Euphorbia gokakensis sp. nov. (Euphorbiaceae) from sandstone formations in Karnataka,India

Euphorbia gokakensis, a new succulent species of Euphorbiaceae, is described from the Belgaum district of Karnataka, India. The new species belongs to Euphorbia subgen. Euphorbia, and closely resembles Euphorbia caducifolia Haines. However, it is distinguished by its characteristic dwarf habit forming a compact cushion that hardly exceeds 50 cm in height.     

Plant teratologies as a result of phytoplasma infections

The direct correlation between teratological cases and phytoplasma infections was ascertained in spontaneous and cultivated plant species. Plants, belonging to 31 species and 12 families, showing symptoms of growth abnormalities were collected and analysed. Attempted detection of Rhodococcus fascians by isolation, PCR indexing and 16S rRNA sequencing from fasciated tissues allowed to exclude its presence. Nested PCR by universal primers and 16S rRNA sequence analyses indicated the presence of phytoplasmas, belonging to six groups, in the 44% of symptomatic samples. Among the infected species, Austrocylindropuntia exaltata, Opuntia subulata, Euphorbia characias, Euphorbia dendroides, Euphorbia linifolia, Euphorbia myrsinites, Rumex buchephalophorus, Linaria multicaulis and Fedia cornucopiae represent new phytoplasma hosts world-wide. Moreover this is the first report of phytoplasma belonging to subgroup 16SrRNA II-I in Italy. These findings together with the known erratic distribution in plant tissues of these phloem-restricted prokaryotes indicate a close correlation between fasciation and similar growth disorders and phytoplasma infections.     

A new species and molecular phylogeny of Brazilian succulent Euphorbia sect. Brasilienses

A new species of Euphorbia sect. Brasilienses V.W. Steinm. & Dorsey is described. Euphorbia tetrangularis Hurbath & Cordeiro is endemic to the Serra de Montevidéu, a part of the Espinhaço Range located in the state of Minas Gerais, Brazil. It differs from other species within the section based on the following characters: 4-ribbed branches, green cyathia, and green cyathial glands with erect appendages. This new species would qualify as critically endangered (CR) according to IUCN criteria. An inferred phylogeny based on a combined dataset of nuclear (ITS1) and plastid regions (psbA-trnH, trnC-ycf6, matK, atpI-atpH, psbJ-petA, trnQ-rps16?×?1) confirms the monophyly of Euphorbia sect. Brasilienses and supports the recognition of E. tetrangularis. The phylogeny also suggests that this group probably underwent a recent radiation.     

New species of oidiopsis from Aurangabad maharashtra (India)

Summary This paper deals with two new species ofOidiopsis, O. convolvuli andO. euphorbiae, on two new hostsConvolvulus arvensis L. andEuphorbia microphylla Heyne. It also makes two new reports of its imperfect stage onTagetes erecta L. andAbutilon indicum L.     

Ultrastruktur und Entwicklungsgeschichte des Pollenkitts vonEuphorbia cyparissias,E. palustris undMercurialis perennis (Euphorbiaceae)

Development, fine structure and distribution of pollenkitt is investigated inEuphorbia cyparissias, E. palustris, andMercurialis perennis. The predominantly anemophilousM. perennis produces a great amount of strictly homogeneous pollenkitt, which is deposited in the exine caves. In contrast to this and to all other angiosperms so far investigated, bothEuphorbia species produce large quantities of an extremely inhomogeneous and particular pollenkitt. Its ultrastructure is quite different, both during its development and after its deposition on the exine surface: Lipid particles with different electron density and size are wrapped in a strictly homogeneous electron transparent matrix. This can be considered as new and additional proof for the secondary entomophily ofEuphorbia.

     

New records of fungal pathogens of euphorbia inarticulata from Aseer region,south-west Saudi Arabia: Neue aufzeichnungen über fungale pathogene von euphorbia inarticulata aus der Aseer-region im südwesten Saudi Arabiens

A 12 month period survey of the fungi associated with Euphorbia inarticulata was evaluated. Sampling was concentrated mainly in Aseer region (South-West Saudi Arabia) and seven fungal species were identified as pathogens of this plant. Melampsora euphorbiae and Alternaria euphorbiicola were the most common species on this plant. Bipolaris euphorbiae, Botrytis ricini, Colletotrichum gloeosporioides, Oidium sp., Sphaceloma poinsettiase and Uromyces euphorbiae were less frequent species. These fungal pathogens were recorded for the first time on Euphorbia inarticulata in Saudi Arabia. Scanning and transmission electron microscopy revealed the colonization of M. euphorbiae, as an example, in leaf tissues of E. inarticulata. Remarkable ultrastructural changes in chloroplasts and nuclei of infected cells of E. inarticulata as a result of infection by M. euphorbiae were observed.     

