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Ecological isolation is increasingly thought to play an important role in speciation, especially for the origin and reproductive isolation of homoploid hybrid species. However, the extent to which divergent and/or transgressive gene expression changes are involved in speciation is not well studied. In this study, we employ comparative transcriptomics to investigate gene expression changes associated with the origin and evolution of two homoploid hybrid plant species, Argyranthemum sundingii and A. lemsii (Asteraceae). As there is no standard methodology for comparative transcriptomics, we examined five different pipelines for data assembly and analysing gene expression across the four species (two hybrid and two parental). We note biases and problems with all pipelines, and the approach used affected the biological interpretation of the data. Using the approach that we found to be optimal, we identify transcripts showing DE between the parental taxa and between the homoploid hybrid species and their parents; in several cases, putative functions of these DE transcripts have a plausible role in ecological adaptation and could be the cause or consequence of ecological speciation. Although independently derived, the homoploid hybrid species have converged on similar expression phenotypes, likely due to adaptation to similar habitats. [ABSTRACT FROM AUTHOR]

Phylogenetic analysis has revealed that Argyranthemum broussonetii is polyphyletic, with subsp. broussonetii (Tenerife) and subsp. gomerensis (La Gomera) resolved in separate clades within the Macaronesian endemic genus Argyranthemum. We show that A. broussonetii subsp. broussonetii and subsp. gomerensis are similar in leaf traits, likely a consequence of adaptation to similar habitats, but that the two can readily be distinguished based on capitula and cypselae characteristics. Indeed, A. broussonetii subsp. gomerensis was found to share greater affinity with A. callichrysum, also from La Gomera based on capitula and cypselae characters, in agreement with its phylogenetic placement. Therefore, we propose that A. broussonetii subsp. gomerensis should be recognized as a subspecies of A. callichrysum, specifically A. callichrysum subsp. gomerensis. A key to differentiate A. broussonetii, A. callichrysum subsp. callichrysum and subsp. gomerensis is provided. Citation: White O. W., Reyes-Betancort J. A., Chapman M. A. & Carine M. A. 2021: Recircumscription of the Canary Island endemics Argyranthemum broussonetii and A. callichrysum (Asteraceae: Anthemideae) based on evolutionary relationships and morphology. – Willdenowia 51: 129–139. Version of record first published online on 29 April 2021 ahead of inclusion in April 2021 issue. [ABSTRACT FROM AUTHOR]

Summary: Inferring the processes responsible for the rich endemic diversity of oceanic island floras is important for our understanding of plant evolution and setting practical conservation priorities. This requires an accurate knowledge of phylogenetic relationships, which have often been difficult to resolve due to a lack of genetic variation.We employed genotyping‐by‐sequencing (GBS) to investigate how geographical isolation, habitat shifts, and hybridisation have contributed to the evolution of diversity observed in Argyranthemum Webb (Asteraceae), the largest genus of flowering plants endemic to the Macaronesian archipelagos.Species relationships were resolved, and biogeographical stochastic mapping identified intra‐island speciation as the most frequent biogeographic process underlying diversification, contrary to the prevailing view in Argyranthemum and the Canary Islands. D‐statistics revealed significant evidence of hybridisation between lineages co‐occurring on the same island, however there was little support for the hypothesis that hybridisation may be responsible for the occurrence of nonmonophyletic multi‐island endemic (MIE) species.Geographic isolation, habitat shifts and hybridisation have all contributed to the diversification of Argyranthemum, with intra‐island speciation found to be more frequent than previously thought. Morphological convergence is also proposed to explain the occurrence of nonmonophyletic MIE species. This study reveals greater complexity in the evolutionary processes generating Macaronesian endemic diversity. [ABSTRACT FROM AUTHOR]

Flowering is important for plant propagation and survival, and it is also closely related to human life. Identifying the molecular mechanisms underlying flower development is essential for plant improvement and breeding. Flower development is a complex physiological process that is regulated by multiple genes. LFY genes play important roles in the floral meristem transition and act as crucial integrators in regulating the floral gene network. Argyranthemum frutescens is an ornamental species cultivated for floral displays, yet little is known about molecular mechanisms driving its flower development. In this study, the LEAFY gene homologue, AfLFY, was identified and cloned from A. frutescens, and its role and expression patterns were characterized. Two distinct copies of AfLFY were found in the A. frutescens genome and both sequences contained a 1248 bp open reading frame that encoded 415 amino acids. The putative protein sequences have a typical LFY family domain. In addition, AfLFY was expressed at the highest levels in young leaves of the vegetative stage and in the shoot apical bud meristem of the reproductive stage. Phylogenetic analysis showed that AfLFY was most closely related to DFL from Chrysanthemum lavandulifolium. Subcellular localization studies revealed that AfLFY localized to the nucleus. Heterologous expression of AfLFY in transgenic tobacco plants shortened its period of vegetative growth, converted the lateral meristems into terminal flowers and promoted precocious flowering. In addition, transgenic plants exhibited obvious morphological changes in leaf shape. qRT-PCR analysis indicated that the expression levels genes related to flowering, FT, SOC1, and AP1 were significantly upregulated in AfLFY transgenic plants. Our findings suggested that the AfLFY gene plays a vital role in promoting flowering and leaf development in A. frutescens. These results laid a foundation for us to understand the mechanism of AfLFY in regulation flowering, and the results will be helpful in improving A. frutescens through molecular breeding. [ABSTRACT FROM AUTHOR]

