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61.
Willian Rogers Ferreira de Camargo Nícholas Ferreira de Camargo Danilo do Carmo Vieira Corrêa Amabílio J. Aires de Camargo Ivone Rezende Diniz 《Journal of insect science (Online)》2015,15(1)
Sexual dimorphism is a pronounced pattern of intraspecific variation in Lepidoptera. However, moths of the family Sphingidae (Lepidoptera: Bombycoidea) are considered exceptions to this rule. We used geometric morphometric techniques to detect shape and size sexual dimorphism in the fore and hindwings of seven hawkmoth species. The shape variables produced were then subjected to a discriminant analysis. The allometric effects were measured with a simple regression between the canonical variables and the centroid size. We also used the normalized residuals to assess the nonallometric component of shape variation with a t-test. The deformations in wing shape between sexes per species were assessed with a regression between the nonreduced shape variables and the residuals. We found sexual dimorphism in both wings in all analyzed species, and that the allometric effects were responsible for much of the wing shape variation between the sexes. However, when we removed the size effects, we observed shape sexual dimorphism. It is very common for females to be larger than males in Lepidoptera, so it is expected that the shape of structures such as wings suffers deformations in order to preserve their function. However, sources of variation other than allometry could be a reflection of different reproductive flight behavior (long flights in search for sexual mates in males, and flight in search for host plants in females). 相似文献
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63.
Larissa Alves Guimar?es Paula Christine Jimenez Thiciana da Silva Sousa Hozana Patrícia S. Freitas Danilo Damasceno Rocha Diego Veras Wilke Jesús Martín Fernando Reyes Otília Deusdênia Loiola Pessoa Letícia Veras Costa-Lotufo 《Marine drugs》2014,12(12):5839-5855
The present study highlights the biological effects of chromomycin A2 toward metastatic melanoma cells in culture. Besides chromomycin A2, chromomycin A3 and demethylchromomycin A2 were also identified from the extract derived from Streptomyces sp., recovered from Paracuru Beach, located in the northeast region of Brazil. The cytotoxic activity of chromomycin A2 was evaluated across a panel of human tumor cell lines, which found IC50 values in the nM-range for exposures of 48 and 72 h. MALME-3M, a metastatic melanoma cell line, showed the highest sensitivity to chromomycin A2 after 48h incubation, and was chosen as a model to investigate this potent cytotoxic effect. Treatment with chromomycin A2 at 30 nM reduced cell proliferation, but had no significant effect upon cell viability. Additionally, chromomycin A2 induced accumulation of cells in G0/G1 phase of the cell cycle, with consequent reduction of S and G2/M and unbalanced expression of cyclins. Chromomycin A2 treated cells depicted several cellular fragments resembling autophagosomes and increased expression of proteins LC3-A and LC3-B. Moreover, exposure to chromomycin A2 also induced the appearance of acidic vacuolar organelles in treated cells. These features combined are suggestive of the induction of autophagy promoted by chromomycin A2, a feature not previously described for chromomycins. 相似文献
64.
Effect of different termite feeding groups on P sorption and P availability in African and South American savannas 总被引:1,自引:0,他引:1
Danilo López-Hernández Michel Brossard Jean-Claude Fardeau Michel Lepage 《Biology and Fertility of Soils》2006,42(3):207-214
Nest structures of six termite species, four with epigeous (above-ground) and two with subterranean nests were analysed to
find out how their building and feeding habits could be related to their nests phosphorus status compared with control soils.
Termite nest structure was found to affect significantly the P status in savanna soils: mounds of the African Trinervitermes geminatus and the South American Nasutitermes ephratae (both grass-feeders) displayed a greater amount of available P, especially in the inner part of the nest, than the surrounding
soil. The abundant quantities of dead grass material stored in the mound can explain the available soil P increase. A similar
increase in P availability was also found for the soil-feeder Cubitermes severus. In mounds of Macrotermes bellicosus, on the other hand, there was a drastic increase in P sorption (and a corresponding decrease in available P) compared to
adjacent soils, which was attributed to the building strategy of this species. M. bellicosus selected clay from subsoil to build its nest structure. The data obtained for the subterranean species Ancistrotermes cavithorax and Microtermes toumodiensis indicated also that there is an increase in P sorption in mounds when compared with associated topsoils. Consequently, the
nest structures of only certain termite species should be considered, and utilised, as a soil amendment in place of fertilisers.
