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1.
Random Amplified Polymorphic DNA (RAPD) showed a high degree of polymorphism in nine species of bamboo, Dendrocalamus giganteus Wall ex Munro, D. asper Becker ex K. Heyn, D. longispathus (Kurz) Kurz, Bambusa vulgaris `Striata', B. ventricosa, B. bambos (L.) A. Voss, B. atra Lindley, Gigantochloa atroviolacea Wdjaja and Arundinaria hindsii, in Sri Lanka. The lowest mean genetic distance of 0.143 was between B. vulgaris and B. ventricosa. They could however be distinguished morphologically. The genetic distances separating D. longispathus from D. giganteus and D. asper were both greater than that between the latter two species, which had a value of 0.313. Although the genetic distances between Bambusa vulgaris, B. ventricosa and B. bambos were relatively small, B. atra separated from them at greater distances. The smaller genetic distances between G. atroviolacea and B. vulgaris, B. ventricosa and B. bambos indicated that G. atroviolacea had a closer affinity to these three Bambusa species than B. atra. A. hindsii with the greatest genetic distances from all other species in the study, was not related to any of them. RAPD analysis was useful in determining the genetic diversity and relationships and in detecting problematic generic assignments.  相似文献   

2.
Two new species of chironomid midges (Rheosmittia arcuata n.sp. and Mesocricotopus loticus n.sp.) are recognized. They may easily be missed in collections due to their small size, and difficulty in collecting from the larval microhabitat (sand substrates for R. arcuata n.sp., low order streams with depositional substrates including gravel, sand, and silt for M. loticus n.sp.). Some morphological features are given to distinguish the new species from similar congeneric forms. The distribution and some ecological information for each species are also briefly discussed.  相似文献   

3.
通过标本考证和野外研究,证实中国文献记载的纤细蛇根草(Ophiorrhiza gracilis Kurz)实为尾瓣蛇根草(O. caudipetala Deb & Monda)错误鉴定,而后者之前仅被报道分布于印度,因此为中国新记录。尾瓣蛇根草具有明显不等大的对生叶片, 花冠裂片背部具长0.6~1 mm的角状突起,易与中国蛇根草属其它种类区分。  相似文献   

4.
报道了叶下珠科算盘子属4种植物在中国6个省区的分布新记录,其中贵州分布新记录有圆果算盘子[Glochidion sphaerogynum (Müll. Arg.) Kurz],广东分布新记录有宽果算盘子(G. oblatum Hook. f.)和台闽算盘子(G. rubrum Blume),海南和广西分布新记录有宽果算盘子,湖南分布新记录有湖北算盘子(G. wilsonii Hutch.),浙江分布新记录有台闽算盘子。  相似文献   

5.
The lectin affinities of -N-acetyl-d-hexosaminidase (E.C.3.2.1.52) from an acute lymphoblastic leukaemic cell-line (CCRF/CEM), a non-malignant lymphoblastic cell-line (SM1) and normal human fibroblasts were studied for both mature and precursor forms of the enzyme. Four immobilised lectins concanavalin A-Sepharose wheat germ agglutinin-Agarose,Ricinus communis agglutinin I-Agarose,Phaseolus vulgaris erythroagglutinin-Agarose and a column of serotonin-Sepharose were used. The activities of -hexosaminidase from fibroblasts and SM1 cells generally behaved similarly while the CCRF/CEM enzyme exhibited different binding patterns. Differences were also noted between precursor and mature enzyme from each cell type consistent with changes in glycosylation between the precursor form and the mature form appearing in the lysosome. These results suggest that changes in the glycosylation of -hexosaminidase, and possibly other lysosomal enzymes, may be associated with malignancy.Abbreviations Con A concanavalin A-Sepharose - RCA-I Ricinus communis agglutinin I-Agarose - WGA wheat germ agglutinin-Agarose - PHA-E Phaseolus vulgaris erythroagglutinin-Agarose - SER serotonin-Sepharose: non-T - non-B ALL non-T, non-B cell acute lyphoblastic leukaemia - 4-MU-GLcNAc 4-methylumbelliferyl 2-acetamido-2-deoxy--D-glucopyranoside  相似文献   

6.
The epifauna associated with two of the most common species of kelp in the Arctic, Laminaria digitata (Hudson) Lamouroux, 1813 and Saccharina latissima (Linnaeus) Lane, , Mayes, Druehl and Saunders 2006 [synonym: L. saccharina (Linnaeus) Lamouroux, 1813] were examined in Kongsfjorden, Svalbard. The aim of this study was to test whether species richness of epifauna was influenced by seasonality of recruitment supply (spring and summer) or by age of the substrate (lamina). From 20 algae specimens (ten—L. digitata, ten—S. latissima), a total of 27 epifaunal taxa were identified with bryozoans as the most species-rich group. Total species richness ranged from one to nine species per lamina. No significant difference in species richness was observed between the two kelp species. In both macroalgae, more epifauna taxa were registered on lamina in May (mean 6) than in August (mean 3). This indicates that the time chosen for sampling had a significant impact on the species richness pattern. The number of epifaunal species was significantly negatively correlated with increasing age of the lamina. There are indications that diversity of the epifauna on lamina is influenced to a large extent by substrate (lamina) surface area, environmental stress and the presence of meroplankton in the water column.  相似文献   

