CHROMOSOME NUMBERS IN CHIHUAHUAN DESERT CACTACEAE. TRANS-PECOS TEXAS

Chromosome numbers are presented for 100 collections of Cactaceae from the Trans-Pecos region of Texas. A total of 65 taxa representing 52 species and 12 genera were counted, including first reports for 45 taxa and new ploidy levels for four taxa. Notable among those listed are counts for Opuntia schottii var. grahamii (n = 11, ca. 22), O. stanlyi (n = 22), O. arenaria (n = 11), O. phaeacantha var. spinosibacca (n = 22), O. lindheimeri var. lindheimeri (n = 11), O. strigil (n = 11), Echinocereus enneacanthus var. cf. dubius (n = ca. 22), E. pectinatus var. neomexicanus (n = 22), and Thelocactus bicolor var. bicolor (n = 22). Endomitosis was found to be present in O. phaeacantha var. spinosibacca, Mammillaria pottsii, and Neolloydia intertexta var. dasyacantha. Meiotic irregularities were noted in some species belonging to the genera Opuntia and Echinocereus. Phytogeographic considerations are inferred from the chromosomal data for O. polyacantha, O. lindheimeri, and O. ficusindica. A base number of x = 11 in Cactaceae is supported.     

BIOSYSTEMATIC STUDIES IN THE BOUTELOUA CURTIPENDULA COMPLEX. V. MEGASPOROGENESIS AND EMBRYO SAC DEVELOPMENT

Megasporogenesis and embryo sac development in the sexually reproducing taxa Bouteloua warnockii (2n = 22), B. media (2n = 20), B. uniflora Vasey var. uniflora (2n = 20), B. uniflora var. coahuilensis Gould and Kapadia (2n = 20), and B. curtipendula var. curlipendula (2n = 40) all were found to be of the Adoxa type, in which all 4 megaspores persist and divide once to form an 8-nucleate embryo sac. On the other hand, evidence indicated that plants of B. curtipendula var. caespitosa with high ancuploid chromosome numbers reproduce by pseudogamous fertilization of an aposporous embryo sac. In this taxon the megaspore mother cell did not go beyond the first anaphase of meiosis and the functional embryo sac developed from a nucellar cell. Although the 8-nucleate embryo sac was typical, a 3-nucleate embryo sac was observed to develop in some cases.     

Anti-diabetic properties of three common Bidens pilosa variants in Taiwan

Bidens pilosa L. var. radiata (BPR), B. pilosa L. var. pilosa (BPP), and B. pilosa L. var. minor (BPM) are common variants of a plant often used as a folk remedy for diabetes in Taiwan. However, the three variants are often misidentified and little is known about their relative anti-diabetic efficacy and chemical composition. In this paper, we have first developed a method based on GC–MS and cluster analysis with visualization to assist in rapidly determining the taxonomy of these three Bidens variants. GC–MS was used to determine the chemical compositions of supercritical extracts, and differences and similarities in the variants were determined by hierarchical cluster analysis. Next, the HPLC profiles of the methanol crude extracts in the Bidens plants and evaluated anti-diabetic effects of methanol crude extracts were compared, as well as three polyacetylenic compounds of the Bidens plants using db/db mice. Single-dose and long-term experiments showed that the BPR extract had higher glucose-lowering and insulin-releasing activities than extracts from the other two variants, and that cytopiloyne was the most effective pure compound among the three polyacetylenic compounds. BPR extract and cytopiloyne also significantly reduced the percentage of the glycosylated hemoglobin A1c in db/db mice. Besides, both animal studies and HPLC analysis demonstrated a good correlation between anti-diabetic efficacy of the Bidens extracts and the particular polyacetylenes present.     

