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1.
Summary In a survey, out of the nineteen genera of non-leguminous angiosperms that are already reported to bear actinomycete-induced nitrogen-fixing root nodules from various parts of the world, the species of seven genera (Alnus, Elaeagnus, Hippophaë, Coriaria, Datisca, Rubus and Casuarina) have been located in Pakistan and checked for nodulation. All the investigated species of the these genera, except those of Rubus and some of the introduced species of Casuarina, were found to bear nodules. In all 12 species belonging to six genera of five families have been recorded to bear actinorhizal nodules in Pakistan.  相似文献   

2.
地衣是低等植物的重要类群,为菌藻共生体,全世界已知有500多属26 000余种,中国有232属1 766种.我国历代本草记载药用地衣约200种,著名的有石蕊、松萝等,秦岭太白山有药用地衣37种,其中常用13种.其主要成分为地衣多糖和地衣酸,具有抗肿瘤、抗辐射及抗菌等生物活性,太白山药用地衣是陕西民间中草药的重要组成部分,具有一定的开发应用潜力.  相似文献   

3.
西沙群岛海域造礁石珊瑚物种多样性与分布特点   总被引:5,自引:0,他引:5  
2006年3-5月,采用国际通用的截线样带法对海南省西沙群岛主要珊瑚礁海域的18个岛礁造礁石珊瑚进行了实地调查,共记录13科45属188种,其中62个新记录种.整合文献资料,该海域共记录造礁石珊瑚13科50属204种,基本包括分布在我国(不含台湾省)的所有造礁石珊瑚科属和绝大多数种类.造礁石珊瑚以生长速度快的分枝状珊瑚为主.物种多样性最高的是华光礁海域、金银岛海域和永兴岛海域.聚类分析可以把18个调查岛礁分成3个类群:有人类居住的大型环礁群、独立岛礁群和无人居住的大型环礁群(华光礁).为了有效保护珍稀的造礁石珊瑚资源,按照其种类多样性和分布特点重点保护关键海域是十分必要的.  相似文献   

4.
This paper provides a checklist and summary of what is currently known of the variation in infant contact, sleeping site preference and aspects of social cohesion in the nocturnal primates of Africa. Genera and species are compared, based on previously unpublished field observations and a review of the literature. There is a clear pattern of similarity between the species within each genus and distinct differences between genera. Species in the same genus tend to be ecologically equivalent and replace each other allopatrically, whereas species in different genera are more likely to be sympatric, with up to 6 species living together. Maximum sympatry within genera is found in Otolemur and Galagoides, where species are ecologically divergent. This may reflect an ancient origin of species within these genera or suggest that further taxonomic revision is required at the generic level. Some data are recorded for the first time for species that have only recently been separated (cryptic species), but some taxa remain very poorly known. It is concluded that field studies are still at an elementary stage and further research with radio tracking is urgently needed in the face of rapidly declining habitats.  相似文献   

5.
在最近提交的天目山姬小蜂科的报告基础上,本文再次对浙江该科昆虫进行了分类学研究。根据从天目山采集的标本和中国科学院动物研究所动物标本馆馆藏标本。研究了分属于姬小蜂科4个亚科的20属35种。文中提供了亚科,属及物种的检索表,同时还提供了关键性状的扫描电镜照片,每个物种均附有最新的寄主记录和分布记录。根据现有材料,对浙江姬小蜂科昆虫进行了初步的分析。  相似文献   

6.
Abstract The genus Cathaya discovered in Kwangsi, Sichuan, Hunan and Guizhou is endemic in China. Only one species (C. argyrophylla Chun et Kuang) has so far been known in the genus. The question on it’s systematic position in the family Pinaceae has been much debated. However, according to some taxonomists and morphologists, this genus is related to genera Pinus, Picea and Pseudotsuga of the Pinaceae. No phytochemical data, especially of serratene components on Cathaya have been recorded. This paper deals with the systematic position of Cathaya in Pinaceae based on seven known components of serratene family which are isolated from the trunk of Cathaya argyrophyua growing in Sichuan. A comparative study on serratene components of Cathaya with other genera ofPinaceae showed that Cathaya is related to genera Pinus and Picea.  相似文献   

7.
An annotated list of chironomid species from some waterbodies and watercourses of Mongolia identified by an imaginal developmental stage is presented. The list includes 97 species of 39 genera and 5 subfamilies: Tanypodinae (6 species), Diamesinae (1), Prodiamesinae (2), Orthocladiinae (33), and Chironominae (55). Of all found chironomid imagos, 11 species have been earlier identified for the Mongolian fauna, the other 86 species have been registered for the first time. The largest number of species has been recorded in Lake Sangiyn-Dalai—28; in Lake Ugiy and River Ider—19 species. In the rest of the lakes, the number of recorded species varies from 18 to 10 species, and in rivers, from 13 to 2. Most of the species are boreal and widespread. The number of Paleoarctic species amounts to 44 and Holarctic species amounts to 49.  相似文献   

