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1.
A new species and genus of Microcoryphia is described as a result of the detailed comparison of specimens from Italy and Spain which had been initially identified as Praemachilis excelsior. The new genus, named Mendeschilis has as its most important distinctive taxonomic characteristic the presence, in the male, of parameres in the VIIIth and IXth urosternites, while Praemachilis (from Italy) has only one pair of parameres in the IXth urosternite. Other anatomical characteristics which allow us to differentiate the new genus and the new species are described.  相似文献   

2.
Two fossil silverfish preserved in Burmese amber (dated from the Cretaceous: Upper Albian, 100–110 MY) are described in the new genus and species Burmalepisma cretacicum (Lepismatidae: Lepismatinae). The fossil species is characterized mainly by its chaetotaxy.  相似文献   

3.
Praemachiloides iberica n. sp. is described and compared with the other four known species of the genus: P. janetschecki, P. insularis, P.tarsispina and P. autumnalis. The main difference of P. iberica n. sp. from the other known congenerics is the presence, in the male, of a field of plaited setae on the ventral surface of the maxillary palp.  相似文献   

4.
In 1999, natural populations of Dactylis glomerata L., Festuca arundinacea Schreb., Phalaris tuberosa L. and the macrotherm species Brachypodium rupestre (Host) R. et S., were collected as seed in Southern Italy (Apulia, Basilicata and Campania regions) to evaluate the potential as forage of native germplasm under dry conditions, using available commercial cultivars as controls. The persistence of accessions, biometric, phenologic, productive and qualitative parameters of forage have been studied for a 3-year period (2000–2002) in a typical Mediterranean environment. D. glomerata is widely present in the studied area with two subspecies (subsp. glomerata L., subsp. hispanica (Roth) Nyman). The research pointed out significant differences in plant size, earliness and single plant dry matter (DM) production. All the natural ecotypes belonging to this species showed higher persistence than the control cultivars. Some natural ecotypes appeared to have potential for improving DM yield (subsp. glomerata ecotypes) and reducing neutral detergent fibre (NDF) content (subsp. hispanica ecotypes). Natural ecotypes belonging to F. arundinacea, P. tuberosa, and B. rupestre are sporadically present in the studied area. Among them, two ecotypes of P. tuberosa, showing higher winter growth and earliness compared to cv. ‘Holdfast’, seem to be interesting for a future breeding programme.  相似文献   

5.
Calamintha nepeta and Micromeria thymifolia have been traditionally used in the Mediterranean area as condiments and medicinal plants for a long time. Whereas in parts of Italy C. nepeta (special recipes have been developed in Lazio and Tuscany) is also an established garden plant showing different evolutionary products and their interaction among each other and the wild progenitor, M. thymifolia is being developed into a new crop plant. Both plants and their uses are described with regard to Italy. There is a marked tendency to broaden the use of condiments and spices which results in new crop plants which have to be documented and elaborated in further studies. Many species of Labiatae are predisposed to use by man and new items can be found even in areas which have to be considered as well studied.  相似文献   

6.
Samples of thysanurans (orders Microcoryphia and Zygentoma) collected in the Azores were studied. The known distributions in the archipelago of Parapetrobius azoricus, Dilta saxicola, Lepisma saccharina and Ctenolepisma longicaudata are substantially enlarged. Machilinus cf. rupestris gallicus as well as the genus Machilinus and the family Meinertellidae are reported for the first time in the Azores. Trigoniophthalmus borgesi sp.n. (Microcoryphia: Machilidae), is described from the laurisilva forest of the Terceira island.  相似文献   

7.
8.
Altamurano is a linseed landrace of southern Italy. Its area of origin is characterised by typical Mediterranean climate. Traditionally, Altamurano is spring sown, and mainly used as a feed integrator for animals. This landrace was evaluated during 2 years within varietal (16 modern varieties) and sowing date (15 sowings, from October to April, with ‘Antares’ as a control) trials. Growth analysis was carried out on two sowings. Seed yield was slightly lower than modern varieties, with advantages in late sowings. Reproductive efficiency, mean seed weight, harvest index and oil percentage were often higher than in modern cultivars. Altamurano was also characterised by early flowering, low vegetative growth, long leaf area duration, high light use efficiency during early grain filling phase, and relatively long grain filling period. All these features are connected with its adaptation to spring sowings in Mediterranean areas, characterised by early spring drought. Despite the decrease of its cultivation area from about 400 to less than 100 ha in the last 10 years, Altamurano is still present in the more traditional farms of the area as a heritage of past growing systems and historical adaptation to the environment.  相似文献   

