Chromosome numbers and DNA?C values in the genus Lippia (Verbenaceae)

The genus Lippia comprises herbs, shrubs, and small trees, including many species with medicinal properties. The species are distributed throughout South and Central America and Tropical Africa, but the majority of them occur in Brazil, Paraguay, and Argentina. The DNA?C value of 28 Brazilian species has been estimated by flow cytometry. Estimated DNA?C values ranged from 0.825?pg (L. corymbosa) to 2.150?pg (L.?brasiliensis). In addition, new chromosome numbers of 12 species have also been described, and meiotic cells with 12, 13, and 14 chromosome pairs were observed. A straightforward correlation between chromosome number and DNA?C value was not observed, probably due to two outlier species of Lippia that have been transferred from the genus Lantana. In general, the data confirm previous reports regarding the variation within the taxonomic sections and also suggest a new revision in section Zapania. Aspects of karyotypic evolution of the genus are also discussed.     

Study of pollen brush in selected species of Astragalus L. subgenus Pogonophace Bunge (Leguminosae)

Nine species of Lippia (Verbenaceae) were studied by RAPD markers in order to evaluate the degree of genetic diversity. The following species were collected at the Cadeia do Espinhaço Mountains, Southeast Brazil: L. corymbosa, L. diamantinensis, L. filifolia, L. florida, L. hermannioides, L. lupulina, L. rotundifolia, L. rosella and L. sidoides. The analysis was performed using 18 primers that generated 490 fragments and only one primer was found to be monomorphic in all individuals. The average interspecific genetic distances were similar for all species and higher than the intraspecific genetic distances. Species with narrow occurrence did not show low intraspecific diversity. The molecular data were used to generate an UPGMA dendrogram that showed two major groups with a clear distribution among the species. RAPD analysis was efficient to address the genetic diversity of Lippia species and contributed to understand the adaptation to the environment, conservation and taxonomic implications.     

Phenylethanoid glycosides from Lippia javanica

Lippia javanica (N.L.Burm.) Spreng. is an aromatic, multipurpose medicinal plant from which a number of volatile compounds have been identified, together with toxic triterpenoids and iridoid glycosides. Two additional phenylethanoid glycosides, verbascoside and isoverbascoside, were isolated from L. javanica and characterized. High performance liquid chromatography analyses of polar extracts of three other Lippia species (L. scaberrima, L. rehmannii and L. wilmsii), indigenous to South Africa, revealed the presence of both isomers. When compared to the other indigenous Lippia species, the leaves of L. javanica were found to contain the highest concentrations of both isomers. In addition, the intraspecies variation of the verbascoside/isoverbascoside content of L. javanica, harvested from the same and different localities, was investigated. The concentrations of the two phenylethanoids remained fairly consistent within and between different populations, even when geographically separated. While these compounds are produced by many genera, they may now be added to the list of iridoid glucosides employed as chemotaxonomic markers for Lippia species.     

CHROMOSOME NUMBERS IN CUPHEA (LYTHRACEAE): NEW COUNTS AND A SUMMARY

The American genus Cuphea with ca. 260 species is extremely diverse with respect to chromosome number. Counts are now available for 78 species and/or varieties, or 29% of the genus. Included in this study are first reports for 15 taxa from Brazil, Cuba, Dominican Republic, Mexico, and Venezuela. Twenty-two different numbers are known for the genus, ranging from n = 6 to n = 54. The most common number in the primary center of species diversity in Brazil is n = 8, which is regarded as the base number of the genus. Two numbers are most common in the secondary center in Mexico, n = 10 and n = 12. Species with n = 14 or higher are considered to be of polyploid origin. Polyploids comprise 46% of the total species counted and appear in 9 of the 11 sections for which chromosome numbers have been reported. Aneuploid species comprise ca. 25% of the genus and are known from 7 of the 11 sections. The two subgenera are not characterized by different chromosome numbers or sequences of numbers. None of the 14 sections are circumscribed by a single chromosome number. Morphological and ecological variability in widespread, weedy species is correlated with differing chromosome numbers in some species whereas in others the chromosome number is stable. Summary of chromosome numbers by taxonomic section is presented. Section Euandra, centered in eastern Brazil, and the largest section of the genus, appears to be chromosomally most diverse. In section Trispermum, characterized by difficult, variable species with intermediate forms, two of the four species studied have polyploid races. Section Heterodon, endemic to Mexico and Central America and comprising most of the annual species of the genus, is best known chromosomally. Chromosome numbers have been counted for 25 of 28 species, and 12 different numbers are reported. The most advanced sections, Melvilla and Diploptychia, with numerous species occurring at higher altitudes, are characterized by high polyploids. Apomictic species occur in sect. Diploptycia. The cytoevolution of Cuphea is complex with frequent polyploid and aneuploid events apparently playing a significant role in speciation in both centers of diversity.     

