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Viscum album L., (Common Mistletoe), is a hemiparasitic shrub that lives on a wide range of woody plant species, known since Neolithic period for its ritual and for pharmacological properties. Up to now, no investigation has been reported on the chemical composition of the essential oils of V. album aerial parts in relation with the diverse host trees. Consequently, the essential oils compositions of three Sicilian accession of V. album, growing on Quercus suber L., Crataegus monogyna Jacq. and Olea europaea L. var. europaea cv. 'Santagatese', respectively, were evaluated by GC-MS. The three populations showed quite different profiles indicating that the nature of the host considerably influences the chemical composition of the guest plant, V. album. [ABSTRACT FROM AUTHOR]

Dendrophthora kuijtiana (Santalaceae), a new species of mistletoe endemic to the páramos and subpáramos of the Venezuelan Andes, is described and illustrated. We discuss aspects of its ecology, and taxonomic affinities with Dendrophthora davidsei. In addition, we report a new record (D. paucifolia) and two updates (D. karuaiana y D. warmingii) to Dendrophthora in Venezuela and present a dichotomous key to identify the species of Dendrophthora reported for the Guaramacal National Park. [ABSTRACT FROM AUTHOR]

Most species of Santalales (the sandalwood order) are hemiparasites, including both facultative and obligate hemiparasites. Despite its rich diversity, only a small fraction of the species in the sandalwood order have sequenced plastomes. The evolution of parasitism–associated plastome reduction in Santalales remains under-studied. Here, we report the complete plastomes of three facultative hemiparasites (Pyrularia edulis , Cervantesiaceae; Osyris wightiana , and Santalum album , Santalaceae), and two obligate hemiparasites (Viscum liquidambaricolum and Viscum ovalifolium , Viscaceae). Coupled with publicly available data, we investigated the dynamics of plastome degradation in Santalales hemiparasites. Our results indicate that these hemiparasites can be characterized by various degrees of plastome downsizing, structural rearrangement, and gene loss. The loss or pseudogenization of ndh genes was commonly observed in Santalales hemiparasites, which may be correlated to the lifestyle shift from photoautotroph to hemiparasitism. However, the obligate hemiparasites did not exhibit a consistently higher level of gene loss or pseudogenization compared to facultative hemiparasites, which suggests that the degree of plastome reduction is not correlated with the trophic level facultative or obligate hemiparasitism. Instead, closely related taxa tend to possess highly similar plastome size, structure, and gene content. This implies the parasitism-associated plastome degradation in Santalales may evolve in a lineage-specific manner. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the in vitro ovicidal activity of an ethyl acetate extract from Arceuthobium vaginatum (EtOAc-E) and their subfractions (AvR5-AvR14) against Haemonchus contortus using the egg hatching inhibition (EHI) test. The EtOAc-E and subfractions were tested at 0.12-2.00 and at 0.015-2.0 mg/mL, respectively. Distilled water and methanol (2%) were used as negative controls and Thiabendazole (0.10 mg/mL) as a positive control. Treatments with a dependent effect on concentration were subjected to regression analysis to determine the effective concentrations (EC50 and EC90). The major secondary compounds present in the extract and subfractions were identified by high performance liquid chromatography (HPLC). The EtOAc-E and AvR9 exhibited the best ovicidal effect recording 97.5 and 100% of EHI at 0.25 mg/mL, respectively. The EtOAc-E and AvR9 displayed an EC50= 0.12 and 0.08 mg/mL, respectively. The HPLC analysis in the EtOAc-E and bioactive fractions indicated the presence of a polyphenol, glycosylated flavanones, quercetin glucoside, cinnamates, coumarin, cinnamic acid derivative, ferulic acid, coumarate, naringenin, protocatechuic acid and naringin. Results demonstrated that A. vaginatum extract and fraction is able to inhibit the egg hatch process of H. contortus and could be a viable option for the control of small ruminant haemonchosis.

