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5 new taxa are described and illustrated; their position within the subgenus is discussed:T. hirta W. Till & L. Hromadnik,T. cotagaitensis L. Hromadnik,T. caliginosa W. Till, andT. gilliesii Baker subsp.polysticha W. Till & L. Hromadnik are members of a group includingT. myosura Grisebach exBaker,T. mandonii E. Morren exMez in DC.,T. retorta Grisebach exBaker em.Grisebach andT. andicola Gillies exBaker. T. brealitoensis L. Hromadnik is related toT. angulosa Mez in DC. but distinct and possibly of hybrid origin.
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Zusammenfassung In dem großen Hochwaldgebiet, das sich am Fuße der Anden von Jujui bis Orán erstreckt, erbeutete der Verf. am 3. Januar 1969 ein junges Weibchen vonButeo albigula, erster Nach-weis dieser Art aus Argentinien. In dem gleichen Waldkomplex und in annähernd gleicher Höhenlage ist auchButeo brachyurus gesammelt worden. Daraus wird gefolgert, daß diese beiden Bussarde nicht subspezifisch verschieden sind (wieRand urteilte), sondern als zwei Spezies zu gelten haben.
Sinopsis Una hoven hembra deButeo albigula Philippi fué cazada en Orán del 3 de Energo 1969 por el autor. La especie es nueva para la fauna Argentina. Como la posición sistematica de esta forma era dudosa, el hallazgo es interesante, porque en la misma región ya es conocidaButeo brachyurus Vieillot. La región de las selvas del Noroeste, al pie de los Andes, incluye áreas grandes de bosque humedos, con alturas variables, desde la frontera con Bolivia hasta el sudeste de la provincia de Jujuy. Como ahora las dos formas,albigula y brachyurus son habitantes de la misma región, parecería que son especies y no subespecies.
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Investigations of the ground water of the French Mediterranean coast gave 28 different species of harpacticoid copepods. Among them, six species are new to the French coast and three species and one form are described as new, viz. Ectinosoma mediterraneum sp.n., Sigmatidium rouchi sp.n., Ameira atlántica mediterránea forma n., and Taurocletodes gallicus sp.n. Comparison of the harpacticoid fauna of the French coast with other marine districts shows close relations to the fauna of the Black Sea, while the relations to the Atlantic coast (Portugal) and the Baltic Sea (Bay of Kiel) are only remote. A genus is established, Taurocletodes gen.n. Sigmatidium noodti sp.n. is described from the Sea of Marmara.  相似文献   

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Flowers of Voandzeia subterranea are positively geotropic andthis helps their entry into the ground. The ovary develops onlywhen it is on the surface of, or inside, the soil. The transformationinto fruit occurs in two stages: (a) definite development of pod, followed by (b) development of seed. The first stage occurs during the first 30 days after fertilizationand the second stage lasts for about 10 days. Maturity is characterizedby dryness and browning of the interior of the shell and appearanceof brown patches on it. The part of the pod on which the pedicelsubsists is the upper part and the lower part is the portionwhere the style is attached.  相似文献   

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Potato mop-top virus (PMTV) was detected by ELISA in primary zoospores from four out of six isolates of Spongospora subterranea f.sp. subterranea. One virus-free isolate (N) of S. subterranea was used to acquire PMTV from potato roots and to transmit the virus to healthy plants. A mono-fungal culture of S. subterranea (isolate N) was derived by infecting tomato plant roots with a single cystosorus. The culture was used successfully to acquire PMTV from the roots of infected Nicotiana debneyi plants that had been manually inoculated with virus isolates, and subsequently to transmit the virus to healthy bait plants. These experiments confirm that S. subterranea is a vector of PMTV. Two PMTV isolates that had been maintained by manual inoculation for 19 and 21 passages were also acquired and transmitted by the fungus culture.  相似文献   