8.
Isolations of the rhizobia from nodules of field plants of Ulexeuropaeus and Medicago lupulina have been examined for effectivenessin fixation of nitrogen by inoculating them into host plantsgrowing in a medium free of combined nitrogen. The results indicatethat vigorous fixation may be presumed to occur in associationwith field plants of the Ulex species, but that fixation inMedicago is probably decreased by the presence of ineffectiverhizobia in some nodules. The general importance of fixationin wild legumes is discussed, and it is pointed out that dueattention must be paid to non-legume genera with root nodules.These genera are locally abundant, and in former periods werestill more prominent in some regions of the world.  相似文献   

9.
A checklist of the species of springtails (Hexapoda: Collembola) hitherto recorded from Turkey is presented. This list contains 53 species belonging to 39 genera in 13 families. The diversity of Collembola in Turkey is poorly known and it is clear that numerous species wait to be discovered.  相似文献   

10.
S. Uemura 《Plant and Soil》1971,35(1):349-360
Summary Among plants native to Japan, nodule formation is confirmed in 14 species and varieties of Alnus, 10 of Elacagnus, 2 of Myrica and 1 of Coriaria, in a number of instances for the first time. Plants of 20 foreign species, in 8 genera, which bear nodules in their native countries, were raised in the nursery in Tokyo; only species of Alnus, Myrica and Ceanothus formed nodules. No nodules were found on native plants ofDryas octopetala var.asiatica. In a trial extending over 12 years evidence was obtained that the growth ofPinus thunbergii was benefited by underplanting withMyrica rubra, a result attributed to nitrogen fixation in the root nodules of the latter species. In the attempted isolation of the endophytes from the nodules of Alnus and other non-legume Angiosperms, although actinomycetes peculiar to the host species were usually obtained from the nodules, none of the isolates induced nodules in re-inoculation tests. Also from Podocarpus nodules actinomycetal and bacterial strains were commonly isolated; re-inoculation tests with these are in progress.  相似文献   

11.
The Australian cestode fauna remains poorly documented with a total of 342 species recorded to date. The best-studied host groups are the elasmobranchs and the marsupials, but even in these groups, only 32 and 25% of known host species, respectively, have been examined for parasites. Overall, cestodes have been reported from only 5% of the known vertebrate species. Representatives of virtually all cestode orders and most of the cyclophyllidean families have been recorded from Australia. In spite of these deficiencies, some biogeographical patterns are discernible. In the elasmobranchs, a significant proportion of the known cestodes is endemic while other associations exist with eastern Pacific and Indo-west Pacific faunas. Also identifiable is a group of cosmopolitan species. The nematotaeniids of amphibians suggest Gondwanan affiliations, while the known proteocephalideans, parasitic in reptiles and amphibians, may represent an Asian invasion. Associations of the avian cestodes represent an unexplored but potentially rewarding avenue of biogeographical study. The cestodes of mammals include families with a Gondwanan distribution (Linstowiidae, Hymenolepididae) as well as those (Anoplocephalidae) with an apparent origin in southeast Asia. In addition, a number of genera of cyclophyllidean cestodes (Anoplotaenia, Dasyurotaenia) occurring in marsupials represent biogeographical challenges, not being accommodated within any of the known cestode families. The Australian cestode fauna therefore provides potentially outstanding opportunities for studies of the biogeographical relationships of a number of cestode groups.  相似文献   

12.
13.
An account of the pollen morphology found in the genera Dysoxylum and Pseudocarapa (Meliaceae) is presented. Pollen grains are illustrated by means of electron and some light micrographs. The majority of taxa release grains as tetra-colporate monads. Tetrads have previously only been known in Pseudocarapa. They are also recorded here in three species of Dysoxylum. The taxonomic implications of this are discussed and Pseudocarapa is reduced to a synonym of Dysoxylum.  相似文献   

14.
Adult butterflies are known to visit a wide variety of food substrates, but, with the exception of flower visitation, little is known about what substances are being sought or what determines substrate choice. This is especially true for the Riodinidae, a large family [c. 1300 spp.) of almost exclusively Neotropical butterflies. We present adult male feeding records for 124 species in 41 genera of Riodinidae (out of a total of 441 species in 85 genera collected in the study), based on ten months sampling in Ecuador. Records of food substrates visited in this study include flowers, damp sand or mud (‘puddling’) and rotting carrion. Rotting carrion placed in traps was the most frequently recorded food source in terms of numbers of individuals and taxa, attracting 89 species from 32 genera. A correlation is found between food substrate choice and morphology, specifically wing area to thoracic volume ratio (WA: TV ratio). Our data suggest the possible existence of two adaptive syndromes whose species have significantly different mean WA:TV ratios and differing suites of accompanying ecological traits, with lower ratios being significantiy correlated with species that were recorded feeding. Among species recorded feeding, carrion feeders and puddlers have significantly lower mean WA:TV ratios than flower nectarers, and carrion feeders have a lower mean WA:TV ratio than species not recorded on this food source, a correlation that is significant across all tribes and within some tribes (Riodinini and Saratoni). We reanalyse previously published data on flight and morphology for species in other butterfly and moth families and show mat the ratio of wing area to thoracic mass is significantly negatively correlated with flight speed and oxygen consumption (a direct indicator of metabolic rate). We suggest that adult male riodinids may puddle and feed at rotting carrion to supplement nutrient stores from larval feeding, not only to increase reproductive success, but also to provide the necessary nutrients to maintain high metabolic rates during rapid flight.  相似文献   