Well‐characterized examples of homoploid hybrid speciation (HHS) are rare in nature, yet they offer the potential to study a number of evolutionary processes. In this study, we investigate putative homoploid hybrid species in the genus Argyranthemum (Asteraceae), a group of plants endemic to the Macaronesian archipelagos of the North Atlantic Ocean. We specifically address a number of knowledge gaps surrounding the origin(s) of A. sundingii and A. lemsii, which are thought to be derived from the same parental cross. Comparisons of leaf morphology suggest that A. sundingii and A. lemsii are distinct from their parental progenitors and distinguishable from each other based on leaf area. Ecological niche modelling (ENM) demonstrated that the homoploid hybrid species occupy novel habitats that are intermediate relative to the parental species. Nuclear simple sequence repeat markers (SSRs) and single nucleotide polymorphism (SNP) data indicate that the homoploid hybrid species are distinct from the parental taxa, while population‐level sampling of chloroplast SSRs and approximate Bayesian computation show that A. sundingii and A. lemsii are independently derived from the same parental cross. As such, Argyranthemum represents an example of independent homoploid hybrid speciation events with evidence of divergence in leaf morphology and adaptation to novel intermediate habitats. On oceanic islands, which are often typified by steep ecological gradients and inhabited by recently derived species with weak reproductive barriers, multiple HHS events from the same parental cross are not only possible but also likely to have played a more important role in oceanic island radiations than we currently think. [ABSTRACT FROM AUTHOR]

Abstract: Insular woodiness refers to the evolutionary transition from herbaceousness towards derived woodiness on (sub)tropical islands and leads to island floras that have a higher proportion of woody species compared to floras of nearby continents. Several hypotheses have tried to explain insular woodiness since Darwin's original observations, but experimental evidence why plants became woody on islands is scarce at best. Here, we combine experimental measurements of hydraulic failure in stems (as a proxy for drought stress resistance) with stem anatomical observations in the daisy lineage (Asteraceae), including insular woody Argyranthemum species from the Canary Islands and their herbaceous continental relatives. Our results show that stems of insular woody daisies are more resistant to drought‐induced hydraulic failure than the stems of their herbaceous counterparts. The anatomical character that best predicts variation in embolism resistance is intervessel pit membrane thickness (TPM), which can be functionally linked with air bubble dynamics throughout the 3D vessel network. There is also a strong link between TPM vs. degree of woodiness and thickness of the xylem fibre wall vs. embolism resistance, resulting in an indirect link between lignification and resistance to embolism formation. Thicker intervessel pit membranes in Argyranthemum functionally explain why this insular woody genus is more embolism resistant to drought‐induced failure compared to the herbaceous relatives from which it has evolved, but additional data are needed to confirm that palaeoclimatic drought conditions have triggered wood formation in this daisy lineage. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

Argyranthemum frutescens (L.) Sch.Bip. and Rhodanthemum gayanum (Coss. & Durieu) B. H. Wilcox, K. Bremer & Humphries are capable of hybridization. To expand flower color variation in this intergeneric hybrid group, we performed crosses using A . frutescens as the seed parent and R . hosmariense (Ball) B. H. Wilcox, K. Bremer & Humphries, R. catananche (Ball) B. H. Wilcox, K. Bremer & Humphries as the pollen parent. One plantlet was obtained from each cross between the white to pale pink-flowered A . frutescens and white-flowered R . hosmariense , and from a cross between the pink-flowered A . frutescens and cream to pale yellow-flowered R. catananche , via ovule culture. The cross with R . hosmariense produced an individual with white to pale pink ray florets, and the cross with R . catananche produced an individual with red ray florets. The flower and leaf shape of the progenies was intermediate between the parents, and other morphological traits were also characterized in the same manner. Morphological observations and a cleaved amplified polymorphic sequence marker-based determination, using the internal transcribed spacer region as a target for amplification and the restriction enzyme Afl II, revealed that both individuals are hybrids between A . frutescens and R . hosmariense , R . catananche . To the best of our knowledge, this is the first study to report that crossbreeding between A . frutescens (seed parent) and R . hosmariense , R . catananche (pollen parent) is possible. Moreover, further development of Argyranthemum breeding, especially that of a series of hybrid cultivars with different flower colors, is expected., Competing Interests: Conflict of interestThe authors declare no conflicts of interest., (© 2023 Japanese Society for Plant Biotechnology.)

Chrysanthemum stunt viroid (CSVd) is a damaging pathogen attacking Argyranthemum plants. Our study attempted to reveal distribution patterns of CSVd in shoot apical meristems (SAM) and to explore reasons for differential ability of CSVd to invade SAM of selected Argyranthemum cultivars. Symptom development was also observed on greenhouse-grown Argyranthemum plants. Viroid localization using in situ hybridization revealed that the ability of CSVd to invade SAM differed among cultivars. In diseased ‘Yellow Empire’ and ‘Butterfly’, CSVd was found in all tissues including the uppermost cell layers in the apical dome and the youngest leaf primordia 1 and 2. In diseased ‘Border Dark Red’ and ‘Border Pink’, CSVd was detected in the lower part of the apical dome and elder leaf primordia, leaving the upper part of the apical dome, and leaf primordia 1 and 2 free of viroid. Histological observations and transmission electron microscopy showed similar developmental patterns of vascular tissues and plasmodesmata in the SAMs of ‘Yellow Empire’ and ‘Border Dark Red’, while immunolocalization studies revealed a major difference in the number of callose (β -1, 3-glucan) particles deposited at plasmodesmata in SAM. A lower number of callose particles were found deposited at plasmodesmata of SAM of ‘Yellow Empire’ than ‘Border Dark Red’. This difference is most likely responsible for the differences in ability of CSVd to invade SAM among Argyranthemum cultivars.