The type of Dendrophthora bonaniae is clarified, and lectotypes for Dendrophthora domingensis, D. ekmanii (a synonym of D. domingensis), D. glauca, D. nipensis (a synonym of D. glauca), D. oocarpa (a synonym of D. domingensis), and D. purpurascens are designated. In addition, a new taxonomic status for D. glauca subsp. purpurascens is proposed. [ABSTRACT FROM AUTHOR]

Premise of the Study: The sandalwood order (Santalales) includes members that present a diverse array of inflorescence types, some of which are unique among angiosperms. This diversity presents not only interpretational challenges but also opportunities to test fundamental concepts in plant morphology. Here we used modern phylogenetic approaches to address the evolution of inflorescences in the sandalwood order. Methods: Phylogenetic analyses of two nuclear and three chloroplast genes were conducted on representatives of 146 of the 163 genera in the order. A matrix was constructed that scored nine characters dealing with inflorescences. One character, "trios", that encompasses any grouping of three flowers (i.e., both dichasia and triads) was optimized on samples of the posterior distribution of trees from the Bayesian analysis using BayesTraits. Three nodes were examined: the most recent common ancestors of (A) all ingroup members, (B) Loranthaceae, and (C) Opiliaceae, Santalaceae s.l., and Viscaceae. Key Results: The phylogenetic analysis resulted in many fully resolved nodes across Santalales with strong support for 18 clades previously named as families. The trios character was not supported for nodes A and C, whereas it was supported for node B where this partial inflorescence type is best described as a triad. Conclusions: Essentially every major inflorescence type can be found in Santalales; however, the dichasium, a type of partial inflorescence, is rarely seen and is not plesiomorphic for the order. In the family Erythropalaceae, inflorescences are mostly in small, axillary fascicles or cymes. Successive families show both cymose and racemose types and compound systems (e.g., thyrses). Inflorescences in Amphorogynaceae and Viscaceae are not dichasial and in general are difficult to compare to "standard" inflorescences. [ABSTRACT FROM AUTHOR]

The morphological variability of two biostratigraphically important diatom species of the Russian Far East, Alveolophora areolata (Moisseeva) Moisseeva and Alveolophora bifaria Nevretdinova et Moisseeva,was studied using light and scanning electron microscopy. High variability was found in mantle height, diameter, stria organization, areola location on the valve face, alveolus structure and costae of A. bifaria, but less variability in A. areolata. Separation valves of A. areolata lack spines, and rimoportulae were found on the valve face for the first time. Based on the new morphological data, descriptions for these taxa have been emended. [ABSTRACT FROM AUTHOR]

