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Body size is a trait that can affect plant–pollinator interaction efficiency and plant reproductive success. We explored the impact of intraspecific size shifts on the interactions between pollinators and flowering plants under controlled conditions. We considered two development conditions leading to the production of large and small individual flowers of Borago officinalis and Echium plantagineum. We also used the natural variability of worker size within bumblebee colonies to isolate small and large workers. We performed a fully crossed experiment with the two flower sizes of each plant species and the two sizes of bumblebee workers. Our results show that the size of both partners did not affect bee foraging behavior in most of the evaluated parameters and both bee sizes were equally efficient in depositing pollen. Significant differences were found only in pollen deposition across the life of a flower in small flowers of B. officinalis, with the greatest quantity of pollen deposited by small bees. We did not find a relationship between pollinator size and plant fitness. Our results suggest that generalist plant–pollinator interactions may be resilient to future potential mismatches in the size of the partners but remain to be tested if they are still resilient under the new environmental conditions resulting from global changes. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) pose a serious threat to biodiversity, agriculture, health, and economies globally. Accurate mapping of IAPs is crucial for their management, to mitigate their impacts and prevent further spread where possible. Remote sensing has become a valuable tool in detecting IAPs, especially with freely available data such as Sentinel-2 satellite imagery. Yet, remote sensing methods to map herbaceous IAPs, which tend to be more difficult to detect, particularly in shrubland Mediterranean-type ecosystems, are still limited. There is a growing need to detect herbaceous IAPs at a large scale for monitoring and management; however, for countries or organizations with limited budgets, this is often not feasible. To address this, we aimed to develop a classification methodology based on optical satellite data to map herbaceous IAP's using Echium plantagineum as a case study in the Fynbos Biome of South Africa. We investigate the use of freely available Sentinel-2 data, use the robust non-parametric classifier Random Forest, and identify the most important variables in the classification, all within the cloud-based platform, Google Earth Engine. Findings reveal the importance of the shortwave infrared and red-edge parts of the spectrum and the importance of including vegetation indices in the classification for discriminating E. plantagineum. Here, we demonstrate the potential of Sentinel-2 data, the Random Forest classifier, and Google Earth Engine for mapping herbaceous IAPs in Mediterranean ecosystems. [ABSTRACT FROM AUTHOR]

Green roofs (GRs) are proposed to offset against numerous environmental and socio-economic concerns associated with climate change and urban sprawl. In Mediterranean urban areas, to protect and conserve biodiversity through GRs, the use of native plant species from arid environments and with shallow roots is generally recommended. In north Europe, Echium vulgare L. is widely used on GRs for its tolerance to abiotic stresses and its attractiveness for bees; unfortunately, since this species requires cold winters to induce flowering and warm wet summers for vegetative growths, its adaptability to Mediterranean GRs has been questioned. The current study is based on the hypothesis that Echium plantagineum L. can adapt better to the Mediterranean environment than E. vulgare and offer blooms to pollinators, thus providing the important urban ecosystem service (UES) of protecting entomofauna biodiversity. To compare the adaptability of E. plantagineum vs. E. vulgare, both Echium species were grown and studied on the extensive GR installed at ENEA Casaccia Research Center, in the north of Rome, Lazio, Italy. The comparative analysis of the GR performance of the two species was based on several plant-related traits, including seed morphology, rosette stage, inflorescence, flower and root-related traits, and their biological life cycle, most of them showing significant differences (for example, rosette area was 1.42-fold major in E. plantagineum than in E. vulgare). The information provided in this manuscript will be useful to update the herbarium records for conservation biology. A dramatic water stress was purposely applied in the GR before the end of the hot summer season, and while E. plantagineum faced with success the imposed dehydration (88.4% vegetation cover), E. vulgare did not (7.5% vegetation cover), presumably because of its biennial life cycle which did not allow it to complete seed maturation (only 46.9% percentage mature seeds in E. vulgare respect to 89.5% in E. plantagineum). In summary, as the main result, this work shows that in Mediterranean areas, the inclusion of E. plantagineum in seed mixes for flower meadow GRs could represent a valuable alternative to E. vulgare in temperate areas, providing a safeguard for pollinators and allowing water and energy saving. [ABSTRACT FROM AUTHOR]

12-Oxophytodienoate reductase (OPR) enzymes in dicots are categorized as flavin mononucleotide (FMN)–dependent oxidoreductases and are divided into two subgroups. Although subgroup II OPRs have been identified as being involved in a critical step in the production of jasmonic acid (JA), the functions of subgroup I OPRs are uncertain. In this study, we cloned a potential subgroup I OPR gene, EpOPR1, from Echium plantagineum using comparative transcriptome analysis. EpOPR1 expression was found to be significantly increased in root samples containing secondary metabolites such as shikonin and its derivatives. Using a transgenic hairy root system, we further explored the role of EpOPR1 in the production of these secondary metabolites. The results indicated that although the chemical profile of EpOPR1 overexpressing hairy roots (OPRO) is similar to that of the empty vector hairy roots (EV), the EpOPR1 overexpressing line considerably increased the yield of acetylshikonin by around two-fold. Our findings shed light on the potential role of subgroup I OPRs in E. plantagineum secondary metabolism regulation. [ABSTRACT FROM AUTHOR]