A chemotaxonomic assessment of four indigenous South African Lippia species using GC–MS and vibrational spectroscopy of the essential oils

Lippia species are widely used as traditional remedies by many South African communities. The identification of Lippia spp. indigenous to South Africa is currently based on the morphology and geographical origin of the specimen. However, morphological similarities are evident and due to sympatric distributions, different species may co-occur in the same natural environment, thereby presenting difficulties in the taxonomic delimitation of these taxa. In this paper, gas chromatography–mass spectrometry (GC–MS) and vibrational spectroscopic analyses were used to investigate the chemotaxonomic differentiation of four Lippia species (L. javanica, L. scaberrima, L. rehmannii and L. wilmsii), based on the essential oil composition. The results demonstrate that multivariate classification of chromatographic data enabled separation of Lippia oils into three distinct clusters representing L. scaberrima, L. rehmannii and L. javanica. With the aid of chemometric algorithms, it was also possible to use both mid infrared (MIR) and near infrared (NIR) spectroscopy for a clear distinction of the Lippia spp., with results comparable to those obtained by GC–MS. Orthogonal projections to latent structures (OPLS) presented a better classification algorithm than principal component analysis (PCA), in both GC–MS and spectroscopy analyses. Chemical variations within the Lippia spp. complex were evident, particularly for L. javanica and L. scaberrima, which exhibited significant intra-species variation.     

South African Lippia herbal infusions: Total phenolic content,antioxidant and antibacterial activities

Lippia javanica and Lippia scaberrima are used as herbal remedies and are commercially traded as health teas in southern Africa under the brands “Mosukujane” and “Musukudu”, respectively. This study evaluates the relationship between the presence of phenolic compounds and the antioxidant activities of infusions prepared from four Lippia species (L. javanica, L. scaberrima, L. rehmannii and L. wilmsii) indigenous to South Africa. The antioxidant activities of the infusions, determined by the 2,2-diphenylpycrylhydrazyl (DPPH) method, were also compared to those of popular black, green and herbal tea brands. Of the four indigenous species, infusions of L. javanica and L. wilmsii exhibited the highest antioxidant activities (EC₅₀: 358 and 525 µg/ml, respectively) and contained the most phenolic compounds (14.8 and 14.5 mg/ml of dry weight gallic acid equivalent, respectively). Antibacterial activities of methanolic extracts of the four Lippia species were determined against four human pathogens (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa). The extract of L. javanica was the most active against all the pathogens tested. Those Lippia species (L. javanica and L. wilmsii) previously reported to produce higher levels of the pharmacologically active phenylethanoid glycosides verbascoside and isoverbascoside, portrayed stronger antioxidant and antibacterial activities. This study gives credence to the use of infusions of these Lippia species for their general health benefits.     

Chromosome counts in the genusAlchemilla (Rosaceae) from SW Europe

This paper presents the results of a karyological analysis of 14 species ofAlchemilla L. collected from SW Europe (Spain and French Pyrenees). About 75% of the analyzed species have chromosome numbers 2n = 95–136. A few species have lower chromosome numbers. The chromosome numbers of 13 species are presented for the first time.     

半蒴苣苔属植物染色体制片优化及染色体数目和倍性研究

染色体数目和倍性是系统与进化生物学和遗传学研究中十分重要的基础信息。为探索半蒴苣苔属染色体制片的适宜条件以及染色体数目的进化模式及其与物种的进化关系，该研究基于半蒴苣苔属染色体数目的进化历史，并根据该属植物具有叶片扦插繁殖的特性，采用叶片水培生根法获取半蒴苣苔(Hemiboea subcapitata)、弄岗半蒴苣苔(H.longgangensis)、龙州半蒴苣苔(H.longzhouensis)、江西半蒴苣苔(H.subacaulis var.jiangxiensis)、华南半蒴苣苔(H.follicularis)和永福半蒴苣苔(H.yongfuensis)6种植物的根尖材料，分析不同实验条件对染色体制片效果的影响，对染色体制片实验的条件进行优化及染色体计数，结果表明：(1)9:30—10:00取材，解离10 min以及染色15 min为半蒴苣苔属染色体制片的适宜条件。(2)上述6种半蒴苣苔属植物均为二倍体，染色体数目均为32(2n=2x=32)。(3)除个别物种染色体数目有变化以外，该属大部分物种染色体数目可能为2n=2x=32且染色体数目变化可能是非整倍化的作用，与物种进化没有明...     