7.
Silene thebana Orph. exBoiss. is transferred as a subspecies toS. fabaria (L.)Sm., resulting in the new combinationS. fabaria (L.)Sm. subsp.thebana (Orph. exBoiss.)Melzh. The chromosome count of 2n = 24 is recorded for the first time for this taxon.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday, 16th October 1986.  相似文献   

8.
The invasion behavior of two climax species,Machilus thunbergii Sieb. et Zucc. andCastanopsis cuspidata (Thunb.) Schottky var.sieboldii (Makino) Nakai, was studied on the 1874 and 1962 lava flows on Miyakejima, Japan. On the 1962 lava, zoochorousM. thunbergii appeared almost only under crowns of pioneeringAlnus sieboldiana Matsum, while bolochorousC. cuspidata var.sieboldii occurred only along the borders of the lava. The three species,A. sieboldiana, M. thunbergii andC. cuspidata var.sieboldii, corresponded, in order, to the temporal sequence of invasion in the boundary forest and the spatial sequence from margin to center on the 1962 lava. Seed or fruit dispersion is important in primary succession in the case of large disturbances.  相似文献   

9.
A new procedure was used to purify the peroxisomal matrix enzyme hydroxypyruvate reductase (HPR) from green leaves of pumpkin (Cucurbita pepo L.) and spinach (Spinacia oleracea L.). Monospecific antibodies were prepared against this enzyme in rabbits. Immunoprecipitation of HPR from watermelon (Citrullus vulgaris Schrad.) yielded a single protein with a subunit molecular weight of 45 kDa. Immunohistochemical labeling of HPR was found exclusively in watermelon microbodies. Isolated polyadenylated mRNA from light-grown watermelon cotyledons was injected into Xenopus laevis oocytes. The heterologous in-vivo translation product of HPR exhibited the same molecular weight as the immunoprecipitate from watermelon cotyledons, indicating the lack of a cleavable extra sequence. The watermelon HPR translated in oocytes was imported into isolated glyoxysomes from castor bean (Ricinus communis L.) endosperm and remained resistant to proteolysis after the addition of proteinase K. The HPR did not change its apparent molecular weight during sequestration; however, it may have changed its conformation.Abbreviations HPR hydroxypyruvate reductase - PMSF phenylmethylsulfonyl fluoride - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis  相似文献   

10.
Decay of the bacteriochlorophyll excited state was measured in membranes of the purple bacteria Rhodospirillum (R.) rubrum, Rhodobacter (Rb.) sphaeroides wild type and Rb. sphaeroides mutant M21 using low intensity picosecond absorption spectroscopy. The excitation and probing pulses were chosen in the far red wing of the long wavelength absorption band, such that predominantly the minor antenna species B896 was excited. The decay of B896 was studied between 77 and 177K under conditions that the traps were active. In all species the B896 excited state decay is almost temperature independent between 100 and 177K, and probably between 100 and 300 K. In this temperature range the decay rates for the various species are very similar and close to 40 ps. Below 100 K this rate remains temperature independent in Rb. sphaeroides w. t. and M21, while in R. rubrum a steep decrease sets in. An analysis of this data with the theory of nuclear tunneling indicates an activation energy for the final transfer step from B896 to the special pair of 70cm-1 for R. rubrum and 30cm-1 or less for Rb. sphaeroides.Abbreviations B880 and B896 the main and long wavelength bacteriochlorophyll's of the LH-1 antenna - RC reaction centre - P special pair in the RC  相似文献   

11.
报道中国柿科(Ebenaceae)柿属植物一新记录种——长柱柿(Diospyros brandisiana Kurz),并描述了该新记录种的形态特征和生境分布。该种为该属中国分布的唯一具老茎生花的种类。凭证标本存放于中国科学院昆明植物研究所标本馆(KUN)。  相似文献   

12.
Kengyilia laxiflora (2n = 42) was cytogenetically studied with testersK. hirsuta (2n = 42, PPStStYY) andRoegneria kamoji (2n = 42, HHStStYY). Our data suggested thatK. laxiflora may possess a modified P genome, the P1. Its St and Y genomes may also contain some structural changes and are more closely related to the St and Y genomes ofK. hirsuta than to those ofR. kamoji. Kengyilia laxiflora is reproductively separated from bothK. hirsuta andR. kamoji. These results indicated thatK. laxiflora is a good species in the genusKengyilia.  相似文献   

13.
Eight new species of the genus Tricoma are described from the Mediterranean: Tricoma (Tricoma) apophysis sp.n., Tricoma (T.) latispicula sp.n., Tricoma (T.) corsicana sp.n., Tricoma (T.) pygmaea sp.n., Tricoma (T.) vincxae sp.n., Tricoma (T.) duopapillata sp.n., Tricoma (T.) setosa sp.n. and Tricoma (Quadricoma) tripapillata sp.n.. All are noteworthy for being small.  相似文献   