Echium seed oil has been considered an important alternative source of omega 3 fatty acids (n‐3 FA) for human consumption. Considering the oxidative instability of n‐3 FA richer oils, the objective of this study was to determine the chemical and sensory parameters of the oil obtained from Echium plantagineum seeds obtained by three extraction methods (hydraulic press: HYD; continuous screw press: PRESS; and solvent technique: SOLV). Stearidonic acid (C18:4, n3), the most important n‐3 FA present in the oil, changed from 12.5% to 12.7%. Regarding the minor compounds, PRESS sample showed the highest concentration of gamma‐tocopherol (782.24 mg/kg oil), while SOLV samples presented the highest amount of β‐sitosterol (73.46 mg/100 g) with no difference of campesterol concentration (159.56 mg/100 g) among the samples. Higher values of total phenolics (19.65 mg GAE/kg oil) and β‐carotene (34.83 mg/kg oil) were also found in the SOLV samples, suggesting the influence of hexane in the extraction of these bioactive compounds. High resolution mass spectrometry identified caffeic acid and its derivatives as the main phenolic compounds present in the echium oil. PRESS sample showed the best oxidative stability as measured by PV (0.61 mmol/kg oil) and malondialdehyde (173.13 µmol), probably due to faster time of processing compared to HYD and SOLV samples. Our data showed that the extraction method changed the chemical composition of the minor compounds in the echium oil, but these alterations did not reduce its nutritional quality or sensory acceptability. Practical Application: Echium oil represents a great potential source of omega 3 fatty acids, but there is not enough information about its oxidative stability and chemical composition, especially toward minor compounds. Our study characterizes echium oil composition obtained from three extraction methods, contributing to amplify the technical information about this important alternative oil for human consumption. [ABSTRACT FROM AUTHOR]

Besides being a common weed, the presence of Echium plantagineum L. in food and feed commodities can represent a safety hazard due to their content in pyrrolizidine alkaloids. In this study, the complete chloroplast of E. plantagineum isolate BPTPS251 is described, being the first available plastome from an isolate belonging to the Echium genus. The chloroplast genome is 149,776 bp in length with 37.5% GC content, displaying a quadripartite structure that contains a pair of inverted repeats regions (25,754 bp each), separated by a large single-copy (80,978 bp) and a small single-copy (17,290 bp) regions. A total of 131 genes were predicted, including 37 tRNA genes, 8 rRNA genes, and 86 protein-coding genes. The phylogenetic analysis confirmed the placement of E. plantagineum under the Boraginaceae family, belonging to the Boraginales order. This study will contribute to conservation, phylogenetic, and evolutionary studies, as well as DNA barcoding applications for food and feed safety purposes. [ABSTRACT FROM AUTHOR]

Shikonins are the main naphthoquinones in the root periderm of Echium plantagineum, as well as the hypocotyl and root hairs of young seedlings. These red pigments can be used as dyes or for medicinal uses since ancient times. Geranylhydroquinone 3″-hydroxylase (GHQH) has recently been identified to catalyze the C-3″ site of geranylhydroquinone to form 3″-hydroxy-geranyl-hydroquinone in shikonin biosynthetic pathway. In this study, we cloned a geranylhydroquinone 3″-hydroxylase candidate gene (EpGHQH1) from E. plantagineum, and further characterized its function in shikonin biosynthesis using the hairy root system by overexpression and RNA interference strategies. The obtained results showed that overexpression of EpGHQH1 increased the accumulation of shikonins, showing 2.1-fold higher in acetylshikonin yield than that of control lines. On the contrary, down-regulation of EpGHQH1 resulted in a decline in shikonin production. Furthermore, the EpGHQH1 expression levels in germinated seedlings showed a high positive relation with shikonin accumulation. These findings demonstrated the function of EpGHQH1 in enhancing shikonin biosynthesis of E. plantagineum, and provided the first example of transgenic hairy root system from E. plantagineum for functional analysis of genes in metabolite biosynthesis. Key message: We reported a possible GHQH gene (EpGHQH1), and demonstrated its positive role in shikonin biosynthesis of E. plantagineum with the transgenic hairy root system by overexpression and RNAi strategies. [ABSTRACT FROM AUTHOR]

