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Research on the chloroplast genome of parasitic plants is limited. In particular, the homology between the chloroplast genomes of parasitic and hyperparasitic plants has not been reported yet. In this study, three chloroplast genomes of Taxillus (Taxillus chinensis, Taxillus delavayi, and Taxillus thibetensis) and one chloroplast genome of Phacellaria (Phacellaria rigidula) were sequenced and analyzed, among which T. chinensis is the host of P. rigidula. The chloroplast genomes of the four species were 119,941–138,492 bp in length. Compared with the chloroplast genome of the autotrophic plant Nicotiana tabacum, all of the ndh genes, three ribosomal protein genes, three tRNA genes and the infA gene were lost in the three Taxillus species. Meanwhile, in P. rigidula, the trnV-UAC gene and the ycf15 gene were lost, and only one ndh gene (ndhB) existed. The results of homology analysis showed that the homology between P. rigidula and its host T. chinensis was low, indicating that P. rigidula grows on its host T. chinensis but they do not share the chloroplast genome. In addition, horizontal gene transfer was not found between P. rigidula and its host T. chinensis. Several candidate highly variable regions in the chloroplast genomes of Taxillus and Phacellaria species were selected for species identification study. Phylogenetic analysis revealed that the species of Taxillus and Scurrula were closely related and supported that Scurrula and Taxillus should be treated as congeneric, while species in Phacellaria had a close relationship with that in Viscum.

The genus Tolypanthus and two species, Tolypanthus maclurei and Taxillus vestitus, are reported as new records for Vietnam. Taxonomy and geographical distribution of the newly recorded taxa are discussed; lectotypes of the genus Tolypanthus and the two species are designated. Detailed descriptions and illustrations of both newly recorded species as well as a key to species of Taxillus in Vietnam are provided. Diversity of the family Loranthaceae in Vietnam is briefly summarized.

Taxillus thibetensis (Lecomte) Danser (Loranthaceae), a species previously known only from China, is newly recorded from Vietnam. A specimen discovered in the rainforest of Lao Cai province, Northern Vietnam was identified as Taxillus thibetensis based on both morphological and molecular data. The Vietnamese individuals of Taxillus thibetensis are closely related to T. thibetensis in China. A detailed description, illustration and data on distribution, ecology, phenology of Vietnamese Taxillus thibetensis are provided

A new catechin derivative, catechin-5-O-(6-O-galloyl-β-glucopyranoside) (2), together with ten known flavonoids, was isolated from the leaves and stems of Taxillus theifer (Hayata) H. S. Kiu. T. theifer is a shrub parasitizing on different species of plants. Three samples of T. theifer on various host plants were collected and their chemical constituent variations were identified and estimated by HPLC/UV methods. A comparison of the constituents from T. theifer parasitizing on different host trees demonstrated that catechin (1), quercetin-3-O-(6-O-galloyl-β-glucopyranoside) (3), quercetin-3-O-β-glucopyranoside (5), and quercetin-3-O-β-glucuronide (6) were the major components in the title plant irrespective of the host tree. However, the content of some components varies for each sample.

Several molecular phylogenetic studies of the mistletoe family Loranthaceae have been published such that now the general pattern of relationships among the genera and their biogeographic histories are understood. Less is known about species relationships in the larger (> 10 species) genera. This study examines the taxonomically difficult genus Taxillus composed of 35–40 Asian species. The goal was to explore the genetic diversity present in Taxillus plastomes, locate genetically variable hotspots, and test these for their utility as potential DNA barcodes. Using genome skimming, complete plastomes, as well as nuclear and mitochondrial rDNA sequences, were newly generated for eight species. The plastome sequences were used in conjunction with seven publicly available Taxillus sequences and three sequences of Scurrula, a close generic relative. The Taxillus plastomes ranged from 121 to 123 kbp and encoded 90–93 plastid genes. In addition to all of the NADH dehydrogenase complex genes, four ribosomal genes, infA and four intron-containing tRNA genes were lost or pseudogenized in all of the Taxillus and Scurrula plastomes. The topologies of the plastome, mitochondrial rDNA and nuclear rDNA trees were generally congruent, though with discordance at the position of T. chinensis. Several variable regions in the plastomes were identified that have sufficient numbers of parsimony informative sites as to recover the major clades seen in the complete plastome tree. Instead of generating complete plastome sequences, our study showed that accD alone or the concatenation of accD and rbcL can be used in future studies to facilitate identification of Taxillus samples and to generate a molecular phylogeny with robust sampling within the genus.

