Chemical Constituents of Plants from the Genus Eupatorium (1904–2014)

Eupatorium (family: Compositae), which comprises nearly 1200 species, is distributed throughout tropical America, Europe, Africa, and Asia. Up to now, the reported constituents from the genus Eupatorium involve flavonoids, terpenoids, pyrrolizidine alkaloids, phenylpropanoids, quinonoids, essential oils, and some others, altogether more than 300 compounds. Studies have shown that Eupatorium and its active principles possess a wide range of pharmacological activities, such as cytotoxic, antifungal, insecticidal, antibacterial, anti‐inflammatory, and antinociceptive activities. Currently, effective monomeric compounds or active parts have been screened for pharmacological activities from Eupatorium in vivo and in vitro. Increasing amount of data supports application and exploitation for new drug development.     

Neue sesquiterpenlactone und andere inhaltsstoffe aus vertretern der Eupatorium-gruppe

The investigation of twelve further species of the Eupatorium complex affords four new germacrolides and seven guaianolides together with new thymol and p-hydroxyacetophenone derivatives. The structures of these compounds have been elucidated by spectroscopic methods. Chemotaxonomic aspects of these findings are briefly discussed.     

Comparative Analysis and Identification of miRNAs and Their Target Genes Responsive to Salt Stress in Diploid and Tetraploid Paulownia fortunei Seedlings

Salt stress is a global environmental problem that affects plant growth and development. Paulownia fortunei is an adaptable and fast-growing deciduous tree native to China that is environmentally and economically important. MicroRNAs (miRNAs) play important regulatory roles in growth, development, and stress responses in plants. MiRNAs that respond to biotic stresses have been identified; however, how miRNAs in P. fortunei respond to salt stress has not yet been reported. To identify salt-stress-responsive miRNAs and predict their target genes, four small RNA and four degradome libraries were constructed from NaCl-treated and NaCl-free leaves of P. fortunei seedlings. The results indicated that salt stress had different physiological effects on diploid and tetraploid P. fortunei. We detected 53 conserved miRNAs belonging to 17 miRNA families and 134 novel miRNAs in P. fortunei. Comparing their expression levels in diploid and tetraploid P. fortunei, we found 10 conserved and 10 novel miRNAs that were significantly differentially expressed under salt treatment, among them eight were identified as miRNAs probably associated with higher salt tolerance in tetraploid P. fortunei than in diploid P. fortunei. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to predict the functions of the target genes of the conserved and novel miRNAs. The expressions of 10 differentially expressed miRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). This is the first report on P. fortunei miRNAs and their target genes under salt stress. The results provided information at the physiological and molecular levels for further research into the response mechanisms of P. fortunei to salt stress.     

Freshwater invasibility level depends on the population age structure of the invading mussel species

Environmental conditions may affect invasibility and potentially prevent successful invasions of the freshwater bivalve Limnoperna fortunei Dunker, 1857. However, even though the larval stage may be considered an important species’ characteristic, the invasion processes of L. fortunei are mainly evaluated using only the adult stage. Therefore, the aim of this study was to identify what, and how, environmental filters might predict the likelihood of occurrence of each of the L. fortunei larval stages. Logistic regressions were applied using the larval stages of L. fortunei as a surrogate of population age structure and the environmental variables as the main filters that potentially predicted the likelihood of the occurrence of each larval stage of L. fortunei. The turbidity predicted the occurrence of the D-shaped larvae and straight-hinged veliger stages, while the umbonated-veliger and pediveliger stages were predicted by the pH and conductivity. Finally, the phytoplankton density (diatoms) predicted the occurrence of the umbonated-veliger, pediveliger and mainly the plantigrade stages. Our findings suggested that, during larvae development, from younger to older stages, the main environmental predictor of larvae occurrence shifted from abiotic to biotic variables, indicating that larval stages are indeed an important factor that helps in the evaluation of freshwater invasibility. These findings are particularly important for floodplain systems, where flood pulse dynamics may increase propagule pressure, leading to a successful spread among habitats. Then, even though environmental filters were important to predict successful invasions, we highlight that a successful invasion might depend on the population age structure of the invading species arriving in the new habitat. Thus, successful L. fortunei invasions in floodplain systems may depend on the interaction between invasiveness, invasibility and propagule pressure.     

