First report of Phytophthora boehmeriae on black wattle in Brazil     

A. F. Dos Santos  E. D. M. N. Luz  J. T. De Souza 《Plant pathology》2006,55(6):813-813

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OC4Influence of Seminal Plasma Added to Highly Diluted Semen on Sperm Motility of Young Boar Feed with Selenium and Vitamin E     

F Centurión  S Echeverría  N Canul  R Ake  M Alfaro  R Santos  L Sarmiento 《Reproduction in domestic animals》2006,41(S2):103-104

High dilution rates have been documented as detrimental for boar spermatozoa, shortening their lifespan (Centurion et al. 2003, Biol Reprod 69: 640–646). Addition of seminal plasma (SP) to semen extenders, or selenium (Se) and vitamin E (VE) in diet of boars could increase motility of highly diluted spermatozoa (HDS). The aim of this work was to evaluate the effect of seminal plasma on sperm motility of HDS from boars feed with Se and VE. Sixteen 12 month-old boars were designed to one of four dietary treatments: (i) control, Se 0 ppm–VE 0 IU/kg; (ii) Se 0–VE 250; (iii) Se 0.5–VE 250 and (iv) Se 0.5–VE 0. Boars were treated for 8 weeks before semen collection. Sperm rich fractions from each boar were diluted to 5 × 10⁶ sperm/ml in PBS medium and incubated at 37°C with or without 10% SP. The measurements were done at 0, 2 or 5 h. Data were analyzed as a mixed model for a factorial design [2 (Se) × 2 (VE) × 2 (SP) × 3 (h)]. Percentage of sperm motility (PSM) increases significantly (p < 0.001) with addition of Se (81.3 ± 1.52), VE (81.0 ± 1.62) and SP (81.5 ± 1.57) vs control (73.4 ± 1.61). There was significant interaction Se × VE (p < 0.001) and Se × VE × SP (p < 0.05) in PSM. However, PSM was affected significantly by time (0 h 83.4 ± 1.92; 2 h 80.7 ± 1.92 and 5 h 67.9 ± 1.92; p < 0.001). There was significant interaction SP × Time (p < 0.05) in PSM. These results indicate that Se, VE and SP improve seminal viability. Addition of 10% of SP maintains PSM at least during 5 hours.  相似文献   

Alternative low doses and routes of administering a prostaglandin F2�� analogue to induce luteolysis in Nelore cows     

Cezinande Meira  Valsair Matos Pessoa  Jo?o Carlos Pinheiro Ferreira  Gustavo Henrique M. Araujo  Marilu M. Gioso  Sony Dimas Bicudo  Eunice Oba  Cassia Orlandi 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):387-390

The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2α analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows.  相似文献   

Phenotypic characterisation of Phaeoacremonium and Phaeomoniella strains isolated from grapevines: enzyme production and virulence of extra-cellular filtrate on grapevine calluses     

Conceição Santos  Sílvia Fragoeiro  Helena Valentim  Alan Phillips 《Scientia Horticulturae》2006

Extra-cellular enzyme production of different Phaeoacremonium spp. and Phaemoniella chlamydospora isolates were used to assay the possibility of inter-specific characterisation. Isolates of Phaeoacremonium aleophilum, Phaeoacremonium angustius, P. viticola and Ph. chlamydospora were grown on solid media and the activities of extra-cellular amylases, lipases, proteases, cellulases, xylanases, laccase, polygalacturonase, pectate lyase, lignin peroxidase, manganese peroxidase, urease and chitinase were assayed. Phaeoacremonium species showed activities of a larger number of enzymes and also enzyme activity was frequently higher suggesting that Phaeoacremonium can be more virulent. To assay if the produced extra-cellular enzymes could reflect the virulence capacity of the two genera, calluses of Vitis vinifera L. (cvs. Baga and Maria Gomes) and of a rootstock (R3309) were inoculated with filtrated culture liquid medium of three isolates of Ph. chlamydospora and one of P. angustius. Filtrates from all strains decreased callus growth and membrane integrity, while soluble protein content of calluses decreased with the strains CAP 054 and 1AS. P. angustius (CAP 054) induced the more severe symptoms in all genotypes. Water content decreased together with an increase of osmolality in both cultivars but not in rootstock suggesting that osmorregulatory capacity is more affected in cultivars. Data show that: (1) Phaeoacremonium and Phaeomoniella genera have different patterns of extra- cellular enzymatic production; (2) these fungi produce extra-cellular compound(s) that induce(s) senescence symptoms in plant cells inhibiting callus proliferation; (3) among the strains tested in plant calluses the most virulent isolate (CAP 054) also produced higher amounts of some extra-cellular enzymes; (5) rootstock calluses were less sensitive to inoculation than grapevine calluses.  相似文献   

Effects of deficit irrigation strategies on cluster microclimate for improving fruit composition of Moscatel field-grown grapevines   总被引：1，自引：0，他引：1  

Tiago Pedreira dos Santos  Carlos M. Lopes  M. Lucília Rodrigues  Claudia R. de Souza  Jorge M. Ricardo-da-Silva  João P. Maroco  João S. Pereira  M. Manuela Chaves 《Scientia Horticulturae》2007