Abstract: Aggregated distributions of parasite individuals across host individuals are nearly ubiquitous among parasitic taxa. The size and sex ratio of the population of one parasite species infecting a single host (hereafter “infrapopulation”) can influence parasite fitness through intraspecific competition, mate availability and the ability to attract vectors for transmission of parasite propagules. Competition for resources and for pollen and seed vector services may limit reproductive success (pollen receipt, fruit production and seed dispersal) in large infrapopulations of parasitic plants, while mate limitation or reduced ability to attract vectors may limit this success in small infrapopulations. Using a dioecious parasitic plant, desert mistletoe Phoradendron californicum, we experimentally removed reproductive tissue from male parasites in whole infrapopulations to test for independent effects of infrapopulation size and within‐host mate availability on female fitness. As desert mistletoe requires both pollen and seed vectors for successful reproduction, the species provides the opportunity to test how infrapopulation characteristics affect multiple components of parasite fitness. We found that insect‐mediated pollen receipt decreased for parasites on treated hosts, consistent with within‐host mate limitation. Additionally, the relationship between mate availability and fruit production per flower ranged from neutral to positive depending on year of the experiment. As expected if competition for host resources limits reproductive success more than mate availability in larger infrapopulations, the greater pollen receipt to females in large infrapopulations did not generally translate into increased mistletoe fruit production. Relationships between mistletoe fruit production per flower and infrapopulation size ranged from negative to neutral. Both pollen receipt and pollinator visitation increased with infrapopulation size, indicating that larger populations can be more attractive to pollen vectors independent of mate availability. However, we found no relationship between infrapopulation size and fruit removal by dispersers and, thus, no evidence that attraction of seed dispersal vectors increases with infrapopulation size. Synthesis. These results highlight the interactive roles of within‐host processes (resource competition, mate availability and vector attraction) in determining the fitness of biotically transmitted parasite individuals. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Arceuthobium spp. (non-EU), a well-defined and distinguishable group of parasitic plant species of the family Viscaceae, also known as dwarf mistletoes. These are flowering plants parasitising a wide range of conifers of the families Pinaceae and Cupressaceae. Arceuthobium species (non-EU) are regulated in Council Directive 2000/29/EC (Annex IAI) as harmful organisms whose introduction into the EU is banned. Many Arceuthobium species are recognised, with most dwarf mistletoes native in the New World, and north-western Mexico and the western USA as the centre of diversity for the genus. Only two Arceuthobium species are native (and reported to be present) in the EU (Arceuthobium azoricum and Arceuthobium oxycedrum), which are thus not part of this pest categorisation. Hosts of non-EU dwarf mistletoes include species of the genera Abies, Cupressus, Juniperus, Larix, Picea, Pinus, Pseudotsuga and Tsuga. Most Arceuthobium spp. can parasitise more than one species of conifer host. Dwarf mistletoes could enter the EU via host plants for planting and cut branches, but these pathways are closed. They could establish in the EU, as hosts are widespread and climatic conditions are favourable. They would be able to spread following establishment by human movement of host plants for planting and cut branches, as well as natural spread. Should non-EU dwarf mistletoes be introduced in the EU, impacts can be expected on coniferous woodlands, plantations, ornamental trees and nurseries. The main uncertainties concern (i) the precise distribution and host range of the individual Arceuthobium spp. and (ii) the level of susceptibility of conifers native to Europe. For Arceuthobium spp. (non-EU) as a group of organisms, the criteria assessed by the Panel for consideration as a potential quarantine pest are met, while, for regulated non-quarantine pests, the criterion on the pest presence in the EU is not met. [ABSTRACT FROM AUTHOR]

The distribution of parasitic plants is governed by the availability and distribution of suitable host species. Here we report the distributions, host associations and genetic variability of the three endemic New Zealand species of Korthalsella (Viscaceae) mistletoes. These species differ in their primary host and in the breadth of secondary and tertiary hosts. Korthalsella salicornioides is the most host-specific, with 96% of the total records from the primary (Leptospermum scoparium s.l. [Myrtaceae]) and secondary (Kunzea robusta [Myrtaceae]) hosts, but 26 host taxa (six genera in five families) recorded overall. Korthalsella clavata and K. lindsayi are more generalist species, parasitising 44 taxa (19 genera in 14 families) and 42 taxa (13 genera in 11 families), respectively. For K. clavata, Coprosma propinqua (Rubiaceae) and C. dumosa are the primary and secondary hosts, respectively, representing 66% of the total records. For K. lindsayi, Melicope simplex (Rutaceae) is the primary host (26% of records), whereas Coprosma crassifolia, Lophomyrtus obcordata (Myrtaceae), Myrsine australis (Primulaceae) and M. divaricata are secondary hosts. The only overlap among hosts is at the tertiary level, with K. clavata and K. lindsayi sharing Coprosma rigida and C. virescens, and among hosts that are rarely parasitised. Korthalsella salicornioides is the most widely distributed species occurring widely on the North and South Islands, while K. clavata is rare in the North Island and K. lindsayi is rare in the western regions of the South Island. Comparative sequencing of nuclear internal transcribed spacers and plastid trnQ-rps16 for the three mistletoes revealed that within-species genetic structure is geographic rather than host-based. Additionally, some plastid haplotypes and ITS sequence types shared between K. clavata and K. lindsayi may result from local hybridisation and introgression between the two species in a few locations. [ABSTRACT FROM AUTHOR]