The ever increasing diversity of begomoviruses infecting non‐cultivated hosts: new species from Sida spp. and Leonurus sibiricus,plus two New World alphasatellites

Begomoviruses (whitefly‐transmitted, single‐stranded DNA plant viruses) are among the most damaging pathogens causing epidemics in economically important crops worldwide. Besides cultivated plants, many weed and wild hosts act as virus reservoirs where recombination may occur, resulting in new species. The aim of this study was to further characterise the diversity of begomoviruses infecting two major weed genera, Sida and Leonurus. Total DNA was extracted from samples collected in the states of Rio Grande do Sul, Paraná and Mato Grosso do Sul during the years 2009–2011. Viral genomes were enriched by rolling circle amplification (RCA), linearised into unit length genomes using various restriction enzymes, cloned and sequenced. A total of 78 clones were obtained: 37 clones from Sida spp. plants and 41 clones from Leonurus sibiricus plants. Sequence analysis indicated the presence of six bipartite begomovirus species and two alphasatellites. In Sida spp. plants we found Sida micrantha mosaic virus (SiMMV), Euphorbia yellow mosaic virus (EuYMV), and three isolates that represent new species, for which the following names are proposed: Sida chlorotic mottle virus (SiCMoV), Sida bright yellow mosaic virus (SiBYMV) and Sida golden yellow spot virus (SiGYSV), an Old World‐like begomovirus. L. sibiricus plants had a lower diversity of begomoviruses compared to Sida spp., with only Tomato yellow spot virus (ToYSV) and EuYMV (for the first time detected infecting plants of the genus Leonurus) detected. Two satellite DNA molecules were found: Euphorbia yellow mosaic alphasatellite, for the first time detected infecting plants of the genus Sida, and a new alphasatellite associated with ToYSV in L. sibiricus. These results constitute further evidence of the high species diversity of begomoviruses in non‐cultivated hosts, particularly Sida spp.     

Continued decline in tree euphorbias (Euphorbia tetragona and E. triangularis) on the Great Fish River Reserve,Eastern Cape,South Africa

A dramatic decline averaging 43% over a 4‐year period has occurred in tree Euphorbia (Euphorbia tetragona and Euphorbia triangularis) populations on the Great Fish River Reserve, South Africa. These changes are evident from data gathered by general vegetation monitoring methods as well as from a focused study of four tree Euphorbia populations. The decline from 2003 to 2007 was more marked for E. triangularis than for E. tetragona and was accompanied by a general absence of seedlings and a reduced presence of younger age classes of both species, decreasing the proportion of younger trees in the populations. The role of megaherbivores, specifically the black rhinoceros, in these changes is well established. However, the impact of baboon activity, leading to damage to tree crowns and upper branches, is also substantial, especially on E. triangularis populations. Damaged crowns were recorded significantly more often for E. triangularis than for E. tetragona, and the damage frequency increased with decreasing tree height. Thus, our work provides the first evidence that these two closely related Euphorbia species may be affected differently by herbivory.     

Electrophoretic Analysis of Isoenzymes in the Identification of Trypanosomatids of the Genus Phytomonas1

Five strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia {Euphorbia heterophylla, E. characias, E. pinea, E. hyssopifolia) and from Manihot escutenta, were cultured and compared through the electrophoretic mobility of isoenzymes of six enzymes: aspartate aminotransferase (EC 2.6.1.1), alanine aminotransferase (EC 2.6.1.2), phosphoglucomutase (EC 2.7.5.1), glucose-6-phosphate dehydrogenase (EC 1.1.1.49), glucosephosphate isomerase (EC 5.3.1.9), and malate dehydrogenase (EC 1.1.1.40). The strains could be distinguished from one another by their respective isoenzyme profiles.     

