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1.
Prickly acacia, Acacia nilotica subsp. indica (Benth.) Brenan, a major weed of the Mitchell Grass Downs of northern Queensland, Australia, has been the target of biological control projects since the 1980s. The leaf-feeding caterpillar Cometaster pyrula (Hopffer) was collected from Acacia nilotica subsp. kraussiana (Benth.) Brenan during surveys in South Africa to find suitable biological control agents, recognised as a potential agent, and shipped into a quarantine facility in Australia. Cometaster pyrula has a life cycle of approximately 2 months during which time the larvae feed voraciously and reach 6 cm in length. Female moths oviposit a mean of 339 eggs. When presented with cut foliage of 77 plant species, unfed neonates survived for 7 days on only Acacia nilotica subsp. indica and Acacia nilotica subsp. kraussiana. When unfed neonates were placed on potted plants of 14 plant species, all larvae except those on Acacia nilotica subsp. indica and Acacia nilotica subsp. kraussiana died within 10 days of placement. Cometaster pyrula was considered to be highly host specific and safe to release in Australia. Permission to release C. pyrula in Australia was obtained and the insect was first released in north Queensland in October 2004. The ecoclimatic model CLIMEX indicated that coastal Queensland was climatically suitable for this insect but that inland areas were only marginally suitable.  相似文献   

2.
The composition of the essential oil from the wormwood sage (Artemisia frigida Willd., Asteraceae) of populations growing in the Altai Territory, the Altai Republic, the Khakass Republic, the Tuva Republic, and the East-Kazakhstan region of the Republic of Kazakhstan and the representative species of the silver-leaved wormwood Artemisia argyrophylla Ledeb. growing in the Republic Altai has been studied by chromato-mass spectrometry. An analysis of 15 samples of the essential oil from A. frigida obtained over a period from 1999 to 2007 indicates that samples from different populations have similar sets of the main components: α-pinene (0.2–7.8%), camphene (1.9–5.8%), 1,8-cineole (8.9–33.8%), camphor (6.7–40.0%), borneol (3.9–12.3%), terpine-4-ol (1.5–6.5%), bornyl acetate (1.4–22.0%), and germacrene D (1.4–14.6%). Some samples contain substantial amounts of α- and β-thujones (in total up to 19.1%), which are completely absent in other samples. Some samples contain santolina alcohol (up to 13.8%) and its acetate (up to 4.8%). As differentiated from A. frigida, the essential oil of A. argyrophylla contains yomogi alcohol (1.2%), artemisia ketone (12.9%), artemisia alcohol (3.1%), artemisia alcohol acetate (3.9%), and small amounts of camphor (3.2%), borneol (0.3%), and bornyl acetate (0.2%).  相似文献   

3.
Antioxidant activity of fruit bodies of Laetiporus sulphureus (Bull.: Fr.) Murr. (Polyporales) obtained by the natural plantation growing method in Pribaikal’e (Irkutsk region) has been studied. It was determined that the ethyl acetate fraction of L. sulphureus, which was chromatographically separated into seven compounds identified as quercetin, kaempferol, (+)-catechin, p-coumaric, gallic, caffeic, and chlorogenic acids was characterized with more expressed antioxidant activity. All compounds were extracted from this basidiomycete species for the first time. The quantitative amount of the substances isolated from L. sulphureus was determined by HPLC. It was found that antioxidant activity of preparations obtained from L. sulphureus is conditioned by phenolic compounds.  相似文献   

4.
Sixty-eight cultures of lactic acid bacteria were isolated and identified from national fermented milk drinks (airan, koumiss, kurunga, shubat) home-made in different regions of the Republic of Kazakhstan and the Buryat Republic of Russia. The cultures of lactic acid bacteria of the genus Lactobacillus were identified as L. paracasei and L. rhamnosus related to the L. casei group and as L. brevis, L. buchneri, L. diolivorans, and L. parabuchneri (the L. buchneri group) using the classical microbiological methods and on the basis of the 16S rRNA gene sequence analysis. The polymorphism of the nucleotide sequences of the genes groEL, rpoB, and rplB encoding specific proteins was studied for intraspecific differentiation of the lactobacilli. The analysis of these genes allowed a more accurate identification of the lactobacilli that are genetically and phenotypically related to the L. casei group as L. paracasei subsp. paracasei and L. paracasei subsp. tolerans. The gene nucleotide sequences of all the genotyped strains were deposited in the GenBank database.  相似文献   

5.
The taxonomic positions, origin, and kinship of various forms of the Altai gray wolf remain debatable. A protocol for simple sequence repeat analysis, which is among the basic tools in phylogeographical studies, has been developed and tested. The study was conducted with 97 gray wolf (Canis lupus L.) individuals from populations inhabiting the plain-steppe, foothill forest-steppe, and mountain-taiga ecotopes of Altai Krai and the Altai Republic. The SSR loci chosen as molecular markers are highly efficient. The results confirm that the forest-steppe Altai gray wolf population is a part of the mountain-taiga population.  相似文献   

6.

