Orobanche variegata — eine weitere Tetraploide der SektionOrobanche

The MediterraneanOrobanche variegata has n = 38. This is the third tetraploid taxon known from sect.Orobanche.

     

Bemerkungen zur Cytologie einiger Arten der GattungSilene (Caryophyllaceae) aus Zentralgriechenland und Kreta

The chromosome numbers of several Greece species of the genusSilene L. from natural habitats are reported for the first time:S. sieberi, S. niederi, S. radicosa subsp.rechingeri, S. oligantha, S. skorpilii, S. schwarzenbergeri andS. fruticulosa. All species are diploid with 2n = 24 chromosomes, including 0, 2 or 4 SAT-chromosomes;S. niederi has B-chromosomes.

     

Die Chromosomenzahlen von tschechoslowakischen Arten der GattungKnautia L. (Dipsacaceae)

Die Chromosomenzahlen von den tschechoslowakischen Sippen der GattungKnautia L. sind angegeben:K. drymeia Heuffel subsp.drymeia—2n = 40 (41,42),K. slovaca ?těpánek— 2n = 20,K. arvensis (L.)Coulter subsp.arvensis—2n = 20, 40 (39, 41),K. arvensis (L.)Coulter s. 1.—2n = 20,K. kitaibelii (Schult.) Borbás—2n = 20 (39, 41),K. dipsacifolia Kreutzer subsp.dipsacifolia—2n = 60,K. dipsacifolia agg.—2n = 40, 50, 60. Keine taxonomisch wertvolle morphologische Unterschiede zwischen diploiden und tetraploiden Zytotypen vonK. arvensis subsp.arvensis wurden gefunden. Für die Populationen von Pflanzen, deren Morphologierauf Kreuzung oder Introgression zwischen tetraploiden Sippen (K. arvensis subsp.arvensis—4x,K. drymeia subsp.drymeia, K. kitaibelii undK. dipsacifolia agg.) zeigt, wurden ím Einklang mit dieser Voraussetzung die tetraploiden Chromosomenzahlen—2n = 40 (39, 41)— festgestellt. Einige ungelöste taxonomische Fragen hauptsächlich über die diploiden Populationen vonK. arvensis s. l. in Böhmen und überK. dipsacifolia agg. in den Westkarpaten werden diskutiert.     

A reappraisal ofPelargonium sect.Ligularia (Geraniaceae)

A study of 33 species ofPelargonium sect.Ligularia reveals four basic chromosome numbers, x = 8, 9, 10, and 11, and variation in chromosome size. From evidence of karyology and hybridization attempts, proposals are made to divide the section into smaller groups and to transfer some species to other sections.     

Zwergstrauchige Arten der FlechtengattungCaloplaca

The frutescent species of the lichen genusCaloplaca are usually united in sect.Thamnoma, but they do not form a natural group. They are derived from different species groups within sect.Gasparrinia from different parts of the world, presumable from species having scleroplectenchymes in cortex and medulla. The algal cells are concentrated between the scleroplectenchymatic strands in large and dense groups, from where medullary plectenchyme extends to the cortex and forms characteristic pseudocyphellae there.—Most of the species seem to be ornithocoprophilous; they grow on rocks along marine coasts where much fog is induced by cold currents.—Caloplaca cribrosa is endemic in Tasmania and New Zealand,C. regalis and the doubtfulC. ambitiosa belong to the antarctic element.C. fragillima from central Chile seems to be propagated by thallus fragments.C. coralloides andC. thamnodes are endemic to California and Baja California respectively.C. cladodes from the Rocky Mountains deviates in many characteristics from the other species i.a. by it different ontogenetic development, reduced spore septum, and cementing amyloid polysaccharides within the scleroplectenchymatic strands. The African species are characterized by their distinctly dorsiventral lobes and usually possess oil cells in some of the paraphyses.Caloplaca bonae-spei, C. fragillima andC. thamnodes are new to science.

     

A cytological study ofPelargonium sect.Eumorpha (Geraniaceae)

The chromosome numbers of seven species ofPelargonium sect.Eumorpha have been determined from material of known wild origin, and karyotypic comparisons have been made. Within the section there is variation in basic chromosome number (x = 4, 8, 9, 11), variation in chromosome size, and two species have polyploid races. The three species with chromosome numbers based on x = 11 have the smallest chromosomes (1.0–1.5 µm); chromosomes are larger (1.0–3.0 µm) in the other species.P. elongatum has the lowest chromosome number in the genus (2n = 8).P. alchemilloides is exceptional in that it has four cytotypes, 2n = 16, 18, 34 and 36, and the form with 2n = 36 has large chromosomes (2.0–5.0 µm). Evidence from a synthesized hybrid suggests thatP. alchemilloides with 2n = 16 may be of polyploid origin. The three species based on x = 11 appear to be more closely related to species from other sections ofPelargonium that have the same basic chromosome number and small chromosome size, rather than to other species of sect.Eumorpha.     

