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1.
The gall wasp,Trichilogaster sp., was imported from Australia to assess its potential as an agent for the control of the invasive shrub/treeAcacia pycnantha Benth. in South Africa. Host specificity tests indicate safety for release; of 19 tree/shrub species tested, including 16 species closely related toA. pycnantha, galls developed only onA. pycnantha. However, galling intensity remained consistently low on the host plant; only 21–29% of the branches exposed to the wasp were galled during 3 years of rearing. Neither the prolonged presence of males in test cages (someTrichilogaster species are thelytokous) nor the stage of maturity of reproductive buds exposed to oviposition affected the percentage of branches galled. It is not recommended thatTrichilogaster sp. be released before the possibility of insect-plant homeostasis or mis-matching of wasp and host plant populations/strains/subspecies is investigated, especially since galling intensities of 30% were ineffective in reducing seed production of a relatedTrichilogaster species/Acacia association.   相似文献   

2.
An analytical study has been made of gum specimens from Acacia auriculiformis (two specimens), A.holosericea, A.mangium, A.leptostachya and A.pubifolia, which belong to subseries Juliflorae of the Series Phyllodineae. These gums appear to be more proteinaccous, more acidic and more viscous, with higher methoxyl contents and higher molecular weights but with lower proportions of rhamnose and arabinose, than the majority of Acacia gums studied so far.  相似文献   

3.
In Italy, alien acacias have been introduced for ornamental and reforestation purposes, and some species became invasive occupying patches of the Mediterranean landscape. On the Island of Elba (Central Italy), Acacia dealbata and A. pycnantha form dense stands at short distance, showing an impressive massive flowering at the end of the winter/early spring. Our aim was to investigate the behaviour of the two species in relation to the flowering features, from phenology to floral characteristics, and their replay to the observed flower visitors. Differences between the two species emerged on all the parameters considered. A. pycnantha peak of flowering occurred later than A. dealbata and showed larger flower heads (FHs), more flowers/head, stamens/flower and polyads. On A. dealbata, we recorded longer racemes and more FHs/raceme, determining a more flower-dense crown. Even if contacts with flower visitors were generally low on both species, A. dealbata showed a more heterogeneous visitor assemblage. Both acacias species interacted with local generalist pollinators, as bumblebees and honey bees. Flower handling and resource collection strategy by the honey bee indicate a long-term relationship between the bee and the acacias, with bees investing longer time on the larger A. pycnantha flower heads.  相似文献   

4.
Acacia gum exudates are proteinaceous polysaccharides; their protein content ranges from ca 0.2 to 45%.The data presented show that the amino acid compositions of the gums from 12 phyllodinous species (10 from Bentham's sub-series Uninerves racemosae, two from sub-series Juliflorae) also vary considerably, particularly in respect of their hydroxyproline content (55 residues per 1000 residues in A. aestivalis gum, 287 residues per 1000 in A. saliciformis gum). The proportions of some other amino acids, e.g. alanine, aspartic acid, proline and serine also vary considerably, but the proportions of others, e.g. cystine, methionine, histidine, threonine, tyrosine and valine, are remarkably constant. The amino acid composition of gums with a very low protein content (e.g. A. victoriae and A. mycrobotrya) is similar to that for a highly proteinaceous gum (A. tumida). There are, however, considerable differences between the amino acid compositions of the gums from A. saligna and A. pycnantha (South African and Western Australian specimens). This strengthens previous chemotaxonomic evidence, based on the polysaccharide parameters of their gums, that these two species are not as close taxonomically as was originally believed from morphological considerations.  相似文献   

5.
The base of the Furongian Series in the Sino-Korean Block has not been clearly defined due to the lack of the index taxon, Glyptagnostus reticulatus. The Sesong Formation of the Taebaek Group, Taebaeksan Basin, Korea, has been known to range from the Guzhangian Stage of the Cambrian Series 3 to the middle Furongian Series, hence embracing the base of the Furongian Series. Silicified polymerid trilobites were recovered from the middle part of the Sesong Formation. Described are a total of 18 polymerid species of 13 genera: Neodrepanura sp. 1, Teinistion sp. 1, Huzhuia sp. 1, Huzhuia sp. 2, Liostracina simesi, Liostracina sp. 1, Parachangshania monkei, Parachangshania rectangularis nov. sp., Placosema bigranulosum, Fenghuangella laevis nov. sp., Baikadamaspis jikdongensis nov. sp., Baikadamaspis sp. 1, Prochuangia mansuyi, Maladioides coreanicus, Alataspis sesongensis nov. gen., nov. sp., Chuangia sp. 1, and ceratopygids genus and species indeterminate 1 and 2. The stratigraphic occurrence of these trilobites provides a basis for recognition of five zones across the base of the Furongian Series (in ascending order): the Neodrepanura, Liostracina simesi, Fenghuangella laevis, Prochuangia mansuyi, and Chuangia zones. The Neodrepanura and Chuangia zones are provisionally adopted from the previous biostratigraphic scheme, while the three other ones are newly proposed. The recommended base of the Furongian Series in the Taebaek Group of Korea coincides with the base of the Fenghuangella laevis Zone, which appears to represent an episode of profound trilobite faunal turnover.  相似文献   

