A phylogenetic study ofPolygonum sect.Tovara (Polygonaceae) based on ITS sequences of nuclear ribosomal DNA

Polygonum sect.Tovara comprises three morphologically very similar species;P. virginianum,P. filiforme, andP. neofiliforme. Sequences of internal transcribed spacers (ITSs) of nuclear ribosomal DNA of these were determined to examine phylogenetic relationships and the levels of differentiation among them. The size of ITS 1 was 241 bp inP. filiforme andP. neofiliforme, and 242 bp inP. virginianum. The size of ITS 2 was 243 bp, and that of the 5.8S rRNA coding region was 163 bp. The ITS sequences clearly separate North AmericanP. virginianum from the eastern Asian species. Nucleotide divergence between them ranges from 3.3% to 3.8% for ITS 1 and from 9.3% to 10.7% for ITS 2. The molecular data also revealed that two eastern Asian species are closely related but should be treated as distinct species.     

Flavonoid chemistry ofPolygonum sect.Tovara (Polygonaceae): A systematic survey

Polygonum sect.Tovara includes three controversial species;P. virginianum, P. filiforme, andP. neofiliforme. The flavonoid chemistry of these was examined to provide additional information on their delimitation and levels of differentiation. Eight flavonoid compounds were isolated and identified, all of which were 3-O-glycosides of the flavonols kaempferol, quercetin, and myricetin, and their acylated derivatives. Although they exhibit relatively simple flavonoid profiles, the three taxa are readily distinguished by their flavonoid constituents. In addition, they show fundamental differences in flavonol types and glycosylation patterns. These results, in conjunction with evidence from the morphology, strongly suggest thatP. virginianum, P. filiforme, andP. neofiliforme are closely allied but distinct species.     

Flavonoid sequestration by the common blue butterfly Polyommatus icarus: quantitative intraspecific variation in relation to larval hostplant,sex and body size

Common blue butterflies (Polyommatus icarus) sequester flavonoids from their larval food and store these pigments as part of their adult wing colouration. Insects were reared on 10 different diets to assess effects of host plants on variation in flavonoid sequestration in this moderately polyphagous butterfly. Rearing experiments revealed an unexpectedly large gradient in flavonoid richness, ranging from individuals with high flavonoid loads (reared on inflorescences of Medicago sativa, Trifolium repens, T. pratense) to butterflies which contained almost no such pigments (fed with foliage of M. sativa or Robinia pseudoacacia). Flavonoid sequestration was much more effective from natural hostplants than from experimentally offered diets which would not be accepted in the field. Female butterflies on average sequestered almost 60% more flavonoids than males. This sex difference was more pronounced on natural than on experimental diets. Flavonoid load was significantly and positively related to dry mass and forewing length as two important fitness correlates of butterflies. This correlation was particularly strong on experimental diets (i.e. under constraining conditions for development). On natural hostplants, in contrast, when butterflies generally were flavonoid-rich, no clear relationship between flavonoid load and size or mass emerged. Our analytical data are consistent with field results according to which females rich in UV-absorbing flavonoid wing pigments are more attractive to mate-searching males. In P. icarus, flavonoid richness might therefore increase visibility (by more effective sensory stimulation of the visual system), but could also confer information about the feeding history, and thus ontogenetically determined ‘quality’ of a potential mate.     

CAROTENOIDS OF SIPHONOUS GREEN ALGAE: A CHEMOTAXONOMICAL STUDY

The carotenoid pigments of 50 species of 9 siphonean orders were investigated. The algae of all orders contain the principal carotenoids known from other green algae: α- and β-carotene, lutein, lutein epoxide, violaxanthin, and neoxanthin. Additionally, in some Siphonodadales siphonaxanthin is present, in the Derbesiales, Codiales, and Caulerpales both siphonaxanthin and its ester siphonein are present, whereas in the Dichotomosiphonales only the ester siphonein can be found. The chemotaxonomical value of siphonaxanthin and siphonein is discussed.     