Numerous variations are known to occur in the chloroplast genomes of parasitic plants. We determined the complete chloroplast genome sequences of two hemiparasitic species, Taxillus chinensis and T. sutchuenensis, using Illumina and PacBio sequencing technologies. These species are the first members of the family Loranthaceae to be sequenced. The complete chloroplast genomes of T. chinensis and T. sutchuenensis comprise circular 121,363 and 122,562 bp-long molecules with quadripartite structures, respectively. Compared with the chloroplast genomes of Nicotiana tabacum and Osyris alba, all ndh genes as well as three ribosomal protein genes, seven tRNA genes, four ycf genes, and the infA gene of these two species have been lost. The results of the maximum likelihood and neighbor-joining phylogenetic trees strongly support the theory that Loranthaceae and Viscaceae are monophyletic clades. This research reveals the effect of a parasitic lifestyle on the chloroplast structure and genome content of T. chinensis and T. sutchuenensis, and enhances our understanding of the discrepancies in terms of assembly results between Illumina and PacBio.

Taxillus yadoriki (Loranthaceae) is a hemiparasitic evergreen shrub distributed in Korea and Japan. We report the complete chloroplast genome of T. yadoriki to provide insight into the phylogenetic...

The present study investigates the potential of anti-urolithiatic activity of ethanolic extract of Taxillus tomentosus plant (EETT). Urolithiasis was induced by feeding the 0.75% of Ethylene glycol (EG) and 2% of Ammonium chloride (AC) in drinking water along with the normal feed in male wistar rats and then the anti-urolithiatic activity of EETT was evaluated. Acute toxicity study was conducted by LD 50 cutoff dose of 2000mg/kg body weight (BW), indicates that the drug to be much safer and 1/10 th (200mg/kg BW) and 1/5 th (400mg/kg BW) of LD 50 doses were selected for study. Serum and urine samples were analyzed for knowing the concentration of creatinine, calcium, urea, uric acid, oxalates and during the entire study, urolithiatic animals showed significantly high concentrations than normal animals. The EETT (200mg/kg BW and 400mg/kg BW) was showed good response to antiurolithiatic activity when compared to the standard drug cystone (CST). Keywords: a nti-urolithiatic activity, taxillus tomentosus, ethylene glyco, ammonium chloride, cystone.

Taxillus vestitus (Wallich) Danser (Loranthaceae) is a stem hemiparasite occurring in southwest China and Himalayas. In this study, we report the first complete plastome of this species. The plasto...

In general, studies of aerial parasitic plants known collectively as mistletoe have been carried out to inves-tigate their ecological and agricultural characteristics. However, with the recently increased level of interest in medicinalresources, research on different types of Korean mistletoe has also increased. This study was carried out to review the workon the taxonomy and ecology of Korean mistletoe in preparation for the industrial use of these plants in the future. Mis-tletoe types are flowering plants belonging to Santalales, which exist in the form of parasites on the branches of trees orshrubs. In Korea, five taxa of four genera in two families of mistletoe exist: Viscum coloratum (Komarov) Nakai f. col-oratum, Viscum coloratum (Komarov) Nakai f. rubroaurantiacum (Makino) Kitagawa and Korthalsella japonica (Thunb.)Engl. in Santalaceae, along with Loranthus tanakae Franch. et Sav. and Taxillus yadoriki (Sieb. ex Maxim.) Danser inLoranthaceae. As taxonomic studies of these species remain insufficient and given that the distribution ranges of these spe-cies are very wide, further observations pertaining to the morphological variations in each species are necessary. The dis-tribution of mistletoes is known to be determined by the host specificity, the interval between the hosts, the environmentalcondition, the habits of the host plant, the eating characteristics of mediators in the area, and their habitat selection features.

A new 8.O.6'-neolignan, threo-(7R, 8R)-7-acetoxy-3',4'-dimethoxy-3,4-dimethoxy-Δ-(8')-8.O.6'-neolignan (1) along with two known lignans (2) and (3), was isolated from the leaves and stems of Taxillus theifer. Structural elucidation was carried out by 1-D and 2-D-NMR spectroscopic methods, and the absolute configurations of C-7 and C-8 in 1 were determined on the basis of circular dichroism. Compound 2 is threo-7-acetoxy-3'-methoxy-3,4-dimethoxy-Δ-(7')-8.O.4'-neolignan obtained from a natural source for the first time, previously derived from a synthesis study of 8,4'-oxyneolignans.