Karyological features and banding patterns in Arachis species belonging to the Heteranthae section

The section Heteranthae of Arachis is endemic to Brazil, occurring mainly in the semi-arid northeastern region. The section is considered derived within the genus and includes only annual herbs. Most previous cytological evaluations were restricted to chromosome numbers and morphology. The present approach comprised karyomorphological evaluation in 10 accessions from five species of this section, including standard staining and fluorochrome banding [chromomycin A3 (CMA)/4′,6-diamidino-2-phenylindole (DAPI)]. All accessions presented diploid chromosome numbers (2n = 20) with a prevalence of metacentric to submetacentric chromosome morphology. Arachis dardani, Arachis pusilla, and Arachis interrupta presented karyotypic formula 18m + 4sm and satellite type 2, while Arachis sylvestris and Arachis giacomettii presented 16m + 4sm and satellite type 10. Despite the conserved morphological features, higher diversity was detected in terms of size and number of GC-rich (CMA⁺) heterochromatic blocks among the species; however, all of them were located in the pericentromeric regions. The species A. pusilla presented the highest number of GC-rich blocks, present in all chromosomes of the complement. Based on the data obtained and considering literature data, we suggest that A. dardani and A. interrupta occupy a basal position in the group due to their moderate asymmetry and satellite type. At least in A. pusilla, the constitutive heterochromatin seems to have suffered recent modifications of its constitution, in contrast to other species that present pericentromeric CMA⁺ blocks in all chromosomes. A. giacomettii and A. sylvestris are closely related to each other and also similar to the previously studied Arachis seridoensis, revealing two clear-cut subgroups within the section from the karyological point of view.     

Étude cytotaxinomique de quelquesDipsacaceae d'Iran

Chromosome numbers for 28 Iranian populations ofDipsacaceae, corresponding to 14 taxa, are presented. New are those forScabiosa aff.olivieri var.pinnatisecta, S. persica, Pterocephalus canus, P. kurdicus, Dipsacus strigosus, Cephalaria dichaetophora, C. hirsuta, C. microcephala, C. subindivisa andC. aff.sublanata. Except forC. syriaca (x = 5) andC. dichaetophora (x = 7 : new basic chromosome number forCephalaria), all species examined are characterized by the basic chromosome number (x = 9). Instances of aneusomaty, B-chromosomes, aneuploidy, dysploidy, and polyploidy have also been found.

     

Biology and host range of Ophiomyia camarae, a biological control agent for Lantana camara in South Africa

The herringbone leaf-mining fly, Ophiomyiacamarae Spencer, is a promising candidateagent for the biological control of the alieninvasive weed Lantana camara L. in SouthAfrica. During extensive host-specificity testsinvolving 39 test plant species from 12families, survival to adulthood was restrictedto L. camara, L. trifolia, and fourspecies of the closely-related genus Lippia (Verbenaceae) in no-choice tests. However, survival of the immature stages wassignificantly lower on L. trifolia andthe four Lippia species than on L.camara. In addition, O. camaraedisplayed very strong oviposition preferencefor L. camara during paired-choice tests.This narrow laboratory host range suggests thatO. camarae will not pose any risks tonon-target verbenaceous plants if released inSouth Africa. Permission to release O. camaraeinto South Africa was approved by the regulatoryauthorities in 2001.     

Chromosome Numbers and Karyotypes of Species of Vernonia sect. Lepidaploa (Asteraceae: Vernonieae)

Vernonia is the largest genus of the tribe Vernonieae (Asteraceae) and comprises more than 1,000 species. In the present study we explore chromosome number and karyotype variation of eight species treated within different subsections of the section Vernonia sect. Lepidaploa. We aimed to explore if these data support the recognition of a single large genus (sensu Baker) or favor its splitting into 22 small genera (sensu Robinson). The species were collected in ??cerrado??, rupicolous and disturbed areas in the states of S?o Paulo and Minas Gerais, Brazil. Chromosome numbers varied from 2n?=?32 to 60. Most chromosomes were small, and the karyotype analysis revealed a predominance of metacentric and some submetacentric chromosomes. The karyotype symmetry in Vernonia was moderate (TF% 32.2 to 45.9), with the most symmetrical karyotype observed in V. rubriramea. The results obtained here did not conclusively support any of the taxonomic proposals for Vernonia due to the absence of distinctive or characteristic karyotype patterns for any of the taxonomic groupings, i.e., sections and subsections (sensu Baker) or new genera (sensu Robinson). Nevertheless, a tenuous relationship was observed between the chromosome numbers reported in the literature, those recorded here, and the taxonomic alterations suggested by Robinson for the genera Lessingianthus, Chrysolaena, and Vernonanthura that were originally part of Vernonia sensu Baker.     

