Unique clones of the pitch canker fungus, <Emphasis Type="Italic">Fusarium circinatum,</Emphasis> associated with a new disease outbreak in South Africa     

Felix F. Fru  Emma T. Steenkamp  Michael J. Wingfield  Quentin C. Santana  Jolanda Roux 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):97-107

Pitch canker of pines is caused by the fungus Fusarium circinatum. In South Africa, this pathogen has mostly been a nursery problem. From 2005, however, outbreaks of pitch canker have been reported from established Pinus radiata and P. greggii in the Western and Eastern Cape Provinces. Most recently, pitch canker-like symptoms were observed on 10-year-old P. greggii trees in a plantation in the midlands of the KwaZulu-Natal (KZN) Province. The aim of this study was to: (i) identify the causal agent of the observed symptoms, (ii) determine the genetic diversity, and (iii) the mode of reproduction of this fungal population. Furthermore, the aggressiveness of isolates from these trees was compared with that of isolates obtained previously from P. patula in South Africa. Isolates from the P. greggii trees in KZN were confirmed as F. circinatum based on both morphology and DNA sequence analyses. Microsatellite marker analyses revealed the presence of five genotypes of F. circinatum, not previously reported from other plantations in South Africa, with one of these genotypes being dominant. These genotypes were all pathogenic to P. patula and P. elliottii. No evidence of sexual reproduction was detected in the KZN population of the fungus. This was consistent with the fact that isolates from P. greggii were all of the MAT-2 mating type, in contrast to previously collected isolates from across South Africa that included both mating types. The results suggest that the outbreak of pitch canker on P. greggii in KZN represents a separate introduction of F. circinatum into the region with important implications for managing the disease.  相似文献   

A hermaphrodite genotype in dioecious papaya progeny: sex reversal or contamination?     

Adriana Azevedo Vimercati Pirovani  Helaine Christine Cancela Ramos  Renato Santa-Catarina  Júlio Cesar Fiorio Vettorazzi  Diego Fernando Marmolejo Cortes  Marcela Santana Bastos Boechat  Dieimes Bohry  Messias Gonzaga Pereira 《Euphytica》2018,214(12):227

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Effects of Lidocaine Infusion during Experimental Endotoxemia in Horses     

J.R. Peiró  P.A. Barnabé  F.A. Cadioli  F.Q. Cunha  V.M.F. Lima  V.H. Mendonça  A.E. Santana  E.B. Malheiros  S.H.V. Perri  C.A.A. Valadão 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2010,24(4):940-948

Background: The clinical efficacy of IV infusion of lidocaine for treatment of equine endotoxemia has not been studied. Hypothesis: Lidocaine infusion after exposure to lipopolysaccharide (LPS) will inhibit the inflammatory response and have inhibitory effects on the hemodynamic and cytokine responses to endotoxemia. Animals: Twelve horses. Methods: Two equal groups (n = 6): saline (GI) and lidocaine (GII). In all animals, endotoxin (500 ng/kg body weight [BW]) was injected intraperitoneally over 5 minutes. Twenty minutes later, animals received a bolus of GI or GII (1.3 mg/kg BW) over 5 minutes, followed by a 6‐hour continuous rate infusion of GI or GII (0.05 mg/kg BW/min). Treatment efficacy was judged from change in arterial blood pressure, peripheral blood and peritoneal fluid (PF) variables (total and differential cell counts, enzyme activities, and cytokine concentrations), and clinical scores (CS) for behavioral evidence of abdominal pain or discomfort during the study. Results: Compared with the control group, horses treated with lidocaine had significantly lower CS and serum and PF tumor necrosis factor‐α (TNF‐α) activity. At several time points in both groups, total and differential cell counts, glucose, total protein and fibrinogen concentrations, and alkaline phosphatase, creatine kinase, and TNF‐α activities were significantly different from baseline values both in peripheral blood and in PF. Conclusions and Clinical Importance: Lidocaine significantly decreased severity of CS and inhibited TNF‐α activity in PF.  相似文献   

Growth performance and gene expression in gilthead sea bream (Sparus aurata) fed microdiets with high docosahexaenoic acid and antioxidant levels          下载免费PDF全文

C. M. Hernández‐Cruz  A. Mesa‐Rodríguez  M. Betancor  A. Haroun‐Izquierdo  M. Izquierdo  T. Benítez‐Santana  S. Torrecillas  J. Roo 《Aquaculture Nutrition》2015,21(6):881-891

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Demographic analysis of the night shark (Carcharhinus signatus, Poey, 1868) in the equatorial Southwestern Atlantic Ocean     

Francisco Marcante Santana  Paulo Duarte-Neto  Rosangela Lessa   《Fisheries Research》2009,100(3):210-214

A demographic analysis of the night shark (Carcharhinus signatus) was carried out to establish the conservation status of this species caught by longlines on oceanic banks off northeastern Brazil. The biological input parameters (age at first maturity, longevity, fecundity and natural mortality) used for the construction of life tables were taken randomly from their respective probability distributions, taking into account the uncertainty of the parameter estimates by employing Monte Carlo simulations. Nine scenarios were generated from natural (M), total (Z), initial (Z₀—corresponding to the first year of life of the cohort) and population equilibrium (Z′) mortality rates. Each scenario was executed 1000 times, varying the vital input rates for the estimation of the demographic parameters (net reproductive rate, R₀; mean generation length, G; and intrinsic rate of population increase, r). Age at first maturity for C. signatus is 10 years; 89.2% of the stock is made up of juveniles, with fishery recruitment beginning at 5 years of age. The scenarios reveal that catches prior to first sexual maturity result in a significant reduction in population (−8.1%/year) and that the population would only support current efforts if the individuals caught are over 10 years of age or if mortality due to fishing efforts corresponded to the equilibrium rate beginning with recruitment at 5 years of age. A low survival rate is estimated for the first year of life. In order for the population to remain in equilibrium with current mortality rates and recruitment age, survival should be around 0.9. The combination of a low initial survival rate, low fecundity, fishery efforts and the large number of juveniles caught indicates that the C. signatus population off northeastern Brazil is being overexploited.  相似文献   