There have been four subspecies of hemlock dwarf mistletoe (Arceuthobium tsugense: Viscaceae) described by various investigators of this complex group of parasitic flowering plants: subsp. tsugense, subsp. amabilae, subsp. contortae, and subsp. mertensianae. As suggested by their subspecific epithets, these taxa differ in their host affinities; parasitizing different and the same hosts to varying degrees. Although these taxa also have morphological differences, their classification has been under debate for many years. Therefore, we compared the morphological characteristics of each subspecies using both univariate and multivariate statistical analyses in order to better assess their differences. Because some investigators have grouped hemlock dwarf mistletoe with western dwarf mistletoe (A. campylopodum), we also compared the subspecies of hemlock dwarf mistletoe with western dwarf mistletoe. Our morphometric analyses demonstrated that all of the subspecies are morphologically distinct from western dwarf mistletoe and that subsp. contortae is the most morphologically differentiated of the subspecies. Overlap in the morphological characters across two of the other three subspecies was evident; yet, subsp. amabilae and subsp. mertensianae were also consistently delimited using female and male plant morphologies. Statistical comparisons of female or male plants via standard and stepwise discriminant function analyses demonstrated that without consideration of host plant, female and male A. tsugense subsp. tsugense are morphologically similar to corresponding plants of subsp. amabilae and mertensianae but not subsp. contortae or A. campylopodum. [ABSTRACT FROM AUTHOR]

PREMISE OF THE STUDY:: Extant dwarf mistletoes (Arceuthobium M. Bieb., Viscaceae) are hemiparasites with complex roles in nature. They are one of the most severe pests in northern hemisphere conifer forests, but they also enhance the structural complexity and species diversity of the forests. Here, we describe the first pre‐Miocene macrofossils of dwarf mistletoes. The fossils from Eocene Baltic amber provide new insights into the morphological evolution of the Arceuthobium lineage and its paleobiogeography. METHODS:: The amber inclusions were investigated with light microscopy and compared with extant Viscaceae and to historic descriptions of lost Baltic amber fossils with affinities to Viscaceae. KEY RESULTS:: Six fossil species of the Arceuthobium lineage, A. johnianum comb. nov., A. mengeanum comb. nov., A. conwentzii sp. nov., A. groehnii sp. nov., A. viscoides comb. nov. and A. obovatum sp. nov., occurred in source forests of Baltic amber, representing the oldest macrofossil evidence of dwarf mistletoes. They share morphological features of their bracts, internodes, fruits, and stomata with extant Arceuthobium. Differences from extant dwarf mistletoes, such as the perianth merosity, the nonfusion of squamate bracts and presence of oblanceolate expanded leaves, indicate their affiliation to an ancient lineage of the genus. CONCLUSIONS:: The occurrence of six species of dwarf mistletoes in a single amber deposit suggests Arceuthobium was a keystone taxon of the Baltic amber source area. As in extant conifer forests, they probably influenced the structural complexity of the forest, not only leading to more open woodlands but also increasing species diversity, at least at a microhabitat scale. [ABSTRACT FROM AUTHOR]

This work presents descriptions, morphological and ecological comments on the species of Santalaceae recorded for the cangas of Serra dos Carajás in the Pará state. Were recorded two genera and eight species: Dendrophthora warmingii, Phoradendron crassifolium, P. dipterum, P. mucronatum, P. obtusissimum, P. piperoides, P. quadrangulare, widely distributed in Central and South America, and P. tunaeforme only registered in Venezuela and Brazil. [ABSTRACT FROM AUTHOR]