Chromosomal analysis of Leptinotarsa and Labidomera species (Coleoptera: Chrysomelidae)

Chromosomes were examined from 13 Leptinotarsa species: L. decemlineata, L. texana, L. defecta, L. juncta, L. rubiginosa, L. haldemani, L. tumamoca, L. peninsularis, L. behrensi, L. heydeni, L. lineolata, L. typographica, and L. undecimlineata. With the exception of L. undecimlineata, which has 2n=32+XO, all other species have the basic chromosome number 2n=34+XO. Of two Labidomera species also examined, L. clivicollis has 2n=32+XO and L. suturella has 2n=30+XO. Idiograms showed that the majority of the autosomes are submetacentric. All species have a large submetacentric X chromosome. Meiotic pairings were regular with both closed and open bivalents. Chiasma frequencies varied considerably among species and even between populations. No distinct correlation was evident when chromosome numbers and chiasma frequencies were compared with host plant association and geographic distribution patterns of Leptinotarsa species.     

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.     

Chromosome numbers of Panamanian Lecythidaceae and their use in subfamilial classification

Nine species of Lecythidaceae subfamily Lecythidoideae in four genera whose chromosome numbers were previously unknown, have 17 as their basic chromosome number:Eschweilera pittieri, three other unidentified species ofEschweilera, Grias cauliflora, Gustavia dubia, G. superba, Lecythis minor, andL. tuyrana. All are diploid exceptGustavia superba, which is tetraploid.Couroupita guianensis, which was previously—and probably incorrectly—reported to have a gametic chromosome number of 18, also hasn = 17. The known chromosome numbers support recognizing at least three of Niedenzu’s subfamilies: Planchonioideae withx = 13, Napoleonaeoideae withx = 16, and Lecythidoideae withx = 17. His fourth subfamily, Foetidioideae, with one genus of five species, has not been counted. Cytological data have been and probably will be useful in indicating to what subfamily problematic genera belong and in showing interesting phytogeographic patterns within the family. On the other hand, cytological data provide no recognizable clues relating the Lecythidaceae to other families.     

Additional chromosome numbers inPelargonium (Geraniaceae)

Mitotic chromosome counts were made from field collected and subsequently cultivated plants of 61Pelargonium species from 14 sections. The 33 new results are presented. 47 of the species have a basic number of x = 11, nine spp. of x = 9 and five spp. of x = 8. 17 spp. are polyploid. In two sections species with different basic numbers occur, which is of interest for the subgeneric classification. The size of the chromosomes varies between the investigated species. Most but not all species with x = 11 have short, those with x = 8, 9 large, and only exceptionally short chromosomes. Within sections chromosome size is not always uniform. The relationship between the different basic chromosome numbers is discussed.     

Four new Brazilian species of Lonchocarpus (Leguminosae, Papilionoideae, Millettieae)

Lonchocarpus castaneifolius, L. grazielae, L. longiunguiculatus, and L. montanus from Brazil are described and illustrated based on field and herbarium studies. The first species belongs to Lonchocarpus sect. Punctati and is restricted to northeastern Brazil (Bahia state). The other three are included in sect. Laxiflori. Lonchocarpus grazielae is restricted to the southern coastal region (Santa Catarina state), L. montanus is found in northeastern Brazil (Bahia and Piauí states), the west-central region (Goiás and Tocantins states) and the southeast (Minas Gerais state), and L. longiunguiculatus occurs in northeastern (Bahia state) and southeastern (Minas Gerais state) Brazil.     

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.     

Karyological features and cytotaxonomy of the tribe Vernonieae (Asteraceae)

Chromosome numbers are reported for 29 populations of 19 Vernonieae taxa collected mainly in the northeastern region of Brazil. Among them, data for five genera (Blanchetia, Rolandra, Pithecoseris, Stilpnopappus and Vanillosmopsis) are here reported for the first time, and the first chromosome counts are presented for 12 species. Chromosome numbers are quite diverse among and sometimes within genera, especially in the controversial and large subtribe Vernoniinae. The numbers varied from 2n = 18 to 2n = ~72. The main karyoevolutionary mechanism seems to be dysploidy, while polyploidy is probably associated with ancient hybridization processes generating most paleotetraploid genera. All studied species presented semi-reticulated interphase nuclei and proximal-early condensing behavior in prophase to prometaphase. In one species (Vernonia condensata with 2n = 40) fluorochrome staining with CMA/DAPI revealed five chromosome pairs bearing subterminal CMA⁺/DAPI^? heterochromatin, probably NOR-associated, revealing the existence of low amounts of satellite DNA. The role of these features in the evolution of the tribe is discussed, revealing some interesting aspects for understanding of the Vernonieae karyoevolution, especially regarding neotropical members.