三种北极石竹科植物的挥发油成分及其化学分类学意义

通过GC/MS方法对采自北极的Stellaria crassipes,Cerastium arcticum和Cerastium regelii 3种石竹科植物挥发油成分进行了研究,共得到54种化学成分,对这些挥发油成分的进一步分析,证明了Stellaria和Cerastium具有较近的亲缘关系。     

三种北极石竹科植物中的环肽及石竹科环肽的化学分类和分布意义

用HPLC等现代分离技术,从各样少于100g的北极3种石竹科(Caryophyllaceae)植物StellariacrassipesHult.、CerastiumarcticumLange和C.regeliiOstenf.中分得5个新环肽,分别命名为arcticuminA(1)、arcticuminB(2)、arcticuminC(3)、regelinA(4)和crassipinB(5),并通过FAB -MS和氨基酸组成分析初步鉴定了它们的结构;通过对北极石竹科环肽与青藏高原石竹科环肽的比较,证明了环肽是石竹科的特征成分以及北极地区是石竹科植物分布中心的一个区域。     

三种北极石竹科植物中的环肽及石竹科环肽的化学分类和分布意义

用HPLC等现代分离技术,从各样少于100g的北极3种石竹科(Caryophyllaceae)植物Stellaria crassipes Hult.、Cerastium arcticum Lange和C.regelii Ostenf.中分得5个新环肽,分别命名为arcticumin A(1)、arcticumin B(2)、arcticumin C(3)、regelin A(4)和crassipin B(5),并通过FAB -MS和氨基酸组成分析初步鉴定了它们的结构;通过对北极石竹科环肽与青藏高原石竹科环肽的比较,证明了环肽是石竹科的特征成分以及北极地区是石竹科植物分布中心的一个区域.     

Micromorphological features of the seed surface of Schisandraceae and their systematic significance

Micromorphological features of the seed surface of the Schisandraceae are reported for the first time. One hundred and seventeen seed samples from 92 populations, representing 24 species, seven varieties and one form of the Schisandraceae, were examined and photographed under scanning electron microscope (SEM). Micromorphological features of seed surfaces of the Schisandraceae are little affected by the habitats in which plants grow, and are quite constant within species, therefore they can be used as reliable diagnostic characters to distinguish species. The following taxonomic treatments are not supported by micromorphological features observed: ( 1 ) To reduce Schisandra wilsoniana A. C. Smith to S. henryi Clarke; (2) To reduce S. neglecta A. C. Smith, S. arisanensis Hayata, S. viridis A. C. Smith, S. sphenanthena Rehd. & Wils., S. gracilis A. C. Smith, S. micrantha A. C. Smith and S. lancifolia var. polycarpa Z. He to S. elongata ( Bl. ) Baill.; (3) To reduce S. henryi var. longipes (Merr. & Chun) A. C. Smith, S. tomentella A. C. Smith and S. pubescens var. pubinervis (Rehd. & Wils.)A. C. Smith to S. pubescens Hemsl. & Wils.; (4) To reduce S. rubriflora(Franch.)Rehd. & Wils., S. flaccidiramosa C. R. Sun, S. incarnata Stapf, S. sphaerandra Stapf, S. sphaerandra f. pallida A. C. Smith and S. glaucescens Diels to S. grandiflora ( Wall. ) Hook. f. & Thoms.; (5) To reduce Schisandra wilsoniana to S. bicolor Cheng; (6) To reduce S. lancifolia var. polycarpa to S. neglecta; (7) To raise S. henryi var. longipes to S. longipes(Merr. & Chun)R. M. K. Saunders; (8) To reduce Kadsura polysperma Yang to K. heteroclita(Roxb. )Craib. The relationship between Schisan-dra Michx. and Kadsura Kaempf. ex Juss. revealed by the micromorphological features of seed surface is very similar to that revealed by pollen morphology, namely these two genera might have originated from a common ancestor and then evolved along two different routes. However the probability of a more complicated relationship between the two genera than we have known hitherto can not be excluded. The general evolutionary level of Kadsura seems to be higher than that of Schisandra. Therefore, the viewpoint that Kadsura is more primitive than Schisandra is not supported.     