Echium seed oil is an alternative source of omega 3 fatty acids but it is highly susceptible to oxidation. A combination of three natural strategies was proposed in this study aiming to improve the oxidative stability of echium oil obtained by pressing (PO) or solvent extraction (PSO), kept in the storage condition for 180 days or during the consumption for 30 days. Our results showed that the reduction of temperature was sufficient to keep the oil stable during storage for both samples. During the consumption time, the best stability was achieved by adding a mixture of antioxidants, composed of sinapic (500 ppm), ascorbic (250 ppm), and citric (150 ppm) acids, and/or 20% of high oleic sunflower oil. The combined strategies promoted a 34 to 80% reduction of peroxide value and 0 to 85% reduction of malondialdehyde concentrations in the samples, showing to be a feasible and natural alternative to improve the oxidative stability of echium oil. Practical Application: Our study successfully applied an optimized combination of simple and low‐cost strategies to enhance the chemical stability of echium seed oil. As the use of echium oil expands around the world, the oil industry and final consumers may benefit from our results to increase the oil shelf‐life. [ABSTRACT FROM AUTHOR]

Oil extraction from seeds of purple viper's bugloss (Echium plantagineum) was carried out using different solvents (chloroform:methanol, n‐hexane, ethanol, 2‐propanol and ethyl acetate) at room temperature and also using Randall extraction. Extraction yields were calculated and oils were analyzed in terms of fatty acid profiles and distribution among lipid classes, total polyphenol content, oxygen radical absorbance capacity (ORAC) and phytosterol content. No considerable differences were found on fatty acid profiles and distribution in oils regardless of the solvent and temperature used for the extraction. However, ethanol combined with Randall extraction (85 °C for 1 hour) offered the best results in terms of total polyphenol content (20.9 mg GAE/100 g oil), ORAC (468.0 μmol TE/100 g oil), and phytosterol amount (437.2 mg identified phytosterols/100 g oil) among all assayed extraction methods. A higher extraction temperature led to significantly higher concentrations of bioactive compounds and ORAC values in the oil when ethanol or 2‐propanol were used as extracting solvent, but that was not the case using n‐hexane except for the concentrations of β‐sitosterol and stigmasterol, which were significantly higher using Randall extraction than room temperature extraction with n‐hexane. Ethanol is classified as a "green solvent," and it could be considered a suitable option to produce oil from E. plantagineum seeds with a higher antioxidant capacity and bioactive compound concentration than the current commercial oil, which is usually extracted with n‐hexane. [ABSTRACT FROM AUTHOR]

In this work, gamma‐linolenic acid (GLA) and stearidonic acid (SDA) are successfully concentrated as free fatty acids (FFA) and ethyl esters (EE) using the urea complexation method at room temperature and two sources of these fatty acids: commercial Echium plantagineum seed oil as well as extracted oil from this species which is grown in Chile. Concentration factors (% fatty acid in the concentrate/% fatty acid in the original oil) for both fatty acids are found to be between 2.35 and 2.65, although they are more efficiently concentrated as FFA than as EE using both commercial and extracted oils. This is the first work which reports the use of Echium plantagineum seed oil from Chilean origin to produce GLA and SDA concentrates as FFA and EE, with similar results that those obtained with commercial Echium oil. Practical Applications: The interest for GLA and SDA as functional ingredients is increasing in the last few years because of their beneficial effects for human health and their plant origin, as they are mainly provided by seed oils from some Boraginaceae species. In this work, GLA and SDA are selectively concentrated from the rest of fatty acids contained in Echium seed oil by the urea method at room temperature, which is a cheap, safe, and easily scalable process. These concentrates, especially as FFA because of their nutritional characteristics versus EE, may become high added‐value ingredients to be incorporated to functional oils or even substrates for the enzymatic synthesis of structured lipids providing GLA and SDA with a higher bioefficiency than currently available oils. Operational scheme developed in this work which consists of: 1) derivatization of Echium plantagineum oil from two origins (extracted from Chilean seeds and commercial oil) to free fatty acids (FFA) and ethyl esters (EE) and 2) processing of FFA and EE by urea at room temperature to concentrate GLA and SDA. [ABSTRACT FROM AUTHOR]

Echium plantagineum is a significant pasture weed in the Mediterranean climatic zone of several countries, including Australia. This invasive weed, introduced as an ornamental into Australia (where it is known as Paterson's curse), quickly became established and is now a significant weed of agriculture. Although E. plantagineum is a well-established, highly competitive weed that thrives under disturbance and is tolerant of a wide variety of conditions, including varying soil moisture and drought, and some aspects of its ecology remain unknown. This study investigated germination response to temperature and light, pH, soil moisture, salinity, and pre-germination exposure of seed to heat and smoke. Temperature was found to be more influential on germination than light and the species is tolerant to a wide range of pH. However, available moisture may limit germination, as may elevated salinity. Management of this weed requires approaches that minimise soil seedbank input or prevent germination of soil seedbanks. [ABSTRACT FROM AUTHOR]