Fungal pathogens of Euphorbia heterophylla and E. hirta in Brazil and their potential as weed biocontrol agents

A two-year survey of the fungi associated with two important congeneric pantropical weeds, Euphorbia heterophylla and E. hirta, was conducted in part of their native range in southern Brazil. Sampling was concentrated mainly in Rio de Janeiro State and ten species were identified as pathogens of these weeds. Two taxa, Botrytis ricini and Uromyces euphorbiae, were common to both weed hosts. Alternaria euphorbiicola, Bipolaris euphorbiae, Melampsora sp., Oidium sp. and Sphaceloma poinsettiae were recorded only from E. heterophylla, whereas Colletotrichum gloeosporioides, Sphaceloma sp. and Sphaerotheca fuliginea were restricted to E. hirta. Botrytis ricini and Colletotrichum gloeosporioides are new records for E. hirta, and Alternaria euphorbiicola and Sphaerotheca fuliginea are new host records for Brazil. Bipolaris euphorbiae, previously identified as Helminthosporium sp., is considered to be the correct name for the causal agent of a major disease of E. heterophyllum in Brazil. The potential of these pathogens as biocontrol agents is discussed and the mycobiota associated with both these weeds worldwide is reviewed.This revised version was published online in October 2005 with corrections to the Cover Date.     

Taxonomic revision and phytogeographic studies in Euphorbia (Euphorbiaceae) in the Khorassan provinces of Iran

This study is focused on the genus Euphorbia L. in a part of northeast Iran, viz. the three Khorassan provinces. Since there are many taxa of Euphorbia in Iran which are used in different industries and have significant effects on human and non‐human life it is important to revise their taxonomy. With about 90 species, following Turkey with 91 species, Iran is the second richest country for Euphorbia in Asia. Of these, 30 species are distributed in the Khorassan provinces. This is the first comprehensive work on the genus in this region. According to ‘Flora Iranica’, there are 17 species of Euphorbia in northeast Iran, while according to our results, there are 30 species of Euphorbia in the Khorassan provinces alone. In addition to various new taxonomic and biogeographic results, a new species, viz. E. chamanbidensis, is described. Euphorbia chamanbidensis is closely related to E. aucheri, but seed micro‐morphological characters differentiate them. Two identification keys to the Euphorbia species of the studied area are provided, one based on macro‐morphological characters and another based on seed micro‐morphological characters. Phytogeographic analysis and distribution maps for all species are also presented.     

Jatrophane diterpenes from Euphorbia spp. as modulators of multidrug resistance in cancer therapy

A phytochemical investigation of the aerial parts of Euphorbia spp., considered one of the most common elements of Mediterranean landascape, led to the isolation of a large number of bioactive plant metabolites, belonging to the diterpenes family. Above all, over seventy jatrophane, modified jatrophane, segetane, pepluane, and paraliane diterpenoids, fifty of them reported for the first time, were extracted, purified and characterized from Euphorbia dendroides, Euphorbia characias, Euphorbia peplus, Euphorbia paralias and Euphorbia helioscopia. These compounds showed interesting pharmacological activities. In particular, jatrophanes, modified jatrophanes and lathyranes exhibited a potent inhibitory activity against P-glycoprotein (Pgp), a membrane protein that confers cellular ability to resist lethal doses of certain cytotoxic drugs by pumping them to the outside, thus resulting in a reduced cytotoxicity. Among the others, our chemical survey led to isolation of the most powerful inhibitors of daunomycin-efflux activity isolated to date for this class of inhibitors, named euphodendroidin D and pepluanin A. Their efficiency was found to be at least two-fold higher than the conventional modulator cyclosporin A, taken as a reference. In addition, the isolation of a high number of natural structurally-related analogues allowed us to perform Structure Activity Relationship (SAR) studies, without any chemical modification, which gave information on the key pharmacophoric elements of these new class of promising drugs. A further set of diterpene analogues, very recently isolated from sun spurge, E. helioscopia, individually investigated for their Pgp- and BCRP-inhibiting properties, appeared to be specific inhibitors of Pgp since they showed no significant activity against BCRP, thus resembling to the third-generation class of specific MDR inhibitors.     

Il Gametofito Tetramegasporiale di Tulipa Oculus-Solis St. Am. Var. Praecox (Ten.)

Summary

We take here into consideration the embryologic study of Tulipa Oculus-solis St. Am v. praecox, a species which became naturalized in the northern Sardinia, and we notice that contemporaneously to the development of the embryo-sac according to Euphorbia dulcis type (85% frequency), which was already described by Bambacioni (1931), we may have also the development according to Adoxa type (15% frequency).