The role of water-water cycle in regulating the redox state of photosystem I under fluctuating light

The regulation of photosystem I (PSI) redox state under fluctuating light was investigated for four species using P700 measurement and electrochromic shift analysis. Species included the angiosperms Camellia japonica, Bletilla striata and Arabidopsis thaliana and the fern Cyrtomium fortunei. For the first seconds after transition from low to high light, all species showed relatively low levels of the proton gradient (ΔpH) across the thylakoid membranes. At this moment, PSI was highly oxidized in C. japonica and C. fortunei but was over-reduced in B. striata and A. thaliana. In B. striata and A. thaliana, the redox state of PSI was largely dependent on ΔpH. In contrast, the rapid oxidation of P700 in C. japonica was relatively independent of ΔpH, but was mainly dependent on the outflow of electrons to O₂ via the water-water cycle. In the fern C. fortunei, PSI redox state was rapidly regulated by the fast photo-reduction of O₂ rather than the ΔpH. These results indicate that mechanisms regulating PSI redox state under fluctuating light differ greatly between species. We propose that the water-water cycle is an important mechanism regulating the PSI redox state in angiosperms.     

Studies in eupatorium (Compositae), III. Apparent wind pollination

Eupatorium is a large, chiefly American genus in which some species have deviated from the usual reproductive methods of insect pollination and outcrossing. Apomixis and autogamy are two reproductive specializations which have been reported previously. A third, anemophily, is suspected inE. solidaginifolium, E. solidaginoides, E. monanthum, and several other species. Our assumptions are based upon morphological modifications of the inflorescence, anther appendages, style branches, and pollen. Wind pollination in the Compositae has heretofore been known only in the tribe Anthemideae and the subtribe Ambrosinae of the Heliantheae; its occurrence inEupatorium is an independent evolutionary event. The occurrence of apomixis, autogamy, and anemophily in members ofEupatorium from the same geographical region probably represents (at least in part) correlated responses to the same environmental stress, a scarcity of insect pollinators.     

Non-native liana, <Emphasis Type="Italic">Euonymus fortunei</Emphasis>, associated with increased soil nutrients,unique bacterial communities,and faster decomposition rate

Invasive plants have wide-ranging impacts on native systems including reducing native plant richness and altering soil chemistry, microbes, and nutrient cycling. Increasingly, these effects are found to linger long after removal of the invader. We examined how soil chemistry, bacterial communities, and litter decomposition varied with cover of Euonymus fortunei, an invasive evergreen liana, in two central Kentucky deciduous forests. In one forest, E. fortunei invaded in the late 1990s but invasion remained patchy and we paired invaded and uninvaded plots to examine the associations between E. fortunei cover and our response variables. In the second forest, E. fortunei had completely invaded the forest by 2005; areas where it had been selectively removed by 2010 were paired with an adjacent invaded plot. Where E. fortunei had patchily invaded, E. fortunei patches had up to 3.5× nitrogen, 2.7× carbon, and 1.9× more labile glomalin in soils than uninvaded plots, whereas there were no differences in soil characteristics between invaded and removal plots. In the patchily invaded forest, bacterial community composition varied among invaded and non-invaded plots, whereas bacterial communities did not vary among invaded and removal plots. Finally, E. fortunei leaf litter decomposed faster (k = 4.91 year^?1) than the native liana (k = 3.77 year^?1), Vitis vulpina; decomposition of both E. fortunei and V. vulpina was faster in invaded (k = 7.10 year^?1) than removal plots (k = 4.77 year^?1). Our findings suggest that E. fortunei invasion increases the rate of leaf litter decomposition via high-quality litter, alters the decomposition environment, and shifts in the soil biotic communities associated with a dense mat of wintercreeper. Land managers with limited resources should target the densest mats for the greatest restoration potential and remove wintercreeper patches before they establish dense mats.     

Two new species of Eupatorium (Asteraceae) from northeastern Mexico

Two closely related new species ofEupatorium,E. tamaulipanum from southeastern Tamaulipas andE. xalapanum from central Veracruz, are described herein. The latter is diploid with 2n=20. Their relationship appears to be with the genusEupatoriastrum (subtribe Critoniinae, sensu Robinson and King), but an equally good case might be made for inclusion in the generaChromolaena, Bartlettina, orTamaulipa of subtribes Praxelinae, Hebecliniinae, and Gyptidinae respectively, as circumscribed by King and Robinson. While their splintered treatment ofEupatorium, and the Eupatorieae generally, often provides unequivocal “generic” placement of known or newly described species, many others appear to be rather arbitrarily placed, including some whose possible generic positions might include three or more of their subtribal groupings.     

Notes on the asteraceae of the Southeastern United States

Nomenclatural innovations are validated inAster, Chrysopsis, Eupatorium,Gaillardia, Helianthus, Prenanthes, Silphium, andSolidago. The genusChrysopsis is maintained as distinct fromHeterotheca, andHelianthus smithii Heiser is reduced to synonymy underH. microcephalus Torr. & Gray.     