1. In insect-pollinated plants, pollinator attraction is influenced by flowers (e.g. number, size) and their associated rewards (e.g. pollen, nectar). These traits can depend on plant interactions. Indeed, below-ground competition between plants can lead to a decrease in flower or reward production in insect-pollinated species. 2. Wind-pollinated plants, in particular, which are almost never studied in plant-pollinator networks, can alter insect-pollinated plants' attractiveness through competition for nutrients. The response of pollinators to such changes has never been investigated. 3. A pot experiment was carried out in which an insect-pollinated species, Echium plantagineum, was grown in binary mixture with three wind-pollinated species selected to exert a panel of competitive interactions. Below-ground competition was controlled using dividers limiting interspecific root competition. Floral traits of E. plantagineum ( i.e. flower production, floral display size, flower size and nectar production) were measured. For each species mixture, the visits ( i.e. first visit, number of visits, 10-min sequences) of Bombus terrestris individuals released in a flight cage containing two pots were followed, one with and one without below-ground competition. 4. Below-ground competition significantly affected nectar's sucrose concentration but did not influence flower and nectar production. Likewise, pollinator visits were not influenced by below-ground competition. Competitor identity significantly influenced flower and reward production of E. plantagineum, with a decrease in the presence of the most competitive wind-pollinated species. A tendency for faster flower visitation events was also detected in the presence of the least competitive competitor. This study raises new questions regarding the influence of wind-pollinated plants on plant-pollinator interactions. [ABSTRACT FROM AUTHOR]

In this study, the conservation status was estimated for six important rare and endemic plant taxa from the watershed of the middle section of river Devoll. It was assessed by the Geospatial Conservation Assessment Tool (GeoCAT). The GeoCAT method is a standardized method for determination of the conservation status of the Red List species. As a result, Bubon albanicum and Echium maculatum were estimated for the first time as Endangered, while Bornmuellera baldaccii subsp. baldacii and subsp. rechingeri, respectively, were estimated as Endangered and Critically Endangered. The conservation status of Endangered was confirmed for Campanula hawkinsiana, while Festucopsis serpentini and Cistus sintenisii were proposed to be included in the IUCN Red List of species as Vulnerable and Endangered, respectively. Comments on the species distribution were also included. [ABSTRACT FROM AUTHOR]

Bioactive plant secondary products are frequently the drivers of complex rhizosphere interactions, including those with other plants, herbivores and microbiota. These chemically diverse molecules typically accumulate in a highly regulated manner in specialized plant tissues and organelles. We studied the production and localization of bioactive naphthoquinones (NQs) in the roots of Echium plantagineum, an invasive endemic weed in Australia. Roots of E. plantagineum produced red-coloured NQs in the periderm of primary and secondary roots, while seedling root hairs exuded NQs in copious quantities. Confocal imaging and microspectrofluorimetry confirmed that bioactive NQs were deposited in the outer layer of periderm cells in mature roots, resulting in red colouration. Intracellular examination revealed that periderm cells contained numerous small red vesicles for storage and intracellular transport of shikonins, followed by subsequent extracellular deposition. Periderm and root hair extracts of field- and phytotron-grown plants were analysed by UHPLC/Q-ToF MS (ultra high pressure liquid chromatography coupled to quadrupole time of flight mass spectrometry) and contained more than nine individual NQs, with dimethylacrylshikonin, and phytotoxic shikonin, deoxyshikonin and acetylshikonin predominating. In seedlings, shikonins were first found 48 h following germination in the root-hypocotyl junction, as well as in root hair exudates. In contrast, the root cortices of both seedling and mature root tissues were devoid of NQs. SPRE (solid phase root zone extraction) microprobes strategically placed in soil surrounding living E. plantagineum plants successfully extracted significant levels of bioactive shikonins from living roots, rhizosphere and bulk soil surrounding roots. These findings suggest important roles for accumulation of shikonins in the root periderm and subsequent rhizodeposition in plant defence, interference, and invasion success. [ABSTRACT FROM AUTHOR]

Metabolic profiling allows for simultaneous and rapid annotation of biochemically similar organismal metabolites. An effective platform for profiling of toxic pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) was developed using ultra high pressure liquid chromatography quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry. Field-collected populations of invasive Australian weeds, Echium plantagineum and E. vulgare were raised under controlled glasshouse conditions and surveyed for the presence of related PAs and PANOs in leaf tissues at various growth stages. Echium plantagineum possessed numerous related and abundant PANOs (>17) by seven days following seed germination, and these were also observed in rosette and flowering growth stages. In contrast, the less invasive E. vulgare accumulated significantly lower levels of most PANOs under identical glasshouse conditions. Several previously unreported PAs were also found at trace levels. Field-grown populations of both species were also evaluated for PA production and highly toxic echimidine N-oxide was amongst the most abundant PANOs in foliage of both species. PAs in field and glasshouse plants were more abundant in the more widely invasive species, E. plantagineum, and may provide competitive advantage by increasing the plant's capacity to deter natural enemies in its invaded range through production of novel weapons. [ABSTRACT FROM AUTHOR]