6.
The genus Ilex to which mate (Ilex paraguariensis) belongs, consists of more than 500 species. A wide range of metabolites including saponins and phenylpropanoids has been reported from Ilex species. However, despite the previous works on the Ilex metabolites, the metabolic similarities between species which can be used for chemotaxonomy of the species are not clear yet. In this study, nuclear magnetic resonance (NMR) spectroscopy-based metabolomics was applied to the classification of 11 South American Ilex species, namely, Ilex argentina, Ilex brasiliensis, Ilex brevicuspis, Ilex dumosa var. dumosa, I. dumosa var. guaranina, Ilex integerrima, Ilex microdonta, I. paraguariensis var. paraguariensis, Ilex pseudobuxus, Ilex taubertiana, and Ilex theezans. 1H NMR combined with principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and hierarchical cluster analysis (HCA) showed a clear separation between species and resulted in four groups based on metabolomic similarities. The signal congestion of 1H NMR spectra was overcome by the implementation of two-dimensional (2D)-J-resolved and heteronuclear single quantum coherence (HSQC). From the results obtained by 1D- and 2D-NMR-based metabolomics it was concluded that species included in group A (I. paraguariensis) were metabolically characterized by a higher amount of xanthines, and phenolics including phenylpropanoids and flavonoids; group B (I. dumosa var. dumosa and I. dumosa var. guaranina) with oleanane type saponins; group C (I. brasiliensis, I. integerrima, I. pseudobuxus and I. theezans) with arbutin and dicaffeoylquinic acids, and group D (I. argentina, I. brevicuspis, I. microdonta and I. taubertiana) with the highest level of ursane-type saponins. Clear metabolomic discrimination of Ilex species and varieties in this study makes the chemotaxonomic classification of Ilex species possible.  相似文献   

7.
The biodiversity of wheat associated bacteria was deciphered from the peninsular zone of India. A total of 264 isolated bacteria were analyzed through amplified ribosomal DNA restriction analysis (ARDRA, using three restriction enzymes Alu I, Msp I and Hae III, which led to the clustering of these isolates into 12–16 groups for the different sites at >75% similarity index, adding up to 70 groups). 16S rRNA gene based phylogenetic analysis, revealed that all the bacteria belonged to three phyla Proteobacteria, Firmicutes, and Actinobacteria of 32 distinct species of 15 genera namely: Achromobacter, Alcaligenes, Arthrobacter, Bacillus, Delftia, Enterobacter, Exiguobacterium, Klebsiella, Methylobacterium, Micrococcus, Paenibacillus, Pseudomonas, Rhodobacter, Salmonella and Staphylococcus. Representative strains from each cluster were screened in vitro for plant growth promoting traits. Among plant growth promoting activities, siderophore producers were highest (15%), when compared to indole acetic acid producers (13%), Zn-solubilizers (11%), P-solubilizers (11%), ammonia (10%), hydrogen cyanide producers (9%), biocontrol (8%), N2-fixers (7%), 1-aminocyclopropane-1-carboxylate deaminase (6%), GA producers (6%) and K-solubilizers (5%). Among 32 representative strains, Alcaligenes faecalis, Arthrobacter sp., Bacillus siamensis, Bacillus subtilis, Delftia acidovorans, Methylobacterium mesophilicum, Methylobacterium sp., Pseudomonas poae, Pseudomonas putida, and Pseudomonas stutzeri exhibited more than six different plant growth promoting activities at high temperature. Thermotolerant bacterial isolates may have application as inoculants for plant growth promotion and biocontrol agents for crops growing at high temperature conditions.  相似文献   

