is considered one of the world's top 100 most invasive plant species. Being adaptable to a wide range of soil types, in addition to its woody protective prickles and low palatability, M. pigra has quickly spread and established itself in a range of habitats. Current control methods of this species include biological, chemical and physical methods, together with attempts of integrated application. Reports suggest that integrated management appears to be the most effective means of controlling M. pigra since the use of any single method has not yet proved suitable. In this regard, this review synthesises and explores the available global literature and current research gaps relating to the biology, distribution, impacts and management of M. pigra. The contribution of this work will help guide land managers to design appropriate and sustainable management programs to control M. pigra. [ABSTRACT FROM AUTHOR]

Soil salinity represents one of the most restrictive environmental factors for agriculture worldwide. In the present study, the salt tolerance of two weeds of the genus Amaranthus, A. albus and A. hybridus, the latter cultivated as green vegetable in Africa, were analysed. Both species showed a remarkable salt tolerance phenotype during germination and vegetative growth. To evaluate the percentage and rate of germination, seeds were germinated in Petri dishes in a germination chamber under increasing concentrations up to 300 mM NaCl. Higher concentrations of salt ranging from 150 to 600 mM NaCl were applied for one month to plants grown in individual pots in the greenhouse. All seeds of A. albus germinated in the control and almost half of the seeds under 200 mM NaCl, but only 4% of the seeds under 250 mM NaCl. In A. hybridus, germination was considerably lower in all treatments and was completely prevented at 250 mM NaCl. The plant growth of both species was severely affected by high salt concentrations of 450 and 600 mM NaCl, but not under lower concentrations. At this stage of the biological cycle, A. hybridus showed a higher salt tolerance, as indicated by the smaller reduction in its growth parameters. The dry weight of leaves and roots of plants receiving 600 mM NaCl decreased in comparison to control: less than 60% in A. hybridus but more than 70% in A. albus. The salt tolerance of the two species contributes to their invasive potential, but on the other hand represents a useful trait when considering them as potential crops for the future. [ABSTRACT FROM AUTHOR]

Invasive plants cause a global loss of biodiversity, pose a major threat to the environment and economy, and also significantly affect agricultural production and food security. Plant growth regulators (PGRs) are widely used in agricultural production and might also affect invasive weeds distributed around crops in various ways. At present, there are few studies concerning whether there are significant effects of PGRs on invasive weeds. In this study, two widely used PGRs in paddy fields, gibberellic acid (GA) and paclobutrazol (PAC), were applied on Oryza sativa and a noxious weed Alternanthera philoxeroides, which is frequently distributed in paddy fields. The purpose of this study was to investigate if there are different responses of rice and weeds to these two plant regulators and the significant effects of PGRs on invasive weeds. The results showed that GA significantly promotes the total biomass of A. philoxeroides by 52.00%, but does not significantly affect that of O. sativa. GA significantly increases the growth of aboveground and belowground A. philoxeroides, but not that of O. sativa. On the other hand, PAC extremely inhibited the aboveground and belowground biomass of A. philoxeroides by more than 90%, but did not significantly inhibit the belowground biomass of O. sativa. PAC also enhanced the leaf nitrogen content and chlorophyll content of A. philoxeroides, but not the traits of O. sativa. Therefore, the effects of PGRs are significantly different between rice and the invasive weed. The potential promotion effects of PGRs on weeds that are frequently distributed in farmland warrant sufficient attention. This is probably one of the important reasons why invasive weeds can successfully invade the agricultural ecosystem with large human disturbance. This study might sound an alarm for weed control in paddy fields. [ABSTRACT FROM AUTHOR]