Effects of co-cropping Bidens pilosa (L.) and Tagetes minuta (L.) on bioaccumulation of Pb in Lactuca sativa (L.) growing in polluted agricultural soils

Polluted agricultural soils are a serious problem for food safety, with phytoremediation being the most favorable alternative from the environmental perspective. However, this methodology is generally time-consuming and requires the cessation of agriculture. Therefore, the purpose of this study was to evaluate two potential phytoextractor plants (the native species Bidens pilosa and Tagetes minuta) co-cropped with lettuce growing on agricultural lead-polluted soils. The concentrations of Pb, as well as of other metals, were investigated in the phytoextractors, crop species, and in soils, with the potential risk to the health of consumers being estimated. The soil parameters pH, EC, organic matter percentage and bioavailable lead showed a direct relationship with the accumulation of Pb in roots. In addition, the concentration of Pb in roots of native species was closely related to Fe (B. pilosa, r = 0.81; T. minuta r = 0.75), Cu (T. minuta, r = 0.93), Mn (B. pilosa, r = 0.89) and Zn (B. pilosa, r = 0.91; T. minuta, r = 0.91). Our results indicate that the interaction between rhizospheres increased the phytoextraction of lead, which was accompanied by an increase in the biomass of the phytoextractor species. However, the consumption of lettuce still revealed a toxicological risk from Pb in all treatments.     

Low Allozymic Variation in the Bidens pilosa L. Complex (Asteraceae)

Bidens alba, B. subalternans, and B. pilosa form a complex group based on their morphological similarities. Bidens pilosa L. and B. subalternans DC. are herbs with a wide distribution in agricultural and disturbed areas. Bidens alba (L.) DC. varies in size from herb to subshrub and has a coastal distribution. Enzyme electrophoresis was used to evaluate genetic diversity in 12 populations of Bidens. All but three loci (Lap-1, Est, and Got) were monomorphic. Est-1 and Got were polymorphic only in B. alba. Lap-1 was polymorphic only in B. pilosa and B. subalternans. The estimates of genetic variability were low for all three taxa and all of the populations studied. Genetic diversity varied from 0.01 to 0.03. Mean genetic identities were high among populations of each species (0.99 for B. alba and 1.00 for B. pilosa and B. subalternans) and among the three species (1.00). Bidens pilosa and B. subalternans could be considered a single species if the taxonomy of the group were based solely on isozyme data.     

CHROMOSOME NUMBERS IN MEXICAN ASTERACEAE

Chromosome numbers are reported for 100 collections distributed among 68 species and 46 genera of Mexican Asteraceae. Included are systematic discussions regarding chromosome numbers of the following taxa: Haplopappus spinulosus var. scabrellus (n = 4, 8); Hofmeisteria fasciculata (n = 19), Malperia tenuis (n = 10), and Pleurocoronis laphamioides (n = 9); Cymophora pringlei (2n = 16); Plummera (n = 15); and Porophyllum tridentatum var. crassifolium (n = 15) as related to Chrysactinia and Nicolletia.     

BIOSYSTEMATIC STUDIES IN THE BOUTELOUA CURTIPENDULA COMPLEX. III. POLLEN SIZE AS RELATED TO CHROMOSOME NUMBERS

Pollen size statistics are presented for 10 closely related species of Bouteloua and relationships between pollen size and chromosome numbers are presented for 13 populations of 5 species and 3 varieties. With 1 exception, all populations of all taxa conformed to a general pattern of pollen size dependent upon chromosome number. Chromosome numbers varied from 2n = 20 to 2n = ca. 103, with several independent aneuploid series. Statistical analyses were made of pollen size as related to chromosome number in the 3 varieties of B. curtipendula. These data showed that tetraploids (2n = 40) of var. tenuis had significantly greater pollen size and coefficient of variation than diploids (2n = 20) of the same variety. Similarly, aneuploids of var. curtipendula with 2n = 45 to 2n = 64 chromosomes had significantly larger and more variable pollen than tetraploids (2n = 40) of the same variety. Highly significant positive regression coefficients were obtained from analyses of chromosome numbers and mean pollen size, and chromosome numbers and coefficient of variation, for var. curtipendula. Regression coefficients for var. caespitosa populations with chromosome numbers over the hexaploid (2n = 60) level were not significant.     