Acht neue Arten der GattungAnthemis (Compositae) aus Persien

The following species are described as new:Anthemis mazandaranica in N. and NW. Iran is allied toA. coelopoda; A. moghanica in NW. Iran is close toA. candidissima andA. sintenisii; A. atropatana also in NW. Iran is similar toA. hyalina; A. gracilis in W. Iran is close toA. plebeia; A. bushehrica in SW. Iran is similar toA. susiana; andA. rhodocentra in S. and E. Iran and in Pakistan is akin toA. austro-iranica, A. gayana, andA. kandaharica.

Anschrift des Herausgebers: Hofrat Univ.-Prof. Dr.Karl Heinz Rechinger, Beckgasse 22, A-1130 Wien, Österreich.     

Untersuchungen zur Karyologie und Mikrosporogenese vonPelargonium sect.Pelargonium (Geraniaceae)

The chromosome numbers of the 24 species of sect.Pelargonium were determined from field collected and cultivated plants of known localities in S. Africa. Twelve species are diploid (2n = 22), eight tetraploid (2n = 44), one hexaploid (2n = 66), and three octoploid (2n = 88). The chromosome numbers correlate well with the proposed subdivision of sect.Pelargonium. Its chromosomes are relatively small (1.0–1.5 µm) in comparison to most of the other sections, and its diploid karyotype is considered to be primitive. The occurrence of the basic number x = 11 in this section, in other sections of the genus, and in related genera (Monsonia, Sarcocaulon) leads to the conclusion that x = 11 probably is basic for the whole genus. — The pollen meiosis, microsporogenesis and pollen fertility of the diploid species is normal, with the exception of one, possibly young taxon from the Greyton Nature Reserve. The tetraploid species could be of autoploid origin, the higher polyploids exhibit a mixed auto-alloploid nature. — The 20 diploid and tetraploid species have a relatively small distribution range, most of them occur in the SW. Cape Province of South Africa. This area may therefore be considered as the centre of origin of the genus. Three of the four high polyploid species occupy rather large areas.

Untersuchungen zur Karyologie und Mikrosporogenese der GattungPelargonium, 1.     

Biological control of Orobanche spp. with Phytomyza orobanchia, a review

This review summarises theavailable information on the biocontrol agentPhytomyza orobanchia Kalt. (Diptera, Agromyzidae). It gives an overview of a rareexample of weed biocontrol using insects in aninundative approach. A high diversity ofphytophagous insects has been collected onparasitic weeds of the genus Orobanche(Orobanchaceae). For biological control of Orobanche spp., only insects like P. orobanchia whose host range is restricted toOrobanche spp. are of interest. Of the140 Orobanche spp. described in total,P. orobanchia is reported from 21 species. The larvae of P. orobanchia minein Orobanche shoots and capsules. As aconsequence, a natural reduction of Orobancheseed production by 30 to almost 80%has been reported from different countries. Theefficacy of P. orobanchia under naturalconditions is limited by low temperatures, cultural practices and natural enemies. Tostrengthen the natural population and itsimpact, inundative releases of P. orobanchia adults at the beginning of Orobanche emergence have to be undertaken. Different methods for the application of P. orobanchia in biocontrol of Orobanche spp. have been developed in theformer Soviet Union. Releases of 500 to 1000adults/ha resulted in a reduction of up to 96%of the Orobanche seed production.However, due to the 10 to 15 year longevity ofOrobanche seeds, further infestationswill occur in the following cropping seasons.Consequently, releases of P. orobanchiahave to be repeated continuously over severalyears to reduce the infestation to a tolerablelevel.     

Delimitation ofPelargonium sect.Glaucophyllum (Geraniaceae)

Pelargonium otaviense Knuth andP. spinosum Willd. are excluded from sect.Glaucophyllum, whileP. grandiflorum (Andr.)Willd.,P. patulum Jacq. andP. tabulare (Burm. f.)L'Hérit. of sect.Eumorpha are included. Sect.Glaucophyllum is characterized by green to glaucous vegetative organs and zygomorphic white to pink corolla with five narrow petals. All the species have an identical pollen and chromosome morphology, the same basic chromosome number (x = 11) and similar flavonoid patterns. A close relationship between sect.Glaucophyllum and sect.Pelargonium is indicated by the occurrence of natural hybrids and concordant characters. Isorhamnetin and luteolin have been detected in the genus for the first time.     