This impact on the P cycle in savannas seems to be related to the termite feeding status and to the type of material utilised
in nest building. This should be taken into account before using termite nest material in soil fertility status improvement. 相似文献
65.
Michel Brossard Danilo López-Hernández Michel Lepage Jean-Claude Leprun 《Biology and Fertility of Soils》2007,43(4):437-447
Nest structures of two termite species (Trinervitermes spp.) with epigeal (above-ground) mounds were analyzed to compare their nutrient status with that of adjacent soils. To take
into account soil variability, the observations and samplings were made in three toposequences of different and representative
West African savanna soils. The data showed the high degree of adaptation of these termite species to a large range of soil
types and environments. Mounds of Trinervitermes geminatus and Trinervitermes trinervius, both grass-feeders, contained more clay, organic matter (OM), and exchangeable cations than the surrounding surface layer
soil. The storage of OM and exchangeable cations was determined for T. geminatus nests and compared to the surrounding soil. Despite substantial nutrient storage in mounds, its total weight appeared low
when compared to the nutrient storage in the surrounding 0–15 cm of soil surface layer. This illustrates how contradictory
points of view on the use of termite mounds in agriculture need to be clarified using a classical approach that takes into
account data by species; and this also evaluates the contribution of different termite mounds to nutrient fluxes and storage
and the exact stocking rate of living mounds. 相似文献
66.
67.
Sergio Miguel Vélez-Zambrano Jefferson Bertin Vélez-Olmedo Susana García Bianca S. A. Bonfim Pedro Emilio Cedeño Danilo Pinho 《Forest Pathology》2023,53(5):e12830
Teak is a very important tropical timber in Ecuador. In 2017, teak samples displaying stem canker symptoms were collected in two provinces of Ecuador. From 11 symptomatic trees, 11 isolates resembling a species of Lasiodiplodia were obtained. All isolates obtained induced stem canker on teak plants after artificial inoculation, confirming them as the cause of the observed canker symptoms. Bayesian inference with concatenated sequences of complete ITS and partial TEF-α and β-TUB gene sequences from two representative isolates clustered teak isolates with other sequences of Lasiodiplodia theobromae available in Genbank. This is the first report of L. theobromae causing stem canker on teak plants in Ecuador. 相似文献
68.
Luis Augusto Di Loreto Di Raimo Eduardo Guimarães Couto José Alexandre Mello Demattê Ricardo Santos Silva Amorim Gilmar Nunes Torres Cassiano Cremon Danilo César de Mello Edwaldo Dias Bocuti Raul Roberto Poppiel Adeilson Nascimento da Silva Lucas Nunes Lima Luis Carlos Gomes Neto 《European Journal of Soil Science》2022,73(2):e13227
69.
Ireneo J. Manguiat Danilo M. Mendoza Arnel M. Perez Tadakatsu Yoneyama 《Soil Science and Plant Nutrition》2013,59(4):593-604
Abstract A study was carried out to compare the difference or N-yield method with the 15N natural abundance method for the estimation of the fractional contribution of biological N2 fixation in the different plant parts of nodulating and non-nodulating isolines of soybeans. The results indicated that the δ15N values of most plant parts of soybeans were significantly lower (p<0.05) in the nodulating than in the non-nodulating isoline. However, in the case of the root+nodule component, the δ15N value was higher in the nodulating than in the non-nodulating isoline possibly due to isotopic discrimination of 15N over 14N which may have occurred in the nodules. Inoculation of soybeans with the Bradyrhizobium japonicum strain CB 1809 increased significantly (p<0.05) the δ15N value of the root+nodule component implying that the effectiveness of the soybean-rhizobium symbiosis had increased by inoculation. Percentage of plant N derived from atmospheric N2 fixation (%Ndfa) estimated by the 15N natural abundance method was highly correlated (r=0.762, p<0.01) with that by the difference or N-yield method and the differences between the two methods were not statistically significant. The agreement between the two methods was closer at maturity than at the early reproductive stage. The %Ndfa obtained by the difference method ranged from 48.4 to 92.6% whereas the %Ndfa obtained by the 15N natural abundance method ranged from 43.2 to 92.4% in the different plant parts. Based on the 15N natural abundance method, approximately 15% of the N in pod, shoot, grain, and shell was derived from the soil but in the case of stover, this fraction was about 55%. 相似文献
70.