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201.
ESTELA NOVAK EDNA FREYMULLER HAAPALAINEN SOLANGE DA SILVA JOSE FRANCO DA SILVEIRA 《The Journal of eukaryotic microbiology》1988,35(3):375-378
Here we describe a method that allows the isolation of intact trypanosomatid symbionts in amounts sufficient for biochemical analysis. The isolated symbionts retain their characteristic morphological features and are reasonably free of subcellular debris. They actively incorporate [3H]leucine and [35S]methionine into proteins. Chloramphenicol and rifampicin at 50 μg/ml almost completely inhibit the incorporation of protein precursors. The inhibition of protein synthesis by the antibiotics provides direct evidence for the existence of a prokaryotic protein-synthesizing system in this unusual intracellular structure. The pattern of protein synthesis of the isolated symbionts is complex. Several symbiont polypeptides are absent or poorly represented in the flagellate. 相似文献
202.
203.
A. F. BAFFA D. C. P. CAMARA J. R. SANTOS‐MALLET E. R. DA SILVA J. COSTA S. P. C. FREITAS 《Medical and veterinary entomology》2017,31(2):192-199
Morphological and structural features of the sperm of the Triatoma brasiliensis Neiva, 1911 (Hemiptera: Reduviidae) species complex were examined in this first study investigating the sperm of Heteroptera and the genus Triatoma. Males were dissected and their seminal vesicles removed. For measurement, seminal vesicles were squashed on glass slides, spread, fixed and observed under a photomicroscope. The images were analysed and measures of sperm were made. Data were analysed using one‐way analysis of variance and Tukey's test to detect differentiation among taxa. Furthermore, seminal vesicles were prepared for studies of transmission electron microscopy. All taxa studied showed polymorphic (short and long) sperm. The sperm of Triatoma brasiliensis macromelasoma was significantly longer (in total length) than that of the other four members of the complex, which supports the hypothesis of hybrid speciation of this member of the complex as an increase in the size of typical hybrids under heterosis was previously shown. The sperm cells of the five taxa have similar ultrastructural morphology. The ultrastructural features observed confirm the hypothesis, raised by previous studies, that they are synapomorphic to the suborder Heteroptera. 相似文献
204.
N. A. SOUZA C. A. ANDRADE-COELHO V. C. SILVA R. D. WARD A. A. PEIXOTO 《Medical and veterinary entomology》2009,23(3):287-292
The developmental cycles of five Brazilian populations of the Lutzomyia longipalpis Lutz & Neiva species complex (Diptera: Psychodidae) were compared under laboratory conditions. Three of the populations were derived from insects collected in allopatric sites at Natal (Rio Grande do Norte State), Jacobina (Bahia State) and Lapinha Cave (Minas Gerais State). The other two originated from Sobral (Ceará State), where the males of two sympatric species can be distinguished by the presence of one (1S) or two (2S) pairs of abdominal spots. The results of the present study clearly show that all three populations whose males produce C16 pheromones and use pulse-type copulation songs (Jacobina, Lapinha Cave and Sobral 1S) are more easily adapted to the colonization conditions used in our laboratory, producing larger egg batches, with higher survival and an overall faster developmental cycle. This contrasts with populations producing C20 male pheromones and using burst-type copulation songs (Natal and Sobral 2S) that produce smaller egg batches, have higher oviposition mortality and a slower rate of development under identical laboratory conditions. In conclusion, these phenological differences are a further indication of the differentiation of the siblings within the Lu. longipalpis species complex. 相似文献
205.