月季种质资源的倍性变异及核型多样性研究(英文)

采用常规压片法对包括5个蔷薇野生种、8个古老月季及9个现代月季品种共22份月季种质资源进行核型分析。供试材料共有3种不同倍性:5个野生种中粉团蔷薇为三倍体(2n=3x=21),其他4个材料为二倍体(2n=2x=14);9个现代月季品种均为四倍体(2n=4x=28);而古老月季品种中包含二、三、四倍体3种倍性。22份材料中共发现4种不同类型的核型,在野生种中为1A、2A;古老月季中为1A、2A、1B;现代月季中为1A、1B、2B。另外,供试材料在核不对称系数、着丝粒指数、随体数目及位置、染色体相对长度组成等方面差异较大,说明在月季种质资源中存在着丰富的核型多样性。     

Karyology of Aconitum subgenus Lycoctonum (Ranunculaceae) from China,with a report of the new base chromosome number x = 6 in the genus Aconitum

In order to gain better knowledge of the number and morphology of chromosomes in Aconitum subgen. Lycoctonum in China, 60 populations belonging to 20 species were cytologically studied. Chromosome numbers of six species (A. apetalum, A. finetianum, A. fletcheranum, A. longecassidatum, A. umbrosum and A. wangyedianense) are here reported for the first time. One species, A. fletcheranum, has 2n = 12, and thus is a diploid based on x = 6, a new base chromosome number for the genus Aconitum. Most of the remaining taxa are diploid (2n = 16) based on x = 8, but five taxa (A. angustius, A. brevicalcaratum var. brevicalcaratum, A. brevicalcaratum var. parviflorum, A.chrysotrichum and A. crassiflorum) are tetraploid with 2n = 32, and one species (A. apetalum) is hexaploid with 2n = 48, the highest ploidy level currently known in the subgenus. Disregarding differences in the presence or absence and number of satellites, the karyotypes of all the 2n = 16 species are quite uniform (2n = 2m + 6sm + 8st), but A. novoluridum, the only species of A. section Alatospermum, has an intrachromosomally less asymmetric karyotype (2n = 2m + 14sm), which lends further support for the primitive condition of its section as inferred from gross‐morphology. Chromosomal variation in the subgenus and the relationships of some of the species are discussed.     

A karyosystematic study of the genus Bellevalia Lapeyr. (Hyacinthaceae) in Greece

The genus Bellevalia is represented in Greece by eight taxa, three of which are endemic. Bellevalia brevipedicellata (2n = 8) and B. sitiaca (2n = 16) are restricted to the island of Kriti, while B. hyacinthoides (2n = 8, 12) is distributed in the Kiklades Islands, the central and southern mainland and the Ionian Islands. Four taxa, i.e. B. dubia subsp. boissieri (2n = 8), B. trifoliata (2n = 8), B. romana (2n = 8) and B. ciliata (2n = 8, 16) are Mediterranean elements. The presence of B. edirnensis (2n = 24) is reported as new for the Greek flora. New ploidy levels of three Bellevalia species (triplo‐, tetra‐ and hexaploids) are reported for the first time. The main morphological features, the chromosome numbers, the karyotype morphology, as well as the geographical distribution and further issues of taxonomy and conservation of all Bellevalia taxa in Greece are presented and discussed. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 723–739.     

百合科两个分类群学名的订正

笔者在编研《中国生物物种名录》第1卷第3分册(百合科——五桠果科)的过程中,发现百合科两个物种在《中国植物志》和Flora of China中均使用了错误的名称,需要做出新处理。其中,有斑百合的正确名称应为Lilium concolor var.pulchellum(Fisch.)Baker,而非《中国植物志》使用的晚出等名Lilium concolor var.pulchellum(Fisch.)Regel,黄花油点草的正确名称应为Tricyrtis maculata(D.Don)J.F.Macbr.,而非Flora of China使用的Tricyrtis pilosa Wall.。     

CYTO-TAXONOMIC NOTES ON BUDDLEIA

Moore R. J. (Can. Dept. Agric, Plant Res. Inst., Ottawa, Ont.) Cyto-taxonomic notes on Buddleia. Amer. Jour. Bot. 47(6): 511–517. 1960.—Chromosome numbers of 29 taxa of Buddleia are reported; those of the following species are reported for the first time: B. crispa 2n=38, B. delavayi 2n=ca. 114, B. grandiflora 2n=38, B. nivea var. yunnanensis 2n=ca. 228, B. paniculata 2n=38, B. pterocaulis, 2n=ca. 228, and the artificial hybrids B. globosa × B. davidii 2n=76, B. caryopteridifolia × B. alternifolia 2n=38, Nicodemia madagascariensis × B. asiatica 2n=38. Notes on the taxonomy and nomenclature of the species are included. The evolution of the Buddleia inflorescence is briefly discussed and some natural species groups within the Asiatic species are suggested.     