Cephalodiate Arten der GattungLecidea sensu lato (Ascomycetes lichenisati)

(1) The ability to produce cephalodia is usually a genus-specific character in lichens. (2)Lecidea shushanii Thoms., is a member of the genusTephromela, closely related toT. aglaea. It is not clear, whether or not the cephalodia of this taxon are true cephalodia or colonies of epiphytic cyanobacteria and whether or notLecidea shushanii is an independent species. (3)Lecidea dovrensis Nyl., is, in contrast to the traditional concept, not conspecific withLecidea alpestris Sommerf., but an earlier name forLecidea pallida Th. Fr. (4)Lecidea dovrensis is described in some detail. Chemically the species is characterized by the presence of isousnic acid (previously unknown in lecideoid lichens). It is restricted to areas north of the 60th parallel with an oceanic climate. (5) In connection with the attempt to clarify the taxonomic relationships ofLecidea dovrensis, figures of ascus apical structures of the following species are given (marked by an asterisk are genera where we found discrepancies with published data):Austrolecia antarctica, Catillaria chalybeia, Lecidea alpestris, L. caesioatra, L. limosa, Lecidoma demissum, Koerberiella wimmeriana, Micarea assimilata, M. crassipes, M. melaenida, M. prasina, Pilophorus robustus, Placodiella olivacea, Placolecis opaca, Porpidia trullisata, Protoblastenia rupestris, Psilolechia lucida, Psorula rufonigra, Squamarina gypsacea, Xanthopsorella texana. (6) Among crustaceous lichens we find no groups related toLecidea dovrensis. We supportTimal's concept of including this species in the genusPilophorus. Pilophorus, as well asLecidea dovrensis is characterized by the same ascus type, by a similar structure of thallus, cephalodia, paraphyses, and ascocarp (although there is no pseudopodetium developed inLecidea dovrensis), and the presence of isousnic acid. In addition, both taxa are restricted to cool oceanic climates and non-calciferous substrates. The following combination is proposed:Pilophorus dovrensis (Nyl.)Timdal, Hertel & Rambold, comb. nova. (7) The species of theLecidea alpestris-group form an independent genus, probably near toAustrolecia Hertel.

Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.     

Recent advances in the biocontrol of Orobanche (broomrape) species

Parasitic broomrapes (Orobanche spp.) are majoruncontrolled weeds in the Mediterranean regions of Europe and the NearEast causing major losses to vegetable, grain legume, and sunflowercrops. Selective herbicides alone cannot provide persistent, season-longcontrol of these parasites, and much methyl bromide is used for theircontrol, where affordable. Thus they are excellent targets forbiocontrol. The recent progress by the COST 816 Orobancheworking group in this area is reviewed herein. Natural infestation bythe fly Phytomyza orobanchia of seed capsules of Orobanchecrenata parasitising faba bean halved Orobanche seedproduction while inundative releases of adults reduced it to 5%of viable seeds. The fungi Fusarium arthrosporioides E4a andF. oxysporum E1d, as well as strains of bacteria were isolatedfrom diseased, juvenile, Orobanche flower stalks. They arepathogenic to O. aegyptiaca, O. crenata and O. ramosaon most vegetable crops. A F. oxysporum f. sp.orthoceras was specifically pathogenic to O. cumana onsunflowers. All were used in various experiments with a modicum ofsuccess. Methods were developed to formulate isolated mycelia, whichcould eventually allow the use of transgenic hypervirulent pathogens inasporogenic (deletion) mutants (as a failsafe against spread).Mycotoxins were also isolated from different Fusarium and otherfungal species that kill Orobanche, and are being consideredfor direct use, or to augment other strategies. All threeFusarium spp. used have been transformed with gusand/or gfp genes allowing tracing their movement in theenvironment, and opening the way to future transformations tohypervirulence.     

Horizontal gene transfer of a plastid gene in the non-photosynthetic flowering plants Orobanche and Phelipanche (Orobanchaceae)

Plastid sequences are among the most widely used in phylogenetic and phylogeographic studies in flowering plants, where they are usually assumed to evolve like non-recombining, uniparentally transmitted, single-copy genes. Among others, this assumption can be violated by intracellular gene transfer (IGT) within cells or by the exchange of genes across mating barriers (horizontal gene transfer, HGT). We report on HGT of a plastid region including rps2, trnL-F, and rbcL in a group of non-photosynthetic flowering plants. Species of the parasitic broomrape genus Phelipanche harbor two copies of rps2, a plastid ribosomal gene, one corresponding to the phylogenetic position of the respective species, the other being horizontally acquired from the related broomrape genus Orobanche. While the vertically transmitted copies probably reside within the plastid genome, the localization of the horizontally acquired copies is not known. With both donor and recipient being parasitic plants, a possible pathway for the exchange of genetic material is via a commonly attacked host.     