The work was carried out with the objective of determining the spatial and temporal distribution of Albizia procera (Roxb.) Benth species in sugarcane areas in Cuba. For this purpose, the information contained in the database generated by the weed identification surveys carried out in the period 2016-2020 by the Integral Weed Control Service (SERCIM) of the Instituto de Investigaciones de la Caña de Azúcar (INICA) was used. The surveys were conducted by the visual method, walking the field along its diagonals, with the use of manuals or catalogs in digital or printed format. The magnitude of the infestation was evaluated through the frequency and area infested. The results showed that in the period 2016-2020 the species presented frequency values in the Accidental category, with an increasing trend. The highest frequency was found in the western region and the largest plagued area in the central region. The surveys evidenced the presence of this species in all stages of development and harvest cycles of sugarcane. It is recommended that a management strategy be developed to help reduce infested areas. [ABSTRACT FROM AUTHOR]

Solidago canadensis is an invasive weed that grows successfully under adverse environmental conditions and shows a high capability to various habits. To evaluate the role of local adaptation in the invasion of S. canadensis into heterogeneous environments, the morphological and physiological traits of S. canadensis plants were studied under salt (control, 100 and 150 mM NaCl), drought stress conditions (control, 75 and 100 g L-1 PEG-6000) and abscisic acid (ABA) (0, 25, and 50 ul L-1) application. Salt treatments significantly reduced the plant height, shoot dry weight (SDW), water use efficiency (WUE), intracellular CO2, and net photosynthetic rate (NPR) by 8.17, 28.75, 21.65, 20.71 and 35.44%, respectively than control plants. Among salt treatments, maximum reduction was found under 150 mM NaCl followed by 100 mM NaCl and control treatment. Salt treatments demonstrated a nonsignificant effect on leaf fresh and dry weight, root length and stomatal conductance. Similarly, drought stress significantly reduced the leaf fresh weight, leaf dry weight, plant height, stomatal conductance, and NPR with maximum reduction under severe drought condition (100 g L-1 PEG-6000), where the values were 31.01, 30.39, 35.09, 49.19 and 46.93% lower respectively than control plants. In this study, ABA application had not significantly influenced the morpho-physiological traits of S. canadensis. Reduced plant height, SDW and NPR under both stresses and reduced WUE and intracellular CO2 under salt stress suggest some degree of phenotypic plasticity under these stress conditions. [ABSTRACT FROM AUTHOR]

Sosnowsky's hogweed (Heracleum sosnowskyi Manden.) is an invasive species becoming an increased problem in the Europe including the Baltic region. It is an aggressive weed that poses a threat to human health. It is extremely difficult to control this plant, especially in the locations where chemical control is impossible. The purpose of the research was to evaluate the efficiency of non-chemical control methods of cutting and shading for 1st- and 2nd-year H. sosnowskyi plants as well as thermal control by heating with water steam at different growth stages. The study was carried out in Ukraine over the period of 2013-2020. To test the efficacy of cutting and shading aboveground parts of H. sosnowskyi, two field trials were conducted. Second-year plants were able to regenerate their aboveground part. Cutting of the 2nd-year shoots of H. sosnowskyi reduced the aboveground mass by 89.8-90.3%. An effective control of H. sosnowskyi was root removal in the 10 cm soil layer. Removal of the aboveground part of plant was less effective because of a high H. sosnowskyi regeneration, and the efficacy of control significantly decreased. The 1st-year plants of H. sosnowskyi at the 4-leaf stage were sensitive to covering by a plastic film. Shading for 30 days on juvenile plants ensured the sufficient efficacy of control. Thermal control (at a steam temperature of ≥95°C) was most efficient when H. sosnowskyi plants were at the cotyledon up to 4-leaf stage. Using of two non-chemical methods could have an effective control of 1st- and 2nd-year plants of H. sosnowskyi. [ABSTRACT FROM AUTHOR]

The invasive annual grasses barb goatgrass (Aegilops triuncialis L.) and medusahead (Elymus caput-medusae L.) are widespread in western states and present management challenges on grasslands. To develop an integrated management strategy for these species, we treated sites in five pastures in Mendocino County, comparing combinations of intensive sheep grazing, glyphosate herbicide (low and high), and application timings (tillering, boot and heading stage). We found that grazing alone reduced barb goatgrass spikelet densities by 68% and the number of seeds per spikelet by 35%. Both rates of glyphosate application without grazing had similar effects on seed production. High and low glyphosate application at tillering resulted in almost complete control of both target species. Boot- and heading-stage applications reduced barb goatgrass density by 39% and 32%, respectively. Application at the boot stage also resulted in an 82% reduction in number of seeds per barb goatgrass spikelet. Our results suggest that intensive grazing may be a useful management strategy to reduce barb goatgrass and medusahead spikelet densities and barb goatgrass seed numbers, especially when integrated with a boot- or heading-stage glyphosate application.