Effects of irradiance and spectral quality on seedling development of two Southeast Asian Hopea species

 Seedling developmental responses to understory shade combine the effects of reductions in irradiance and changes in spectral quality. We studied the seedling development of two Southeast Asian dipterocarp trees in response to differences in irradiance (photosynthetic photon flux density, PPFD) and spectral quality (red to far-red ratio, R:FR). The two species, Hopea helferei and H. odorata, are taxonomically closely related but differ in their ecological requirements; H. helferei is more drought-tolerant and typically grows in more open habitats. Seedlings were grown in six different replicated shadehouse treatments varying in percentage of solar PPFD and R:FR. The two species differed in the influence of light variables on most seedling characters, particularly for final height, internode distance, branch/trunk internodes, stem length/mass, leaf area/stem length, petiole length, and growth/mol of photons received. Most of the characters in both taxa were primarily influenced by PPFD, but spectral quality also influenced some characters – more so for H. odorata. The latter species grew more rapidly, particularly in the low PPFD treatments, and its leaves were capable of higher photosynthesis rates. However, growth in H. helferei was not reduced in direct sunlight. The growth of this taxon may be constrained by adaptations, particularly in leaves, for drought tolerance. Received: 14 April 1996 / Accepted: 8 October 1996     

BIOSYSTEMATICS OF THE BOTHRIOCHLOA BARBINODIS COMPLEX (GRAMINEAE)

The New World species of Bothriochloa O. Kuntze are polyploids with 2n = 60, 120, 180 and 220 chromosomes and they reproduce sexually. Plants with 2n = 180 chromosomes constitute the extremely variable B. barbinodis (Lag.) Herter, which is subdivided into var. barbinodis, var. palmeri (Hack.) de Wet comb. nov., and var. schlumbergeri (Fourn.) de Wet comb. nov. The single collection with 2n = 220 chromosomes belongs with var. schlumbergeri. Plants resembling B. barbinodis in inflorescence structure but having well-developed pedicellate spikelets and 2n = 120 chromosomes are included in B. campii (Swallen) de Wet comb. nov. South American collections of B. springfieldii (Gould) Parodi differ from North American collections in having 2n = 60 rather than 120 chromosomes and in having larger inflorescences as does B. barbinodis. Variety australis de Wet. var. nov. is described to include them.     

Nematicidal activity of Okinawa Island plants on the root-knot nematode Meloidogyne incognita (Kofoid and White) Chitwood

In order to develop biological control methods that are effective against the root-knot nematode Meloidogyne incognita (Kofoid and White) chitwood, the activity of ethanolic and aqueous extracts of wild plant species distributed on Okinawa Island on the viability and mobility of second stage M. incognita juveniles (J2s) was evaluated. Eleven of the 29 extracts immobilized at least half of the J2 stage nematodes in an in vitro assay. Aqueous extracts of Bidens pilosa L. var. radiata Scherff, Hydrocotyle dichondroides Makino, Oxalis corymbosa DC., Oxalis corniculata L., and Stenactis annus (L.) Cass gave 90% or better immobilization activity. Among these, B. pilosa var. radiata had the highest activity. Significant immobilization, lethality, repellence and egg hatching inhibition were observed with extracts from each B. pilosa plant part, but especially from leaves. The effects of plant extracts on the mobility of M. incognita were higher than on the free-living nematode Panagrolaimus sp., suggesting that M. incognita could be suppressed using B. pilosa extracts without significantly affecting beneficial nematodes.     