Leaf flavonoid chemistry of Coreopsis (Compositae) section Palmatae

Examination of leaf flavonoids of all taxa ofCoreopsis sectionPalmatae revealed that most members synthesize an array of common flavone (mostly luteolin and apigenin) glycosides. Each diploid species or diploid member of a species is characterized by a particular ensemble of compounds. These taxa includeC. major, C. verticillata, C. pulchra, C. palmata, andC. tripteris. The latter species differs from all other taxa in producing flavonol (kaempferol and quercetin) glycosides and what appear to be 6-oxygenated compounds. Tetraploids ofC. verticillata exhibit the same flavonoids as diploid members of the species, thus flavonoid chemistry supports the hypothesis that they originated from diploids within the species. Certain populations of hexaploid and octoploidC. major are similar chemically to diploids, suggesting they also originated as intraspeciflc polyploids. Other populations of these polyploids exhibit a flavonoid profile which differs from the profile of the diploids, and this profile is nearly identical to the octoploidCoreopsis × delphinifolia. The latter taxon has been viewed by Smith (1976) and Mueller (1974) as an interspecific hybrid betweenC. verticillata andC. major and/orC. tripteris. Species-specific compounds from the former species occur inC. × delphinifolia but no compounds unique to either of the latter two species are discernable. Flavonoid chemistry is not useful in ascertaining whether either or both species have been involved withC. verticillata in producing plants referable toC. × delphinifolia. There is morphological intergradation between octoploidC. major andC. × delphinifolia, and all plants not appearing to be “pure”C. major exhibit a flavonoid chemistry likeC. × delphinifolia. All plants of sectionPalmatae considered to be alloploids (includingC. × delphinifolia) produce the same array of leaf flavonoids, including several “novel” compounds not expressed in the putative parental taxa. Two of the “novel” flavonoids are present in the geographically restricted diploidC. pulchra. The systematic and phylogentic significance of this is not readily apparent.     

Chloroplast pigments and algal systematics

The chloroplast pigments of one typical representative (Pleurochloris magna) and two potential members (clone BSG Sticho and an isolate called Tunis) of the new class Eustigmatophyceae have been examined by modern methods including mass spectrometry. The three cultures all exhibited the same chloroplast pigments: Chlorophyll a, but no b or c, δ-carotene (I), canthaxanthin (II), violaxanthin (IIIa), and esterified vaucheriaxanthin (IVb) plus some free vaucheriaxanthin (IVa). Furanoid rearrangement of the epoxidic carotenoids complicated the analysis. The unique pigment complement hereby indicated for Eustigmatophyceae is clearly different from the pigment distribution patterns reported for Chlorophyceae and Xanthophyceae.     

High light-induced changes in thylakoid supercomplexes organization from cyclic electron transport mutants of Chlamydomonas reinhardtii

The localization of carotenoids and macromolecular organization of thylakoid supercomplexes have not been reported yet in Chlamydomonas reinhardtii WT and cyclic electron transport mutants (pgrl1 and pgr5) under high light. Here, the various pigments, protein composition, and pigment-protein interactions were analyzed from the cells, thylakoids, and sucrose density gradient (SDG) fractions. Also, the supercomplexes of thylakoids were separated from BN-PAGE and SDG. The abundance of light-harvesting complex (LHC) II trimer complexes and pigment-pigment interaction were changed slightly under high light, shown by circular dichroism. However, a drastic change was seen in photosystem (PS)I-LHCI complexes than PSII complexes, especially in pgrl1 and pgr5. The lutein and β-carotene increased under high light in LHCII trimers compared to other supercomplexes, indicating that these pigments protected the LHCII trimers against high light. However, the presence of xanthophylls, lutein, and β-carotene was less in PSI-LHCI, indicating that pigment-protein complexes altered in high light. Even the real-time PCR data shows that the pgr5 mutant does not accumulate zeaxanthin dependent genes under high light, which shows that violaxanthin is not converting into zeaxanthin under high light. Also, the protein data confirms that the LHCSR3 expression is absent in pgr5, however it is presented in LHCII trimer in WT and pgrl1. Interestingly, some of the core proteins were aggregated in pgr5, which led to change in photosynthesis efficiency in high light.     

Relationships in theAcanthaceae and related families as suggested by cladistic analysis ofrbcL nucleotide sequences

A parsimony analysis of DNA sequences of the chloroplast-encoded generbcL from twelve members of theAcanthaceae s.l., including members of the sometimes segregateThunbergioideae andNelsonioideae, and other families in theBignoniales sensuThorne (1992) is presented. The results largely agree with the classification of theAcanthaceae presented byBremekamp (1965) andThorne (1992) and supportNelsonioideae as a sister group to the rest of theAcanthaceae. Thunbergioideae are placed as a sister toAcanthaceae s.str.Acanthus andAphelandra, both representatives ofAcanthoideae, form a sister group toRuellioideae. An analysis of branch support found that many branches throughout theBignoniales are weakly upheld. This points to the need for further studies in the group using more sequences ofrbcL as well as other data. None of the families ofBignoniales as presently circumscribed (includingAcanthaceae s.l.) were strongly supported, although the larger clade containing the families of theBignoniales was robust.     