We show here the hypothesis that the possibility of developping the embryo-sac according to unlike types (but genically kindred ones) is not depending upon an early or a delayed vacuolisation, caused by either external or internal casual factors, but on the contrary is the manifestation of a peculiar tendency which is connected with the particular genetic caracteristic of the Species.     

A new arborescent Euphorbia (Euphorbiaceae) from northern Somalia

Euphorbia spissa, sp. nov., a tree known from a single population on a rocky limestone slope in northern Somalia, is described and illustrated. The species is compared with the widespread E. tirucalli, as well as with E. cameronii and E. bariensis (endemics in Somalia), E. arbuscula (endemic on Socotra), and E. uzmuk (endemic in northern Yemen).     

Contributo All'Embriologia Delle Plumbaginaceae (con 103 figg. nel testo)

Riassunto

L'A. stabilisce che in Plumbago capensis Thunb., accanto allo sviluppo secondo lo schema del tipo Plumbago, si riscontra, con bassissima frequenza, un nuovo tipo di sviluppo di gametofiti 7-nucleati bipolarizzati con oosfera di natura sporiale.

Stabilisce inoltre che in Statice Limonium L. lo sviluppo del gametofito femminile avviene esclusivamente secondo il tipo Euphorbia dulcis, mentre in Armeria vulgaris W. var. maritima (Miller) Willd. esiste associazione dei due tipi di sviluppo Adoxa ed Euphorbia dulcis nel rapporto approssimativo del 3%.

Mette in evidenza che la triploidia dei nuclei calazali, caratteristica dei gametofiti di tipo Euphorbia dulcis, può determinarsi secondo due distinte modalità : o per coalescenza dei tre fusi calazali durante la terza divisione dello sviluppo (Statice Limonium), o per un processo di vera e propria cariogamia dei tre nuclei sporiali quiescenti durante lo stadio di polarizzazione 1+3 con conscguente formazione durante la storia dello sviluppo di uno stadio binucleato secondario (Armeria vulgaris var. maritima).

Riconferma infine per questa ultima pianta il numero aploide dei cromosomi n = 9.     

A newEuphorbia species from Southern Sinai

A new species,Euphorbia sanctae-catharinae A. Fayed, from the group ofE. terracina L., is described from southern mountaneous area of Sinai.     

IMI与K标本室中生于大戟科植物上链格孢属的种Ⅱ.大戟属,铁苋菜属和守宫木属上的种

本文系作者继大戟属(Euphorbia L.)、守宫木属(Sauropus B1.)和铁苋菜属(Acalypha L.)植物上链格孢属(Alternaria Nees)真菌研究(Zhang, 1995)之后,对生于大戟科(Euphorbiaceae)其它属植物上一些链格孢真菌种级分类单位评鉴结果的后续报道.内容包括:一个新种,巴豆生链格孢(A. croronicola T. Y.Zhang & J. C. David), Macrosporium compactum Cooke:对其模式标本(holotype)进行T订正、巴豆链格孢[A.crotonis kamal,Singh & Kumar]:提出关于新模式(neotype)标本的建议;对蓖麻链格孢[A. ricini(yoshii)Hansford]典型性状作了补充描述.此外,还在大戟科其它一些植物上检查到长极链格孢[A. longissima Deighton et MacGarvie]和细极链格孢[A. tenuissima(Nees ez Fr.) Wiltshire]。     

Nickel localization in tissues of different hyperaccumulator species of Euphorbiaceae from ultramafic areas of Cuba

Pantropical species of the genera Phyllanthus and Euphorbia and the Cuban endemic genus Leucocroton from the Euphorbiaceae family, were selected for nickel localization microanalysis. Scanning Electron Microscopy coupled with Energy Dispersive X-ray Microanalysis (SEM-EDX) was used for qualitative detection of nickel in the selected Ni-hyperaccumulator species: Euphorbia helenae, Leucocroton linearifolius, L. flavicans Phyllanthus orbicularis, P. discolor and P. xpallidus, all collected from Cuban ultramafic soils. The leaves and stems from the Euphorbiaceae species analyzed were the organs with higher nickel accumulation. Elemental mapping of leaves and stem tissues from these species have been compared. The highest Ni concentrations were found in the laticifer tubes of stems and the epidermis tissues of leaves in all the analyzed species, suggesting a general pattern of the Euphorbiaceae family for nickel accumulation. The high nickel concentrations and its rather homogeneous distribution found in leaves of these Ni-hyperaccumulating plants suggest a possible role in protection mechanisms against environmental stress, such as UV irradiation.