8.
We present low-diversity acritarch assemblages, including Alliumella baltica, Bavlinella faveolata, Brocholaminaria nigrita, Brocholaminaria sp., Eliasum sp., Leiosphaeridia minutissima, Leiosphaeridia spp., Lophosphaeridium sp., Pterospermella solida, Satka colonialica, Siphonophycus sp., and Synsphaeridium sp., as well as filamentous algae and cryptospore-like microfossils recorded from 45 rock samples around the Oryctocephalus indicus Zone (Cambrian Series 3) in the Cambrian Kunzam La (Parahio) Formation at the Kaltarbo locality in the Parahio valley, Northwest Himalaya. One new species Synsphaeridium parahioense was established. The acritarch assemblages at the basal part of the Cambrian Series 3 in the Kunzam La (Parahio) Formation were dependent on the local marine environment. The new discovery of cryptospore-like microfossils from the Cambrian Kunzam La (Parahio) Formation supports the extensive distribution of possible cryptospores in the Cambrian stratigraphic sequences.  相似文献   

9.
10.
Anisakis simplex sensu stricto (s.s.), Anisakis pegreffii, Anisakis berlandi (=A. simplex sp. C), and Anisakis typica are the 4 major species of Anisakis type I larvae. In the Republic of Korea (Korea), A. pegreffii, A. berlandi, and A. typica larvae in fish hosts has seldom been documented. In this study, molecular analysis was performed on Anisakis larvae from the sea eels (Astroconger myriaster), the major source of human anisakiasis in Korea, collected from Tongyeong City, a southern coastal area of Korea. All 20 sea eels examined were infected with Anisakis type I larvae (160 larvae; 8 per fish). Their species were analyzed using PCR-RFLP patterns and nucleotide sequences of internal transcribed spacers (ITS1, 5.8 subunit gene, and ITS2) and mitochondrial cytochrome c oxidase 2 (cox2). Most (86.8%; 112/129) of the Anisakis type I larvae were A. pegreffii, and 7.8% (10/129) were A. typica. The remaining 5.4% (7/129) was not identified. Thus, A. pegreffii is the major species of anisakid larvae in sea eels of the southern coast of Korea.  相似文献   

11.
Chancelloriid sclerites from the lowermost Cambrian Xinji Formation (Series 2, Stage 3), southern margin of the North China platform, are systematically described. Thousands of isolated sclerites from three sections are assigned to three genera and four species, including Chancelloria cf. eros, Allonnia tripodophora, Archiasterella pentactina, and Ar. tetraspina. To accurately document the taxonomic significance of the sclerite structure, modified formulas (m+nC, m+nA, and m+0) are put forward to represent the full series and variation of sclerite forms. Based on the sclerite construction, statistical analysis on the proportions of different sclerite forms in the rock samples and the composition of sclerites in previously described chancelloriid scleritomes, a new scheme for identification and classification of isolated sclerites reconciled within the framework of the complete scleritome, is proposed.  相似文献   

12.
13.
I argue that the idea of ‘quasi-independence’ [Lewontin, R. C. (1978). Adaptation. Scientific American, 239(3), 212–230] cannot be understood without attending to the distinction between fitness and advantageousness [Sober, E. (1993). Philosophy of biology. Boulder: Westview Press]. Natural selection increases the frequency of fitter traits, not necessarily of advantageous ones. A positive correlation between an advantageous trait and a disadvantageous one may prevent the advantageous trait from evolving. The quasi-independence criterion is aimed at specifying the conditions under which advantageous traits will evolve by natural selection in this type of situation. Contrary to what others have argued [Sterelny, K. (1992). Evolutionary explanations of human behavior. Australian Journal of Philosophy, 70(2), 156–172, and Sterelny, K., &; Griffiths, P. (1999). Sex and death. Chicago: University of Chicago Press], these conditions must involve a precise quantitative measure of (a) the extent to which advantageous traits are beneficial, and (b) the degree to which they are correlated with other traits. Driscoll (2004) [Driscoll, C. (2004). Can behaviors be adaptations? Philosophy of Science, 71, 16–35] recognizes the need for such a measure, but I argue that she does not provide the correct formulation. The account of quasi-independence that I offer clarifies this point.  相似文献   

14.
《Palaeoworld》2015,24(4):430-437
A new eocrinoid locality of the Balang Formation (Cambrian Series 2) near Kaili City is reported. The fauna is associated with index trilobites, such as Redlichia (Pteroredlichia) murakamii Resser and Endo in Kobayashi, 1935 and Arthricocephalus chauveaui Bergeron, 1899, that are common in the Balang Biota (Cambrian Series 2) but absent in the younger Kaili Biota (Cambrian Series 3). This new locality contains a new eocrinoid fauna (n = 22) that is different from Guizhoueocrinus yui Zhao, Parsley and Peng, 2007a in bearing a smaller theca, a shorter stalk, and a robust attachment disk; thus, a taxon Globoeocrinus zhaoyuanlongensis n. sp. is proposed.  相似文献   