Chrysanthemum stunt viroid (CSVd) can infect Argyranthemum and cause serious economic loss. Low temperature treatment combined with meristem culture has been applied to eradicate viroids from their hosts, but without success in eliminating CSVd from diseased Argyranthemum. The objectives of this work were to investigate (1) the effect of low temperature treatment combined with meristem culture on elimination of CSVd, (2) the effect of low temperature treatment on CSVd distribution pattern in shoot apical meristem (SAM), and (3) CSVd distribution in flowers and stems of two infected Argyranthemum cultivars. After treatment with low temperature combined with meristem tip culture, two CSVd-free plants were found in 'Border Dark Red', but none in 'Yellow Empire'. With the help of in situ hybridization, we found that CSVd distribution patterns in the SAM showed no changes in diseased 'Yellow Empire' following 5°C treatment, compared with non-treated plants. However, the CSVd-free area in SAM was enlarged in diseased 'Border Dark Red' following prolonged 5°C treatment. Localization of CSVd in the flowers and stems of infected 'Border Dark Red' and 'Yellow Empire' indicated that seeds could not transmit CSVd in these two cultivars, and CSVd existed in phloem. Results obtained in the study contributed to better understanding of the distribution of CSVd in systemically infected plants and the combination of low temperature treatment and meristem tip culture for production of viroid-free plants. [ABSTRACT FROM AUTHOR]

Field performance evaluation and genetic integrity assessment were conducted in Argyranthemum plants derived from cryopreserved shoot tips. Some variations in root formation and vegetative growth were found in the plants following cryopreservation, but morphologies of the leaves and flowers, and color, number and size of the flowers remained unchanged in the plants recovered from cryopreservation, compared with the control. Assessments of genetic integrity by the two molecular markers: inter simple sequence repeat (ISSR) and amplified fragment length polymorphism (AFLP) did not detect any polymorphic bands across the plants tested following cryopreservation. These data indicate that cryopreservation reduces, to a certain degree, root formation and vegetative growth, but it does not alter morphologies of leaves and flowers, may not cause any genetic alternations, and has no adverse effects on quantity and quality of the flowers. Therefore, the droplet vitrification cryopreservation can be considered promising for long-term preservation of Argyranthemum germplasm. [ABSTRACT FROM AUTHOR]

Phytoplasmas are cell wall-less microorganisms associated with plant diseases worldwide. Many important food, vegetable and fruits crops as well as ornamental plants can be severely affected by these pathogens, with significant economic impacts. Phytoplasma diseases of ornamentals have been described worldwide in a wide range of plant genera, and 11 different 16Sr groups have been identified. In Italy, many ornamental plant species belonging to several botanical families have been found to be infected by phytoplasmas, classified into the ribosomal groups 16SrI, 16SrII, 16SrV and 16SrXII. During a survey carried out in commercial gardens in Rome, some marguerite daisy (Argyranthemum frutescens) plants showing symptoms of phytoplasma-like disease, were collected and submitted to molecular analyses. Cloning and sequencing of the portion of the 16S rRNA gene followed by BLAST analysis, real and virtual restriction fragment length polymorphism anlaysis with AluI and RsaI, allowed assignment of the detected phytoplasma to the 16SrIX-C group (Picris echioides yellows, PEY). [ABSTRACT FROM AUTHOR]

Chrysanthemum is one of important ornamental species in the world. Its highly heterozygous state complicates molecular analysis, so it is of interest to derive haploid forms. A total of 2579 non-fertilized chrysanthemum ovules pollinated by Argyranthemum frutescens were cultured in vitro to isolate haploid progeny. One single regenerant emerged from each of three of the 105 calli produced. Chromosome counts and microsatellite fingerprinting showed that only one of the regenerants was a true haploid. Nine doubled haploid derivatives were subsequently generated by colchicine treatment of 80 in vitro cultured haploid nodal segments. Morphological screening showed that the haploid plant was shorter than the doubled haploids, and developed smaller leaves, flowers, and stomata. An in vitro pollen germination test showed that few of the haploid's pollen were able to germinate and those which did so were abnormal. Both the haploid and the doubled haploids produced yellow flowers, whereas those of the maternal parental cultivar were mauve. Methylation-sensitive amplification polymorphism (MSAP) profiling was further used to detect alterations in cytosine methylation caused by the haploidization and/or the chromosome doubling processes. While 52.2% of the resulting amplified fragments were cytosine methylated in the maternal parent's genome, the corresponding proportions for the haploid's and doubled haploids' genomes were, respectively, 47.0 and 51.7%, demonstrating a reduction in global cytosine methylation caused by haploidization and a partial recovery following chromosome doubling. [ABSTRACT FROM AUTHOR]

