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621.
622.
First detection of Neoscytalidium dimidiatum associated with canker disease in Egyptian Ficus trees 下载免费PDF全文
In September 2013, a canker disease of Ficus nitida and F. benjamina was reported for the first time in Assiut governorate, Egypt. Infected samples were collected from various locations. Pure cultures of a fungus were isolated on potato dextrose agar at 25°C from diseased plants. Morphological investigation and DNA sequencing showed that the causal agent was Neoscytalidium dimidiatum. A pathogenicity test conducted using 2‐year‐old plants of each host gave 70%–80% infection, and the pathogen was reisolated from the inoculated plants. A pure culture of N. dimidiatum was deposited in the culture collection of the Assiut University Mycological Centre (AUMC) under the code AUMC 9293 and the ITS sequence was placed in NCBI under accession number KX985929 . 相似文献
623.
Risky Ayu Kristanti Tony Hadibarata Dunia A. Al Farraj Mohamed Soliman Elshikh Roua M. Alkufeidy 《Water, air, and soil pollution》2018,229(10):324
This aim of the study is to investigate a halophilic bacterium Hortaea sp. B15, isolated from petroleum-contaminated soil for biodegradation of phenanthrene. Hortaea sp. B15 has the ability to completely degrade phenanthrene (100 mg/L) under salinity 10% within 1-week incubation. The metabolitic product of phenanthrene was identified and assayed by using ultraviolet-visible spectrophotometer and mass spectral analysis. Result revealed that Hortaea sp. B15 metabolized phenanthrene to form 9,10-phenanthrene quinone, salicylic acid, and gentisic acid. Hortaea sp. B15 has an efficient utilization of phenanthrene in high-saline liquid medium. All the results indicated that the fungus has a promising application for the study of high-molecular-weight PAH biodegradation and contaminated saline-alkali soil bioremediation. 相似文献
624.
叶菜类蔬菜施用不同氮磷钾复混肥和硫肥的效应研究 总被引:11,自引:2,他引:9
叶菜类蔬菜施用不同氮磷钾复混肥和硫肥的肥效试验结果表明,以NH4NO3为氮源配制的叶菜专用BB肥的增产效果高于以尿素配制的叶菜专用BB肥,以尿素配制的叶菜专用BB肥加硫肥的肥效与K2SO4复合肥(15-15-15-S)相近,而KCl复合肥(15-15-15-Cl)的肥效明显较差且叶菜品质有所下降。各种复混肥配合施用硫肥均可提高肥料的增产效果;菜心施硫效果优于白菜。不同复混肥中,叶菜专用BB肥加硫肥 相似文献
625.
OBJECTIVE: To provide information on the clinical features, diagnosis and treatment of bacterial septic arthritis in dogs. DESIGN: A retrospective study examining case records of all dogs diagnosed with bacterial septic arthritis at Murdoch University Veterinary Hospital between 1988 and 1997. RESULTS: Nineteen dogs were diagnosed with bacterial septic arthritis, which most commonly occurred after surgery involving the stifle joint. Haematogenous infection occurred in only five dogs. Diagnosis was based on clinical signs, joint fluid analysis, radiography, microbiology and/or response to treatment. Chronic lameness was the most common problem at presentation. Analysis of joint fluid invariably revealed large number of nucleated cells, which consisted primarily of neutrophils. In all but one case the neutrophils were nondegenerate. Culture of joint fluid was frequently successful. Staphylococcus spp were the most common bacteria isolated. Treatment involved antimicrobial drugs only in five dogs. Other dogs received antimicrobial drugs in combination with surgical procedures such as joint lavage and removal of nonabsorbable suture material (eight), arthrodesis (two) or amputation (one). Two dogs were euthanased. Most dogs responded well to treatment and were free of signs of septic arthritis at follow-up. CONCLUSION: Bacterial septic arthritis may often be mild and manifest as chronic lameness. Analysis of joint fluid will detect an inflammatory arthropathy but the presence of toxic neutrophils should not be relied on as an indicator of sepsis. Culture of infected joint fluid is likely to be successful if antimicrobials are not given prior to collection and if the sample is inoculated into enrichment broth. Treatment should involve antimicrobial drugs, open-joint lavage and removal of joint prostheses if the infection is associated with previous surgery. 相似文献
626.