Studies on theStellaria longipes complex (Caryophyllaceae): Isozyme variability and the relationship betweenStellaria longipes andS. longifolia

Genetic variation within and the relationship betweenStellaria longipes Goldie andS. longifolia Muhl. were studied. Ten enzyme systems were assessed in eight natural populations ofS. longipes (25 loci) and three ofS. longifolia (20 loci) using starch and polyacrylamide gel electrophoresis. Patterns of population differentiation corresponded to geographic distance. There was no evidence that polyploidS. longipes had greater electrophoretic variability than diploidS. longipes. The isozyme data confirmed extensive population differentiation in these species and, within that context, a relatively close relationship betweenS. longipes andS. longifolia. It was postulated that diploids of these two species might be the progenitors of tetraploidS. longipes.     

Morphological variation among members of theStellaria longipes complex:S. longipes,S. longifolia,andS. porsildii (Caryophyllaceae)

Morphological relationships were investigated among diploidStellaria porsildii, polyploidS. longipes, and diploidS. longifolia. Canonical discriminant analysis, based on a priori assumptions to maximize differences among groups, showed thatS. longipes clusters equally distant between the two diploid species along an axis connecting the diploids' centroids, but it differs along an axis perpendicular to this axis. The intermediacy along the former axis is evidence thatS. longipes is an amphiploid derived fromS. longifolia andS. porsildii. The divergence along the latter axis may be attributable to adaptively valuable heterotic traits which were retained following amphidiploidization. The only morphological discontinuity occurred between the two diploids, whereas the morphological range ofS. longipes overlapped the range of both diploids forming a continuum. The lack of discrete clusters is likely due to hybridization and introgression withS. longifolia on one hand, and convergence of traits betweenS. longipes var.monantha andS. porsildii on the other. High a posteriori assignments in classificatory discriminant analysis supports the separation ofS. longipes var.monantha from otherS. longipes specimens. AlthoughS. longipes var.monantha grouped close toS. porsildii, the two groups separate based on leaf shape traits. Overall results support, firstly, the hypothesis thatS. porsildii is a diploid parent species which by hybridizing withS. longifolia gave rise to polyploidS. longipes. Secondly, results suggest thatS. longipes var.monantha converged morphologically towardsS. porsildii relatively recently due to ecological specialization, and merits distinction at least as a variety ofS. longipes.     

The use of double fluorescence in situ hybridization to physically map the positions of 5S rDNA genes in relation to the chromosomal location of 18S-5.8S-26S rDNA and a C genome specific DNA sequence in the genus Avena.

A physical map of the locations of the 5S rDNA genes and their relative positions with respect to 18S-5.8S-26S rDNA genes and a C genome specific repetitive DNA sequence was produced for the chromosomes of diploid, tetraploid, and hexaploid oat species using in situ hybridization. The A genome diploid species showed two pairs of rDNA loci and two pairs of 5S loci located on both arms of one pair of satellited chromosomes. The C genome diploid species showed two major pairs and one minor pair of rDNA loci. One pair of subtelocentric chromosomes carried rDNA and 5S loci physically separated on the long arm. The tetraploid species (AACC genomes) arising from these diploid ancestors showed two pairs of rDNA loci and three pairs of 5S loci. Two pairs of rDNA loci and 2 pairs of 5S loci were arranged as in the A genome diploid species. The third pair of 5S loci was located on one pair of A-C translocated chromosomes using simultaneous in situ hybridization with 5S rDNA genes and a C genome specific repetitive DNA sequence. The hexaploid species (AACCDD genomes) showed three pairs of rDNA loci and six pairs of 5S loci. One pair of 5S loci was located on each of two pairs of C-A/D translocated chromosomes. Comparative studies of the physical arrangement of rDNA and 5S loci in polyploid oats and the putative A and C genome progenitor species suggests that A genome diploid species could be the donor of both A and D genomes of polyploid oats. Key words : oats, 5S rDNA genes, 18S-5.8S-26S rDNA genes, C genome specific repetitive DNA sequence, in situ hybridization, genome evolution.     