Four complete water-soluble fertilizer (WSF) formulations including micro-nutrients applied at 200 mg⋅L-1 nitrogen (N) at each irrigation [Peters Excel (21N-2.2P-16.5K), Daniels (10N-1.8P-2.5K), Peters Professional (15N-1.3P-20.8K), and Jack's Professional (20N-1.3P-15.7K)] were compared with two controlled-release fertilizer (CRF) products (also containing micronutrients) substrate incorporated at transplant at a rate of 3000 g⋅m-3 of substrate [Osmocote Plus (15N-4P-9.9K, 90 to 120 days longevity at 21 °C) and Osmocote Bloom (12N-3.1P-15K, 60 to 90 days longevity at 21 °C) in the greenhouse production of four commonly produced bedding plant species with high alkalinity irrigation water (pH 7.1, 280 mg⋅L-1 CaCO3 equivalent). Species included Argyranthemum frutescens (L.) Sch. Bip. 'Madeira Cherry Red' and iron-inefficient Calibrachoa Cerv. hybrid 'Cabaret Pink Hot', Diascia barberae Hook. f. 'Wink Coral', and Sutera cordata Roth 'Abunda Giant White'. Additional treatments included a combination of 100 mg⋅L-1 Excel and 2100 g⋅m-3 Osmocote Plus and an Osmocote Plus treatment irrigated with reduced alkalinity water (acidified to pH 6.3, 92 mg⋅L-1 CaCO3 equivalent). Bedding plants were evaluated at the end of a finish or market stage (3 or 5 weeks depending on species) for shoot dry mass (SDM) and root dry mass (RDM), tissue nutrient concentrations, and visual quality rating (0 to 4). At 3 weeks, there were no significant differences in SDM and RDM between fertilizer treatments for any of the four species. Shoot dry mass significantly increased at 5 weeks in the WSF and combination treatments over the three CRF only treatments for Argyranthemum and over the non-acidified Osmocote Plus treatment only for Calibrachoa. At finish, 3 weeks for Sutera and Diascia and 5 weeks for Argyranthemum and Calibrachoa, visual quality rating for all species was lowest when using Osmocote Plus with or without acidified irrigation water compared with the WSF treatments, except the Daniels treatment in Argyranthemum, which also resulted in a low visual quality rating. Leaf tissue N for all species and phosphorus (P) for all except Diascia were below the recommended range for bedding plant crops in the CRF treatments, which was reflected by the lower substrate electrical conductivity (EC) for the CRF alone and combination treatments. Leaf tissue N and P were related to visual quality rating for all species, leaf tissue potassium (K) for Argyranthemum and Calibrachoa only, and leaf tissue iron (Fe) for Diascia only. [ABSTRACT FROM AUTHOR]

Chrysanthemum stunt viroid (CSVd) is a quarantine pathogen for chrysanthemum (Dendranthema spp.) in the European countries (Plant Health Directive 2000/29/EC), because this host is severely affected, thus comes down with a disease characterized by stunting, leaf chlorosis and floral disorders. CSVd spread in Europe has efficiently been restrained so far, although several outbreaks were recorded in the past. Here we report the first occurrence of CSVd in Italy, as detected in several symptomless cultivars of Argyranthemum frutescens (marguerite daisy) by RT-PCR with specific primers and by Northern blot hybridization with a specific digoxigenin-labeled riboprobe. Viroid identity was ultimately ascertained by cloning and sequencing cDNA amplicons. Molecular characterization of CSVd isolates from six different A. frutescens cultivars disclosed viroid RNA populations with a prevalent size of 354 nt and sequences 98-100% identical to those of CSVd variants reported previously from D. grandiflora and A. frutescens. These results call for a prompt extension of surveys for assessing the presence of CSVd in symptomless A. frutescens and other ornamentals, which could constitute hidden reservoirs of this pathogen. In view of this, a tissue-printing hybridization method for detecting CSVd in A. frutescens was tested and validated. [ABSTRACT FROM AUTHOR]

Cuttings of herbaceous annual bedding plants must be rooted in late winter and early spring when ambient outdoor photosynthetic daily light integrals (DLIs) are at seasonally low levels. We evaluated the effect of DLI during root development on growth, morphology, and quality of nine popular vegetatively propagaled annual bedding plant species. Cuttings of Angelonia angustifolia Benth. 'AngeIMist White Cloud', Argyranthemum frutescens (L.) Sch. Bip. 'Madeira Cherry Red', Diascia barberae Hook. f. 'Wink Coral', Lantana camara L. 'Lucky Gold', Nemesiafruticans (Thunb.) Benth. 'Aromatica Royal', Osteospermum ecklonis (DC.) Norl. 'Voltage Yellow', Scaevola L. hybrid 'Blue Print', Sutera cordata Roth. 'Abunda Giant White', and Verbena Ruiz x hybrida 'Aztec Violet' wer harvested and propagated in a glass-glazed greenhouse with 23 °C air and substrate temperature set points. After callusing (≈5 mol⋅m-2⋅d-1 for 7 days), cuttings of each species were placed under one of three different fixed-woven shade cloths providing ≈38%, 61%, or 86% shade or no shade with 16 h of supplemental light for 14 days. There were no clear trends across species for stem length in response to DLI. Stem caliper of Arg), ranthemum, Diascia, and Nemesia increased by 35%, 119%, and 89%, respectively, as DLI increased from 1.2 to 12.3 mol⋅m-2⋅d-1. Depending on species, total, shoot, and root dry mass increased by 64% to 465%, 50% to 384%, and 156% to 1137%, respectively, as DLI increased from 1.2 to 12.3 mol⋅m-2⋅d-1. The quality index, an objective, integrated, and quantitative measurement of rooted cutting quality, increased for all species by 176% to 858% as DLI increased from 1.2 to 12.3 mol⋅m-2⋅d-1. Our results indicate that providing a DLI of ≈,8 to 12 mol⋅m-2⋅d-1 after callusing increases both growth and quality of rooted cuttings. [ABSTRACT FROM AUTHOR]