ADRIAN A. BARNETT SARAH A. BOYLE MARILYN M. NORCONK SUZANNE PALMINTERI RICARDO R. SANTOS LIZA M. VEIGA THIAGO H.G. ALVIM MARK BOWLER JANICE CHISM ANTHONY DI FIORE EDUARDO FERNANDEZ‐DUQUE ANA C. P. GUIMARÃES AMY HARRISON‐LEVINE TORBJØRN HAUGAASEN SHAWN LEHMAN KATHERINE C. MACKINNON FABIANO R. DE MELO LEANDRO S. MOREIRA VIVIANE S. MOURA CARSON R. PHILLIPS LILIAM P. PINTO MARCIO PORT‐CARVALHO ELEONORE Z. F. SETZ CHRISTOPHER SHAFFER LÍVIA RODRIGUES DA SILVA SULEIMA DO S. B. DA SILVA RAFAELA F. SOARES CYNTHIA L. THOMPSON TATIANA M. VIEIRA ARIOENE VREEDZAAM SUZANNE E. WALKER‐PACHECO WILSON R. SPIRONELLO ANN MACLARNON STEPHEN F. FERRARI 《American journal of primatology》2012,74(12):1106-1127
Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a “local pattern” of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types. Am. J. Primatol. 74:1106‐1127, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
206.
Complete removal of foliage-bearing branches from tea plantsrecovering from pruning at low altitudes has been observed toresult in a scorching of the newly-developing buds and shoots.Studies on the xylem sap composition have revealed that thereis a very sharp increase in the amino-N content of the sap.The relationship between the sap composition and the physiologyof the plant is discussed. 相似文献
207.
E. C. GONALVES A. SILVA M. S. R. BARBOSA M. P. C. SCHNEIDER 《Molecular ecology resources》2004,4(3):406-408
Ten highly polymorphic microsatellite loci are described for Amazonian red‐handed howlers (Alouatta belzebul), an endemic Brazilian primate species subject to intense hunting pressure. The number of alleles observed in 30 individuals ranged from nine to 20, and observed heterozygosity varied from 0.35 to 0.93. No linkage associations were evident from pairwise comparisons of loci. These microsatellites offer a powerful tool for fine‐scale studies of genetic structure in both captive colonies and wild populations of red‐handed howlers. 相似文献
208.
The ecology of nitrogen fixing blue-green algae in rice fieldsof Central Sri Lanka was studied using multi-variate techniquesof analyses. In this study 73 strains of heterocystous bluegreenalgae, belonging to 21 genera were isolated and the distributionof the 46 most abundant strains was examined in relation toecological parameters. Besides pedological factors such as pH, water holding capacityand available phosphorus; environmental factors including rainfalland altitude have shown up as parameters influencing the distributionof the algal species. On the other hand, soil organic carbon,total nitrogen, potassium and calcium, do not appear to playan important role in determining the composition of the algalflora. While certain algal species were ubiquitous in their distributionsome were restricted, and a few even showed a tolerance to standswith low soil pH and low levels of phosphorus. The agronomicpotential of such species is of value especially in relationto rice-growing soils of this District, where low pH and lowlevels of phosphorus are major limiting factors for the profusegrowth of bluegreen algae. Blue-green algae, nitrogen fixation, Sri Lanka, rice-growing soils, multivariate analysis 相似文献
209.
1. The selection of an oviposition site by a phytophagous insect can depend on many factors, including the risk of predation. Many species avoid predators by laying eggs where enemies searching host plants are unlikely to find them. 2. Females of the Peruvian butterfly, Oleria onega Hewitson (Lepidoptera: Nymphalidae: Danainae: Ithomiini) lay most of their eggs (76 ± 9%) off the host plant, Solanum mite Ruiz & Pav. These off‐host eggs may be laid up to 0.5 m from the nearest host‐plant individual, on twigs or leaf litter, as well as on living plants of species unsuitable for larval food. 3. Disappearance of eggs on and off the host plant was recorded by transferring eggs laid in captivity to known locations in the wild and recording rates of disappearance before the larvae emerged. After 2 days, eggs on the host were significantly more likely to have disappeared compared to eggs laid elsewhere. 4. We conclude that a high risk of predation is a likely trigger that caused O. onega to evolve a behaviour of laying eggs off its host plant. 相似文献