A survey was conducted to identify the parasitic plant species occurring in timber and fruit trees during November 2015 to April 2017, in 15 Districts of Wet and Intermediate Zones of Sri Lanka using two stage stratified random sampling scheme. The parasitic plants on fruit and timber trees were identified by comparing them with the specimen in National Herbarium, Peradeniya. Host plant species were taxonomically identified after consultation of botanical experts and using species identification keys. Correlation between parameters were made using SAS software. Mistletoes infested in varying degrees in 27 perennial fruit and 20 timber tree species in different cropping systems. Dendrophthoe falcata, D. neilgherrensis, Scurrulla cordifolia, Viscum articulatum, Taxillus incanus, and V. orientale were the mistletoes species infested in fruit trees; whereas, D. falcata, D. neilgherrensis, S. cordifolia, S. parasitica, V. articulatum and V. orientale were found in timber species. D. falcata was the most predominent parasitic plant in both fruit and timber trees. Mangifera indica and Albizia odoratissima were the most susceptible host fruit and timber species, respectively. The study indicated that further studies are required on the increased occurrence of parasitic plants, their effects on host plants and development of control measures.

A number of desmid samples collected in Lapland appeared to be remarkably rich in zygospores. The spore morphology of Euastrum sinuosum Lenorm. ex Arch., Cosmarium tumidum Lund., C. isthmochondrum Nordst., Staurastrum dilatatum Ehr. ex Ralfs, Actinotaenium wollei (W. & G. S. West) Teil. ex Růž. & Pouz. and A. didymocarpum (Lund.) comb, nov., either when hitherto unknown or requiring a critical discussion is extensively treated. A new species, Cosmarium taxillus (with zygospores) is described. Repeatedly recorded incidences of a disturbed zygospore development and the grey to black pigmentation of the mesosporium are discussed in connection with the possible effect of habitat factors.

Morphogenetic studies were conducted in vitro on the embryo of the stem parasites, Dendrophthoe jalcata, Taxillus cuneatus, and T vestitus, and a root parasite, Nuytsia floribunda (Loranthaceae) The responses of young and mature embryos of Dendrophthoe were strikingly dissimilar For studying organogenesis, callus from different parts of the embryo was raised and maintained on modified WM containing IBA, KN, and CH When IBA was replaced by IAA, shoot buds developed from the callus The responses of the mature embryos of Dendrophthoe and Taxillus spp were similar; the formation of shoot buds and haustoria could be controlled The response of the mature embryo of Nuytsia was different; the cotyledons callused and later differentiated embryoids, roots, and shoots The potentiality for root and shoot formation was gradually lost on a particular medium, but the capacity for the differentiation of embryoids did not decline

Haustorial structure and behaviour are described for three South African species: Loranthus elegans ( Moquinia rubra ), L .( Tapinanthus ) prunifolius and L . ( Taxillus ) glaucus . Fundamental differences are revealed between them, although they are nearly related. In Moquinia rubra the haustorium extends against the wood and maintains contact by a meristematic surface layer with large parts of the host cambium, which continues to function, but forms only phloem where in contact with the haustorial meristem. In Tapinanthus prunifolius the haustorium spreads against the wrood, but interrupts the cambium and links up with the phloem ; numerous xylem connexions are established between radial surfaces of host wood and parasite. In both these species variations are described, attributable to relative age and vigour of host and parasite, or, in Moquinia rubra , to a different host. In Taxillus glaucus the haustorium does not penetrate to the cambium but spreads and branches in the outer tissues below the periderm, and then sends m any fine sinkers radially to the wood, where they become embedded like coarse medullary rays, including xylem elements. This aberrant form is closely matched by an unrelated American species, Psittacanthus sternbergianus , described by Solms-Laubach. Reference is made to still another type of attachment, the ‘wood-rose’ type, already described for a South African species, L . ( Erianthemum ) dregei , and a similar specimen is illustrated.

The chemical constituents of Japanese mistletoes, Taxillus yadoriki DANSER, Taxillus kaempferi DANSER, and Korthalsella japonica ENGLER, epiphyting to different host trees were compared, and the antimicrobial and hypotensive properties of some isolated flavonoids were examined. Two known flavonoid glycosides, hyperin and quercitrin, were isolated from Taxillus yadoriki DANSER, together with fatty acids, phytosterol, and phytosterol-glucoside. There was remarkable variation of contents of quercitrin among the plants on different host trees. From Taxillus kaempferi DANSER, fatty acids, phytosterol, phytosterol-glucoside, quercetin, avicularin, and taxillusin were isolated, and quercitrin and hyperin were also identified. These was no remarkable variation of compositions of flavonoid glycosides among the plants on different host trees. A known flavone glycoside, chrysoeriol-4'-O-glucoside, was isolated from Korthalsella japonica ENGLER, together with fatty acids, phytosterol, oleanolic acid, and phytosterol-glucoside. Chrysoeriol-4'-O-glucoside is contained in this plant irrespective of the host trees.