The utility of the trnL-F region of the chloroplast DNA for inferring relationships in 26 taxa in the mistletoe tribe Phoradendreae (Viscaceae) was compared with that of sequences from three regions of the nuclear ribosomal DNA (nrDNA). Chloroplast- and nuclear-inferred phylogenies generally were congruent based on maximum parsimony analysis of nucleotide substitution data. Results suggested that the intron and intergenic spacer of the chloroplast partition were not sufficiently variable to resolve phylogenetic relationships among either close relatives or more distantly related species. The distribution of insertions and deletions generally supported the phylogeny inferred from nucleotide substitution data. However, presence or absence of a 59-nucleotide inversion in the trnL-F intergenic spacer of eight Phoradendron species showed no agreement with the topology inferred from molecular and morphological data. Combined analyses of the nuclear partitions and the chloroplast region (with the homoplasious inversion inserted in reverse orientation) provided strong support for P. californicum as sister to a clade uniting North American species and not as sister to a clade comprising more tropical species. Consistent with results from previous studies using nrDNA, a lineage in the Phoradendron leucarpum complex (comprising subsp. leucarpum and macrophyllum) was strongly supported, but subspecies tomentosum was not confidently placed. [ABSTRACT FROM AUTHOR]

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PREMISE OF THE STUDY: Loranthaceae, Santalaceae, and Viscaceae are the most diversified hemiparasitic families of Santalales in the Andes. Their partial inflorescences (PIs) vary from solitary flowers, or dichasia in most Santalales, to congested floral groups along articles in most Viscaceae. The atypical articled inflorescences in Phoradendreae (Viscaceae), a phylogenetic novelty restricted to this tribe, have been variously described as racemes, spikes, fascicles, or as intercalary inflorescences, but no developmental studies have been performed to compare them with the construction of PIs across Santalales. M ETHODS: We used standard light microscopy and scanning electron microscopy to record the inflorescence development in members of Phoradendreae (Viscaceae) in comparison to those in species of Aetanthus, Gaiadendron, Oryctanthus, Passovia, and Peristethium (Loranthaceae) and Antidaphne (Santalaceae). KEY RESULTS: Morphological and developmental comparisons as well as optimization onto a phylogenetic framework indicate that individual inflorescences in Santalales are indeterminate and are formed by axillary cymose PIs. The latter correspond to dichasia, either simple, compound, or variously reduced by abortion of lateral flowers, abortion of the terminal flower, or loss of bracteoles. CONCLUSIONS: Dichasia are plesiomorphic in Santalales. These results favor the interpretation that inflorescences in Phoradendreae are formed by the fusion of serial dichasia (=floral rows) with the main inflorescence axis via syndesmy. We compared this interpretation with the competing one based on the co-occurrence of collateral and serial floral buds. [ABSTRACT FROM AUTHOR]

Phoradendron y Psittacanthus habitan exclusivamente en América y agrupan plantas hemiparásitas. El conocimiento de la anatomía de especies mexicanas es escaso y son varias en las que no ha sido tratada. Este trabajo describe la anatomía de 5 especies de los géneros que arriba se mencionan a partir de cortes con micrótomo, a mano libre, macerados y diafanizados. Se hicieron pruebas histoquímicas en material fresco. Entre las especies existen caracteres comunes. La arquitectura foliar se describe como venación actinódroma reticulada y venas laterales con las vénulas modificadas en traqueidas dilatadas. Anatómicamente, la hoja mostró estomas paracíticos y mesofilo isobilateral. Las drusas son abundantes en pecíolo y lámina de Phoradendron. El tallo presenta los vasos del xilema en hileras radiales, el parénquima cortical y la médula contienen drusas y braquiesclereidas. El polen es esférico o triangular y tricolporado. Psittacanthus se distingue porque debajo del ovario se desarrolla un tejido de células con paredes engrosadas y lignificadas y el fruto contiene una viscina conspicua. Los cristales prismáticos, la cutícula rugosa, la peridermis con tejido suberoso y los haces vasculares en el exocarpo, no se habían descrito anteriormente. Las astroesclereidas cristalíferas, el córtex heterogéneo, el epitelio cuticular y la cutícula estriada que citan otros autores, no se observaron. Las substancias pécticas y los compuestos fenólicos tienen mayor presencia en Psittacanthus.Phoradendron and Psittacanthus only grow in America and they include hemiparasitic plants. The anatomy of Mexican species is partial and some of them had not anatomically been studied. The vegetative and reproductive anatomy of 5 species was described as seen in slides obtained through microtome, by free hand, and macerated and clarified tissues. Histochemistry tests on fresh material were made. The leaves have paracytic stomata, reticulate actinodromous venation, lateral veins with terminal portions modified to dilated tracheids and isobilateral or homogenous mesophyll. Druses are abundant in petiole and lamina of Phoradendron. The stem has xylem vessels in radial raws and druses and brachysclereids are common in the cortical parenchyma and the pith. Pollen is spherical or triangular and tricolporate. In Psittacanthus, under ovary a tissue of cells with lignified and thickness walls is present. The viscid tissue of the fruit of Psittacanthus is bigger. Prismatic crystals, striated cuticle, suberous peridermis and vascular bundles in the exocarp had not previously been described in these species. Astrosclereids with prismatic crystals, a heterogeneous cortex, a cuticular epithelium and a striated cuticle described for other authors were not found. Pectic substances and phenolic compounds are most abundant in Psittacanthus.