巴音布鲁克大尤尔都斯盆地野生种子植物区系研究

基于野外实地调查,采集植物标本鉴定并结合相关文献资料整理,构建新疆巴音布鲁克大尤尔都斯盆地野生种子植物名录,在此基础上对该地区野生种子植物区系进行研究.结果表明:(1)巴音布鲁克大尤尔都斯盆地共有野生种子植物60科261属770种.(2)优势科有禾本科、菊科、豆科、石竹科、蔷薇科、十字花科、莎草科、毛茛科等11个科,表征科有豆科、龙胆科、石竹科、禾本科4个科.(3)区系地理成分以温带分布型为主,其中在科级水平上,温带分布型所属科共有30科,占到总科数(不含世界广布科)的88.24％;在属级水平上,温带性质分布型的属有220属,占总属数(不含世界广布属)的97.78％;同时该地区植物物种与地中海、中亚、西亚交流相对较多,而与东亚和热带交流很少.(1)本地区无中国特有属,但有中国特有种55个,其中新疆特有种32个.     

Induction of a β-phaseolin promoter by exogenous abscisic acid in tobacco: developmental regulation and modulation by external sucrose and Ca2+ ions

Using degenerate oligonucleotides that correspond to conserved amino acid residues of known 1-aminocyclopropane-1-carboxylic acid (ACC) synthases, we cloned a genomic fragment that encodes ACC synthase in Stellaria longipes. Southern analysis suggests that ACC synthase is encoded by a small gene family comprising about 4 members. We isolated four unique ACC synthase cDNA clones under different growth conditions from alpine and prairie ecotypes of S. longipes. Northern analyses suggest that ACC synthase genes are differentially and synergistically regulated by photoperiod and temperature. Such differential regulation of ACC synthase genes positively correlate with the levels of ACC and ethylene. Since ethylene has previously been shown to partly control the stem elongation plasticity in S. longipes, we propose that differential regulation of ACC synthase genes may represent one of the underlying molecular mechanisms of phenotypic plasticity in S. longipes.     

Spatial and temporal patterns of carabid activity-density in cereals do not explain levels of predation on weed seeds

Seed predation is an important component of seed mortality of weeds in agro-ecosystems, but the agronomic use and management of this natural weed suppression is hampered by a lack of insight in the underlying ecological processes. In this paper, we investigate whether and how spatial and temporal variation in activity-density of granivorous ground beetles (Coleoptera: Carabidae) results in a corresponding pattern of seed predation. Activity-density of carabids was measured by using pitfall traps in two organic winter wheat fields from March to July 2004. Predation of seeds (Capsella bursa-pastoris, Lamium amplexicaule, Poa annua and Stellaria media) was assessed using seed cards at the same sites and times. As measured by pitfall traps, carabids were the dominant group of insects that had access to the seed cards. In the field, predation of the four different species of seed was in the order: C. bursa-pastoris>P. annua>S. media>L. amplexicaule; and this order of preference was confirmed in the laboratory using the dominant species of carabid. On average, seed predation was higher in the field interior compared to the edge, whereas catches of carabids were highest near the edge. Weeks with elevated seed predation did not concur with high activity-density of carabids. Thus, patterns of spatial and temporal variation in seed predation were not matched by similar patterns in the abundance of granivorous carabid beetles. The lack of correspondence is ascribed to effects of confounding factors, such as weather, the background density of seeds, the composition of the carabid community, and the phenology and physiological state of the beetles. Our results show that differences in seed loss among weed species may be predicted from laboratory trials on preference. However, predator activity-density, as measured in pitfall traps, is an insufficient predictor of seed predation over time and space within a field.     

Genomic diversity in aneudiploid (2n = 38) and diploid (2n = 40) Glycine tomentella revealed by cytogenetic and biochemical methods.