Leaf flavonoids ofGalium sect.Aparinoides (Rubiaceae)

13 taxa belonging to 4 “species groups” ofGalium L. sect.Aparinoides (Jord.)Gren. produce 15 leaf flavonoids: Apigenin-7-diglucoside, Luteolin-7-monoglucoside and 7-diglucoside, Diosmetin, Diosmetin-7-monoglucoside and 7-diglucoside; Kaempferol-3-rutinoside, Kaempferol-3,7-diglucoside, Quercetin, two Quercetin-3-monoglycosides, Rutin, Quercetin-3-rutinoside-7-glucoside, Quercetin-7-glycoside and an unidentified aglycone. TheG. trifidum, G. obtusum andG. palustre groups (with the exception of theG. tinctorium subspecies andG. elongatum) have similar flavone-flavonole patterns, while theG. antarcticum group produces a specific pattern. Leaf flavonoids of theG. trifidum andG. antarcticum group are inhomogenous, becauseG. tinctorium subsp.tinctorium andG. antarcticum lack flavones. For all taxa (with the exception of those of theG. antarcticum group) intraspecific variation is demonstrated, and 4 populations ofG. trifidum subsp.trifidum, G. tinctorium subsp.tinctorium,G. obtusum subsp.obtusum andG. labradoricum even exhibit intrapopulation variation. The implications of flavonoid data on the systematics and the astonishing intrapopulation and intraspecific variation are discussed.     

Correlations between flavonoid chemistry,anatomy and geography in the restionaceae

Comparisons of the flavonoid patterns in stems and inflorescences between Australasian and South African members of the Restionaceae indicate significant differences with geography. Nine of 14 Australasian species contain gossypetin or a related 8-hydroxyflavonoid and proanthocyanidins are uncommon. By contrast, the 33 South African taxa studied contain common flavonols, flavones and glycoflavones, while proanthocyanidins are present in 29. Two anatomically related South African genera, Chondropetalum and Elegia, contain, in addition, myricetin 3-galactoside, together with the 3-galactosides of the myricetin methyl ethers, larycitrin and syringetin. These results confirm the conclusions derived from anatomy that members of Hypolaena, Leptocarpus and Restio, genera represented in both Australia and South Africa, have the distinctive flavonoids characteristic of their geographic origin rather than of their systematic position. The family as a whole is different in flavonoid pattern from other monocotyledonous families with which it is sometimes associated.     

Distribution and chemotaxonomic significance of flavonoids inAloe (Asphodelaceae)

A chemotaxonomic study of practically all the species of the genusAloe showed that flavonoids occur as major compounds in 31 out of a total of 380 species investigated. Flavanones and dihydroflavonols are present in the exudate of species inAloe ser.Rhodacanthae andSuperpositae and also in a number of the endemic species from Madagascar. Flavones occur as the only major compound in the leaf extracts of the sects.Leptoaloe andGraminialoe. In ser.Macrifoliae and inLomatophyllum, the sister genus ofAloe, isovitexin co-occurred with theC-glucosylanthrone aloin. The chemotaxonomic implication of these results are discussed together with the significance of the taxonomic and chemogeographical distribution of flavonoids inAloe. With a few rare exceptions, the leaf compounds from two different biogenetic pathways (polyketide pathway and flavonoid pathway) are mutually exclusive. Since flavonoids are restricted to the basal groups inAloe, we conclude that flavonoids are plesiomorphic characters inAloe reflecting ancient phylogenetic and biogeographic links.     

Pigment analysis of chloroplast pigment-protein complexes in wheat

Pigment-protein complexes separated from wheat (Triticum aestivum L. selection ND96-25 by two gel electrophoresis techniques were analyzed by high-performance liquid chromatography for chlorophylls and carotenoids. The two techniques are compared, and pigment analyses are given for the major reaction centers and light-harvesting complexes. Reaction centers contain mostly chlorophyll a, carotene, and lutein, whereas light-harvesting complexes contain chlorophyll a, chlorophyll b, lutein, and neoxanthin. The amounts of violaxanthin are variable.     

Potentilla basaltica (Rosaceae), a new species from Nevada

Potentilla basaltica Tiehm & Ertter is described, illustrated and compared to other members of theMultijugae group,P. newberryi, andIvesia. The leaf form and small flowers are reminiscent ofIvesia, indicating a possible new link between the two genera.     