The current study evaluated the antihyperglycemic and hypolipidaemic effects of methanolic extract of Viscum schimperi Engl. whole parts in streptozotocin (STZ)-induced diabetic rats. The antihyperglycemic activity was evaluated by measuring the fasting blood glucose level (BGL) and by applying the oral glucose tolerance test (OGTT) in diabetic rats. In addition, the effect of the extract on blood plasma insulin was measured as well as its effect on tissue glycogen contents in muscle and liver. The hypolipidaemic effect was evaluated by assaying triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C). Diabetic male Wistar rats of a same age group were treated orally once a day for 4 weeks with a dose of 500 mg/kg bw of methanolic extract. Fasting BGL was measured on the 7th, 14th, 21st and 28th days, while plasma insulin levels were measured at the end of the 28th day. Maximum reduction in BGL of 37% was observed at the 4th week. Furthermore, there was a significant increase in plasma insulin, by 321.6%. The hypolipidaemic effect was demonstrated by significant reductions in plasma TC (32.6%), in TG (32.2%) and in LDL-C (27.2%); and an increase in HDL-C of 171.5%. The present data suggest that V. schimperi has both antihyperglycemic and hypolipidaemic effects with high insulin-secreting activity.

Neste estudo, foi realizada a análise morfoanatômica e do padrão de venação das folhas de seis espécies de hemiparasitas (Phoradendron, Viscaceae) presentes em Maringá, Paraná. As folhas mostraram grande variação em relação ao formato do limbo e do ápice foliar. A nervação é do tipo trinérvea em P. obtusissimum, P. mucronatum e P. quadrangulare, quinquinérvea em P. linearifolium e P. perrottetii e quintuplinérvea em P. piperoides. A distribuição das nervuras em todas as espécies é do tipo acródromo, suprabasal em P. piperoides e basal nas demais espécies. Anatomicamente, as espécies apresentaram padrão semelhante de distribuição de tecidos: as folhas são anfiestomáticas, com estômatos paracíticos, recobertas por cutícula fina; as paredes periclinais externas das células epidérmicas são espessas e cutinizadas; o mesofilo é homogêneo, com braquiesclereídes e traqueídes dilatadas; idioblastos com cristais, compostos lipídicos e fenólicos também ocorrem nos estratos parenquimáticos. O pecíolo é recoberto por epiderme papilosa. Os feixes vasculares foliares são colaterais abertos, com fibras derivadas do floema e xilema primários. Os aspectos morfológicos são os mais indicados para a distinção de espécies de Phoradendron, juntamente com as análises do padrão de venação, sendo os aspectos anatômicos complementares.