Background  

Our laboratories have previously reported on the experimental infection of cattle with Mycobacterium avium subsp paratuberculosis (M. paratuberculosis) using an intratonsillar infection model. In addition, we have recently developed a partial protein array representing 92 M. paratuberculosis coding sequences. These combined tools have enabled a unique look at the temporal analysis of M. paratuberculosis antigens within the native host. The primary objective of this study was to identify M. paratuberculosis antigens detected by cattle early during infection. A secondary objective was to evaluate the humoral immune response in cattle during the initial year of infection.  相似文献   

7.
A numerical taxonomic study was performed on 148 isolates of Gram-negative, heterotrophic, facultative anaerobic bacteria isolated from amberjack (Seriola dumerili) and its surrounding culture water. The study included 30 type and reference strains belonging to genera Vibrio, Listonella, and Photobacterium. The strains were characterized by 109 morphological, biochemical, physiological, and nutritional tests. Cluster analysis of similarity matrices obtained with SSM and SJ coefficients was carried out. UPGMA (unweighted pair group mathematical average) analysis defined 11 phena at SSM values ≥ 86%. Nine phena were identified as Vibrio alginolyticus, V. fischeri, V. harveyi, V. carchariae, V. mediterranei, V. splendidus, V. furnissii, V. parahaemolyticus, and Photobacterium damselae subsp. damselae. The two latter comprised strains isolated from diseased fish. Received: 27 March 2002 / Accepted: 24 May 2002  相似文献   

8.
We present data on the habitat, density, and spatial distribution of Rivulus giarettai, and discuss some biotic and abiotic variables related to its abundance in Free Flowing Waters (FFW) and Dam Reservoirs (DR) in palm grove (Mauritia flexuosa) marshes (Veredas) in Uberlandia, Minas Gerais, southeastern Brazil. The mean density (individuals/plot) of R. giarettai was about 13 times higher in FFW than in DR. In FFW, the density of R. giarettai was highest at intermediate amounts of substrate (plant mass) and it was positively rank-correlated with the depth, and the number of arthropods. Individuals occurred in an aggregated distribution. The aggregated pattern could be related to a concentration of individuals in microhabitats neither too much exposed nor completely saturated by plants. R. giarettai was relatively abundant and tolerant to slight man-made habitat modifications. Damming appeared to be especially problematic by negatively affecting its density.  相似文献   

9.
Melanin complex was isolated from mycelium of the basidiomycete Laetiporus sulphureus (Bull.: Fr.) Murr (with a yield of 2.49% of the dry weight). UV and IR spectroscopies, gel chromatography, and alkaline cleavage assay demonstrated that the isolated melanin was heterogeneous and belonged to the dihydronaphthalene type. 13C-NMR data suggested that aromatic fragments were dominant in the melanin structure. In vitro study of the antioxidant action demonstrated that the L. sulphureus melanin displayed a radical-scavenging activity and the ability to inactivate hydrogen peroxide and nitrogen(II) oxide molecules and to chelate iron(II) ions.  相似文献   

10.
11.

Background  

Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental in vitro IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 Streptococcus gallolyticus subsp. gallolyticus strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms in vitro was examined in order to reveal features of S. gallolyticus subsp. gallolyticus endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors gtf, pilB, and fimB by PCR.  相似文献   

12.
Zoocin A is a streptococcolytic enzyme produced by Streptococcus equi subsp. zooepidemicus strain 4881. The zoocin A gene (zooA) and the gene specifying resistance to zoocin A (zif) are adjacent on the chromosome and are divergently transcribed. Twenty-four S. equi subsp. zooepidemicus strains were analyzed to determine the genetic difference among three previously characterized as zoocin A producers (strains 4881, 9g, and 9h) and the 21 nonproducers. LT-PCR and Southern hybridization studies revealed that none of the nonproducer strains possessed zooA or zif. RAPD and PFGE showed that the 24 strains were a genetically diverse population with eight RAPD profiles. S. equi subsp. zooepidemicus strains 9g and 9h appeared to be genetically identical to each other but quite different from strain 4881. Sequences derived from 4881 and 9g showed that zooA and zif were integrated into the chromosome adjacent to the gene flaR. A comparison of these sequences with the genome sequences of S. equi subsp. zooepidemicus strains H70 and MGCS10565 and S. equi subsp. equi strain 4047 suggests that flaR flanks a region of genome plasticity in this species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

