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1.
Biochemical levels of serum proteins and enzymes were investigated in two populations of the baboons Papio anubis and P. cynocephalus. The mean average levels of proteins or enzyme activity are the same in the two species. The only difference concerns the level of an inhibitor of pseudocholinesterase in a few individuals of Papio anubis.  相似文献   

2.
Free amino acids concentrations were determined in the abdominal muscle of Palaemon serratus and P. squilla submitted to several temperatures. Only serine, alanine and proline show significant differences between the two species. Temperature variations mainly affect glycine, but do not act in a similar manner on all other amino acids. Differences in the influence of temperature upon the total free amino acids of P. serratus and P. squilla can be related with their migratory behaviour.  相似文献   

3.
陈静  武丙琳  鲁庆彬 《生态学杂志》2016,27(11):3719-3726
动物个体行为的生态效应主要反映在它们的活动节律和时间分配上.2012年11月至2013年10月,在杭州野生动物园,用瞬时扫描取样法对1群圈养阿拉伯狒狒的日活动节律和活动时间分配进行了调查研究.结果表明: 1)在活动时间分配中,主要活动(频次百分率≥5%)包括休息(42.5%)、游动(16.2%)、玩耍(10.0%)、摄食(9.8%)、理毛(9.4%)和观望(7.3%);频次百分率低于5%的称为次要活动,共4.8%.2)阿拉伯狒狒的活动时间分配具有明显的季节性变化,冬季摄食和观望时间增加,玩耍和理毛时间减少,但休息和游动行为没有显著季节差异.3)阿拉伯狒狒通常在上午和下午分别出现摄食高峰,并随着气温逐渐转冷,摄食活动逐渐增加,出现3个摄食高峰;这可能是动物在寒冷季节为抵御寒冷而采取的补充能量的一种策略.4)在温暖季节,阿拉伯狒狒只有中午一个休息高峰和一个理毛高峰,更多时间用于游动和玩耍,表现为多峰特征;在寒冷的冬季,休息行为也体现了多峰特征,但其游动、玩耍和张望时间节律并不与温暖季节有明显差异.因此,杭州地区圈养阿拉伯狒狒的冬季日活动节律与许多灵长类(如黑冠长臂猿、维氏冕狐猴和绒毛猴等)不一样,采取摄食增加能量,而非休息减少能量消耗的策略.总之,阿拉伯狒狒的行为体现出明显的节律性,且其活动节律具有季节性差异,这些可能是阿拉伯狒狒适应于圈养环境特有的食物资源和温度变化的影响而形成的.  相似文献   

4.
The corticioid basidiomycete Peniophorella praetermissa has long been regarded as a morphologically variable species complex. An ITS-based phylogenetic study based on a worldwide sampling was carried out using parsimony and Bayesian inference. The resulting trees feature three major clades, further divided into well-supported subclades. These could be considered as distinct species, a contention that is further supported by crossing test data. Only two out of the eight phylogenetic lineages identified can be distinctly morphologically characterized: P. odontiaeformis and P. subpraetermissa. P. odontiaeformis is an odontioid species with a paleotropical distribution whereas the taxa in the remaining subclades have smooth basidiomata and are distributed in temperate areas. P. subpraetermissa is known only from the type collection and is distinguished microscopically by its reddish brown apically encrustated cystidia. Taxa in the remaining subclades are impossible to distinguish from each other morphologically, and therefore, are viewed as a species complex, P. praetermissa s. lat. One of the subclades, which is widely distributed but restricted to the Northern hemisphere, is proposed to represent P. praetermissa s. str. An epitype is selected from the same area as the holotype, among the specimens studied here. However, the geographically most widespread clade with many representatives from both hemispheres is here referred to as P. pertenuis, a taxon that was previously considered a synonym to P. praetermissa.  相似文献   