Of the 15 perennial species of the subgenus Glycine Willd., G. tomentella Hayata is unique in that it has four cytotypes (2n = 38, 40, 78, and 80) and a wide range of geographical distributions. The objective of this study was to uncover the genomic diversity among accessions of aneudiploid (2n = 38) and diploid (2n = 40) G. tomentella based on crossability rate, hybrid seed and seedling viability, meiotic chromosome pairing of F1 hybrids, and seed protein and protease inhibitor profiles. Aneudiploid and diploid G. tomentella accessions were divided into two (D1 and D2) and three [D3(A,B,C), D4, and D5] groups, respectively, based on previous isozyme studies. Crossability rate, intergenomic hybrid viability, degree of chromosome pairing, total seed protein profiles, and trypsin and chymotrypsin inhibitor banding patterns confirmed the isozyme grouping with minor disagreements. A consistent variation was not observed among the aneudiploid accessions in any method of analysis used in this study. Similarly, cytogenetic analysis and the total seed protein profiles did not show dissimilarity among the accessions from Papua New Guinea (PNG; the D3 group) and north of Mitchell River in Northern Queensland [N.Qld(n)]. However, trypsin and chymotrypsin inhibitor analysis revealed that the PNG accessions were distinctly different from N.Qld(n) accessions. The D4 and D5 group accessions were clearly distinguishable by both cytogenetic and biochemical methods. Thus, this study indicates the presence of four genomic groups among G. tomentella (2n = 38, 40) accessions, including the aneudiploids D1 and D2 in one group and diploids in three groups (D3, D4, and D5). These findings will be useful in further genome analysis and add to our present understanding of the biosystematics of the genus Glycine.     

石竹科繁缕属与孩儿参属的数量分类

石竹科繁缕属(Stellaria L.)和孩儿参属(Pseudostellaria Pax)的关系一直备受关注。为了弄清它们之间的关系及属下分类等问题,选择繁缕属22种和孩儿参属8种,共30种植物51个形态特征,利用NTSYS-pc 2.10e软件中的UPGMA聚类分析方法和主坐标分析方法,对这2个属进行数值分类学研究。结果表明,繁缕属与孩儿参属是2个自然类群,除繁缕属的繁缕(S.media(L.)Cyr.)和鸡肠繁缕(S.neglecta Weihe ex Bluff et Fingerh)在聚类中不能分开外,其它物种都能很好地分开。两属有较近的关系,其中巫山繁缕(S.wushanensis Williams)是过渡种。此外,数量分类结果建议将细叶孩儿参(P.sylvatica(Maxim.)Pax)作为一个独立组处理。对性状的主坐标排序分析显示,根的形状、叶缘质地、花的形态(是否具花瓣、花瓣长度、花瓣裂数、深裂还是浅裂)和种子表面纹饰(是否具齿轮状、疣状突起)等在繁缕属与孩儿参属的分类中具有重要作用。     

中国石竹科一些修订与增补

为编写中国植物志英文版,对我国石竹科植物(不包括繁缕属、无心菜属和蝇子草属)进行了修订,归并2种,增补9种、2亚种、1变种,并对一些属、种的学名和文献加以校订。     

Ancestry of American polyploid Hordeum species with the I genome inferred from 5S and 18S-25S rDNA

* BACKGROUND AND AIMS: The genus Hordeum exists at three ploidy levels (2x, 4x and 6x) and presents excellent material for investigating the patterns of polyploid evolution in plants. Here the aim was to clarify the ancestry of American polyploid species with the I genome. * METHODS: Chromosomal locations of 5S and 18S-25S ribosomal RNA genes were determined by fluorescence in situ hybridization (FISH). In both polyploid and diploid species, variation in 18S-25S rDNA repeated sequences was analysed by the RFLP technique. * KEY RESULTS: Six American tetraploid species were divided into two types that differed in the number of rDNA sites and RFLP profiles. Four hexaploid species were similar in number and location of both types of rDNA sites, but the RFLP profiles of 18S-25S rDNA revealed one species, H. arizonicum, with a different ancestry. * CONCLUSIONS: Five American perennial tetraploid species appear to be alloploids having the genomes of an Asian diploid H. roshevitzii and an American diploid species. The North American annual tetraploid H. depressum is probably a segmental alloploid combining the two closely related genomes of American diploid species. A hexaploid species, H. arizonicum, involves a diploid species, H. pusillum, in its ancestry; both species share the annual growth habit and are distributed in North America. Polymorphisms of rDNA sites detected by FISH and RFLP analyses provide useful information to infer the phylogenetic relationships of I-genome Hordeum species because of their highly conserved nature during polyploid evolution.     

Genome differentiation between two closely related species of Sideritis L. (Lamiaceae)

We have analysed the karyotype structure, DNA amounts and seed protein profiles of three isolated populations of two species: S. saetabensis and S. tragoriganum. These species are closely related from a karyological and morphological point of view. The differences in karyotypes and seed protein profiles between species and among populations could be the result of the differentiation that they are undergoing at present due to geographical isolation.     