Revegetation of steep rocky slopes: Planting climbing vegetation species in artificially drilled holes

A method of vegetation establishment with rocky slopes was conducted by planting three climbing plant species (Parthenocissus tricuspidata (Sieb.et Zucc) Planch, Hedera helix and Euonymus fortunei (f. minimus)) an artificial hole drilled on a rocky slope surface of an abandoned quarry. During the experiment period for 18 months, plant growth and dynamics of soil moisture content in holes were surveyed. The results indicated that artificial holes may save soil on the rocky slope for plant growth, but water deficit was the key limiting factor to plant growth in the hot summer. P. tricuspidata and E. fortunei had higher survival and growth rates than H. helix. They showed good adaptability to the disadvantageous growing conditions of rocky slope. The experiment demonstrated that P. tricuspidata and E. fortunei could be used as pioneer plant species for revegetation of rocky slopes.     

桐-药复合经营模式下泡桐丛枝菌根真菌群落结构特征

采用Illumina MiSeq高通量测序技术,研究江西鄱阳湖周边平原岗地的泡桐纯林及桐-药复合经营模式(泡桐-玉竹、泡桐-麦冬和泡桐-射干)下泡桐丛枝菌根真菌(arbuscular mycorrhizae fungi, AMF)群落结构特征。研究发现,泡桐AMF群落主要由球囊霉科、巨孢囊霉科、无梗囊霉科和多孢囊霉科组成,其中球囊霉科真菌占绝对优势,但不同科的相对丰度在不同经营模式下仍存在差异。与泡桐纯林相比,桐-药复合经营模式会降低泡桐菌根侵染率及AMF群落多样性。只有泡桐-射干经营模式中的泡桐含有多孢囊霉科真菌,且相对多度占2.73%。研究结果表明桐-药复合经营模式下中药材种类的差异会不同程度地改变泡桐AMF的群落结构。这为进一步研究桐-药复合经营模式下泡桐AMF的生态功能和资源利用提供了科学依据。     

Osteogenic effects of flavonoid aglycones from an osteoprotective fraction of Drynaria fortunei—An in vitro efficacy study

Drynaria fortunei (Kunze) J. Sm. is a traditional Chinese herb used for the treatment of osteoporosis and other bone metabolic disorders. Previous studies demonstrated that “small polar active fraction in Drynaria fortunei (SDF)”exerted osteoprotective effects in ovariectomized (OVX) mice. This study aims to investigate the constituents in SDF and systemically evaluate their osteogenic effects in vitro. Five flavonoid aglycones, naringenin, kurarinone, kushennol F, xanthogalenol, and sophoraflavanone G were identified in SDF. All the compounds did not show effects on proliferation of osteoblastic UMR 106 cells at the concentrations of 0.1-1000 nM, but significantly increased the ALP activity of the cells at most of the concentrations from 10 nm to 1000 nM. Xanthogalenol at the concentration of 100 nM significantly increased concentration of acid-solubilized calcium. ICI 182,780, antagonist of estrogen receptor (ER), diminished the effect of kushennol F on ALP activity and the effect of xanthogalenol on acid-solubilized calcium. In conclusion, flavonoid aglycones in SDF could promote differentiation and mineralization of osteoblastic UMR 106 cells in vitro, which was explained by activation of ER signaling pathway. This study provides scientific evidences for the conduction of in vivo experiments to confirm potential effects of flavonoid aglycones on preventing OVX-induced osteoporosis.     

A new species of Brickellia,subgenus Phanerostylis (Asteraceae)

Brickellia nesomii, a new species from northeastern Mexico, is described. It belongs to the subgenus Phanerostylis, which Gray originally placed in Eupatorium; King and Robinson elevated the taxon to generic rank; it is herein kept at the subgeneric level but transferred to Brickellia. Reasons for this transfer are given. Barroetea glutinosa, positioned by King and Robinson in Phanerostylis, is excluded.     

Effect of leaf age on epicuticular wax alkanes in Rhododendron

Alkane distribution pattern in epicuticular wax of Rhododendron fortunei cv Admiral Piet Hein leaves remains unchanged from the age of 6 weeks to abscission.     

High connectivity and migration potentiate the invasion of Limnoperna fortunei (Mollusca: Mytilidae) in South America

Even after almost 30 years of Limnoperna fortunei introduction into South America, it is still unclear how the source and propagules are connected. Here, we present genetic evidence of population connectivity and gene flow of L. fortunei propagules from Asia into South America, proposing the main invasion routes into South America. To achieve that we expanded the sampling effort to cover all occurrence points of L. fortunei in South America. We sequenced the mtDNA COI gene and genotyped eight microsatellite loci (ML), and we evaluated the genetic source of the recently introduced population in Sobradinho hydroelectric power plant reservoir in Northeast Brazil. Our results revealed that China is the main genetic source of propagules for the Sobradinho population. We also found COI haplotypes and ML genotypes unique to South American populations, demonstrating a bridgehead effect likely caused by local mutation, adaptation, and admixture patterns that are maintained by high levels of gene flow among them. However, two genetic barriers were also detected. We concluded that L. fortunei is a well-established invader and is still rapidly expanding in Brazil, and the Amazon hydrographic basin is under an alarming threat of invasion.