UV-B radiation represents a potentially selective, yet little studied environmental factor for plant invasions, especially with respect to germination characteristics and seedling establishment in areas of high UV-B exposure such as New Zealand. To explain invasive potential of plant species pre-adaptation and local adaptation to selection factors in the invaded range are two frequently consulted concepts. To test for the relevance of these mechanisms, it is necessary to compare both invasive and non-invasive species, as well as native and exotic origins of invasive species. In the present study, germination success of two congeneric species pairs of the genera Verbascum (Scrophulariaceae) and Echium (Boraginaceae) were investigated under high UV-B intensities. Each genus comprised one species that has successfully invaded New Zealand grasslands and one species that was introduced but has not been invasive in New Zealand. In an among-species approach, pre-adaptation was tested by comparing germination success of native (European) origins of all four species in relation to their different invasive success in New Zealand. In a within-species comparison, native (European) and exotic (New Zealand) origins of the two invasive species were compared to test for local adaptation to UV-B in the invaded range. In both approaches, UV-B radiation inhibited the germination success of all study species. However, the comparison of invasive and non-invasive species of the two genera showed no UV-B-specific pre-adaptation of invasive species to high UV-B intensities. Higher germination success of invasive species probably led to an establishment advantage during colonization of the invaded range. Although local adaptation of exotic populations to UV-B could not be demonstrated in the within-species approach, a genetic shift in germination velocity between native and exotic origins was found. These differences may be ascribed to other relevant environmental factors, e.g. overall irradiation and drought, inducing similar plant responses as under UV-B radiation. [ABSTRACT FROM AUTHOR]

Echium (Echium plantagineum L.) is an alternative oilseed crop in summer-wet temperate regions that provides floral resources to pollinators. Its seed oil is rich in omega-3 fatty acids, such as stearidonic acid, which is desired highly by the cosmetic industry. Seeds were sown in field plots over three years in western Minnesota in spring (early-sown) or early summer (late-sown), and flower abundance, pollinator visitation, and seed yields were studied. Initial flowering commenced 41 to 55 d after sowing, and anthesis duration (first flowering to harvest) was 34 to 70 d. Late sowing dates delayed anthesis, but increased the intensity of visitation by pollinators. Cumulative flower densities ranged from 1 to 4.5 billion ha−1. Flowers attracted numerous honey bees (Apis mellifera L.), as many as 35 per minute of observation, which represented about 50% of all insect visitors. Early-sown echium produced seed yields up to 750 kg ha−1, which were 2–29 times higher than those of late-sown echium. Early sowing of echium in Minnesota provides abundant floral resources for pollinators for up to two months and simultaneously produces seed yields whose profits rival those of corn (Zea mays L.). [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the anti-allergic potential of Echium plantagineum L. bee pollen and to characterize its primary metabolites. The activity of E. plantagineum hydromethanolic extract, devoid of alkaloids, was tested against β-hexosaminidase release in rat basophilic leukemic cells (RBL-2H3). Two different stimuli were used: calcium ionophore A23187 and IgE/antigen. Lipoxygenase inhibitory activity was evaluated in a cell-free system using soybean lipoxygenase. Additionally, the extract was analysed by HPLC-UV for organic acids and by GC-IT/MS for fatty acids. In RBL-2H3 cells stimulated either with calcium ionophore or IgE/antigen, the hydromethanolic extract significantly decreased β-hexosaminidase release until the concentration of 2.08 mg/mL, without compromising cellular viability. No effect was found on lipoxygenase. Concerning extract composition, eight organic acids and five fatty acids were determined for the first time. Malonic acid (80%) and a-linolenic acid (27%) were the main compounds in each class. Overall, this study shows promising results, substantiating for the first time the utility of intake of E. plantagineum bee pollen to prevent allergy and ameliorate allergy symptoms, although a potentiation of an allergic response can occur, depending on the dose used. [ABSTRACT FROM AUTHOR]