Use of random amplified polymorphic DNA (RAPD) markers in the study of the parasitic weed Orobanche

Despite the tremendous economic impact of broomrapes (Orobanche spp.) on agriculture in many countries little is known of the pattern of genetic variation within this group of parasitic weeds. The present paper describes the use of RAPD markers for the study of five Orobanche species in agricultural fields in Israel. Pronounced genetic differentiation was found between the species, and RAPD markers were raised for the identification of each of them. Southern-hybridization patterns of RAPD products of the various species were used to confirm the interpretation. The same markers were valid both for broomrapes collected in agricultural fields and for those collected in natural habitats. The validity of the markers found for O. cumana and O. crenata was confirmed on plants of the same species that were collected in Spain. Parsimony analysis of 86 RAPD characters produced a tree that clearly distinguishes between the five studied Orobanche species, separates the two Orobanche species belonging to sect. Trionychon from those belonging to sect. Osproleon, and supports the separation of O. cumana from O. cernua and of O. aegyptiaca from O. ramosa.     

Biosystematic studies inTulipa sect.Eriostemones (Liliaceae)

Evolutionary relationships and infra- and interspecific variability within the species ofTulipa sect.Eriostemones Boissier were studied. Measurements of 35 morphological characters were used for principal component and canonical variate analyses. Crossing experiments and chromosome counts were carried out. Two axes of morphological variation were encountered within the principal component plot. Variation of subsect.Biflores was traced along one axis, the species of subsect.Australes as well asSaxatiles were found along the other axis. The nomenclature of names of subsect.Biflores was considered on the basis of their geography, specific morphological characteristics and polyploidy. Conspecificity of names of all species was tested based on both morphology and crossability.     

Revision ofVerbesina sect.Pseudomontanoa (Asteraceae)

Verbesina sect.Pseudomontanoa is revised. The last treatment of the group byRobinson & Greenman (1899) recognized 5 species; the present treatment recognizes 12 species, 3 of which (V. breedlovei, V. cronquistii andV. olsenii) are described as new. A key to species, phyletic diagram and distribution maps are provided.     

Karyological studies onGentiana sect.Chondrophyllae (Gentianaceae) from China

Nineteen populations of fifteen species ofGentiana sect.Chondrophyllae from China were observed cytologically.Gentiana alsinoides, G. anisostemon, G. asterocalyx, G. exigua, G. heterostemon, G. intricata, G. praticola, G. pseudoaquatica, G. spathulifolia, andG. subintricata all had the same chromosome number of 2n = 20 (or n = 10), whereasG. piasezkii had 2n = 36,G. squarrosa 2n = 38,G. prattii 2n = 18,G. aristata 2n = 14 (n = 7), andG. heleonastes 2n = 12. All these chromosome numbers are documented here for the first time, except forG. squarrosa, where it is a new number report. The basic numbers of x = 6, x = 7 and x = 19 are new for the section. Karyotype analyses of some species revealed that, except for a few cases, the species examined mainly had metacentric chromosomes. 2n = 20 = 2m(SAT) + 18m was found to be the main type of karyotype for the species with 2n = 20. Chromosomal evolution and its mechanism in this section are also discussed.     

Synopsis ofVerbesina sect.Ochractinia (Asteraceae)

A taxonomic revision ofVerbesina sect.Ochractinia is presented. 40 species plus 7 additional infraspecific taxa are recognized. A table of the distribution of the species, key to the species and synonymy are included. Relationships to other sections ofVerbesina and species relationships within sect.Ochractinia are discussed.     

Zwei neue Arten der GattungSaponaria (Caryophyllaceae) aus Afghanistan und Pakistan

Saponaria stenopetala sp.n. in Eastern Afghanistan is close toS. pachyphylla Rech. f. andS. subrosularis Rech. f.—The nearest allies ofS. makranica sp.n. from Western Pakistan and Southeastern Iran areS. kermanensis Bornm. andS. floribunda (Kar. & Kir.)Boiss.

Flora Iranicae praecursores 36–37. — Praecursores praecurrentes in Pl. Syst. Evol.139, 313–317 (1982).     

Pollen morphology inLinum sect.Macrantholinum

Pollen of the two distylous species which make upLinum sect.Macrantholinum differs from that of other distylous species in the genus in being multiporate and in having much more modest differences in exine sculpturing between grains from long- and short-styled plants. Pollen morphology does not help in relating the two species to others in the genus but does support their retention in a separate section.