5.
6.
The diatom genus Pseudo-nitzschia contains a number of toxic and non-toxic species that are difficult to distinguish using light microscopy (LM) and at times even with electron microscopy (EM). In order to investigate the actual diversity and seasonal occurrence of Pseudo-nitzschia species, we developed genus-specific ribosomal DNA LSU primers to be used in PCR reactions with environmental DNA samples. Using this approach, we constructed clone libraries from samples collected in the Gulf of Naples (Mediterranean Sea) on six dates between April and October 2004 and compared molecular results with those obtained from counts using LM on the same dates. Thirteen distinct genotypes could be distinguished by their LSU sequence, against five species discriminated using the light microscope. Despite the limited number of samples, 10 out of 14 LSU genotypes known in the area were recovered. In addition, three new genotypes were retrieved, two of which were from within the P. galaxiae clade and one possibly corresponding to an undescribed P. delicatissima-like morph. Molecular results matched LM findings in the case of P. multistriata, whereas they provided a much higher resolution for morphs such as P. delicatissima- and P. pseudodelicatissima-like, which include several pseudo-cryptic species. Overall, the direct amplification with the primers developed proved to be an effective and useful tool to assess Pseudo-nitzschia diversity in the natural environment.  相似文献   

7.
When the genus Paravahlkampfia was distinguished from the genus Vahlkampfia on the basis of significant differences in small subunit ribosomal DNA sequences, Paravahlkampfia ustiana was the only described species of this new genus. More recently, a vahlkampfiid strain has been isolated (from soil from an upland farm in Scotland) which has trophozoite and cyst morphology more similar to P. ustiana than to other non-flagellating vahlkampfiid species. Also, it clusters with P. ustiana in phylogenetic trees derived from 5.8S ribosomal DNA sequences. However, it is significantly different from P. ustiana in both phenotype and internal transcribed spacer sequence. Consequently, a new species, Paravahlkampfia lenta, is proposed.  相似文献   

8.
The Phrynichus deflersi species group is a well-defined group inhabiting the Arabian deserts and adjacent areas. The relationship of this group to other species of Phrynichus (the P. ceylonicus group) is obscure. The study of mating behaviour and spermatophore morphology of a member of the Phrynichus deflersi species group allows comparison with other species of Phrynichus and with Euphrynichus and evidence concerning the interrelationships of these three groups. Features of morphology, mating behaviour and spermatophore morphology of Phrynichus dhofarensis suggest that the P. deflersi species group and the P. ceylonicus species group are sister groups and that both (the genus Phrynichus) comprise the sister group of Euphrynichus. This conclusion remains tentative given that only two members of the P. ceylonicus species group and one of the P. deflersi species group have been studied. Mating success is quite variable, suggesting sexual selection.  相似文献   

9.
Development of Schistosoma bovis from Spain in different species or genus of intermediate hosts (Bulinus truncatus, B. wrighti and Planorbarius metidjensis) modifies cercarial productivity and its dynamics. From B. truncatus to B. wrighti and to P. metidjensis, cercarial productivity decreases while the length of the production period is increased. Variations in the dynamics are less obvious between the two species of Bulinus than between Bulinus spp. and P. metidjensis. In the latter the emission pattern is characterized by a 45–48-day production rhythm. These differences are explained in terms of larval demographic strategies and biotic capacities of the hosts. The validity of employing cercarial production as an indicator of host-parasite compatibility is discussed.  相似文献   

10.
Peat-bog pine Pinus uliginosa Neumann has become extinct or rare in many parts of Europe. It is supposed to hybridize with P. sylvestris but the influence of hybridization to genetic erosion of the P. uliginosa gene pool is unknown. In the presented study, the crossability between P. uliginosa and P. sylvestris was analyzed in a sympatric population at Węgliniec reserve in Poland. The aim of the study was to prove natural hybridisation and to estimate the influence of this phenomenon on possible natural gene pool erosion of peat-bog pine. A sequence polymorphism in the trnF–trnL cpDNA region of P. uliginosa and P. sylvestris was used to develop the species diagnostic PCR-RFLP marker. The marker of paternally transmitted cpDNA was applied in haplotype analyses of the progeny from open-pollinated P. uliginosa seeds (collected in 2000–2002) and from P. sylvestris ones (in 2002). An inconsistency in species diagnostic cpDNA haplotypes of seedlings and parental trees was observable both for P. uliginosa and P. sylvestris (about 1% and 2% of hybrids seeds, respectively). The results prove the occurrence of reciprocal hybridisation between the species. The influence of hybridisation on the natural gene pool protection and measures to reintroduce peat-bog pine is discussed.  相似文献   