The grapevine plays a very important role in the economic, social and cultural sectors of many regions; however vineyards are often grown in regions under stressful conditions and thus they are vulnerable to climate change. The objective of this research was to investigate the effect of partial root-zone drying (PRD) irrigation on vine water relations, vegetative growth, plant microclimate, berry composition and yield components, compared to conventional deficit irrigation (DI, 50% ETc), full irrigation (FI, 100% of ETc) and non-irrigated vines (NI). The study was undertaken in mature ‘Moscatel’ grapevines (Vitis vinifera L.) grown in Pegões, South of Portugal. Compared to the other irrigated treatments, PRD vines showed a better microclimate at the cluster zone with higher incident photosynthetic photon flux density (PPFD). Within the more open canopies of NI and PRD treatments, berry temperatures were higher than those of denser ones (DI and FI). Compared to the conventional irrigation technique the better microclimate observed in PRD vines was a consequence of a reduction in vine growth, where lower values of leaf layer number, leaf area, canopy wideness, water shoots and shoot weight were observed. In PRD vines we observed a tendency to a development of a deeper root system, while DI and FI showed a more homogeneous root distribution throughout the different soil layers. PRD showed an improvement in berry quality with higher values of flavour precursors, and total phenols concentration without any significant yield reduction compared to DI and FI.  相似文献   

Molecular analysis of resistance mechanisms to Orobanche cumana in sunflower     

P. Letousey  A. de Zélicourt  C. Vieira Dos Santos  S. Thoiron  F. Monteau  P. Simier  P. Thalouarn  P. Delavault 《Plant pathology》2007,56(3):536-546

Resistance to the dicotyledenous parasite Orobanche cumana in sunflower is characterized by a low number of parasitic attachments and a confinement of the parasite in host tissues leading to its necrosis. To help understand what determines such resistance mechanisms, molecular, biochemical and histological approaches were employed before (early response) and after (late response) attachment of the broomrape parasite to susceptible (2603) and resistant (LR1) sunflower genotypes. The expression patterns of 11 defence-related genes known to be involved in different metabolic pathways (phenylpropanoids, jasmonate, ethylene) and/or in resistance mechanisms against microorganisms were investigated. RT-PCR and cDNA blot experiments revealed that the resistant genotype exhibited a stronger overall defence response against O. cumana than the susceptible one, involving marker genes of the jasmonate (JA) and salicylic acid (SA) pathways. Among them, the SA-responsive gene, def. (defensin), appeared to be characteristic of LR1 sunflower resistance. However, no JA accumulation and similar SA contents (250–300 ng g⁻¹ FW) were measured by GC/MS in both genotypes, parasitized or not. In addition, three cDNAs, isolated by a suppression-subtractive hybridization, were shown to be strongly induced only in the resistant genotype 8 days post-inoculation, when the first O. cumana attachments occurred. These genes, putatively encoding a methionine synthase, a glutathione S-transferase and a quinone oxidoreductase, might be involved in detoxification of reactive oxygen species, suggesting the occurrence of an oxidative burst during the incompatible interaction. Finally, host cell-wall modifications leading to parasite-confinement were correlated with more intense callose depositions in the resistant genotype, concomitant with over-expression of the callose synthase cDNA HaGSL1 .  相似文献   

Evaluation of hematological,biochemical and oxidative stress profile in calves under propofol anesthesia     

Lima  Pedro Paulo Arcanjo  Narciso  Luis Gustavo  Alcindo  Jefferson Filgueira  Deschk  Maurício  Ciarlini  Paulo Cesar  dos Santos  Paulo Sérgio Patto  de Almeida  Breno Fernando Martins 《Veterinary research communications》2022,46(1):27-35

Veterinary Research Communications - Propofol is a widely used drug in veterinary medicine to induce anesthesia; as well as the chosen compound for protocols of intravenous anesthesia. The present...  相似文献   

Dynamics of natural infection by Toxoplasma gondii in goat herds in the semiarid region of northeastern Brazil: transitional antibody observation     

Sousa  Larissa Nascimento  Batista  Samira Pereira  Silva  Samara Santos  da Silva  Rômulo Fylipe  Sarmento  Wlysse Ferreira  Mota  Rinaldo Aparecido  Brasil  Arthur Willian Lima  Amaku  Marcos  Feitosa  Thais Ferreira  Vilela  Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515

Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the...  相似文献   

温度对大叶桃花心木(Swietenia macrophylla King)幼苗叶片的光合影响   总被引：2，自引：0，他引：2  

张成军  祖元刚  郭佳秋 《林业研究》2003,14(2):130-134

本文研究了大叶桃花心木（Swietenia macrophylla King）一年生幼苗在经过夜温处理后的光响应曲线和在饱和光强下的CO2反应曲线.结果表明:在大气CO2浓度下,叶片的最佳光合作用温度在25-31℃之间,而在饱和CO2浓度下为31-35℃.在25℃以下光合速率开始降低,主要是由于羧化效率的降低,而当温度超过31℃时,光合速率下降,是因为羧化效率的降低和呼吸速率的增加.CO2浓度对光合的促进作用在低温下受到抑制,这意味着未来在CO2浓度增高的情况下,高浓度的CO2对热带常绿植物光合的促进在冬天低温情况下表现不十分明显.图4参23.  相似文献   

Intermediate reactive oxygen and nitrogen from macrophages induced by Brazilian lichens     

Santos LC  Honda NK  Carlos IZ  Vilegas W 《Fitoterapia》2004,75(5):473-479

The activity of ten compounds isolated from Brazilian lichen over the release of hydrogen peroxide and nitric oxide was evaluated in the culture of peritoneal macrophage cells from mice. Salazinic, secalonic A and fumarprotocetraric acids were the compounds that induced the greatest release of H2O2, whereas 12R-usnic and diffractaic acids induced the release of NO. These results indicate that lichen products have potential immunological modulating activities.  相似文献