A further note on the relationships of the EuropeanLinum hologynum and the Australian species ofLinum (Linaceae)

The diploid chromosome number for the EuropeanLinum hologynum and the haploid number for the AustralianL. monogynum is 42 and appears to establish a new and distinctive base number for sect.Linum. The possession by these two species and by the AustralianL. marginale of multiporate pollen and united styles, a unique combination of features in sect.Linum, may warrant the establishment of a new subsection in that section to accommodate the three species.     

Chromosome counts inPosidonia (Posidoniaceae)

The five species ofPosidonia occuring in Western Australia all have a diploid chromosome number of 20.     

Karyosystematics and evolution of AustralianAnnonaceae as compared withEupomatiaceae,Himantandraceae, andAustrobaileyaceae

Chromosome counts are presented for 12 genera and 20 species of AustralianAnnonaceae (all diploid with 2n = 16 or 18; Table 1) and two species ofEupomatiaceae (2n = 20, partly from Papua New Guinea). Detailed studies on interphase nuclear structure, condensing behaviour of chromosomes, and fluorochrome and Giemsa C-banding patterns also includeHimantandraceae (Galbulimima) andAustrobaileyaceae. — Eupomatiaceae completely correspond withAnnonaceae karyologically, their base number 2n = 20 is interpreted to have evolved from 2n = 18 by ascending dysploidy from common ancestors.Eupomatia laurina andE. benettii differ in DNA and constitutive heterochromatin (hc) quantity; their evolution from high to low DNA content probably corresponds to general progressions inMagnoliidae. Austrobaileya has nuclei of the presumably primitive Tetrameranthus type which is closely related to that ofGalbulimima and several other primitive taxa inMagnoliidae. Karyomorphology and other characters support the maintainance of two main branches within theMagnoliidae, Laurales andMagnoliales, withAustrobaileya probably intermediate; theWinteraceae appear more remote.—InAnnonaceae the reestablishment ofAncana is underlined by its chromosome number (2n = 18) the unexpected and specialized disulcate pollen, and various morphological characters which point to a close alliance with the Australian endemic generaFitzalania andHaplostichanthus (also disulcate) and the American genus pairSapranthus/Desmopsis; they are united in the provisionalSapranthus tribe, with a more distant position toFissistigma s. str. (2n = 16). AustralianAnnonaceae exhibit a high generic and a low species diversity; they can be considered as an ± old and partly impoverished outpost of the family with phytogeographical relationships to Asia, Africa and America.—On the base of field observations three main types of floral development inAnnonaceae are proposed, the most elaborated one found in the fly pollinated genusPseuduvaria. The growth form change from shrubs to lianas during the ontogeny ofDesmos andMelodorum, the vegetative propagation of anAncana species and the ecological and evolutionary patterns of the taxa investigated are discussed.     

Chromosome numbers and their systematic implications in Australian marine angiosperms: ThePosidoniaceae

Somatic chromosome numbers of 2n = 20 are reported for all eight species of AustralianPosidonia: P. angustifolia, P. australis, P. coriacea, P. denhartogii, P. kirkmanii, P. ostenfeldii, P. robertsonae, andP. sinuosa. All species apparently have five larger and five smaller pairs of chromosomes. There is no evidence that speciation inPosidonia, which is relatively prolific in comparison to other seagrasses, is accompanied by change of chromosome number.     

Notes on the life histories of Boergesenia and Valonia (Siphonocladales,Chlorophyta)

Life history studies were carried out with isolates of Boergesenia forbesii (from Western Australia), Valonia fastigiata (Hawaii) and V. utricularis (Canary Islands, Mediterranean Sea) cultivated under laboratory conditions. Ploidy levels of nuclei were identified by micro spectrophotometric DNA content measurements after Feulgen staining. Fundamentally, the life history in both genera is diplohaplontic. Autodiploidization phenomena have been observed favoring the diploid generation. In contrast to other genera of the Siphonocladales s. str. producing biflagellate diploid zoospores (e.g. Ernodesmis, Boodlea), Valonia develops haploid and diploid zoospores with four flagella. No diploid zoospores were observed in Boergesenia.     