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B. -P. Elendt 《Protoplasma》1990,154(1):25-33
Summary The effect of selenium deprivation onDaphnia magna was examined under controlled rearing conditions in a synthetic culture medium. After three generations, fertility was significantly reduced in deprived (Se) animals. Growth and mortality of parent daphnids and development of parthenogenetic eggs were not affected during this period. In the fourth generation Se daphnids rejected parts of their second antennae. At the ultrastructural level antennal muscle tissue was severely affected. Animals deprived of selenium had mitochondria and sarcoplasmic reticulum with myelin-like alterations. Giant lysosomes were present and complete lysis of muscle fibrils was observed in antennal muscle cells. These alterations are characteristic features of peroxidic damage in tissues. This interpretation is consistent with the function of selenium as a constituent of the enzyme glutathione peroxidase which protects cells from peroxidation. Selenium should be included in synthetic culture media for daphnids.Abbreviations GSH-Px selenium dependent glutathione peroxidase - Se+/Se selenium supplemented (control)/selenium deprived animals - SOD Superoxide dismutase - SR sarcoplasmic reticulum  相似文献   

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The effects of density and environmental complexity on distance of separation when agonistic acts were executed were studied in the spider crab Microphrys bicornutus. Crabs were held at one of two densities and either in a simple (no structural complexity) or complex environment (rocks added to the aquarium). Behavior patterns and the distances at which they were executed were observed in a neutral container. Analysis of the 580 behavior-distance measurements indicated effects of both density and environmental complexity.  相似文献   

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Summary To improve biological nitrogen fixation in bambara groundut (Voandzeia subterranea (L.) Thouars), the relative effectiveness of 24 cultivars was studied in the field at two experimental stations selected for their different ecological conditions. Thirty oneRhizobium strains were isolated and 12 cultivars were screened during this study. Both indigenous and introduced NiftalRhizobium strains were used during a second study on host cultivars xRhizobium strains interactions. Nodulation index and shoot dry weight were used to assess the efficiency. The widest effectiveness spectrum was observed with the indigenous strain MAO 113 and the introduced strain TAL 22.
Resumen Afín de mejorar la fijación biológica de nitrógeno en el cacahuete de Bambara (Voandzeia subterranea (L.) Thouars), se realizó un estudio de su efectividad relativa en campo en dos estaciones experimentales seleccionadas por sus distintas condiciones ecológicas. Durante este estudio se aislaron treintaiuna cepas deRhizobium y se probaron doce cultivares del huésped. En un segundo ensayo se estudiaron las interacciones huésped xcepa deRhizobium para lo cual se utilizaron cepas deRhizobium Niftal tanto indígenas como introducidas. La eficiencia se valoró determinado el índice de nodulación y el peso seco de la parte aerea. El espectro más amplio de eficacia se observó con la cepa indígena MAO 113 y la introducida TAL 22.

Résumé Dans le but d'améliorer la fixation biologique d'azote dans la noix de Bambara (Voandzeia subterranea (L.) Thouars), l'efficacité relative de 24 cultivars a été étudiée sur le terrain dans deux stations expérimentales choisies pour leurs conditions écologiques différentes. Trente-etune souches deRhizobium ont été isolées et 12 cultivars ont été testés au cours de cette étude. Tant les souches indigènes deRhizobium que celles Niftal introduites ont été utilisées au cours d'une deuxième étude sur les interractions entre les souches deRhizobium et les cultivarshôtes. L'indice de nodulation et le poids sec de la pousse ont été utilisés pour l'établissement de l'efficience. Le spectre d'efficience le plus large a été observé avec la souche indigène MAO 113 et la souche introduite TAL 22.
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Spongospora subterranea, which causes powdery scab of potato, infects a diverse range of plant species. Crop rotation as a powdery scab management tool will be compromised if pathogen hosts exist between potato crops. Opium poppy (Papaver somniferum) and pyrethrum (Tanacetum cinerariifolium) are important crops within intensive vegetable production rotations in NW Tasmania. Measurements of S. subterranea soil inoculum within a commercial field showed pathogen amounts were substantially elevated following an opium poppy crop, which suggested host status. In glasshouse testing, opium poppy and pyrethrum were confirmed as hosts of S. subterranea, with opium poppy the more susceptible of the two. Both species were less susceptible than tomato, a known host. Observations of early growth suggested inoculation impacts on all three plant species, although at 16 (tomato and opium poppy) or 26 (pyrethrum) weeks postinoculation, only tomato had significantly reduced shoot and root development. The role of rotation crops in inoculum persistence and the possible role of S. subterranea as a minor pathogen of nonpotato crops are discussed.  相似文献   