The work was carried out with the objective of determining the spatial and temporal distribution of Albizia procera (Roxb.) Benth species in sugarcane areas in Cuba. For this purpose, the information contained in the database generated by the weed identification surveys carried out in the period 2016-2020 by the Integral Weed Control Service (SERCIM) of the Instituto de Investigaciones de la Caña de Azúcar (INICA) was used. The surveys were conducted by the visual method, walking the field along its diagonals, with the use of manuals or catalogs in digital or printed format. The magnitude of the infestation was evaluated through the frequency and area infested. The results showed that in the period 2016-2020, the species presented frequency values in the Accidental category, with an increasing trend. The highest frequency was found in the western region and the largest plagued area in the central region. The surveys evidenced the presence of this species in all stages of the development and harvest cycles of sugarcane. It is recommended that a management strategy be developed to help reduce infested areas.

Mycoparasitic interactions are common in nature, form part of the microbiota of plants, and are considered significant contributors to fungus-fungus antagonism. Mycoparasites kill plant pathogens, protect the plant from abiotic and biotic stressors, and reduce disease incidence and severity at the plant population level. Their exploitation as biocontrol agents in agriculture is well documented. However, mycoparasites may potentially affect classical fungal biocontrol agents of invasive weed species. Classical biological control, or biocontrol, of invasive weeds involves the intentional introduction of exotic, usually co-evolved plant pathogens and insects, for permanent establishment and long-term control of the target plant. Agent establishment, effectiveness, and safety are the critical elements for a successful weed biocontrol programme. Establishment and effectiveness of agents on the invasive plant often vary throughout the invaded range with about two-thirds of weed biocontrol agents failing to suppress their target weed. There are many documented reasons why weed biocontrol agents do not establish or are ineffective when they do, and the presence and accumulation of natural enemies in the invaded range is one of them. Endophyte-enriched, invasive weeds and those forming mutualistic associations with indigenous, native endophytes could explain the lack of consistency of some classical biological control introductions. However, another variable could be factored into the mix: mycoparasitism, where one fungus parasitises another, the natural enemies of the plant’s natural enemies. In this review article, we introduce the concept of invasive weed biocontrol and the history of using plant pathogens as biocontrol agents. We discuss the success and failure of fungal agent programmes and delve into the patterns of success or failure, with a focus on the potential antagonistic role of endophytes and mycoparasites.

Weeds are considered the main reason for crop yield loss in the world. Weed control and management include various treatments such as cultural, physical, chemical, and biological methods. Chemical control of weeds is the most common method; however, the application of commercial synthetic herbicides caused several dangerous hazards in the environment including the appearance of resistant weed biotypes. Prosopis farcta (Banks & Sol.) J.F.Macbr. (Family: Fabaceae), is a common weed plant in the Middle East, where it is hard to eliminate due to its deep and overlapped roots. On the other side, it has many traditional uses around the world. Herein, the essential oil (EO) of P. farcta above-ground parts was extracted via hydrodistillation techniques and then analyzed using gas chromatography-mass spectroscopy (GC-MS). From the GC-MS analysis, 47 compounds were identified with a relative concentration of 98.02%, including terpenes as the main components (95.08%). From overall identified compounds, cubenol (19.07%), trans-chrysanthenyl acetate (17.69%), torreyol (8.28%), davana ether (3.50%), camphor (3.35%), and farnesyl acetone (3.13%) represented the abundant constituents. Furthermore, the phytotoxic activity of the P. farcta EO was assessed against the weed Dactyloctenium aegyptium (L.) Willd. The EO of P. farcta, at a concentration of 100 µL L−1, significantly inhibited the germination, seedling shoot growth, and seedling root growth by 64.1, 64.0, and 73.4%, respectively. The results exhibited that the seedling root growth is the most affected followed by the seed germination and seedling shoot growth with respective IC50 at 64.5, 80.5, and 92.9 µL L−1. It can be concluded that weeds are not absolutely harmful, but they may have beneficial uses, such as, for example as a source of phytochemicals with application in weed control practices (bioherbicides). It is advised to conduct additional research to characterize the allelopathic action of the major chemicals in their pure form, either alone or in combination, against a variety of weeds.