Intrapopulation variation in the breeding system ofVillarsia lasiosperma (Menyanthaceae), a distylous species

The restricted perennial diploid herb,Villarsia lasiosperma, of southwestern Western Australia has distylous flowers with dimorphism in style and stamen length, stigma morphology, and pollen size. In order to assess the presence and nature of an incompatibility system in this species, a crossing program was carried out using 17 plants grown from seeds collected in two field populations. Pollen stainabilities of these plants mostly exceeded 95%. Mean seed-set of Longs following intermorph pollinations was c. 24 seeds per pollination and for Shorts was c. 16 seeds per pollination. Approximately three-quarters of the Longs and Shorts produced no seeds after self-pollination; the remainder produced very few seeds following such pollinations. No Shorts produced seeds after intramorph cross-pollinations. However, about half the Longs exhibited various levels of weakened intramorph incompatibility, with mean seed-sets following intramorph cross-pollinations up to half the mean seed-sets following intermorph pollinations. In the behavior of Longs, the incompatibility system ofV. lasiosperma differs from the idealized distylous breeding system, but resembles that of a purported close relative,V. exaltata of eastern and southeastern Australia.     

Karyotaxonomical analysis in the genusAngelica (Umbelliferae)

Morphometric karyotype characters were studied in 25Angelica spp. (Umbelliferae, Apioideae) and in one species of the related genusTommasinia. For three species the chromosome numbers are new. In our study the majority of the species investigated are diploids with 2n = 22, some are tetraploids with 2n = 44 (for these tetraploids also diploid cytotypes are reported in the literature). Among the diploid species,A. miqueliana has a distinct karyotype consisting of submetacentric and acrocentric chromosomes only, the remaining diploids with 2n = 22 as well as tetraploids with 2n = 44 have rather symmetrical karyotypes, consisting of metacentric and submetacentric chromosomes. The very different chromosome number 2n = 28 has been found inA. gmelinii. Its karyotype includes two distinct groups of chromosomes: 8 pairs of rather large metacentrics and submetacentrics and 6 pairs of very short and asymmetrical chromosomes. Chromosome numbers and structures appear to be useful in the taxonomy of some intrageneric taxa inAngelica.     

Systematics of AustralianLepidium species (Brassicaceae) and implications for their origin: Evidence from IEF analysis of Rubisco

Variation in subunit polypeptide composition of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from native AustralianLepidium taxa was analyzed by isoelectric focusing (IEF). Species of grexMonoplocoidea on the one hand, and species of gregesPseudoruderalia andPapillosa on the other, were well separated by Rubisco IEF patterns. The protein data suggest grexMonoplocoidea to be placed in sect.Monoploca whereas gregesPseudoruderalia andPapillosa should be integrated into sect.Dileptium. We suggest that the Rubisco type of American and/or AsianLepidium species was contained in those plants migrating to Australia and evolving into the recent native Australian species. Fossil pollen records and vegetation history indicate that the origin ofLepidium in Australia was restricted to the late Tertiary of Quaternary. Data presented in this study fit best with an immigration by long-distance dispersal of seeds by birds from Asia and/or from South America.     

On the origin ofVeronica persica (Scrophulariaceae)—a contribution to the history of a neophytic weed

A character analysis reveals a clearly intermediate position of the tetraploidV. persica (2n = 28) between the two diploid speciesV. polita andV. ceratocarpa (both 2n = 14) which are morphologically rather different and have been placed by several authors in different sections of the genus.V. ceratocarpa is native to subhumid deciduous forests of the Caucasus and of the Elburz mountains (N. Iran);V. polita has its centre of variation in the Elburz range where it grows in therophyte habitats. Three other closely related species,V. bungei, V. siaretensis, andV. francispetae, are endemic to the Elburz range which is the main centre of diversity and variability of theV. agrestis group. This comprises all the above mentioned species and also two more European weeds:V. agrestis andV. opaca. Veronica polita, was probably originally native to open places in deciduous mountain forests, before becoming a weed in neolithic times and migrating to Europe; nowadays it has an almost world-wide distribution. The allotetraploidV. persica combines the ecological characters of its parents, the slightly xerophyticV. polita and the more mesophyticV. ceratocarpa, thus being preadapted to become a highly successful weed with a large ecological range. It has spread rapidly almost all over the world since the early 19th century.Dedicated to Hofrat Univ.-Prof. DrKarl Heinz Rechinger on the occasion of the 80th anniversary of his birthday.     