9.
The collembological composition of samples from the Central and Western Pyrenees (Northern Spain) was studied. Soils from two biotopes (pine forest and Rhododendron shrub) were studied in Nuria and Vallibierna, using different diversity indices and multivariate analyses. Ten species were found that were endemic to the Iberian Peninsula. Three of these are exclusive to the Pyrenees: Ceratophysella elegans, Hypogastrura dasiensis and Protachorutes pyrenaeus. The greatest diversity was observed in the soils of Rhododendron, above all at Nuria. Collembola were most poorly represented in the pine forest of Vallibierna, where the endemic Hypogastrura meridionalis was the dominant species. Multivariate analyses indicated that the latter species characterizes this pine forest and separates it from all other biotopes studied. The evenness (E) was most pronounced in Nuria, where Folsomia manolachei was the characteristic species.  相似文献   

10.
Material from the organic layer of a podsol soil in a spruce stand in southern Norway was incubated for 21/2 years at 15°C in microcosms with a volume of 0.1 dm3. The soil was sterilised and reinoculated with a mixed microflora before the incubation start, and given three different faunal communities: (1) A mixed assemblage of microarthropods plus the enchytraeid Cognettia sphagnetorum (“full fauna”, FF), (2) only C. sphagnetorum (“enchytraeids”, E), and (3) no animals added (“no fauna”, NF). The respiration rate was measured during the last 14 months of incubation, and was highest in FF throughout this period. When all respiration analyses were pooled, the value for FF was 33% higher than for NF and 25% higher than for E. The substrate dry mass loss, measured twice, was also highest in FF (17% higher in FF than in both the other treatments after 11/2 years of incubation, and 31% higher than in both the other treatments after 21/2 years). Both for respiration and for mass loss, the difference between FF and the other two treatments was statistically significant, while there was no apparent difference between the E and NF treatments. There was no sign of a general rise or fall in the respiration rate during the 14 months from the first to the last analysis. The ammonium (and total N) concentration in the soil water was higher in FF and E than in NF, whereas the nitrate concentration was lowest in FF and highest in E. The higher mineralisation activity in the FF treatment was probably caused by the higher diversity of mesofauna, and perhaps also by higher diversities of microflora and microfauna accidentally introduced together with the arthropods.  相似文献   

11.
Summary Laboratory microcosms were used to study microbial populations and biomasses developing in fragmented litter of Pinus nigra Arnold var. nigra (A. et G.). Direct observations (fungal standing crop and fluorescein-stainable mycelia), litter enzyme analyses (cellulase and dehydrogenase), and measurements by physiological methods (microbial CO2 production and total microbial, fungal, and bacterial viable biomasses) were made at 3-week intervals for 15 weeks. Most variables showed great changes during this period, which were ascribed to a rise in litter moisture content during the initial phase of the experiment, and to substrate depletion towards its final phase. The addition of the collembolan Tomocerus minor (Lubbock) for 1 week enhanced cellulase activities by 4%. When the animals were introduced after 6 weeks, the fungal standing crop was enhanced, and the percentage of fluorescein-stainable mycelia was reduced. Dehydrogenase activity was increased by grazing when the microbial population had been established for 9 weeks or longer. Eucaryotic and procaryotic substrate-induced respiration were positively correlated, which was explained by partial segregation of resources for the two groups. Litter cellulase and dehydrogenase activity showed correlations by other techniques, indicating their suitability as parameters for microbial activity in general, and for the collembolan grazing impact on microbial activity in particular.  相似文献   

12.
We investigated roost selection by Barbastella barbastellus in a mountainous area of central Italy. Twenty-five bats, mostly lactating females, were radio-tracked to 33 roost trees. Trees in unmanaged woodland were favoured as roost trees; woodland subject to limited logging was used in proportion to availability, and areas where open woodland and pasture occurred were avoided. Selection depended on tree condition (dead beech trees were preferred) and height (roost trees were taller than random ones). Cavity selection was based on cavity type, height and entrance direction: roost cavities were mainly beneath loose bark, at a greater height above ground and facing south more frequently than random cavities. Untouched areas of mature woodland should be preserved to provide roosting conditions for B. barbastellus. In logged areas, harvesting protocols should save dead and mature trees; frequent roost switching and small colony size imply that large numbers of roost trees are needed.  相似文献   