11.
Morphological, chemical, cytological and genetic evidence demonstrating the absence of taxonomic distinction between Piper methysticum and Piper wichmannii are reviewed. Piper methysticum is not a separate species, but rather a group of sterile cultivars selected from somatic mutants of P. wichmannii. As P. methysticum was described first (1786), it has priority and P. wichmannii (1910) is superfluous. A new subspecific classification is suggested that makes a distinction between the sterile cultivars (P. methysticum var. methysticum) and the wild populations (P. methysticum var. Wichmannii).  相似文献   

12.
The population dynamics of Pseudo-nitzschia species from the Quoddy Region of the Bay of Fundy was examined in a field-based study. Five stations were sampled over a period of 11 weeks during the course of one discrete bloom episode in 2003 with seven species of Pseudo-nitzschia found and enumerated: P. americana, P. delicatissima, P. pseudodelicatissima, P. fraudulenta, P. pungens, P. seriata and P. subpacifica. We related species abundance to physical and chemical properties of seawater (transparency, fluorescence, silicate, phosphate, nitrite + nitrate, ammonia, nitrite, oxygen, sigma-t, tidal level, tidal state and total depth of water column) using canonical correspondence analysis (CCA) to identify factors explaining the greatest amount of variance in their temporal and spatial distribution patterns. Our results indicate that abundance of species and groups of species correlated well with certain specific chemical and physical properties of seawater. P. pseudodelicatissima and P. delicatissima abundance was positively correlated with nitrates and P. americana with depth of the water column. P. pungens was more abundant in samples with higher concentrations of phosphates and lower concentrations of nitrates. P. seriata abundance was negatively associated with total fluorescence. P. subpacifica and P. fraudulenta abundances were not statistically related to any of the variables examined. Our data therefore provides direction for testable, hypothesis driven experiments that could provide predictive insights into the occurrence of certain harmful algal bloom (HAB) species should specific environmental variables be further affected along the gradients extracted in this study.  相似文献   

13.
Flavonoid distribution and populational composition at the collection sites of several samples of Populus acuminata strongly suggest that this taxon is an inter-sectional hybrid between P. angustifolia, sect. Tacamahaca and any one of two or three different species of the section Aigeiros, when the entire range is considered. In the vicinity of the type locality, the Aigeiros parent is P. sargentii. Within any population, foliage of trees of P. acuminata is characterized by morphological intermediacy and an essentially additive flavonoid profile, as compared to the two parental taxa present. In habit the trees resemble those of P. sargentii, and habitats at the collection sites were found to be somewhat intermediate. Fifteen flavonoid compounds were consistently present in samples of the putative hybrid. Twelve of these had diagnostic value because they were absent in one of the parental species. One compound, apigenin 7-O-diglucoside, was found only in P. acuminata. In part, our identifications correspond to compounds reported by Crawford in a morphological and chemical study of P. acuminiata.  相似文献   

14.
The genus Psiadia Jacq. represents the most important indigenous genus, by the number of species present, in the Mascarene archipelago (Mauritius, Reunion, Rodrigues), and is a typical example of adaptive radiation in oceanic islands. The Mauritius species are used in traditional pharmacopoeia for their expectorant properties, and most of them are heavily threatened. Molecular genetic relationships between representatives of eight endangered endemic Psiadia species from Mauritius, conserved in Le Mondrain Reserve, and P. dentata (Cass.) DC, endemic from Reunion island, were studied. The absence of length variations of the 5s rDNA non-transcribed spacer demonstrated the recent common origin of all the species surveyed. RAPD analysis revealed a relatively high intra-specific variability in accordance with the outcrossing mode of reproduction of Psiadia species. Moreover, RAPD analysis showed the existence of four major phenetic groups: (A) P. arguta (Pers.) Voigt, P. dentata, (B) P. penninervia D. C., P. terebinthina A.J. Scott, P. lithospermifolia (Lam.) Cordem, (C) P. viscosa (Lam.) A.J. Scott, P. canescens A.J. Scott, P. cataractae A.J. Scott, and (D) P. pollicina A.J. Scott. These groups were consistent with the chemical composition of the essential oils of the species as well as with their floral characteristics, based on literature. A molecular germplasm database for Psiadia species was established, which will allow further characterisation of new samples being introduced in Le Mondrain Reserve for conservation purpose.  相似文献   