Gram-negative bacterial diversity and evidence of international clones of multidrug-resistant strains in zoo animals     

João Pedro Rueda FURLAN  Micaela Santana RAMOS  Fábio Parra SELLERA  Irys Hany Lima GONZALEZ  Patrícia Locosque RAMOS  Eliana Guedes STEHLING 《Integrative zoology》2024,19(3):417-423

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Canopy characteristics and tillering dynamics of Marandu palisade grass pastures in the rainy–dry transition season          下载免费PDF全文

S. S. Santana  L. F. Brito  M. V. Azenha  A. A. Oliveira  E. B. Malheiros  A. C. Ruggieri  R. A. Reis 《Grass and Forage Science》2017,72(2):261-270

The objective of this study was to evaluate the effect of pasture management during the rainy–dry transition season in Jaboticabal, Brazil, on the structural and tillering characteristics of Marandu palisade grass. The treatments were as follows: 15 cm sward height in the rainy season and ungrazed in the rainy–dry transition season (15/0); 25 cm sward height during the rainy season and fixed stocking rate of 2·5 AU ha^?1 during the rainy–dry transition season (25/2·5); and 35 cm sward height in the rainy season and fixed stocking rate of 2·5 AU ha^?1 in the rainy–dry transition season (35/2·5). There were more herbage mass, stem and dead herbage mass in treatments 25/2·5 and 35/2·5 than 15/0. Tiller appearance rate was greater in treatment 15/0 and tiller mortality rate was higher in treatment 35/2·5 compared to treatment 15/0. Tiller population stability index was 1 in treatment 15/0 and lower in treatment 35/2·5. Although treatment 15/0 showed favourable structural and tillering characteristics, it also has the lowest herbage mass. Treatment 25/2·5 can be regarded as an adequate management strategy for Marandu palisade grass, since it has similar herbage mass and better tillering characteristics than treatment 35/2·5.  相似文献   

Potential of Limestone Tailings for Correction and Fertilization of an Oxisol in the Brazilian Savanna     

Álvaro José Gomes de Faria  Ângela Franciely Machado  Guilherme Nunes Lucena  João Vidal de Negreiros Neto  Jefferson Santana da Silva Carneiro 《Communications in Soil Science and Plant Analysis》2020,51(8):1024-1035

ABSTRACT

Limestone mining industries produce large quantities of by-products that can generate environmental impacts if disposed inappropriately. This study aimed to evaluate the agronomic viability of limestone tailings as soil aciditys and the availability of Ca + Mg in an Oxisol. The experiment was carried out under a randomized complete design, in a 6 × 5 factorial scheme, with four replications. Six sources of limestone [Blended Limestone 1 (BL1), Unblended Limestone 1 (UL1), Blended Limestone 2 (BL2), Unblended Limestone 2 (UL2), Commercial Limestone (CC) and Pure Limestone (PL)] were studied at five application doses (0.0, 0.5, 1.0, 2.0 and 4.0 t ha^?1). During the incubation time of the soil, it was determined the active (pH) and potential acidity (H + Al), as well as the contents of Ca + Mg. It is concluded that the maximum efficiency dose for the limestone sources BL1, UL1, BL2 and UL2 was 4.0 t ha^?1, with responses higher than or equal to commercial limestone. Thus, these sources (BL1, UL1, BL2 and UL2) can be used as soil acidity correctors, since they have adequate reactivity and neutralization power, contributing positively and promisingly in the correction of both active and potential acidity, in addition to increasing the availability of Ca and Mg.  相似文献   

Heterofucan from Sargassum filipendula induces apoptosis in HeLa cells     

Costa LS  Telles CB  Oliveira RM  Nobre LT  Dantas-Santos N  Camara RB  Costa MS  Almeida-Lima J  Melo-Silveira RF  Albuquerque IR  Leite EL  Rocha HA 《Marine drugs》2011,9(4):603-614

Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. Heterofucan SF-1.5v was extracted from the brown seaweed Sargassum filipendula by proteolytic digestion followed by sequential acetone precipitation. This fucan showed antiproliferative activity on Hela cells and induced apoptosis. However, SF-1.5v was not able to activate caspases. Moreover, SF-1.5v induced glycogen synthase kinase (GSK) activation, but this protein is not involved in the heterofucan SF-1.5v induced apoptosis mechanism. In addition, ERK, p38, p53, pAKT and NFκB were not affected by the presence of SF-1.5v. We determined that SF-1.5v induces apoptosis in HeLa mainly by mitochondrial release of apoptosis-inducing factor (AIF) into cytosol. In addition, SF-1.5v decreases the expression of anti-apoptotic protein Bcl-2 and increased expression of apoptogenic protein Bax. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer.  相似文献   

Host preference,acaricides effects and population growth of Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) on white and colored cotton cultivars     

Maurica Fidelis de Santana  Jos Vargas de Oliveira  Mariana Oliveira Breda  Douglas Rafael e Silva Barbosa  Alberto Belo Esteves Filho  Cynara Moura de Oliveira 《Pest management science》2021,77(1):217-223

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