13.
We investigated the diversity of rhizobia isolated from different indigenous legumes in Flanders (Belgium). A total of 3810 bacterial strains were analysed originating from 43 plant species. Based on rep-PCR clustering, 16S rRNA gene and recA gene sequence analysis, these isolates belonged to Bradyrhizobium, Ensifer (Sinorhizobium), Mesorhizobium and Rhizobium. Of the genera encountered, Rhizobium was the most abundant (62%) and especially the species Rhizobiumleguminosarum, followed by Ensifer (19%), Bradyrhizobium (14%) and finally Mesorhizobium (5%). For two rep-clusters only low similarity values with other genera were found for both the 16S rRNA and recA genes, suggesting that these may represent a new genus with close relationship to Rhodopseudomonas and Bradyrhizobium. Primers for the symbiotic genes nodC and nifH were optimized and a phylogenetic sequence analysis revealed the presence of different symbiovars including genistearum, glycinearum, loti, meliloti, officinalis, trifolii and viciae. Moreover, three new nodC types were assigned to strains originating from Ononis, Robinia and Wisteria, respectively. Discriminant and MANOVA analysis confirmed the correlation of symbiosis genes with certain bacterial genera and less with the host plant. Multiple symbiovars can be present within the same host plant, suggesting the promiscuity of these plants. Moreover, the ecoregion did not contribute to the separation of the bacterial endosymbionts. Our results reveal a large diversity of rhizobia associated with indigenous legumes in Flanders. Most of the legumes harboured more than one rhizobial endosymbiont in their root nodules indicating the importance of including sufficient isolates per plant in diversity studies.  相似文献   

14.
The effects of bacterial inoculants on the growth of winter wheat were studied in a growth chamber. Azospirillum brasilense, Azotobacter chroococcum, Bacillus polymyxa, Enterobacter cloacae, or a mixture of the four rhizobacteria were the inoculants tested. Inoculation effects on yield, yield components, and N-derived from fertilizer (Ndff) were assessed. The response of plants inoculated with individual bacteria was inconsistent and varied with treatment. At the first harvest (58 days after planting-DAP) plants inoculated with the mixture exhibited increases in plant dry weight, total-N and Ndff. At the second harvest (105 DAP), plants inoculated with A. brasilense and the mixture exhibited increases in shoot biomass, whereas at maturity (170 DAP), the inoculated plants showed no differences in total-N or shoot dry matter yield, as compared to the uninoculated controls. Inoculation with A. brasilense, however, increased the Ndff in the shoots, and B. polymyxa tended to enhance grain yield. Practical use of these rhizobacteria as inoculants for winter wheat may have limited value until such time as we better understand factors which influence rhizosphere competence of bacterial inoculants.  相似文献   

15.
In order to evaluate the genetic diversity in Lathyrus genus, the Inter Simple Sequence Repeats method (ISSR) was exploited in five populations. These consisted of two cultivated species belonging to section Lathyrus (L. sativus L. and L. cicera L.) and a wild one belonging to the section Clymenum (L. ochrus DC.). Two 3′anchored ISSR primers and two unanchored ones, generated a total of 60 useful polymorphic DNA bands. Our data provide evidence of high molecular polymorphism at the intra- and the inter-specific levels showing that both wild and cultivated forms constitute an important pool of diversity. Moreover, among the generated DNA bands, a 500 bp band, totally absent in the banding patterns of the section Clymenum, appears to be a molecular marker of section Lathyrus. Results provided for lineage and suggest recent origin of these species that might have evolved from a common ancestor producing both L. ochrus species and the two other species L. sativus and L. cicera. These relationships support previous studies based on morphological variation and molecular analysis.  相似文献   