Neste estudo, foi realizada a análise morfoanatômica do caule de seis espécies de hemiparasitas (Phoradendron, Viscaceae) ocorrentes no município de Maringá, Paraná. Dependendo da espécie, o caule apresenta em seção transversal formato circular, losangular com expansões nos vértices ou quadrangular. O caule apresenta-se recoberto por cutícula fina; as células epidérmicas formam papilas pouco ou bastante proeminentes, dependendo da espécie; possuem as paredes anticlinais e periclinais externas espessas e cutinizadas. Após crescimento secundário acentuado, esse revestimento cutinizado pode se romper, formando uma região de cicatrização; a presença de papilas auxilia no crescimento em diâmetro. O parênquima cortical é fotossintético, possui braquiesclereídes, idioblastos cristalíferos e secretores de compostos fenólicos, além de acumular substâncias lipídicas. Os feixes vasculares apresentam crescimento secundário já nos primeiros entrenós, formando, em seguida, um sistema vascular compacto, com raios portando grande quantidade de amiloplastos. Do floema e xilema primários derivam calotas de fibras. A medula, inicialmente parenquimática, torna-se esclerificada, portando cristais, amido e grandes grupos de braquiesclereídes. O formato do caule, em seção transversal, é a característica mais indicada para fins taxonômicos, sendo as características anatômicas complementares.

Marker based standardization of plant drugs has become important for obtaining their reproducible therapeutic effects. Viscum album L. (Ujjral; family - Viscaceae), an Indian traditional plant, has not been standardized on the basis of marker compound. Thus, it was considered worthwhile to isolate main chemical constituent from V. album aerial parts and to standardize plant on the basis of isolated constituent by a developed and validated TLC densitometric method. The ethyl acetate fraction (EAF) was obtained from methanol extract of plant using standard procedure. EAF of the plant was subjected to column chromatography and yielded orange-yellow coloured crystalline compound. The compound was characterized as 2',4-dihydroxy-4',6'-dimethoxy chalcone. A TLC densitometric method was developed to estimate the content of isolated chalcone compound. The content of 2',4-dihydroxy-4',6'-dimethoxy chalcone was found to be 0.0375% w/w. The developed TLC densitometric method was found to be precise and accurate as per ICH guidelines. [ABSTRACT FROM AUTHOR]

The morphology and morphogenesis of two stylonychid ciliates, Stylonychia ammermanni Gupta et al., 2001 and Tetmemena bifaria ( Stokes, 1887 ) Berger, 2001 , isolated from soil samples of Lombardia region, Northern Italy, and water samples from Cheonggancheon stream, South Korea, were investigated. The Italian population of S . ammermanni was found to be very similar in morphology to the Indian type population and the junior synonym S. harbinensis Shi and Ammermann, 2004 since most of the morphometric data overlapped. On the contrary, the Korean population of S. ammermanni showed some non-overlapping differences in ciliature suggesting a separation at subspecies level, i.e., S. ammermanni ammermanni and S. ammermanni koreana nov. subspec. Furthermore, the resting cyst of the Italian population of S. ammermanni has many ring-shaped structures on the surface which, however, were not observed in the Korean population. Phylogenetic analyses based on the SSU rRNA gene sequences show that the Italian and Korean populations of S. ammermanni fit well into the S. mytilus complex and moderately support the subspecies separation. Additionally, we split Tetmemena bifaria into two subspecies, viz., T. bifaria bifaria and T. bifaria minima nov. subspec. based on differences in the number of adoral membranelles and number of cirri in the marginal rows of the Italian and the Argentinian populations in comparison with the populations described by Wirnsberger et al. (1985) . [ABSTRACT FROM AUTHOR]