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Multilocus sequence analysis based on hypervariable housekeeping proteins was utilized to differentiate closely related species in the family Enterobacteriaceae. Of 150 housekeeping proteins, the top 10 hypervariable proteins were selected and concatenated to obtain distance data. Distances between concatenated proteins within the family were 0.9–41.2%, whereas the 16S rRNA and atpD‐gyrB‐infB‐rpoB concatenated sequence (4MLSA) distances were 0.8–6.0% and 0.9–22.1%, respectively. These data indicate that phylogenetic analysis by concatenation of hypervariable proteins is a powerful tool for discriminating species in the family Enterobacteriaceae. To confirm the discriminatory power of the 10 chosen concatenated hypervariable proteins (C10HKP), phylogenetic trees based on C10HKP, 4MLSA, and the 16S rRNA gene were constructed. Comparison of average bootstrap values among C10HKP, 4MLSA and 16S rRNA genes indicated that the C10HKP tree was the most reliable. Location via the C10HKP tree was consistent with existing assignments for almost all species in the family Enterobacteriaceae. However, the C10HKP tree suggested that several species (including Enterobacter massiliensis, Escherichia vulneris, Escherichia hermannii, and Salmonella subterranea) should be reassigned to different clusters than those defined in previous analyses. Furthermore, E. hermannii and S. subterranea appeared to fall onto a branch independent from those occupied by the other Enterobacteriaceae. Therefore, we propose Atlantibacter gen. nov., such that E. hermannii and S. subterranea would be transferred to genus Atlantibacter as Atlantibacter hermannii, comb. nov. and Atlantibacter subterranea. comb. nov., respectively.  相似文献   

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Some Crustacea Copepoda from Venezuela   总被引:5,自引:5,他引:0  
The study of 38 samples of aquatic fauna from Venezuela increased the number of known species here from 28 to 66. Fifteen new species for science are described. A list of Copepoda known from the other regions of South America is presented. From this list, it can be said that only 50% of the inland water Copepoda living actually in Venezuela are known.  相似文献   

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Summary The sinus glands of the Brachyura are composed of swollen nerve fiber endings, which store and release secretory material synthesized within cells of the eyestalks, the brain and probably the thoracic ganglionic mass. Removal of the sinus glands from the land crab, Gecarcinus lateralis, does not induce molt, because sinus glands are reservoirs, not sources, of molt-inhibiting hormone. Increase in respiratory rate and fall in respiratory quotient, which follow eyestalk removal and signify the approach of molt, do not occur after sinus gland removal.From recent studies on the eyestalks and brain of the crayfish, Cambarus virilis, it is clear that morphologically the neurosecretory system of this crayfish is similar to that of the land crab. There is a marked resemblance in arrangement of neurosecretory cells and in pathways followed by the fibers, the endings of which form the sinus glands. Maps of eyestalks and brain of Cambarus and Gecarcinus emphasize this fundamental likeness between an astacuran and a brachyuran. Regions in which neurosecretory cells are found have been numbered so that these maps may guide cytological and physiological study on these species and on other decapod Crustacea.This paper was delivered at the Symposium on Neurosecretion held May 11–16, 1953, at the Stazione Zoologica, Naples, Italy. An abstract of this paper. together with summaries of other papers presented at the Symposium, is appearing in the Pubblicazioni della Stazione Zoologica di Napoli.The preparation of this paper was aided by a National Science Foundation (USA.) grant to the first author and by the use of the American Table at the Naples Zoological Station.  相似文献   

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