16.
Measuring a species decline is pivotal to evaluate their conservation status, but an accurate assessment of demographic trends requires observations collected across broad spatial and temporal scales. Volunteers can help to collect information over large scales, but their data may be affected by heterogeneity for sampling efforts and protocols, which may influence detection probability. Ignoring this issue may conduct to misleading conclusions. Here we show that data collected by different volunteer groups can be integrated with measures of sampling efforts, to obtain information on large scale demographic trends. We collected data on 33 common toad (Bufo bufo) populations across Italy for the period 1993–2010. We used two approaches (meta-analysis; analysis of average change in population size) to evaluate the overall demographic trend. We incorporated measures of volunteer sampling efforts into analyses, to take into account changes in detection probability. Toad abundance significantly declined in the last decade. From 2000 to 2010, 70% of populations showed a strong decline, and only 10% increased. Trends were heterogeneous among populations, but taking into account sampling effort reduced heterogeneity by 40%. We detected a 76% cumulative average decline of toad populations, despite an increasing mean sampling effort. The widespread toad decline rises concern for its future, also because the causes remain unclear. Volunteer data can be extremely useful to identify large scale population trends, if information on sampling effort are recorded and used to adjust counts.  相似文献   

17.
The Abruzzo region (Central Italy) shows peculiar characteristics: the extension of mountain territory is the highest in mainland Italy and the whole region is less developed as compared to other Central Italy areas. Moreover, the farming systems developed with specific peculiarities parallel to shepherdy. Recently, in the area of the Gole di Popoli, ideally constituting the door of the inner and less developed part of the region, four populations of common bean were collected. Seed morphological traits, phaseolin and lectin profiles were analysed. Three populations appeared heterogeneous in phaseolin and lectin fractions. C, T, and S phaseolin types, C type being predominant, and six lectin patterns were observed. A comparison with common bean populations from the Basilicata region (Southern Italy) showed interesting differences between the two regions. The present contribution, besides the limitation due to the small number of samples, suggests that the Abruzzo, and other Italian regions with similar agro-environmental conditions, might retain highly interesting local populations.  相似文献   

18.
Sixty-two accessions of Prosopis cineraria, collected from different areas of the Cholistan desert and from the vicinity of Islamia University, Bahawalpur during June, 2002 were evaluated for agro-morphological diversity. Data collected revealed considerable variation for pod length, pod thickness, number of seeds per pod, pod weight, 100-seed weight, seed size, number of pinnules, length of pinnae, length of the pinnulae, and breadth of the pinnulae. Accessions GD-1 and GD-2, collected from Gadhen Wala Toba, KWT-1, KWT-3, KWT-4, KWT-6, from Khokhran Wala Toba, TWT-2, TWT-7, TWT-8, from Taraway Wala Toba, CSW-2, CSW-7, CSW-8, from Chah Sulleh Wala, and IUB-5, IUB-9, from Islamia University, Bahawalpur, showed very high variation. Overall, accessions KWT-6 from Khokhran Wala Toba, and TWT-7, from Taraway Wala Toba, (both from Cholistan desert), appeared as best genotypes based on their morphological variation detected in this study.  相似文献   

19.
Dendrobaena octaedra (Lumbricidae) and Cognettia sphagnetorum (Enchytraeidae) are the two most dominating soil invertebrates in terms of biomass in boreal coniferous forest soils. A microcosm experiment was set up in order to study the influence of pH, moisture and resource addition on D. octaedra and C. sphagnetorum when both species are simultaneously present. Two kinds of coniferous forest humus were used as substrate, pine stand humus (pH 4.2), and spruce stand humus (pH 4.6); in the third treatment the pine stand humus was adjusted with slaked lime (CaOH2) to the same initial pH as the spruce stand humus. Each substrate was adjusted to water contents of 25%, 42.5% and 60% of WHC (referred to as ‘dry’, ‘moist’ and ‘wet’). In the second part of the experiment, spruce needle litter and birch leaf litter were separately added into the pine stand humus (‘moist’, unlimed) and compared with a control without litter. The microcosms were plastic jars with 75 g (d.m.) of humus, into which 4 specimens of D. octaedra and 70 specimens of C. sphagnetorum were added. D. octaedra showed the highest biomass and C. sphagnetorum the lowest biomass in the spruce stand humus with higher pH. Moisture did not affect earthworms, while C. sphagnetorum thrived best at the highest moisture. Addition of both kinds of litter increased the numbers and biomass of D. octaedra, while on C. sphagnetorum resource addition had little effect. The results help to explain the abundance of these two species in coniferous forests differing in soil acidity, moisture and fertility.  相似文献   

20.
Summary The soil mite Erythraeus ghilarovi n.sp. is described with regard to its intraspecific morphological variation. The specimens were collected in the Andes of southern Peru, at an altitude of about 4700 m (puna grass region).Decicated to the late Prof. Dr. M.S. Ghilarov  相似文献   

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