CHROMOSOMAL ANALYSES AND THE ORIGIN OF ALLOPOLYPLOID POLYPODIUM VIRGINIANUM (POLYPODIACEAE)

Polypodium virginianum L. has been treated as a morphologically and chromosomally variable species. Recently, however, two species have been named from within the P. virginianum complex. Chromosome counts reported here confirmed that these segregate species, P. appalachianum Haufler and Windham and P. sibiricum Siplivinskij, are diploids with n = 37. It was further hypothesized that hybridization between these diploids initiated the allotetraploid P. virginianum. Naturally occurring, sterile triploid plants obtained from habitats in which the putative allotetraploid was sympatric with its presumed diploid progenitors have been verified isozymically as backcross hybrids. Meiotic chromosomal behavior showed that the triploids contained univalents and bivalents in nearly equal numbers, confirming that tetraploid P. virginianum contained one genome from each diploid. Observation of three to six trivalents in triploid preparations suggested that the diploids are still closely related genetically. This hypothesis was supported by isozymic studies which found a genetic identity of 0.610 between P. appalachianum and P. sibiricum, a value much higher than the average identity for congeneric fern species studied to date (0.33) and higher than any other species pair in the P. vulgare L. complex (average I = 0.307). These chromosomal and isozymic data help to resolve a biosystematic riddle that has interested pteridologists for over 40 years.     

Chemosystematics ofSuillaceae andGomphidiaceae (suborderSuillineae)

The chemotaxonomic findings relating to the generaBoletinus, Suillus, Gastroboletus, Gomphidius, andChroogomphus are summarized and discussed, using published data as well as our own hitherto unpublished evidence of pigments and chromogens. The study confirms repeatedly made claims that these genera are closely related. In addition to the presence of pigments which are typical for most members of theBoletales (e.g., pulvinic acid derivatives, terphenyl quinones, cyclopentenones), prenylated phenols and quinones can also be constantly detected here (with the exception ofBoletinus), just as inRhizopogon. Accordingly,Suillus is more closely related to theGomphidiaceae andRhizopogonaceae than to the remaining boletes. It is therefore necessary to establish a new family (Suillaceae which includeBoletinus, Suillus, andGastrosuillus) and a new suborder (Suillineae which includeSuillaceae, Gomphidiaceae, andRhizopogonaceae) within theBoletales. Chemosystematics ofBoletales 2. For part 1 seeBesl & al. (1986). Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday     

Flavonoids of some species of Chrysosplenium

The flavonoid chemistry of eight species of Chrysosplenium has been established. The species studied were C. americanum, C. echinus, C. flagelliferum, C. glechomaefolium, C. iowense, C. rosendahlii, C. wrightii and C. valdivicum. The major compounds present were O-methylated flavones having an extra hydroxyl group at positions 6 and/or 2′ except for C. valdivicum which has isorhamnetin as its major flavonoid and only a trace of a compound bearing an extra hydroxyl group. Distribution of the O-methylated compounds in the genus correlates well with Franchet's sectional view of the genus wherein he recognized alternate-leaved vs opposite-leaved groups. The flavonoids of C. valdivicum represent a link between the more advanced members of the genus and other genera of the Saxifragaceae.     

Effects of therolABC,rolAB, and CaMV 35S-rolC genes on growth and nitrogen fixation inLotus corniculatus L.

Lotus corniculatus has been transformed byAgrobacterium tumefaciens harbouring therolABC, rolAB, and 35S-rolC constructs. Growth, shoot and root morphology, cytokinin and auxin concentrations in the shoots, chlorophyll content in the leaves, nodulation and nodule nitrogenase activity of clonal progenies of selected transformants, in which the transferredrol sequences were proved, were compared with control plants. The most striking alterations were observed in the 35S-rolC transformants (dwarfism, shoot and root branching, shorter internodes, delayed nodule formation, decreased nitrogenase activity, reduced content of leaf pigments) in comparison with either therolAB, rolABC, or controls. TherolAB androlABC transformants were very similar to the control plants in their morphology as well as in most other traits measured.     

Flavonoid chemistry of the endemic species of Myrceugenia (Myrtaceae) of the Juan Fernandez Islands and relatives in continental South America

Twenty-one flavonoids were isolated from the leaves of two endemic species ofMyrceugenia on the Juan Fernandez Islands,M. fernandeziana andM. schulzei, from two related species from Brazil,M. campestris andM. rufescens, and from five species from continental Chile,M. colchaguensis, M. exsucca, M. lanceolata, M. pinifolia, andM. rufa. A phenetic analysis was used to evaluate chemical similarities.Myrceugenia campestris andM. rufescens appear most closely related to each other based on flavonoid profiles, and they are also different from the other seven species. The two endemic species in the Juan Fernandez Islands,M. fernandeziana andM. schulzei, group with the continental Chilean species. The former is most closely related toM. lanceolata, and the latter clusters withM. exsucca, although somewhat distantly. The results suggest that the two Juan Fernandez endemics are derived from two introductions from the Chilean continent and not from immigrants from the eastern side of the Andes.