13.
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers, which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects.  相似文献   

14.
Distribution data on Cardamine amara L. in Serbia and Republic of Macedonia are presented, together with a short review of the history of taxonomic treatment of C. amara in this area. C. amara subsp. balcanica Marhold, Ančev & Kit Tan is reported as a new taxon both for the flora of Serbia and flora of Republic of Macedonia and the occurrence of C. amara subsp. amara in Serbia was confirmed.  相似文献   

15.
ITS sequences determined for 53 Erysiphe specimens on Syringa and Ligustrum collected in Europe, East Asia, and North and South America were divided into two ITS groups, S and K types. Phylogenetic analysis showed that these two ITS types do not share a common ancestor and form separate clades. The K type on Ligustrum was identified as Erysiphe ligustri based on the three-dimensional branching pattern of appendages. Morphological observations showed that there are some morphological differences—pigmentation of appendages and number of ascospores per ascus—between the S and K types on Syringa. Based on these morphological observations, the S and K types on Syringa were identified as E. syringae and E. syringae-japonicae, respectively. The recent abundant production of chasmothecia by lilac powdery mildew in Europe was caused by E. syringae-japonicae introduced from East Asia. DNA sequence analyses of the rDNA ITS region and the 28S rDNA, tub2, CYP51, and Chs1 genes did not support an interspecific hybrid origin for E. syringae-japonicae. Haplotype analysis suggested that E. syringae originated in North America and independently migrated to East Asia and Europe/South America.  相似文献   

16.
We propose the new name Rhynchospora galeana to replace the illegitimate later homonym R. breviseta (Gale) Channell. Rhynchospora galeana is a member of section Plumosae. It grows in savannas and pinelands in the southeastern U.S.A. and the Greater Antilles.  相似文献   

17.
Rosellinia necatrix is a soil-borne root pathogen affecting a wide range of commercially important plant species. The mycelium of R. necatrix was transformed to hygromycin B resistance by an Agrobacterium tumefaciens-mediated transformation system using a binary plasmid vector containing the hygromycin B phosphotransferase (hph) gene controlled by the heterologous fungal Aspergillus nidulans P-gpd (glyceraldehyde 3-phosphate dehydrogenase) promoter and the trpC terminator. Co-cultivation of R. necatrix strain W1015 and A. tumefaciens strain AGL-1 at 25°C using the binary vector pAN26-CB1300, which contained the hygromycin B resistance cassette based on pAN26 and pCAMBIA1300, resulted in high frequencies of transformation. The presence of the hph gene in the transformants was detected by PCR, and single-copy integration of the marker gene was demonstrated by Southern b lot analy s is. This report of an Agrobacterium-mediated transformation method should allow the development of T-DNA tagging as a system for insertional mutagenesis in R. necatrix and provide a simple and reliable method for genetic manipulation.  相似文献   

18.
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.  相似文献   

19.
Toxocysts of the genus Pleurotus are blastoconidia-like ovoid structures surrounded by a liquid droplet containing a toxin that paralyzes nematodes. This study investigated toxocyst development using a strain S396 of Pleurotus cystidiosus subsp. abalonus (subgen. Coremiopleurotus). The surface of the liquid droplet was found to be an elastic envelope. When a nematode touches the toxocyst, the envelope adheres to the worm and bursts. Toxocysts are induced simultaneously with coremia formation in the absence of nematodes and developed only from aerial hyphae in which nuclear division had ceased. In the early stage of toxocyst development, liquid springs repeatedly from the tip of the sterigma-like stipe before ovoid (blastoconidium-like structure) formation. A certain substance in the liquid might polymerize to form the envelope while the ovoid simultaneously budded in the droplet. The nucleus tends to locate near the toxocyst, especially in early stage of toxocyst development. Each dikaryotic cell predominantly formed one or two toxocyst(s) while each monokaryotic cell predominantly formed one. In rare cases, a nucleus existed in the toxocyst, suggesting the possibility that the toxocyst is a vestigial blastoconidium.  相似文献   

20.
Haploporus subtrameteus, a rare polypore, is newly reported for Japan. This fungus was known only from three localities in the Russian Far East, Altai Mts., and three in China. The Japanese material was on a dead tree of Padus grayana around Aokigahara-marubi, Mt. Fuji. This article gives detailed morphology based on the Japanese collection and a photo in the natural habitat.  相似文献   

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