Desert mistletoe, Phoradendron califomicum (Viscaceae), is a dioecious parasitic plant that grows on woody legumes in the Mojave and Sonoran Deserts, produces minute flowers during winter, and is dispersed by birds defecating fruits. Pollination of desert mistletoe has not been examined despite the species' reliance on insects for transporting pollen from male to female plants. I investigated the pollination of P. califomicum parasitizing Acacia greggii (Fabaceae) shrubs at 3 sites at different elevations in the Mojave Desert of southern Nevada during February 2015. I examined pollen from male flowers, aspirated insects landing on female flowers, and counted pollen grains in insect pollen loads. Desert mistletoe's tricolpate pollen differed from a previous description by being oblate instead of subprolate in equatorial view. Female flowers were visited by 13 species of Diptera in 10 genera and 6 families and 3 species of Hymenoptera in 3 families. Almost all (98.5%) of the pollen carried by insects was from desert mistletoe. Five species of phytophagous fruit flies in Tephritidae were frequently found on flowers, comprising 53% of the insects collected, but carried low amounts of P. califomicum pollen. Two species of blow flies in Calliphoridae, both larval decomposers of animals, were also relatively abundant on flowers and carried moderate to high pollen loads. Flies in Syrphidae, 2 predators and 1 plant-decomposer, carried varying amounts of conspecific pollen. Conspecific pollen loads also varied on a species of native bee in Halictidae and on naturalized honey bees in Apidae. Desert mistletoe appears to be pollinated mostly by tephritids, due to their abundance on female flowers, and by calliphorids. Blow flies would be more likely than fruit flies to carry pollen between male and female plants on different host shrubs due to their larger size and stronger flight. Parasitic, dioecious P califomicum plants appear to rely on a web of mutualism between fruit-eating birds and flower-fertilizing insects. [ABSTRACT FROM AUTHOR]

Typification of Dendrophthora buxifolia, a species of mistletoe from Cuba, is addressed here. A lectotype and epitype are designated. Also, a lectotype for Dendrophthora buxifolia var. rotundata, considered as a synonym, is designated. [ABSTRACT FROM AUTHOR]

Despite the biological importance of mistletoes in forests and woodlands globally, mistletoe biomass is rarely quantified, particularly in tropical regions. Thus, we constructed allometric models to predict the biomass of three mistletoe species (Erianthemum ngamicum , Plicosepalus kalachariensis , and Viscum verrucosum) in semi-arid savanna, southwest Zimbabwe. We destructively sampled 30 individuals of each mistletoe species and recorded their broad haustorium diameter, narrow haustorium diameter, and the width, breadth, vertical depth, and percentage of leaves of the whole plant. After measuring the dry biomass of each mistletoe, we fitted linear regression models – selected and compared based on corrected Akaike Information Criterion (AICc) minimization. Mistletoe volume (r 2 = 0.95) best predicted biomass in E. ngamicum , while mistletoe size was the best predictor for P. kalachariensis (r 2 = 0.90) and V. verrucosum (r 2 = 0.95). Models using haustorium diameter had the lowest predictive power in all species. V. verrucosum and P. kalachariensis had greater total mean dry biomass than E. ngamicum. Stems constituted the larger proportion of total biomass than leaves in E. ngamicum (75 vs. 23%) but the reverse is true for P. kalachariensis (40 vs. 58%). Of the total biomass, fruits and flowers constituted 6% in V. verrucosum and E. ngamicum and 2% in P. kalachariensis. The leaf to stem biomass contribution decreases in E. ngamicum but increases in P. kalachariensis as the plant grows. Models using mistletoe biometry (width, breadth, and vertical depth of the whole plant), rather than host size (height, diameter at breast height, and canopy area), best predicted total mistletoe biomass. Not only does this enable estimation of mistletoe biomass beyond the scale of infected individuals, but the contribution of mistletoes to local biomass, carbon stock, and ecosystem processes (e.g., nutrient cycling) can also be quantified at different spatial scales helping elucidate their keystone role in semi-arid savanna. • Mistletoe load and biomass differ between mistletoe species. • Host size has positive but weak relationships with mistletoe load and biomass. • Host size is a poor predictor of mistletoe load and biomass. • Models including mistletoe width, breadth, and vertical depth better predict mistletoe biomass. • Biomass allocation to leaves and stems vary with mistletoe species, and the relevance of each changes as the plant grows. [ABSTRACT FROM AUTHOR]