Brazilian Journal of Biology

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13321

Navegar

Resultados da Pesquisa

Agora exibindo 1 - 5 de 5
  • Imagem de Miniatura
    Item
    Microbiological and faunal soil attributes of coffee cultivation under different management systems in Brazil
    (Instituto Internacional de Ecologia, 2015) Lammel, D. R.; Azevedo, L. C. B.; Paula, A. M.; Armas, R. D.; Baretta, D.; Cardoso, E. J. B. N.
    Brazil is the biggest coffee producer in the world and different plantation management systems have been applied to improve sustainability and soil quality. Little is known about the environmental effects of these different management systems, therefore, the goal of this study was to use soil biological parameters as indicators of changes. Soils from plantations in Southeastern Brazil with conventional (CC), organic (OC) and integrated management systems containing intercropping of Brachiaria decumbens (IB) or Arachis pintoi (IA) were sampled. Total organic carbon (TOC), microbial biomass carbon (MBC) and nitrogen (MBN), microbial activity (C-CO2), metabolic quotient (qCO2), the enzymes dehydrogenase, urease, acid phosphatase and arylsulphatase, arbuscular mycorrhizal fungi (AMF) colonization and number of spores and soil fauna were evaluated. The greatest difference between the management systems was seen in soil organic matter content. The largest quantity of TOC was found in the OC, and the smallest was found in IA. TOC content influenced soil biological parameters. The use of all combined attributes was necessary to distinguish the four systems. Each management presented distinct faunal structure, and the data obtained with the trap method was more reliable than the TSBF (Tropical Soils) method. A canonic correlation analysis showed that Isopoda was correlated with TOC and the most abundant order with OC. Isoptera was the most abundant faunal order in IA and correlated with MBC. Overall, OC had higher values for most of the biological measurements and higher populations of Oligochaeta and Isopoda, corroborating with the concept that the OC is a more sustainable system.
  • Imagem de Miniatura
    Item
    The coffee berry borer: the centenary of a biological invasion in Brazil
    (Instituto Internacional de Ecologia, 2014) Infante, F.; Pérez, J.; Vega, F. E.
  • Imagem de Miniatura
    Item
    Effects of cigarette smoke inhalation and coffee consumption on bone formation and osseous integration of hydroxyapatite implant
    (Instituto Internacional de Ecologia, 2013) Andrade, A. R.; Sant’Ana, D. C. M.; Mendes Junior, J. A.; Moreira, M.; Pires, G. C.; Santos, M. P.; Fernandes, G. J. M.; Nakagaki, W. R.; Garcia, J. A. D.; Lima, C. C.; Soares, E. A.
    The present study aims to assess the effects of cigarette smoke inhalation and/or coffee consumption on bone formation and osseous integration of a dense hydroxyapatite (DHA) implant in rats. For this study, 20 male rats were divided into four groups (n = 5): CT (control) group, CE (coffee) group, CI (cigarette) group and CC (coffee + cigarette) group. During 16 weeks, animals in the CI group were exposed to cigarette smoke inhalation equivalent to 6 cigarettes per day; specimens in the CE group drank coffee as liquid diet; and rats in the CC group were submitted to both substances. In the 6th week a 5 mm slit in the parietal bone and a 4 mm slit in the tibia were performed on the left side: the former was left open while the latter received a DHA implant. As soon as surgeries were finished, the animals returned to their original protocols and after 10 weeks of exposure they were euthanised (ethically sacrificed) and the mentioned bones collected for histological processing. Data showed that exposure to cigarette smoke inhalation and coffee consumption did not interfere in weight gain and that solid and liquid diet consumption was satisfactory. Rats in the CC group showed a decrease in bone neoformation around the tibial DHA implant (31.8 ± 2.8) as well as in boné formation in the parietal slit (28.6 ± 2.2). On their own, cigarette smoke inhalation or coffee consumption also led to diminished bone neoformation around the implant and delayed the bone repair process in relation to the CT group. However, reduction in the bone repair process was accentuated with exposure to both cigarette smoke inhalation and coffee consumption in this study.
  • Imagem de Miniatura
    Item
    What is the influence of ordinary epidermal cells and stomata on the leaf plasticity of coffee plants grown under full-sun and shady conditions?
    (Instituto Internacional de Ecologia, 2010) Pompelli, M. F.; Martins, S. C. V.; Celin, E. F.; Ventrella, M. C.; DaMatta, F. M.
    Stomata are crucial in land plant productivity and survival. In general, with lower irradiance, stomatal and epidermal cell frequency per unit leaf area decreases, whereas guard-cell length or width increases. Nevertheless, the stomatal index is accepted as remaining constant. The aim of this paper to study the influence of ordinary epidermal cells and stomata on leaf plasticity and the influence of these characteristics on stomata density, index, and sizes, in the total number of stomata, as well as the detailed distribution of stomata on a leaf blade. As a result, a highly significant positive correlation (R2 a = 0.767 p ≤ 0.001) between stomatal index and stomatal density, and with ordinary epidermal cell density (R2 a = 0.500 p ≤ 0.05), and a highly negative correlation between stomatal index and ordinary epidermal cell area (R2 a = -0.571 p ≤ 0.001), were obtained. However in no instance was the correlation between stomatal index or stomatal density and stomatal dimensions taken into consideration. The study also indicated that in coffee, the stomatal index was 19.09% in shaded leaves and 20.08% in full-sun leaves. In this sense, variations in the stomatal index by irradiance, its causes and the consequences on plant physiology were discussed.
  • Imagem de Miniatura
    Item
    Transformation of coffee (Coffea Arabica L. cv. Catimor) with the cry1ac gene by biolistic, without the use of markers
    (Instituto Internacional de Ecologia, 2010) De Guglielmo-Cróquer, Z.; Altosaar, I.; Zaidi, M.; Menéndez-Yuffá, A.
    The transformation of coffee plantlets with the cry1ac gene of Bacillus thuringiensis was achieved by biolistic using either the whole pUBC plasmid or only the ubi-cry1ac-nos genetic cassette. The cry1ac gene was inserted into coffee plants in order to confer resistance to the leaf miner Leucoptera coffeella, an insect responsible for considerable losses in coffee crops. Bearing in mind that the genetic cassettes used for this study lack reporter genes and/or selection marker genes, the parameters for the transformation procedure by biolistic were previously standardised with a plasmid carrying the gus reporter gene. The presence of the cry1ac gene in young plantlet tissues was determined by PCR, Southern blot and reverse transcription-PCR. Our results show that the obtainment of viable coffee plantlets, transformed by bombardment with the cry1ac gene and without selection markers nor reporter genes, is feasible.