Karyosystematic studies on threeCrepis species (Asteraceae) endemic to Greece

This work examines the cytogeographical distribution, the morphological characters, and the karyotypes of threeCrepis species endemic to Greece (C. sibthorpiana, C. incana, andC. heldreichiana). C. sibthorpiana is diploid (2n = 2x = 8),C. incana is diploid (2n = 2x = 8) and tetraploid (2n = 4x = 16, 17), andC. heldreichiana is always dekaploid (2n = 10x = 40). The Giemsa positive bands, usually pairs of dots, are mainly centromeric inC. incana, while they are terminal inC. sibthorpiana (on the short arm of all chromosomes) and inC. heldreichiana (on both arms of all chromosomes). Intercalary C-bands are scarce and usually variable within karyotypes, individuals, and species. The most variable karyotype both in Feulgen and Giemsa preparations is that ofC. incana, in which also supernumerary chromosomes were observed, which are polysomic to standard set members. On the basis of morphological and karyological data the evolutionary relationships among the threeCrepis taxa are discussed.     

C-banding patterns in the AustralianBulbine (Liliaceae): The annual group,B. semibarbata s. lato

Chromosome C-band patterns have been studied in 34 populations of the Australian annualBulbine group, which comprises 4x (2n = 26, 28), 8x (2n = 52, 54) and 12x (2n = 78) populations. The 2n = 26B. semibarbata populations have a simple, low heterochromatin pattern with very minor polytypic variation. The 2n = 28 populations, corresponding morphologically to a group given separate status asB. alata, are similar in pattern but exhibit pronounced enhancement of telomeric and, more particularly, centromeric dot bands. NOR heterochromatin and satellites are difficult to identify inB. alata but appear to occur in different positions from the 26-chromosome karyotype. Eastern Australian 8 x patterns are consistent with a proposed hybrid ancestry,B. semibarbata ×B. alata. Annual and perennial C-band profiles in the AustralianBulbine are discussed briefly in relation to the additive and transformation models of heterochromatin evolution and to the possible adaptive significance of variation in heterochromatin content.Cytoevolution in the AustralianBulbine 2; for part 1 see Pl. Syst. Evol.157, 201–217.     

Systematics and karyoevolution inMagnoliidae:Tetrameranthus as compared with otherAnnonaceae genera of the same chromosome number

First generic chromosome counts reveal the base number x=7 for the generaTetrameranthus andRollinia. T. umbellatus from the Peruvian Amazon is diploid (2n=14),T. duckei from Brazil (Manaus) is tetraploid (2n=28). In the NeotropicsRollinia (7 species counted) has developed diploid to octoploid taxa (2n=14, 28, 42, 56). Counts of 7 South AmericanAnnona species are presented for comparison (2n=14, 28). The West AfricanCleistopholis patens has 2n=14. The Asian genusMezettia: 2n=14 and the neotropicalGuatteria tribe: 2n=28 are also revised. A detailed karyomorphological comparison, including karyotypes, banding patterns, condensing behaviour of chromosomes and structure of interphase nuclei reveals that the closely related generaAnnona andRollinia are almost identical in their diploid genomes, whereas the polyploid ones differ in their heterochromatin (=hc) composition and number of NO-chromosomes.Cleistopholis, Mezettia and theGuatteria tribe are karyologically and systematically distinct from each other and fromAnnona/Rollinia. Tetrameranthus as compared with the karyomorphology of about 60 other Annonaceous genera has a very peculiar and unusual karyomorphology which underlines its isolated position. Nuclear structures are almost identical in the African genusUvariopsis (2n = 16) and partly similar in theGuatteria tribe; both also share some morphological similarities and possibly are related. From a comparison ofTetrameranthus with several nuclear types within theMagnoliidae, a new model of chromosome evolution in primitive Angiosperms is suggested. In respect to their eco-morphological differentiation the genera investigated differ strongly from each other.Dedicated to Prof. Dr. K.-H.Rechinger on the occasion of His 80th birthday.     

Cytotaxonomy and breeding system of the genusBiscutella (Cruciferae)

Chromosome counts were determined for 46 populations ofBiscutella representing 28 taxa. The genus was found to contain diploid taxa with 2n = 12, 16 and 18, tetraploid taxa with 2n = 36 and hexaploid taxa having 2n = 54.B. laevigata L. s. l. consists of diploid and tetraploid populations which are poorly differentiated morphologically. TetraploidB. laevigata s. l. and hexaploidB. variegata Boiss. & Reuter (s. l.) are characterized by chromosomal instability. The variation in chromosome numbers and the occurrence of polyploidy is discussed in relation to the taxonomy of the genus. An investigation of the breeding system showed that most of the annual species were self-compatible and partly inbreeding and most of the perennial species self-incompatible and, therefore, outbreeding, while one annual species,B. cichoriifolia Loisel., showed both systems.     