15.
Summary Of the various groups of non-leguminous seed plants that have been implicated by workers in other regions in symbiotic nitrogen fixation, though on evidence varying in quality, the indigenous flora of southern Africa includes 1 species of Stangeria, 26 of Encephalartos, 4 of Podocarpus, 9 of Myrica, 1 of Psychotria, 41 of Pavetta, 19 of Dioscorea and 1 of Gunnera. It is probable that all the indigenous cycads bear the coralloid, alga-infested roots found on cycads of other regions; evidence that nitrogen fixation occurs in these structures is presented for two of the species. The indigenous podocarps bear the numerous, nodular structures on their roots found in other species, and tests with one species indicated that a very small fixation of nitrogen might be associated with the nodules. All the 9 species of Myrica were found to bear root nodules which are shown to fix nitrogen vigorously. All the indigenous species of Pavetta that were examined bear leaf nodules; tests on two species indicated that nitrogen fixation is associated with the nodulated leaves, but only to a slight extent, so that the plants are unable to make appreciable growth in a nitrogen-free rooting medium. In testing for the occurrence of nitrogen fixation the N15, acetylene-reduction and long-term growth methods were used.  相似文献   

16.
Thirty-six species of coccidia, all members of the genus Eimeria, have been described from 3 of the 9 genera and 11 of the more than 48 species in the lagomorph family Leporidae. All these are described briefly in the present paper and their synonymies are given. Coccidia have been described from the single species of Oryctolagus, from 4 of the 13 species of Sylvilagus and from 6 of the 26 species of Lepus. These genera have 12, 12, and 14 known species of Eimeria, of which only 2 are shared by Oryctolagus and Sylvilagus. Lepus has none of the coccidia of these genera. One species is known to occur in the bile ducts of the liver, 13 in the intestine, and the location of 22 is unknown. Life cycles have been determined for 9 of the species, of which 8 have been worked out in the domestic rabbit Oryctolagus and 1 in the cottontail Sylvilagus.  相似文献   

17.
The total diversity of the monogenean genus Gyrodactylus is evaluated. There are 409 potentially valid species names within the genus, recorded from c. 400 host species. Five species have been placed within Fundulotrema and an additional 51 Gyrodactylus species names represent synonyms, nomina nuda or have been reassigned to other non-viviparous monogenean genera. While the majority of Gyrodactylus species (59%) are recorded from single hosts, some have a much broader broad range.  相似文献   

18.
福利祝蛾属Frisilia在中国已记载2种,本文记述2新种,安宁福利祝蛾F.anningensissp.nov.和条斑福利祝蛾F.siriapunctatasp.nov.及一新纪录种,黄福利祝蛾F.homochloraMeyrick,至此我国的福利祝蛾达5种。文中对属征作了综述,并编制了分种检索表。模式标本保存在中国科学院动物研究所。  相似文献   

19.
Phrygionis and Pityeja belong to the Palyadini, a tribe of neotropical Ennominae. The moths of both genera bear striking wing markings and mere variants were frequently described as species with the consequence that species diversity was overestimated. Numerous taxonomic changes are made in this work based on the study of primary types and much other material. Variation and distribution is recorded for each species and subspecies. Phylogenetic relationships within Phrygionis are examined, and comments are made on the evolution of wing pattern within this genus.
Fifteen full species are recognized in this study (13 in Phrygionis and two in Pityeja ), of which four (all in Phrygionis ) are described as new; 19 species-group (specific and subspecific) names refer to valid taxa. Twenty-four species-group names are synonymized (19 in Phrygionis and five in Pityeja ) and five are recombined with different genera (four with Phrygionis and one with Pityeja ). Three generic names are synonymized (one in Phrygionis and two in Pityeja ).  相似文献   

20.
G. Bond 《Plant and Soil》1971,35(1):317-324
Summary The world-wide survey under the IBP of root-nodule formation in non-leguminous Angiosperms is progressing reasonably satisfactorily, and it is anticipated that when all the results have been collated a useful body of new data will be yielded. In recent studies, also forming part of the IBP, in the author's laboratory, the nodules of further species in the genera Alnus, Myrica, Ceanothus, Coriaria and Dryas have been examined for nitrogen-fixing properties, with positive results. Also the extent to which the nodule endophytes from species of Alnus and Myrica respectively are able to symbiose satisfactorily with other host species in the same genus has been investigated, and the conclusion reached that especially in Myrica there is very considerable specialisation among the endophytes. A marked diurnal variation in the rate of fixation of nitrogen in the nodules of non-legumes growing in a glasshouse lit by daylight has been found, with maximal rates being attained around midday. The implication is that this is the period of the maximal availability of carbohydrates in the nodules, but actual analyses have so far failed to reveal this. Analyses of the amino acid composition of the nodules in several genera have shown that except in Alnus, where citrulline is prominent, asparagine is in most cases the dominant amino acid.  相似文献   

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