The threat posed by poisonous weeds to grassland ecosystems may be exacerbated by climate change mainly driven by carbon dioxide (CO2) emissions. Achnatherum inebrians is a common and poisonous grassland weed that is seriously endangering the sustainable development of prairie animal husbandry in Western China. Understanding the influence of future climate change under different CO2 emission scenarios on the potential distributions of A. inebrians is critical for planning agricultural strategies to manage the continued invasion. An ecological niche model (ENM) was developed using Maxent to predict the potential distribution of A. inebrians under three different CO2 emission scenarios. Occurrence records of A. inebrians were selected utilizing the nearest neighbor method. Six environmental variables, which were identified through principal component analysis, correlation analysis and their contribution rates, were used to perform the ENM. At the same time, considering the uncertainties of predicting future climates, four global circulation models were used for the Maxent projections with average results calculated. Our results demonstrate differential influences of various CO2 emission scenarios on the potential distributions of A. inebrians. Before 2050, high CO2 emission scenarios resulted in a wider potential distribution of A. inebrians, when compared to low CO2 emission scenarios. However, after 2050, the low CO2 emission scenarios were more conducive to an expanded potential distribution. In addition, after 2050, high CO2 emission scenarios maintain the geographical distribution centroids of A. inebrians in lower latitudes, while low CO2 emission scenarios result in distribution centroids rising to higher latitudes. Further, low CO2 emission scenarios resulted in the average potential distribution elevation dropping lower than in high CO2 emission scenarios. [ABSTRACT FROM AUTHOR]

The species Pleurotus ostreatus is an edible mushroom with a high commercial value, cultivated for its ease and adaptability in substrates based on agro-industrial waste. The plant species Solanum elaeagnifolium and Salsola kali are two invasive weeds that spread rapidly in crops, ruderal or urban areas, representing high-cost agricultural losses and environmental impact. The hypothesis of this research was that at least one of the weeds would increase the production and quality of P. ostreatus. The objective was to evaluate the biological efficiency and carpophore productivity of P. ostreatus with the use of substrates elaborated and combined from S. elaeagnifolim and S. kali. The fungal cultures were carried out with substrates generated from mixtures of weeds and using wheat straw as a control; from these combinations, seven treatments and four replicates were obtained in a completely randomized design. The carpophores obtained were measured for the width and length of the pileus and stipe, total production (g), biological efficiency (%), and proximate analysis of the harvested mushrooms was performed. Maximum production was 23.30 mushrooms, with minimum of 3.67 carpophores. The width and length of the pileus were 8.30-11.70 cm and 8.40-11.40 cm, respectively. The stipe length variable showed widths of 1.40- 2.30 cm and lengths of 2.80-6.20 cm. The weights obtained were up to 358.33 g, with a minimum of 95.10 g. Proximate analysis showed carpophores with the following composition: 82.25-91.37 % moisture; 1.71 to 13.66 % ash; 15.70 to 20.93 % protein; 0.40 to 1.55 % lipids and 8.60-17.7 % dry matter. The variables evaluated showed differences (p ≤ 0.05), being the substrates made with 100 % S. elaeagnifolium the ones with the highest biological efficiency, carpophore production, harvest weight and nutritional value. The species P. ostreatus proved to be efficient in providing substrate for two weeds, as well as producing carpophores with high protein content. [ABSTRACT FROM AUTHOR]