After the evaluation of numerous accessions of primitive wheats for yield components and morphophysiological traits related
to drought tolerance (e.g., maintenance of high relative water content, RWC; photochemical quenching of chlorophyll fluorescence,
qQ; and chlorophyll loss, chl, under moisture stress conditions), several accessions belonging to three species (Triticum
dicoccum, T. polonicum, and T. carthlicum) were crossed with the improved durum wheat varieties Cham 1 and Om Rabi 5. A direct
selection (F2 progeny) for yield and an indirect physiological trait were applied on interspecific T. durum x T. dicoccum, T. durum x T.
polonicum, and T. durum x T. carthlicum populations. Divergent selection was applied to validate the possible use of morphophysiological
traits (root parameters, RWC, photochemical quenching, proline content, and carbon isotope discrimination) in selection, and
to evaluate the resulting effects on yield. Heritability and selection response of these traits has been evaluated, and the
impact of divergent selection for morphological and agronomic characters was studied under field conditions. The divergent
populations were evaluated under different environmental conditions in France, Syria, and Yemen. Selection for morphophysiological
traits related to moisture stress, such as root parameters, RWC and carbon isotope discrimination was possible due to high
h2 values and effective, resulting in high genetic gains. However, the effect of selection for these traits on yield stability
needs to be further studied. Furthermore, a modified bulk method (F2 'progeny method') was developed. Direct selection for grain yield per plant in F2 was carried out and yield per line in F3 was evaluated under contrasting environmental conditions in France, Syria, and Tunisia. Results revealed that some F3 lines were higher yielding than the improved durum wheat varieties Cham 1 and Om Rabi 5 under both stressed (Aleppo) and
favourable (Montpellier) environmental conditions. Lines were evaluated in preliminary yield trials at Montpellier (France),
Aleppo (Syria), and Constantine (Algeria). Results indicated that the use of related species combined with the use of the
modified bulk breeding method is promising not only for increasing durum wheat yield in drought prone environments, but also
for improving durum wheat yield stability across contrasting environments. Results of both breeding strategies are presented,
and the potential advantages of using related tetraploid species in durum wheat breeding for drought tolerance are discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
627.
Hollow silica and silica-polymer spheres with diameters between 720 and 1000 nanometers were fabricated by consecutively assembling silica nanoparticles and polymer onto colloids and subsequently removing the templated colloid either by calcination or decomposition upon exposure to solvents. Scanning and transmission electron microscopy images demonstrate that the wall thickness of the hollow spheres can be readily controlled by varying the number of nanoparticle-polymer deposition cycles, and the size and shape are determined by the morphology of the templating colloid. The hollow spheres produced are envisioned to have applications in areas ranging from medicine to pharmaceutics to materials science. 相似文献
628.
Paloma Feyjoo Rodrigo Riera Beatriz C. Felipe Alí Skalli Eduardo Almansa 《Aquaculture International》2011,19(1):193-204
Ammonia and nitrite are among the most important water quality parameters. The aim of this study was to determine the acute
toxicity of unionized ammonia and nitrite on newly hatched Octopus vulgaris paralarvae. Concretely, survival, feeding and chromatophore activity were examined under different NH3 and NO2
− concentrations. The median lethal concentration (LC 50) determined for 24 h was 10.7 ppm for NH3 and 19.9 ppm for NO2
−. Based on these results, a concentration range was chosen to test the effect of this environmental contaminants in feeding
and chromatophore activity (range between 2.5 and 20 ppm for feeding and 10 and 30 ppm for chromatophore activity), resulting
in modifications in both parameters. In fact, a significant decrease (P < 0.05) in Artemia nauplii consumption by the paralarvae was observed with an increase in NH3 and NO2
−. Similarly, the chromatophore activity was also affected by concentration of these contaminants, with decreasing response
(P < 0.05) when submitted to stressful situations, as the ammonia and nitrite concentration was increased. 相似文献
629.
Jose Luis Sánchez‐Salgado Mohamed Alí Pereyra Concepción Agundis Oscar Vivanco‐Rojas Claudia Sierra‐Castillo Juan José Alpuche‐Osorno Edgar Zenteno 《Aquaculture Research》2017,48(8):4001-4011
Several lectins have been found in crustaceans, and it has been suggested that they play roles in cell signalling, cell–cell interaction, protein synthesis and pathogen recognition. These functions are performed through their specificity for carbohydrates. This review analyses the carbohydrate specificity, tissue distribution and participation in the immune responses of lectins in crustaceans. Furthermore, we explore some data showing that lectin expression seems to be stimulated by pathogens, favouring crustacean survival. 相似文献
630.