Questions Which are the most effective plant communities for honeybee foraging and honey production in Mediterranean sylvo-pastoral systems? What is the relationship between flowering phenology and pollen occurring in honey sediments? Location Mediterranean sylvo-pastoral system in Gallura, Sardinia, Italy. Methods Phytosociological and phenological surveys were performed in a circular area of 1.5 km radius with a small apiary placed in the centre. Polleniferous and nectariferous values of plant communities were assessed based on the cover and the polleniferous and nectariferous value of each constituting species. Honey production was quantified during the main flow ( March- June) and subjected to melissopalynological analysis. Data were evaluated by ordination through principal components analysis and principal coordinates analysis. The latter utilized a new index, developed for calculating the phenological distances based on the individual distributions of flowering frequencies. Results Plant communities richest in species providing pollen and nectar were Rhamnus hedges. There was a close correlation between polleniferous and nectariferous values, suggesting that plant communities are important for honeybee foraging of both resources. The temporal flowering sequence ensured the supply of nectar and pollen throughout the spring season. Pollen foraged from 12 Trifolium species with different flowering phenology was the most abundant. Salix purpurea and Rhamnus alaternus were productive at the beginning of the season, followed by Lavandula stoechas, Echium plantagineum and E. italicum. Conclusions Plant communities vary in importance for honeybee foraging mainly due to differences in floristic composition and flowering phenology. Communities characterized by human presence (e.g. semi-natural grasslands and hedges) are the most relevant. Some target species (e.g. Trifolium spp.) favoured by grazing livestock ensure foraging for honeybees throughout the season. Plant communities of wild areas, such as the garrigue vegetation, provide foraging for unifloral valuable honey (i.e. ' Lavandula' honey). [ABSTRACT FROM AUTHOR]

The incidence and concentration of pyrrolizidine alkaloids (PAs) fromEchiumspp. plant have been defined in 103 Spanish honey samples. Each sample was examined to determine total pollen content, the percentage ofEchiumspp. pollen, and simultaneous measurements of PAs and theirN-oxides concentrations by the HPLC-ESI/MS method to identify the potential origin of PAs in honey. PAs were found in 94.2% of the raw honey samples analysed, in the range of 1–237 µg kg−1(average concentration = 48 µg kg−1). The PA pattern was clearly dominated by echimidine, lycopsamine and theirN-oxides, representing the 97.8% of total ∑PAs, and only echimidine and echimidine-N-oxide surpassed the 87% of total ∑PA content. Others PAs, seneciphylline and heliotrine-N-oxide, appear to be reported in a lower incidence and concentration (average of 3 and 1 µg kg−1, respectively). The Pearson Chi-squared test (p ≤ 0.01) confirms the non-correspondence between pollen plants and PA content. This study was also realised to generate a dataset in order to evaluate the potential risk of Spanish honeys containing PA plants belonging to the generaEchium. [ABSTRACT FROM AUTHOR]

Oxidative stress and inflammation play important roles in disease development. This study intended to evaluate the anti-inflammatory and antioxidant potential of Echium plantagineum L. bee pollen to support its claimed health beneficial effects. The hydromethanol extract efficiently scavenged nitric oxide (•NO) although against superoxide (O2•−) it behaved as antioxidant at lower concentrations and as pro-oxidant at higher concentrations. The anti-inflammatory potential was evaluated in LPS-stimulated macrophages. The levels of •NO and L-citrulline decreased for all extract concentrations tested, while the levels of prostaglandins, their metabolites and isoprostanes, evaluated by UPLC-MS, decreased with low extract concentrations. So, E. plantagineum bee pollen extract can exert anti-inflammatory activity by reducing •NO and prostaglandins. The extract is able to scavenge the reactive species •NO and O2•− and reduce markers of oxidative stress in cells at low concentrations. [ABSTRACT FROM AUTHOR]

We examined adaptive clinal variation in seed mass among populations of an invasive annual species, Echium plantagineum, in response to climatic selection. We collected seeds from 34 field populations from a 1,000 km long temperature and rainfall gradient across the species' introduced range in south-eastern Australia. Seeds were germinated, grown to reproductive age under common glasshouse conditions, and progeny seeds were harvested and weighed. Analyses showed that seed mass was significantly related to climatic factors, with populations sourced from hotter, more arid sites producing heavier seeds than populations from cooler and wetter sites. Seed mass was not related to edaphic factors. We also found that seed mass was significantly related to both longitude and latitude with each degree of longitude west and latitude north increasing seed mass by around 2.5% and 4% on average. There was little evidence that within-population or between-population variation in seed mass varied in a systematic manner across the study region. Our findings provide compelling evidence for development of a strong cline in seed mass across the geographic range of a widespread and highly successful invasive annual forb. Since large seed mass is known to provide reproductive assurance for plants in arid environments, our results support the hypothesis that the fitness and range potential of invasive species can increase as a result of genetic divergence of populations along broad climatic gradients. In E. plantagineum population-level differentiation has occurred in 150 years or less, indicating that the adaptation process can be rapid. [ABSTRACT FROM AUTHOR]