15.
Vibrio alginolyticus, Vibrio campbellii, and Vibrio harveyi were inhibited by Isochrysis galbana in batch cultures. I. galbana reduced the V. alginolyticus, V. campbellii, and V. harveyi counts to undetectable levels in 2, 4, and 7 days (<0.01 Vibrio spp. mL?1), respectively, remaining so until the end of the experiment on day 15. Other heterotrophic bacteria reached counts of 106 CFU mL?1 on ZoBell medium at the end of the experiment. Vibrio parahaemolyticus was not inhibited by I. galbana. In all mixed I. galbana and Vibrio spp. cultures, the algal density increased from 3.5 to 4.0?×?107 cells mL?1, higher than that in I. galbana cultures alone, indicating a lack of an inhibitory effect on microalgae in the mixed cultures. The predominant fatty acids (>82 %) of I. galbana during the stationary growth phase were estearidonic (24.3 %), oleic (15.7 %), myristic (13.8 %), docosahexaenoic (11.0 %), palmitic (10.3 %), and α-linolenic (7.2 %) acids. These results demonstrate that I. galbana synthesizes antibacterial fatty acids that inhibit the growth of pathogenic bacteria such as V. alginolyticus, V. campbellii, and V. harveyi.  相似文献   

16.
Australian gum specimens from Acacia saliciformis, A. xanthina, A. rostellifera, A. murrayana (two specimens differing in the mode of initiation of gum exudation), A. georginae, A. cyclops, A. implexa, and an un-named species (Maslin ‘P31’) have been analysed. The first four of these are placed within Bentham's Series 1, subseries 6F, A. georginae within subseries 7E, and the remainder within subseries 7F. These data extend considerably the ranges of the analytical parameters reported previously for phyllodine species. The molecular weights of the gums from A. cyclops and A. implexa are much higher than those reported earlier for South African specimens; this may affect some taxonomic deductions based on their examination. The gum composition of A. saligna can no longer be regarded as atypical of a phyllodinous species; a suggestion that A. saligna should be transferred to the section Juliflorae may require reconsideration. The major difference between the specimens of gum from A. murrayana lies in their nitrogenous content. Data are reported for the amino acid compositions of the gums from A. saliciformis and A. xanthina.  相似文献   

17.
Recently, Weston et al. (2004; Wide faces or large canines? The attractive versus the aggressive primate. Proceedings of the Royal Society of London, Series B, 271, 416–419) found that facial width-to-height ratio (WHR) is a sexually dimorphic characteristic in humans; males have higher facial WHR than females. Following this study, Carré et al. (2008; In your face: facial metrics predict aggressive behavior in the laboratory and in varsity and professional hockey players. Proceedings of the Royal Society of London, Series B, 275, 2651–2656) found that individual differences in facial WHR accounted for a significant proportion of the variance in aggressive behavior of men, but not women. I tested these two hypotheses in a sample of 470 Turkish university students. Facial WHR was measured from frontal photographs. I also measured the aggressiveness level of 212 individuals using the Buss and Perry aggressiveness questionnaire. The mean facial WHR (and standard deviation) was 1.89±0.12 for males and 1.91±0.11 for females. There was no relationship between facial WHR and the self-reported aggressive behavior for either sex. The facial WHR is not a sexually dimorphic characteristic (at least) for Turkish people, and it does not appear to be associated with self-reported trait aggression.  相似文献   

18.
Three series of azole piperazine derivatives that mimic dicyclotyrosine (cYY), the natural substrate of the essential Mycobacterium tuberculosis cytochrome P450 CYP121A1, were prepared and evaluated for binding affinity and inhibitory activity (MIC) against M. tuberculosis. Series A replaces one phenol group of cYY with a C3-imidazole moiety, series B includes a keto group on the hydrocarbon chain preceding the series A imidazole, whilst series C explores replacing the keto group of the piperidone ring of cYY with a CH2-imidazole or CH2-triazole moiety to enhance binding interaction with the heme of CYP121A1. The series displayed moderate to weak type II binding affinity for CYP121A1, with the exception of series B 10a, which displayed mixed type I binding. Of the three series, series C imidazole derivatives showed the best, although modest, inhibitory activity against M. tuberculosis (17d MIC?=?12.5?μg/mL, 17a 50?μg/mL). Crystal structures were determined for CYP121A1 bound to series A compounds 6a and 6b that show the imidazole groups positioned directly above the haem iron with binding between the haem iron and imidazole nitrogen of both compounds at a distance of 2.2?Å. A model generated from a 1.5?Å crystal structure of CYP121A1 in complex with compound 10a showed different binding modes in agreement with the heterogeneous binding observed. Although the crystal structures of 6a and 6b would indicate binding with CYP121A1, the binding assays themselves did not allow confirmation of CYP121A1 as the target.  相似文献   