Abstract: Argyranthemum frutescens is a commercially important ornamental species with extensive breeding programmes in several countries. Since it is vegetatively propagated there is a great need for tools for identification of cultivars. Vegetatively propagated species require clean-up from diseases, often performed through meristem-tip cultures. Forty-three cultivars of A. frutescens propagated by meristem-tip culture and traditional cuttings were analyzed for genetic relatedness and possible somaclonal variation using AFLP. Five primer combinations resulted in a relatively high degree of polymorphism. Ten molecular markers generated by one primer combination could distinguish between all 43 cultivars. Differences in fingerprints between meristem-tip culture and cuttings from the same cultivars were found, but the proportion of fragments being specific for either tissue culture or cuttings was relatively low. Some cultivars that did not display somaclonal variation as judged by the AFLP-fingerprints may still be genetically unstable since some morphological variation was observed in the true to type test. [Copyright &y& Elsevier]

Abstract: Ferredoxins are proteins that participate in photosynthesis and in other processes that require reducing equivalents, such as the reduction of nitrogen or fatty acid desaturation. Two classes of ferredoxins have been described in plants: light-regulated photosynthetic ferredoxins and heterotrophic ferredoxins whose activity is not influenced by light. Genes encoding the two forms of ferredoxin have been cloned and characterized in developing sunflower cotyledons. Here, these genes were overexpressed in Escherichia coli and they were purified by ion exchange and size exclusion chromatography to study their capacity to supply electrons to two different sunflower desaturases: soluble stearoyl-ACP desaturase from sunflower cotyledons, and membrane bound desaturase FAD7 expressed in yeast. In both cases photosynthetic ferredoxin was the form that promoted the strongest desaturase activity. [Copyright &y& Elsevier]

We conducted a pot trial to investigate the effects of soil cadmium (Cd) content, soil pH, soil type and soil chloride (Cl−) content on Cd uptake by garland chrysanthemum ( Chrysanthemum coronarium cv. Kiwame-Cyuba) to improve predictions of plant Cd uptake. We concluded that predictions of plant Cd uptake should involve the following two procedures: (i) predicting the Cd concentration of the soil solution as a function of the chemical properties of the soil, (ii) predicting plant Cd uptake as a function of the Cd concentration in the soil solution. A unique hyperbolic relationship was observed between plant Cd uptake and total Cd concentration in the soil solution. The relationship was independent of soil type, soil Cd content and salinity treatment, and was explained by: UCd =  Vp[CdT] + { Vmax[CdT]/ Km + [CdT]}, where UCd represents plant Cd uptake, [CdT] represents the total Cd concentration of the soil solution, and Vp, Vmax and Km are constants. The Cd adsorption kinetics were investigated using the “monodentate coordination model,” which enabled Cd2+ activity in the soil solution to be explained by: log(Cd2+) = log  Kmon + log  QCd –  pH – log  CCd, where Kmon represents the equilibrium constant of Cd adsorption, (Cd2+) represents Cd2+ activity, Qcd represents the amount of Cd adsorbed, and CCd represents the Cd adsorption capacity. The total Cd concentration in the soil solution showed a linear correlation with the Cl− concentration in the soil solution. The effect of Cl−salinity on the total Cd concentration in the soil solution was attributed to the formation of a cadmium–chloride complex (CdCl+). For a more robust prediction of plant Cd uptake, there is a clear need for a simple method that can simultaneously determine the soil Cd concentration, the coefficient constant for Cd adsorption and the Cd adsorption capacity of the soil. [ABSTRACT FROM AUTHOR]

The genus Helichrysum has 500-600 species in Africa, Madagascar, the Mediterranean basin, Macaronesia, western and central Asia, and India. The aims of this study are to confirm the exclusion of Castroviejoa from Helichrysum, to elucidate the origin of the Macaronesian endemics, to confirm the monophyly of the Mediterranean-Asiatic group, and, within this group, to contrast molecular data with sectional classification and to provide insight into trends in character evolution and biogeography. To address these issues, ITS and ETS sequences were used in phylogenetic analyses. Results show that Castroviejoa is excluded from Helichrysum. The phylogeny obtained suggests a southern African origin for Helichrysum and several subsequent migrations throughout the African continent. The species from the Canary Islands do not form a monophyletic clade, suggesting that at least two independent colonization events occurred. Helichrysum makranicum, from Oman and southern Iran, is the closest relative of a clade consisting of two endemics of the Canary Islands, providing new evidence of the phytogeographical links between Macaronesia and eastern Africa-southern Arabia. Helichrysum gossypinum, the third endemic of the Canary Islands, is the sister species of a monophyletic Mediterranean and Asiatic group, with the four endemics of Madeira sister to all of them.Within the Mediterranean-Asiatic clade, sect. Stoechadina is monophyletic, but sect. Helichrysum and sect. Virginea are not. Once in the Mediterranean region, the genus is hypothesized to have diversified and expanded to the east up to western and central Asia and to have suffered a reduction in woodiness. [ABSTRACT FROM AUTHOR]