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Here we report that a synthesised form of a naturally occurring chemical (a butenolide, 3-methyl-2 H-furo[2,3- c]pyran-2-one) found in smoke can stimulate seedling emergence of the economically important weed species Avena fatua L. (Poaceae), Arctotheca calendula (L.) Levyns (Asteraceae), Brassica tournefortii Gouan (Brassicaceae), and Raphanus raphanistrum L. (Brassicaceae) under field conditions at rates equivalent to 2–20 g/ha a.i. The butenolide also stimulates germination of freshly collected seeds from wild populations of these species, as well as those of Sisymbrium orientale L. (Brassicaceae), Hordeum leporinum Link (Poaceae) and Echium plantagineum L. (Boraginaceae) under laboratory conditions, consistently greater than that of smoke water. Experiments using B. tournefortii seeds collected from several locations across Western Australia and in different growing seasons found that these factors significantly influence the butenolide response, implying a role of the maternal environment in seed germination/dormancy characteristics. This research highlights the potential of butenolide as an agent for broad acre weed control and land restoration. [ABSTRACT FROM AUTHOR]

1. Coupled plant–herbivore models, allowing feedback from plant to herbivore populations and vice versa, enable us to predict the impact of biocontrol agents on their target weed populations; however, they are rarely used in biocontrol studies. We describe the population biology of the invasive plantEchium plantagineumand the weevilMogulones larvatus, a biocontrol agent, in Australia. In order to understand the dynamics of this plant–herbivore system, a series of coupled models of increasing complexity was developed.2. A simple model was extended to include a seed bank, density-dependent plant fecundity, competition between weevil larvae and plant tolerance of herbivory, where below a threshold plants could compensate for larval feeding. Parameters and functional forms were estimated from experimental and field data.3. The plant model, in the absence of the weevil, exhibited stable dynamics and provided a good quantitative description of field densities before the weevil was introduced.4. In the coupled plant–herbivore model, density dependence in both plant fecundity and weevil larval competition stabilized the dynamics. Without larval competition the model was unstable, and plant tolerance of herbivory exacerbated this instability. This was a result of a time delay in plant response to herbivore densities.5. Synthesis and applications.The coupled plant–herbivore model allowed us to predict whether stable coexistence of target plant and biocontrol agents was achievable at an acceptable level. We found this to be the case for theEchium– Mogulonessystem and believe that similar models would be of use when assessing new agents in this and other invasive plant biocontrol systems. Density dependence in new biocontrol agents should be assessed in order to determine whether it is likely to result in the aims of classical biocontrol: low, stable and sustainable populations of plant and herbivore. Further work should be done to characterize the strength of density dependence according to the niche occupied by the biocontrol agent, for example the strength and functional form of density dependence in stem borers may be quite different to that of defoliators.Journal of Applied Ecology(2005)42, 70 –79doi: 10.1111/j.1365-2664.2005.00991.x [ABSTRACT FROM AUTHOR]

1. Echium plantagineum is native to the western Mediterranean Basin, where it is a common, but not dominant, component of species-rich annual grasslands. Since its introduction into Australia, E. plantagineum has spread to infest vast areas of predominantly agricultural land in south-east and south-west Australia, where it can be the dominant pasture species. 2. To unravel the ecological factors responsible for the high population abundance of E. plantagineum in Australia, its demography was compared between sites in the invaded and native ranges. Demographic parameters of E. plantagineum populations were estimated at a site near Canberra in south-eastern Australia, and at a site near Evora in southern Portugal. Identical factorial experiments were set up at each site with treatment combinations of the presence or absence of grazing and pasture competition. 3. The recruitment, survival, fecundity and seed bank dynamics of E. plantagineum populations were measured for each of the treatment combinations over 2 years at each site. These data allowed the estimation of demographic parameters describing the proportion of E. plantagineum individuals moving from one life-cycle stage to the next. 4. Seedling establishment fractions were two to five times greater at Canberra than at Evora, and seed bank incorporation rates were three times greater at Canberra than Evora. These demographic differences were those most likely to play an important role in the greater abundance of E. plantagineum in Australia compared with Mediterranean Europe. Neither seed bank survival rates nor seed production differed between populations at Canberra and Evora, while seedling survival rates were always lower at Canberra than at Evora. 5. Neither grazing nor pasture competition limited the seed production or seedling survival of E. plantagineum populations at Evora more than at Canberra. 6. An effective approach for the control of E. plantagineum in Australia may thus be through the... [ABSTRACT FROM AUTHOR]