Mapping of rDNA on the chromosomes of Eleusine species by fluorescence in situ hybridization

Mapping of rDNA sites on the chromosomes of four diploid and two tetraploid species of Eleusine has provided valuable information on genome relationship between the species. Presence of 18S-5.8S-26S rDNA on the largest pair of the chromosomes, location of 5S rDNA at four sites on two pairs of chromosomes and presence of 18S-5.8S-26S and 5S rDNA at same location on one pair of chromosomes have clearly differentiated E. multiflora from rest of the species of Eleusine. The two tetraploid species, E. coracana and E. africana have the same number of 18S-5.8S-26S and 5S rDNA sites and located at similar position on the chromosomes. Diploid species, E. indica, E. floccifolia and E. tristachya have the same 18S-5.8S-26S sites and location on the chromosomes which also resembled with the two pairs of 18S-5.8S-26S rDNA locations in tetraploid species, E. coracana and E. africana. The 5S rDNA sites on chromosomes of E. indica and E. floccifolia were also comparable to the 5S rDNA sites of E. africana and E. coracana. The similarity of the rDNA sites and their location on chromosomes in the three diploid and two polyploid species also supports the view that genome donors to tetraploid species may be from these diploid species.     

Stellaria devendrae sp. nov. (Caryophyllaceae) from western Himalaya,India

Stellaria devendrae sp. nov. (Caryophyllaceae) is here described and illustrated from the Uttarakhand state of the Indian western Himalaya. It differs from the allied S. monosperma Buch.‐Ham. ex D. Don and S. paniculata Edgew. in having sub‐sessile, oblanceolate or obovate leaves with non amplexicaul, rounded to sub‐auricled leaf base; an inflorescence of a terminal, regularly and simply branched panicle of cymes; larger flowers (5–8 mm across); 5‐lobed floral disc; relatively larger sepals (4–7 mm long); petal lamina lobed for more than 1/2 to 4/5 of the lamina; filaments opposite sepals with prominent nectar glands at base; adjoining filaments not fused at base, and an inconspicuously reticulate‐papillate seed surface.     

Studies on the seed transmission of cucumber mosaic virus in chickweed (Stellaria media) in relation to the ecology of the virus

Cucumber mosaic virus (CMV) was transmitted in the seed of infected Stellaria media plants. The rate of seed transmission varied both in manually infected plants (3–21%) and in plants grown from infected seed (21–40%). In naturally infected plants the rates of transmission found were 4–29%. Seeds recovered from field soil carried 4–5% infection and in infected seed placed in the soil the virus persisted for at least 5 months. Seed transmission of CMV also occurred in infected Lamium purpureum (4%), Cerastium holosteoides (2%) and Spergula arvensis (2%) but it could not be demonstrated in six other more common weed species in five botanical families. Seed transmission in Stellaria media occurred with a British (W) and an American (Y) strain of CMV. The virus was shown to occur in S. media pollen. The importance of CMV-infected S. media seed in the soil in relation to the epidemiology of the virus is discussed.     

Effect of diet on the fecundity of three carabid beetles

Abstract In the present study, the importance of diet in terms of fecundity is compared for three species of the carabid genus Amara (Coleoptera: Carabidae), using an insect diet, two types of seed diet (Capsella bursa‐pastoris, Stellaria media) and a mixed diet. It is expected that the species of carabid studied have different food requirements for reproduction. Diet affects reproduction performance and egg production significantly. A mixed diet and both single‐seed diets are suitable for reproduction in Amara aenea (DeGeer) because a higher proportion of the females reproduce and lay significantly more eggs than on a purely insect diet. Females of Amara familiaris (Duftschmid) do not reproduce unless provided with seeds of S. media. Seeds of C. bursa‐pastoris or a mixed diet are equally suitable diets for reproduction of Amara similata (Gyllenhal); a diet of insects or seeds of S. media is unsuitable. The results support the hypothesis that the species under investigation have specific food requirements, suggesting that seed feeding has evolved to different degrees in particular species: A. aenea is omnivorous, whereas A. familiaris and A. similata specialize on the seed of a particular plant species or family. This resource partitioning facilitates co‐occurrence of carabid species.