Abstract: The capitula of Cynara cardunculus contain hairs and pappi representing 7% of the total plant biomass. These low density biomass components could be mechanically separated without apparent losses using a whole-plant processing prototype. Hairs and pappi are filamentous structures made up of longitudinally aligned fibre cells, without intercellular voids or pitting, with the following dimensions regarding length, width and wall thickness: 1.35mm, 19.8, and 4.8μm for hairs and 1.78mm, 10.4, and 2.9μm for pappi. Chemically hairs and pappi have low content of ash (1.9% and 1.1%, respectively), extractives (5.4% and 6.0%) and lignin (10.6% and 17.8%), and high content of holocellulose (77.5% and 72.8%) and α-cellulose (55.2% and 46.8%). Pulps could be produced using a conventional kraft process with high yields and low residual lignin, e.g. 63% at Kappa 7 for hairs and 48% at Kappa 11 for pappi, low coarseness values (0.04 and 0.03mgm−1) and adequate pulp properties for paper (40 and 42Nmg−1 tensile index; 3.6 and 3.4kPam2 g−1 burst index in unrefined pulps of hairs and pappi, respectively). The results also indicated that there is scope for improving pulp quality by optimising pulping conditions to this type of new raw materials. The differences between hairs and pappi may also be further exploited namely the lower lignin content of hairs and the higher slenderness and wall thickness of pappi fibres. The utilization of hairs and pappi may strengthen the differentiated use of biomass fractions of the Cynara plant and its potential as a bioenergy crop. [Copyright &y& Elsevier]

Examples of recurrent homoploid hybrid speciation are few. One often-cited example is Argyranthemum sundingii. This example includes two described species, A. lemsii and A. sundingii, resulting from reciprocal hybridization between A. broussonetii and A. frutescens on Tenerife. The four species and artificial F1 and F2 hybrids have previously been investigated morphologically and cytologically. Here, we examine population differentiation based on amplified fragment length polymorphism to get a better understanding of the genetic relationships among the species and the extent of hybridization. We aim to investigate if there is molecular support for treating the hybrid species as one taxon. Seven parental and four hybrid species populations (149 individuals) were analysed and we scored 85 polymorphic markers. A few (2–5) were private to each species but variably present and mostly rare. Our principal coordinate, STRUCTURE and BAPS analyses and AMOVA resulted in a clear separation of the parental species. The hybrid species were genetically less divergent but not identical. Our data indicate that hybridization and introgression are common in all these species on Tenerife and support the hypothesis that homoploid hybrid speciation has occurred repeatedly. Intrinsic post-zygotic barriers are notoriously weak in Argyranthemum and reproductive isolation and speciation result primarily from strong ecological selection. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 19–31. [ABSTRACT FROM AUTHOR]

ABSTRACTSeveral studies have reported biological effects of Mikania glomerataand Mikania laevigata, used in Brazilian folk medicine for respiratory diseases. Pneumoconiosis is characterized by pulmonary inflammation caused by coal dust exposure. In this work, we evaluated the effect of pretreatment with M. glomerataand M. laevigataextracts (MGE and MLE, respectively) (100 mg/kg, s.c.) on inflammatory and oxidative stress parameters in lung of rats subjected to a single coal dust intratracheal instillation. Rats were pretreated for 2 weeks with saline solution, MGE, or MLE. On day 15, the animals were anesthetized, and gross mineral coal dust or saline solutions were administered directly in the lung by intratracheal instillation. Fifteen days after coal dust instillation, the animals were killed. Bronchoalveolar lavage (BAL) was obtained; total cell count and lactate dehydrogenase (LDH) activity were determined. In the lung, myeloperoxidase activity, thiobarbituric acid-reactive substances (TBARS) level, and protein carbonyl and sulfhydryl contents were evaluated. In BAL of treated animals, we verified an increased total cell count and LDH activity. MGE and MLE prevented the increase in cell count, but only MLE prevented the increase in LDH. Myeloperoxidase and TBARS levels were not affected, protein carbonylation was increased, and the protein thiol levels were decreased by acute coal dust intratracheal administration. The findings also suggest that both extracts present an important protective effect on the oxidation of thiol groups. Moreover, pretreatment with MGE and MLE also diminished lung inflammatory infiltration induced by coal dust, as assessed by histopathologic analyses. The present study indicates that M. glomerataand M. laevigatamight become good candidates for the prevention of lung oxidative injury caused by coal dust exposure. [ABSTRACT FROM AUTHOR]