15.
Stearidonic acid (18:4ω3), which is reported to be of rare occurrence in the plant kingdom and which is of considerable dietary and pharmaceutical interest has been found in three closely related Primula species. It occurs, together with γ-linolenic acid (3–4% of the seed oil total fatty acids), in significant percentages in Primula florindae (11%), P. sikkimensis (14%) and P. alpicola (14%). 18:4(ω3 may also be of chemotaxonomic interest in the genus Primula, as high levels may be typical for section Sikkimensis. The only commercial plant source of stearidonic acid known so far is the seed oil of Ribes nigrum.  相似文献   

16.
Females of the vector of Leishmania aethiopica, Phlebotomus pedifer, have previously been morphologically indistinguishable from the non-vector, P. elegonensis. The present studies have biochemically separated these two species. Differences were observed in the mobility of four enzymes, GPI, HK, ICD and PGM on thin-layer starch gel electrophoresis. Using the isoelectric focusing technique, the two species could be differentiated by one enzyme, GPI.  相似文献   

17.
18.
为了测定七星瓢虫成虫对枸杞木虱4种虫态的捕食作用,分别在室内测定七星瓢虫的捕食功能反应、种内干扰、自身密度干扰、捕食偏好性以及在田间七星瓢虫对枸杞木虱的捕食效果.结果表明: 七星瓢虫对枸杞木虱的捕食功能反应符合Holling Ⅱ型方程,其中对卵的最大捕食量为112.6粒,对1~2龄若虫、3~5龄若虫、成虫的最大捕食量分别为536、415和113.9头;田间罩笼试验结果证明,七星瓢虫成虫在其生长周期30 d内能使枸杞木虱总虫口密度下降80.1%;七星瓢虫对1~2龄枸杞木虱若虫的搜寻效率参数a=0.9451,处理时间参数Th=0.001865,整体优于卵、3~5龄若虫与成虫,且在每皿100头的猎物密度下七星瓢虫的最大捕食率能达80.2%,益害比参考值为1∶100.七星瓢虫对枸杞木虱的捕食作用受自身密度的影响显著大于种内干扰.在混合猎物密度为每皿100头下,七星瓢虫更偏好木虱成虫,在密度为每皿300头下,七星瓢虫更偏向于木虱若虫.表明七星瓢虫是很有控制潜力的捕食性天敌,人工释放七星瓢虫成虫可有效取食枸杞木虱初孵若虫,降低木虱为害.  相似文献   

19.
The normal-alkane range in leaf cuticular waxes from 22 Persea species and cultivars and from the closely related genus Beilschmiedia was C23 H48 to C35, H72; alkanes with an odd number of carbon atoms predominated, C33 H68 usually constituting about half of the total wax. The alkane profiles gave good agreement with established taxonomy. Beilschmiedia showed an alkane distribution quite different from that of the Persea taxa. Amongst Persea species, the geographical and phylogenetic distinctiveness of P. indica and P. donnell-smithii were reflected in the distinctiveness of their alkanes. Within the subgenus Persea. the morphologically most distinct entity. P. schiedeana, also had a distinct alkane profile. Cultivars of hybrid origin indicated in their alkane proportions pronounced gene interaction.  相似文献   

20.
The patterns of five multilocus isozyme systems were investigated in seed, shoot and cotyledon tissue of two species of mesquite, Prosopis glandulosa var. glandulosa and P. pallida. The isozymes of malate dehydrogenase, peroxidase, esterase, alcohol dehydrogenase and acid phosphatase from each of these tissues were analysed by starch gel electrophoresis and specific histochemical stains. In the case of each enzyme system examined, there were distinctly different isozymes which could be utilized to differentiate between these two species.  相似文献   

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