19.
The species from the order Neisseriales are currently distinguished from other bacteria on the basis of branching in 16S rRNA gene trees. For this order containing a single family, Neisseriaceae, no distinctive molecular, biochemical, or phenotypic characters are presently known. We report here detailed phylogenetic and comparative analyses on the 27 genome sequenced species of the order Neisseriales. Our comparative genomic analyses have identified 54 conserved signature indels (CSIs) in widely distributed proteins that are specific for either all of the sequenced Neisseriales species or a number of clades within this order that are also supported by phylogenetic analyses. Of these CSIs, 11 are specifically present in all of the sequenced species from this order, but are not found in homologous proteins from any other bacteria. These CSIs provide novel molecular markers specific for, and delimiting, this order. Twenty-one CSIs in diverse proteins are specific for a group comprised of the genera Neisseria, Eikenella, Kingella, and Simonsiella (Clade I), which are obligate host-associated organisms, lacking flagella and exhibiting varied morphology. The species from these genera also formed a strongly supported clade in phylogenetic trees based upon concatenated protein sequences; a monophyletic grouping of these genera and other genera displaying similar morphological characteristics was also observed in the 16S rRNA gene tree. A second clade (Clade II), supported by seven of the identified CSIs and phylogenetic trees based upon concatenated protein sequences, grouped together species from the genera Chromobacterium, Laribacter, and Pseudogulbenkiania that are rod-shaped bacteria, which display flagella-based motility and are capable of free living. The remainder of the CSIs were uniquely shared by smaller groups within these two main clades. Our analyses also provide novel insights into the evolutionary history of the Neisseriales and suggest that the CSIs that are specific for the Clade I species may play an important role in the evolution of obligate host-association within this order. On the basis of phylogenetic analysis, the identified CSIs, and conserved phenotypic characteristics of different Neisseriales genera, we propose a division of this order into two families: an emended family Neisseriaceae (corresponding to Clade I) containing the genera Alysiella, Bergeriella, Conchiformibius, Eikenella, Kingella, Neisseria, Simonsiella, Stenoxybacter, Uruburuella and Vitreoscilla and a new family, Chromobacteriaceae fam. nov., harboring the remainder of the genera from this order (viz. Andreprevotia, Aquaspirillum, Aquitalea, Chitinibacter, Chitinilyticum, Chitiniphilus, Chromobacterium, Deefgea, Formivibrio, Gulbenkiania, Iodobacter, Jeongeupia, Laribacter, Leeia, Microvirgula, Paludibacterium, Pseudogulbenkiania, Silvimonas, and Vogesella).  相似文献   

20.
Previously, we reported isolation and characterization of mutacin III and genetic analysis of mutacin III biosynthesis genes from the group III strain of Streptococcus mutans, UA787 (F. Qi, P. Chen, and P. W. Caufield, Appl. Environ. Microbiol. 65:3880–3887, 1999). During the same process of isolating the mutacin III structural gene, we also cloned the structural gene for mutacin I. In this report, we present purification and biochemical characterization of mutacin I from the group I strain CH43 and compare mutacin I and mutacin III biosynthesis genes. The mutacin I biosynthesis gene locus consists of 14 genes in the order mutR, -A, -A′, -B, -C, -D, -P, -T, -F, -E, -G, orfX, orfY, orfZ. mutA is the structural gene for mutacin I, while mutA′ is not required for mutacin I activity. DNA and protein sequence analysis revealed that mutacins I and III are homologous to each other, possibly arising from a common ancestor. The mature mutacin I is 24 amino acids in size and has a molecular mass of 2,364 Da. Ethanethiol modification and peptide sequencing of mutacin I revealed that it contains six dehydrated serines, four of which are probably involved with thioether bridge formation. Comparison of the primary sequence of mutacin I with that of mutacin III and epidermin suggests that mutacin I likely has the same bridging pattern as epidermin.  相似文献   

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