Banker plants with Aphidius colemani Viereck were tested in greenhouses in Massachusetts and New York for control of cotton aphid Aphis gossypii Glover, and green peach aphid Myzus persicae (Sulzer) on 2 spring flower crops, pansies (Viola tricolor hortensis) and Marguerite daisies (Argyranthemum hybrid). Banker plants consisted of pots of barley plants infested with the bird cherry-oat aphid Rhopalosiphum padi (L.), inoculated at the start of the crop with adults of A. colemani purchased from a commercial insectary. Initial trials were conducted in University of Massachusetts greenhouses containing flats of the crop plants. Sentinel plants in flats were infested uniformly with aphids, and particular greenhouses were subjected to the presence of banker plants or left as controls. Prior to University trials, a survey was conducted in commercial greenhouses in Massachusetts and New York to determine the frequency and species of aphid infestation in spring flower crops. After University trials, the efficacy of banker plants was tested in commercial greenhouses in both states. In surveys of commercial greenhouses, M. persicae was the most frequently detected species, accounting for 53% of all infestations. In University greenhouse trials, in absence of parasitism, A. gossypii increased fastest on daisy, followed by M. persicae on daisy, M. persicae on pansy, and A. gossypii on pansy. Parasitoid suppression of population increase was strongest for A. gossypii on daisy and poorest for M. persicae on pansy. The presence of 2 aphid species in the same greenhouse did not alter the level of biological control in our trial. In commercial greenhouses, banker plants failed to control M. persicae deployed on infested pansies as sentinel hosts. In the laboratory, a 12-h exposure to dried residues of pyriproxyfen or pymetrozine, insecticides commonly used to control aphids, reduced survival of A. colemani adults, compared to a water control (82% survival), to 71% and 53%, respectively. Adult parasitoid emergence from pesticide-treated aphid mummies was reduced from 68% for the controls to 56% for pyriproxyfen and 62% for pymetrozine. [ABSTRACT FROM AUTHOR]

In this article, low temperature and its degradative influence on the material together with hygro-thermal effect are highlighted. Hygrothermal factor is a major environmental factor experienced by the composites. An attempt has been made to study the mechanical properties of bidirectional glass cloth specimens exposed to low temperature and humid condition. Tensile strength records its highest value after 10 days exposure at -55°C, compressive strength at 0°C exposure increases but after 10 days exposure at -55°C decreases, shear strength of exposed specimen at 0°C increases, flexural strength of exposed specimen at -55°C increases and records its highest value of 10 days exposed specimen. Further, it has been observed that the strength of the composite is in the following order: Compressive strength of specimen

Abstract: The present study describes the synthesis of a novel class of vesicle-forming bolaamphiphiles with choline ester head groups. These bolaamphiphiles were derived from vernonia oil, whose main constituent is vernolic acid, a fatty acid with a unique combination of epoxy, carboxy and unsaturated double bonds. A series of bolaamphiphiles containing amido or ester groups within the hydrophobic domain were synthesized from N,N′-alkylenebis (vernolamides) and α,ω-alkylene divernolate ester in a two-stage synthesis comprising opening of the epoxy ring with chloroacetic acid, followed by quaternization with N,N-dimethylaminoethyl acetate to form choline ester head groups. The products were characterized by FT-IR, 1H and 13C NMR, and ESI-MS. Vesicles prepared from these bolaamphiphiles have the potential to serve as a targeted drug delivery systems with selective decapsulation in the presence of the enzyme acetylcholine esterase, resulting in site-specific release of the drug. [Copyright &y& Elsevier]

The paper presents a list of non-native invasive plants in the Arad county (West Romania). For each of 10 found species, the authors mention the main biological, ecological, and chorological traits, as well as their populations locations in the Arad county. These data combines informations from scientific references and original results. It is mentioned that the most infested area in the Arad county is the Mureş Valley. For some species like Ambrosia artemisiifolia, Xanthium strumarium subsp. italicum and Amorpha fruticosa specific management measures should be taken. [ABSTRACT FROM AUTHOR]

The pathogenicity of five isolates of Fusarium oxysporum obtained from infected gerbera ( Gerbera jamesonii), chrysanthemum ( Chrysanthemum morifolium), Paris daisy ( Argyranthemum frutescens) and African daisy ( Osteospermum sp.) plants was tested on some varieties of the following Compositae hosts: C. morifolium, G. jamesonii, Argyranthemum frutescens (Paris daisy) and Osteospermum sp. and compared with the host range and pathogenicity of an isolate of F. oxysporum f. sp. chrysanthemi obtained from the ATCC collection. The results indicated that isolates of F. oxysporum from G. jamesonii as well as those from A. frutescens and Osteospermum sp. belong to the forma specialis chrysanthemi. The isolate from gerbera was virulent on all tested varieties of gerbera, C. morifolium, A. frutescens and Osteospermumsp. Similar results were obtained testing the isolates obtained from A. frutescens and Osteospermumsp. The strain from C. morifolium infected cultivar of gerbera, A. frutescens and Osteospermum sp. The pathogenicity of isolate of F. oxysporum f. sp. chrysanthemi obtained from the ATCC showed a different cultivar range particularly in the case of chrysanthemum and gerbera. [ABSTRACT FROM AUTHOR]

Programmed cell death (PCD) was studied in the petals of Antirrhinum majus, Argyranthemum frutescens, and Petunia hybrida, using DNA degradation and changes in nuclear morphology as parameters. The petals exhibit loss of turgor (wilting) as a visible symptom of PCD. DNA degradation, as shown on agarose gels, occurred in all species studied, prior to visible wilting. The number of DNA masses in all the petals of a flower, determined by flow cytometry, markedly increased in Argyranthemum and Petunia, but decreased in Antirrhinum. Many small DNA masses were observed in Argyranthemum and Petunia. The surface of each small DNA mass stained with the lipophilic fluorochrome 3,3′-dihexyloxacarbocyanine iodide (DiOC6), indicating that these masses were surrounded by a membrane. In Antirrhinum, in contrast, the chromatin fragmented into several small spherical clumps that remained inside a large membranous structure. Nuclear fragmentation, therefore, did not occur in Antirrhinum, whereas nuclear fragmentation possibly was a cause of the small DNA masses in Argyranthemum and Petunia. It is concluded that at least two contrasting nuclear morphologies exist during PCD. In the first, the chromatin fragments inside the nucleus, not accompanied—or followed—by nuclear fragmentation. In the second, a large number of DNA masses were observed each enveloped by a membrane. The second type was probably due, at least partially, to nuclear fragmentation. [ABSTRACT FROM PUBLISHER]