Karyological and chemotaxonomical studies of the hybridPelargonium incarnatum ×P. patulum (Geraniaceae) and its parents

Pelargonium incarnatum is a tetraploid species (2n = 40) andP. patulum is diploid (2n = 22). A natural hybrid, collected at the same locality as the parent species, has 2n = 42 chromosomes. The meiosis of the hybrid is practically normal and its pollen fertility corresponds to that ofP. incarnatum. The flavonoid patterns of the parent species and the hybrid are very similar. The origin and phylogenetic implications of this intersectional hybrid are discussed.     

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.     

Stigma morphology in distylous and non-heterostylous species ofVillarsia (Menyanthaceae)

Stigma morphology was examined with the SEM in 14 of the 16 species ofVillarsia. In nine of the ten distylous species studied, stigmas of the floral morphs were strongly dimorphic in length, shape, configuration of the receptive surface, and in the size and density of their papillae. Thrum stigmas ofVillarsia, in contrast to those of most other distylous species, are not simply smaller versions of the conspecific pin stigmas, but generally exhibit an array of morph-specific characters. Thrum stigma lobes may be broader than those of pins, they may have undulate margins, lobes subdivided into secondary lobes, papillae more extensively distributed than in pins, and various combinations of these traits occur. The traits that distinguish thrum from pin stigmas achieve an increase in the receptive area and may enhance more efficient pollen capture by the shorter and less accessible thrum stigmas. The morphogenesis of the stigma shape dimorphism appears to involve processes more complex than inhibition of elongation in thrum styles. InVillarsia, the stigma dimorphisms are species-specific. No correlations were found between morphologies of the stigma and the different breeding systems in distylous species. Stigmas of the four non-heterostylous species examined resemble the thrum stigma type found in most distylousVillarsia species.     

Stylosanthes sp. aff.S. scabra: a putative diploid progenitor ofStylosanthes scabra (Fabaceae)

Stylosanthes sp. aff.S. scabra is an undescribed taxon showing affinities with the allotetraploid speciesS. scabra, but distinct in a number of attibutes. Several collections show potential as forage for clay soils in northern Australia. Twelve accessions have been analysed using STS (sequence-tagged-sites) as genetic markers, and they all displayed STS phenotypes of typical diploid species. Taking into account their morphological similarities, the STS analysis provides strong evidence thatStylosanthes sp. aff.S. scabra might be a diploid progenitor of the allotetraploidS. scabra. This speculation was supported by cytological examinations. Somatic chromosome numbers of two of these accessions were counted and both were found to be diploid (2n = 20). The level of polymorphism among the 12Stylosanthes sp. aff.S. scabra accessions, estimated using randomly amplified polymorphic DNA (RAPD) as markers, was 7.8%, and the dissimilarity value betweenStylosanthes sp. aff.S. scabra andS. viscosa (the other putative progenitor ofS. scabra) was 89%.     

Über zwei diploide,in Südwest-Anatolien endemische Arten aus dem Komplex derVeronica cymbalaria (Scrophulariaceae)

Veronica lycica Lehm. is a distinct, diploid member of theVeronica cymbalaria group, endemic in Lycia (S.W. Anatolia). Closely related is the newV. stamatiadae M. Fischer etW. Greuter which is also diploid and seems to be restricted to the small Greek island Ro close to the South coast of Lycia. The chromosome numbers for both species are reported for the first time (2n = 18).

Untersuchungen über den PolyploidkomplexVeronica cymbalaria agg., II. — Der erste Beitrag dieser Serie:Fischer (1975).     

Distyly and incompatibility inVillarsia congestiflora (Menyanthaceae), with comparative remarks onV. capitata

The Western Australian annual of restricted distribution,Villarsia congestiflora, has distylous flowers and pollen-size heteromorphism. Results of a crossing program indicate that this species is strongly self-incompatible, that crosses among individuals of the same morph produce little or no seed, and that intermorph crosses produce copious seed. The species shares a number of morphological and ecological traits withV. capitata, another distylous, self-incompatible annual species of Western Australia with a greater area of distribution. Artificial hybrids between the two, however, showed reduced pollen stainability. Both species combine a number of specialized morphological features with a breeding system that is primitive for the familyMenyanthaceae.     

Die Chromosomenzahlen der in Mitteleuropa vorkommenden Arten vonOrobanche sect.Orobanche

The chromosome numbers of five species ofOrobanche sect.Orobanche (O. alsatica, O. laserpitii-sileris, O. loricata, O. salviae, O. teucrii) are reported for the first time and previous counts could be verified in ten other species. Now the chromosome numbers of all species of sect.Orobanche occurring in Central Europe are known: they are diploid (2n = 38) with the exception ofO. gracilis (tetra- and hexaploid, aneusomatic).