Development and characterization of microsatellite loci for Rosa odorata var. gigantea Rehder & E. H. Wilson (Rosaceae)

Eighteen microsatellite markers were developed from Rosa odorata var. gigantea (Rosaceae), including 11 new microsatellite markers and 7 modified microsatellite loci having been developed from other Rosa species. About 27 wild individuals from 3 populations were used to screen polymorphism of these 18 microsatellite makers. The average allele number of these markers was 3.9 per locus, ranging from 2 to 9. The expected and observed heterozygosities varied from 0.2711 to 0.8043 and from 0.0370 to 0.5556, respectively. Cross-species amplification in other eight Rosa species showed their potential use for congeneric species. These microsatellite primers will be used for population genetics studies, constructing genetic linkage maps or locating quantitative trait locus (QTL) of R. odorata var. gigantea and related species.     

Differential growth response to arbuscular mycorrhizal fungi and plant density in two wild plants belonging to contrasting functional types

The effect of arbuscular mycorrhizal fungi (AMF) on plant growth was examined in two wild plant species belonging to contrasting functional types: an annual forb (Bidens pilosa, Asteraceae) and a deciduous shrub (Acacia caven, Fabaceae) at three contrasting plant densities (one, two, and three individuals per pot). AMF had a slightly negative effect on B. pilosa when the species grew in isolation while they positively affected A. caven. Positive effects of AMF on shoot mass of A. caven decreased at higher plant densities, while shoot mass of individuals of B. pilosa showed less marked differences between plant densities. When considering total biomass per pot, AMF positively affected A. caven growth while negatively affecting B. pilosa, at all three plant densities. Root/shoot ratio per pot was negatively affected by AMF but not plant density in both species. These findings highlight the importance of including plants belonging to different life forms and/or traits in research regarding the interaction between AMF and intraspecific plant competition.     

不同光照和水分下三叶鬼针草与本地种金盏银盘生长特征的比较研究

为探讨三叶鬼针草(Bidens pilosa)成功入侵机制,利用盆栽试验对不同光照和水分条件下三叶鬼针草与本地种金盏银盘(B.biternata)的生长特征进行了比较研究。结果表明,两物种对光和水的变化均具有较大可塑性,但与金盏银盘相比,在有利环境下三叶鬼针草具有较大的株高、叶面积、生物量;在不利环境下,三叶鬼针草具有较大的比叶面积和叶面积比;除叶面积比和叶生物量比外,三叶鬼针草各生理参数的可塑性指数均高于本地种。这说明三叶鬼针草具有较强的表型可塑性和入侵适应性,这些特性促进了其成功入侵。     

AN OVERVIEW OF THE GENUS PYRRHOPAPPUS (ASTERACEAE: LACTUCEAE) WITH EMPHASIS ON CHLOROPLAST DNA RESTRICTION SITE DATA

The genus Pyrrhopappus in recent systematic treatments has comprised five taxa (four species, one with two varieties), which have now been studied anew using morphogeographical and chloroplast DNA restriction site data. Eight populations, representing all of the recognized taxa of Pyrrhopappus, were digested with 17 restriction enzymes. Only three restriction site differences were found from among 750 restriction sites and no length variations were observed. This contrasts with similar studies, using these same enzymes, on the closely related genus Krigia in which 173 mutation sites and 20 length variations were found among the seven species concerned. Nucleotide sequence divergence values among the species of Pyrrhopappus were extremely low (0.0012) compared to much higher values found in the closely related genus Krigia (0.1270). Three species of Pyrrhopappus are herein recognized: two diploids with 2n = 12 chromosomes, P. carolinianus and P. pauciflorus (including P. multicaulis, P. geiseri and P. rothrockii), and a tetraploid (2n = 24), P. grandiflorus. The tetraploid is partially sympatric with both diploids but is readily recognized by its perennial roots, which bear tuber-like enlargements. These three species presumably arose relatively recently, and the DNA data suggest that neither P. pauciflorus nor P. carolinianus gave rise to the tetraploid P. grandiflorus.     

CHROMOSOME COUNTS OF COMPOSITAE FROM THE UNITED STATES AND MEXICO

Chromosome counts are reported for 126 taxa representing 122 species and 61 genera of Compositae. First reports include two genera, Stylocline (n = 14) and Chromolepis (n = 19), 17 species, two infraspecific taxa, and one interspecific hybrid. Five additional taxa have chromosome numbers differing from previously published accounts. Carminatia is reinstated to generic status.