Stock plants of four vegetatively propagated annual species (Argyranthemum frutescens 'Comet Pink', Nemesia fruticans 'Plum Sachet' Venten., Osteospermum fruticosum 'Zulu' L., and Verbena xhybrida 'Lanai Bright Pink' L.) were grown with one (P), two (PP), or three (PPP) pinches during the scaffold development phase. The number of pinches applied to all four species affected the yield and distribution of cuttings produced over time. P began to produce cuttings first; however, the rate (number of cuttings per week) of cutting production was relatively low resulting in the fewest total cuttings produced by the end of the experiment. Cutting harvest from PPP started 3 to 6 weeks after cuttings were initially harvested from P. However, the rate of increase in cutting production was greater in PPP than P for all species, except Osteospermum, so the total cutting yield of PPP equaled P after 3 to 5 weeks of cutting production. The final cutting yield for PPP was 38%, 38%, 20%, and 8% higher than P for Argyranthemum, Nemesia, Osteospermum, and Verbena, respectively. PP produced 24%, 17%, and 21% more total cuttings than P for Argyranthemum, Nemesia, and Osteospermum, respectively, while Verbena displayed no significant difference. At the termination of the experiment, the weekly rate of cutting production increased 66.3%, 84.0%, and 30.5% as pinch number increased from P to PPP for Argyranthemum, Nemesia, and Verbena, respectively. This study demonstrates that the number of pinches performed on stock plants during scaffold development can have a significant impact on the timing, the weekly production rate, and cumulative yield of cuttings harvested. [ABSTRACT FROM AUTHOR]

Two diploid species of hybrid origin, Argyranthemum lemsii and A. sundingii, have been described from different valleys in the Anaga peninsula, north-east Tenerife. They have previously been shown to originate from hybridization between the same parental species, the montane A. broussonetii and the coastal A. frutescens, A. broussonetii being the chloroplast donor in one valley and A. frutescens in the other. The specific status of the two hybrid species has been questioned. In this study we used karyotype analysis, FISH, and GISH to address the question of multiple diploid hybrid speciation. GISH did not discriminate clearly between the parental genomes, but differential labelling was observed in separate hybrid populations, indicating different chromosomal rearrangements in different valleys. Small karyotype differences and local loss of rDNA were also observed. Thus separate origins of the same hybrid combination in different valleys in Tenerife have been verified. Our results add some support to the recognition of two species of hybrid origin, but the case serves to illustrate some of the many problems connected with the species concept in plants. [ABSTRACT FROM AUTHOR]

Results of aimed patch testing with constituents of sesquiterpene lactone (SL) mix, Compositae mix (CM) and other Compositae extracts and allergens in 190 Compositae-allergic patients detected in an 8-year period are presented. Feverfew of CM elicited positive reactions most frequently, followed by tansy, wild chamomile, yarrow and arnica, whereas dehydrocostus lactone of SL was the most frequent elicitor of positive reactions, followed by alantolactone and costunolide. Chrysanthemum (Dendranthema) and marguerite (Argyranthemum frutescens) were the most important suspected sensitizers in both occupationally and nonoccupationally exposed, and cross-reactions between chrysanthemum and feverfew/tansy/chamomile may partly explain the high prevalence of positive reactions to the 3 last mentioned. In the nonoccupationally sensitized group, garden plants such as feverfew, blanket flower (Gaillardia), elecampane (Inula helenium), large yellow ox-eye (Telekia speciosa) and cosmea (Cosmos) were additional important allergenic plants. The 3 last mentioned were picked up by SL mix. Most of the lettuce-sensitized persons were CM-positive. 19% of the occupationally sensitized group were negative to both SL and CM, making very aimed patch testing necessary, notably when suspecting rare sensitizers such as Gerbera and star of the veldt (Osteospermum). The significance of the weeds dandelion, dog fennel and ox-eye daisy as sensitizers is not clarified, but they are probably less important than cultivated plants. [ABSTRACT FROM AUTHOR]

There are several well-documented examples of multiple hybrid origins of polyploid species. Herein we report the first, to our knowledge, explicit example of a species that most probably has originated recurrently by diploid hybrid speciation. Genetic relationships and stabilization of two Argyranthemum populations of putative hybrid origin on Tenerife, the Canary Islands, were investigated using chromosomal, morphometric, and fertility analyses of cultivated progeny families and artificial F1 and F2 hybrids. These data were compared to a recently published chloroplast DNA phylogeny of the genus, in which the same populations were included. The results suggest that the two populations must be referred to a single species, A. sundingii, which is diploid, fully fertile, genetically stabilized, and occurs in an ecologically intermediate habitat opened by deforestation, and that this species has originated at least twice following local hybridization in two valleys. The same parental species were involved in each origin; the montane A. broussonetii and the coastal A. frutescens. The montane species was the chloroplast donor in one of the valleys and the coastal species in the other. [ABSTRACT FROM AUTHOR]