Summary1. Root-feeding insect herbivores may suppress their host populations by altering the competitive balances within the plant community of the host-plant. In this study, repeated field experiments using caged and natural populations of a root-crown weevil, Mogulones larvatus, on the annual weed Echium plantagineum (Boraginaceae) were conducted with and without pasture competition in its exotic range. 2. The experiment used a split-plot design, excluding weevils with insecticide and plant competition through weeding. 3. The greatest effect of the weevils was observed when natural densities of weevils occurred on naturally growing E. plantagineum rosettes in the field. Weevils reduced plant survival by 43%, and the size and seed weight of survivors by 58% and 74%, respectively. 4. Pasture competition had a similar impact on E. plantagineum as the weevils for plant size and seed weight, except that there was no impact on rosette survival. There were also no significant interactions between the effects of weevils and competition. Most impact occurred in the second half of the growing season. 5. The number of weevil eggs and larvae and all plant reproductive parameters measured per unit biomass were independent of plant size. 6. Such impact experiments help develop simplified impact assessment methodologies for assessing the success of biological control projects in the field. [ABSTRACT FROM AUTHOR]

This study examines the oviposition response of a specialist weevil (Mogulones larvatus) to patches of its host, the noxious weed Paterson"s curse/salvation Jane (Echium plantagineum). We simultaneously examined the effect of patch size and plant density (and their interaction), on the recorded oviposition patterns. Our results show that oviposition first occurred on the largest patches with the highest number of plants. However, there was no significant effect of patch size or number of plants per patch at the end of the experiment. At this time the level of attack per plant was negatively correlated with plant density. This negative effect of density on the level of oviposition was not mediated by a reduction in plant size at higher densities. The pattern observed may indicate a risk-spreading strategy by females. [ABSTRACT FROM AUTHOR]

The omega−3 (n−3) polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic (DHA) acid are well known to protect against numerous metabolic disorders. In view of the alarming increase in the incidence of chronic diseases, consumer interest and demand are rapidly increasing for natural dietary sources of n−3 PUFAs. Among the plant sources, seed oils from chia (Salvia hispanica), flax (Linum usitatissimum), and garden cress (Lepidium sativum) are now widely considered to increase α-linolenic acid (ALA) in the diet. Moreover, seed oil of Echium plantagineum, Buglossoides arvensis, and Ribes sp. are widely explored as a source of stearidonic acid (SDA), a more effective source than is ALA for increasing the EPA and DHA status in the body. Further, the oil from microalgae and thraustochytrids can also directly supply EPA and DHA. Thus, these microbial sources are currently used for the commercial production of vegan EPA and DHA. Considering the nutritional and commercial importance of n−3 PUFAs, this review critically discusses the nutritional aspects of commercially exploited sources of n−3 PUFAs from plants, microalgae, macroalgae, and thraustochytrids. Moreover, we discuss issues related to oxidative stability and bioavailability of n−3 PUFAs and future prospects in these areas. [ABSTRACT FROM AUTHOR]

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Weed Research is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Assesses demographic and genetic changes in populations of Echium plantagineum. Changes in the frequency of certain alleles; Increase in the survival of individuals heterozygous at either the Pgi or Pgm loci; Detection of a consistent decline in Wright's Fixation Index values; Relative competitive abilities of the common blue-purple flowered form of E. plantagineum and of a rare pure white form.

Studies the honeybees and the nectar of Echium plantagineum L. in southeastern Australia. Analysis of stages and timing of flowering; Assessment of behavior of raindrops in the flower; Examination of aspects of floral microclimate.

The possible allergenicity of an insect pollinated weed, Echium plantagineum, was investigated in a rural area of Australia. Sixty-one subjects with respiratory allergy were studies. Positive skin test reactions to defatted ammonium bicarbonate extract of pollen were found in over 60% of subjects, and positive RAST tests in a similar number. The question of crossreactivity between weed pollens is discussed. The pollen of E. plantagineum was shown to reach the atmosphere in significant amounts about 1 month before the peak grass pollinating period. Evidence that the pollen of E. plantagineum becomes airborne and elicits an IgE response suggests that further attention should be directed to weed pollens as potential allergens. [ABSTRACT FROM AUTHOR]

This study measured the effect of livestock grazing on the seed production and the seedbank of the annual weed, Echium plantagineum L., by comparing sis sites across south-eastern Australia. Maximum taproot diameter predicted seed production of ungrazed plants irrespective of site. Seed losses to flowering plants grazed in spring were calculated using the taproot diameter relationship. Moderate continual grazing pressure throughout the seeding period (December–January) reduced seed production by at least 87%, although grazing was most destructive per unit of time in the first half of this period (peak seed production of the infestation). E. plantagineum has a strong capacity to compensate for stock grazing should the stock be removed too early. Seedbanks generally increased following significant seed rain, although this trend was not always consistent. In manipulated quadrats, where seed production was reduced by at least 90% for 4 years, germination of E. plantagineum was lower relative to controls from the second year and the seedbank was 10 times lower when measured in the fourth year. The implications of these results are discussed in relation to existing control strategies for this weed. [ABSTRACT FROM AUTHOR]