Ambrosia trifida L. belongs to the group of invasive weeds, which in colonized areas cause great damage to the biodiversity of autochthonous flora and vegetation as well as in plant production. It originates from North America wherefrom it has spread to many parts of Europe. In Serbia it is currently locally present in the area of Bačka (the northern region of the country). Early and rapid growth rate, vegetative and generative production, high degree of morphological and reproductive plasticity have given it a competitive advantage over many other weeds, hence in many countries it is considered one of the most problematic weeds in agricultural production. A. trifida could cause great damage in root crops, vegetable gardens and orchards and its harmfulness is measured by the negative impact on biodiversity by suppressing indigenous and other non-indigenous species. With its allergens, A. trifida negatively affects human health. Observing its vegetative and generative potential and climate change on the other hand, recent research indicates the potential for the spread of A. trifida in our country and in Europe, which could be a serious risk for agrophytocenoses and the ecosystem as a whole. In 2019, it was added to the EPPO A2 List of quarantine pests recommended. It can be controlled with the use of mechanical, biological and chemical measures.

Natural herbicides based on essential oils (EOs) extracted from aromatic plants are gaining relevance in contemporary agriculture. Due to their allelopathic properties, they have an inhibitory effect on the germination and growth of different species, having, in general, the advantage of high specificity. For this reason, the analysis of the effects of these natural compounds on noxious weeds is continuously increasing. In the present study, three commercial EOs extracted from Mentha piperita L., Thymbra capitata (L.) Cav. and Santolina chamaecyparissus L. were tested on two invasive weeds with an increasing presence in southern Europe, Erigeron bonariensis L. and Araujia sericifera Brot. Five concentrations (0.125, 0.25, 0.50, 1 and 2 µL mL–1) were tested in a randomized manner for each essential oil and five replicates with 20 seeds each for E. bonariensis and 10 replicates with 10 seeds each for A. sericifera. Two higher concentrations of 4 and 8 μL mL–1 of the three EOs were applied with irrigation on the plants of the two species at the vegetative growth stage. The number of replicas for each treatment and species was 7. The results obtained confirmed the significant inhibitory effects on seed germination and early seedling development, especially in E. bonariensis; of the three EOs, peppermint had the strongest effect, completely preventing germination in both species. Multivariate analysis, performed on several morphological traits scored after one month of treatment in young plants, showed a different pattern: the highest inhibition was recorded in A. sericifera and the greatest reduction in growth in the treatment with the highest dose of Santolina EO. The results obtained revealed the efficacy of these natural compounds and the specificity of their toxicity according to the species and stage of development. [ABSTRACT FROM AUTHOR]

Solanum elaeagnifolium Cav. is known to be one of the most invasive species worldwide. In this study, laboratory and greenhouse experiments were carried out to investigate the allelopathic properties of S. elaeagnifolium vegetative parts, root parts, fruit mucilage, and exudate extracts on plant communities and soil properties. In addition, the extract profiles of allelochemicals were quantified and their influence on soil properties and microorganisms was determined. Overall, the allelopathic performance of S. elaeagnifolium was established depending on the extract types, used concentrations, and target species. The doseresponse activity indicated that vegetative parts extract showed the greatest allelopathic potential followed by root parts extract. Subsequently, mucilage extract had a moderate inhibitory potential, while root exudates showed the least activity. The same trend with slight response was detected in soil properties of pH and EC properties. Polyphenols, in the range of 5.70–0.211 mg · g–1 and flavonols, in the range of 2.392–0.00 mg · g–1, were found in the analyzed samples extracted by ethyl acetate using LC-DAD-MS. The total phenol amount was 1.67 to 1.89 in the rhizosphere and 0.53 to 087 mg · g–1 in non-rhizosphere soils. Solanum elaeagnifolium exhibited a greater significant suppression of fungi count in both high and low-density areas than in rhizosphere bacteria. In conclusion, the strong and broad spectrum allelopathic potentials may enhance the ability of S. elaeagnifolium to impact seed germination and seedling growth of neighboring species. These biochemical weapons may play a critical role to facilitate their invasion and establishment in new agroecosystems. [ABSTRACT FROM AUTHOR]