14.
15.
The cerebrosides were first isolated by Thudicum in 1874 and the structures were established by Carteret al. in 1950 (for review, see [2]). In 1961 Shapiro and Flowers [3] reported the first total synthesis of a cerebroside1 (Fig. 1) which was identified with the natural sample, only through comparison of their i.r. data. In order to confirm the absolute configuration at C-2 of natural cerebroside1, we describe here an unambiguous synthesis of two stereoisomeric cerebrosides1 and2, and found that the1H-NMR spectra of the synthetic1 (Fig. 2) was completely identical with that of the natural cerebroside reported recently by Dabrowskiet al. [4].In planning the synthetic route, the target structures1 and2 were disconnected at the dotted lines to give three key synthetic intermediates3, 4 and5 or6 (Fig. 1).Abbreviations Bu butyl - Ph phenyl - t-BuPh2SiCl t-butyldiphenylsilyl chloride - MTPA -methoxy--trifluoromethylphenylacetic acid - THF tetrahydrofuran Part 36 in the series Synthetic Studies on Cell-surface Glycans, for part 35, see [1]  相似文献   

16.
郭林 《菌物学报》1995,14(Z1):163-168
本文报道炭黑粉菌一新种,即细叶蒿草炭黑粉菌(Anthracoidea filifoliae L. Guo sp.nov.)和4个我国新记录种:1)角孢炭黑粉菌(A. angulata(H. Sydow) Boidol & Poclt), 2)黍状苔炭黑粉菌(A. paniceae Kukkenen), 3)狼尾草团黑粉菌(Sorosporium penniseti Mundkur)和4)米勒粘孢黑粉菌(Tolyposporium muellerianum (Thuemen) McAlpine)。  相似文献   

17.
18.
Twenty-seven morphological characters from 111 heteromorphic deutonymphs of the mite genus Chaetodactylus Rondani (Acari: Chaetodactylidae) were analyzed. The mites were collected from four species of bees of the genus Lithurgus Berthold (Hymenoptera: Megachilidae) in continental North America. Principal component and canonical variates analyses on Darroch and Mosimann shape and size-and-shape variables revealed the presence of three cryptic species. Chaetodactylus gibbosi sp. n. (Florida) is geographically isolated from C. lithurgi sp. n. distributed in Texas, New Mexico, Arizona, Colorado, and Idaho. Sympatric C. lithurgi and C. abditus sp. n. (USA: Arizona, Mexico: Socorro Is.) are seasonally isolated in Arizona. Chaetodactylus gibbosi is associated with a single bee species, Lithurgus gibbosus Smith in Florida. The host range of C. lithurgi includes bees flying predominantly in the spring: L. apicalis Cresson, L. littoralis Cockerell, and western L. gibbosus. Chaetodactylus abditus sp. n. is associated with L. planifrons Friese and L. echinocacti Cockerell, flying predominantly in the fall in Arizona. No distinct groups separated by geographic locality or size were detected in any species. A six-variable model developed by the canonical variates analysis and estimated using jackknife resampling and external validation (n=100) is capable of classifying the three species with 100% accuracy. Factors that influenced speciation of cryptic species of Chaetodactylus associated with Lithurgus are discussed. Based on morphological and geographical data and data on mite associates, the western and eastern populations of the bee L. gibbosus are distinct. Therefore, the taxonomic status of L. gibbosus s. lat. should be reevaluated.  相似文献   

19.
广义无心菜属(Arenaria L.s.l.)是石竹科(Caryophyllaceae)中分类较为困难的大属之一,基于分子系统学研究结果该属目前已被拆分为多属.基于形态学证据,桃色无心菜(Arenaria melandryoides Edgew.)被置于无心菜属齿瓣亚属[subg.Odontostemma(G.Don)...  相似文献   

20.
A correspondence between RFLP patterns and gliadin alleles at the Gli-1 and Gli-2 loci was established in a set of 70 common wheat (T.aestivum L.) cultivars using -gliadin (K32) and -gliadin (pTU1) specific probes. All Gli-B1 and Gli-D1 alleles which differed in encoded -gliadins showed definite RFLP patterns after hybridization with the K32 probe. Two groups of Gli-B1 alleles, Gli-B1b-like and Gli-B1e-like, were identified, and these could originate from distinct genotypes of the presumptive donor of the B-genome. Intralocus recombination and/or gene conversion as well as small deletions, gene silencing and gene amplification were assumed to be responsible for the origin of new gliadin alleles. Silent -gliadin sequences were shown to exist in all of the genotypes studied. K32 also differentiated Gli-A1a from all other Gli-A1 alleles as well as the Gli-B11 allele in cultivars carrying the 1B/1R (wheat/rye) translocation. PTU1 was shown to recognize several Gli-A2 alleles, but not the Gli-B2 or Gli-D2 alleles. Moreover, this probe hybridized to chromosome 1R sequences suggesting the existence of rye gene(s), probably silent, for -gliadin-like proteins on chromosome 1R.  相似文献   

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