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151.
Mingming Yang Dmitri V. Mavrodi Olga V. Mavrodi Linda S. Thomashow David M. Weller 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(3):683-693
Four Neofabraea species are responsible for bull’s eye rot, which is an important postharvest disease of apples and pears. The species diversity of its causal agents in Europe has not been thoroughly explored using molecular genetic methods. Eighty-one Neofabraea isolates were obtained mostly from apples with bull’s eye rot symptoms in the Czech Republic over a two year period. The isolates were identified using PCR fingerprinting and DNA sequencing of the ITS rDNA region, the mitochondrial SSU rDNA and the β-tubulin and EF1α genes. The most common species was N. alba (89 %), followed by N. perennans (5 %) and N. kienholzii (5 %). This is the third published record of N. kienholzii in Europe. The species identity of the isolate CPPF507, which was placed close to N. kienholzii, remains unclear. EF1α was shown to be a suitable marker for the identification of species of the genus Neofabraea and was comparable to the previously used β-tubulin gene. Furthermore, the aggressiveness of individual species was compared and species distribution across Europe was summarized. N. perennans and isolate CPPF507 proved to be the most aggressive, whereas the least aggressive was N. kienholzii. Two N. alba isolates isolated from symptomless apple fruits and leaves were pathogenic to apples in the infection tests. 相似文献
152.
153.
Linda L. Chinangwa Andrew S. Pullin Neal Hockley 《Journal of Sustainable Forestry》2017,36(4):338-357
Forest co-management programs aim to conserve forest resources. However, there is little evidence of its effectiveness. We assess the impact of co-management approaches on forest conditions in Zomba-Malosa and Ntchisi forest reserves in Malawi using a multiple-site, plot-based, and control-intervention design. We used tree density and species richness as indicators of forest condition. Evidence of human activities was used as potential indicators of current and future impacts. Local peoples’ perceptions of the impact of co-management on forest were also sought to validate the inventory information. Co-managed plots have higher tree density than state managed plots. Indicators of human activities including felled trees, farming and settlement plots, and grazing, were observed in both co-managed and state managed forest block. A majority of respondents, 84% in Zomba-Malosa and 73% in Ntchisi, perceive the co-management program to have a positive impact on forest conditions against a general worsening trend. Despite having a potential to improve forest conditions, the findings suggest that the outcomes of a co-management may vary depending on preexisting conditions and how communities understand and interpret the program. Hence, programs should not be implemented as a universal package. Furthermore, even with method triangulation, the lack of baseline data limited the quantification impacts; hence, integration of participatory research into the program is recommended. 相似文献
154.
Jaana Laurila Asko Hannukkala Johanna Nykyri Miia Pasanen Valérie Hélias Linda Garlant Minna Pirhonen 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(2):249-262
Biochemical characterisation of Dickeya strains isolated from potato plants and river water samples in Finland showed that the majority of the strains were biovar 3. They thus resembled the strains recently isolated from potato in the Netherlands, Poland and Israel and form a new clade within the Dickeya genus. About half of the Finnish isolates resembling strains within this new clade were virulent and caused wilting, necrotic lesions and rotting of leaves and stems. Similar symptoms were caused by D. dianthicola strains isolated from one potato sample and from several river water samples. Frequently, the rotting caused by the Dickeya strains was visible in the upper parts of the stem, while the stem base was necrotic from the pith but hard and green on the outside, resulting in symptoms quite different from the blackleg caused by Pectobacterium atrosepticum. The presence of Dickeya in the symptomatic plants in the field assay was verified with a conventional PCR and with a real-time PCR test developed for the purpose. The virulent Dickeya strains reduced the yield of individual plants by up to 50% and caused rotting of the daughter tubers in the field and in storage. Management of Dickeya spp. in the potato production chain requires awareness of the symptoms and extensive knowledge about the epidemiology of the disease. 相似文献
155.
Linda L. KERLEY 《Integrative zoology》2010,5(4):390-396
This paper is a review of the history, development and efficacy of using dogs in wildlife studies and considers the use of dogs in the research and conservation of wild tigers (Panthera tigris Linnaeus, 1758). Using scat detection dogs, scent-matching dogs, law enforcement detection dogs and protection dogs are proven methods that can be effectively used on tigers. These methods all take advantage of the dog's extremely evolved sense of smell that allows them to detect animals or animal byproducts (often the focus of tiger studies). Dogs can be trained to communicate this information to their handlers. 相似文献
156.
157.
Signatures of adaptation to obligate biotrophy in the Hyaloperonospora arabidopsidis genome 总被引:2,自引:0,他引:2
Baxter L Tripathy S Ishaque N Boot N Cabral A Kemen E Thines M Ah-Fong A Anderson R Badejoko W Bittner-Eddy P Boore JL Chibucos MC Coates M Dehal P Delehaunty K Dong S Downton P Dumas B Fabro G Fronick C Fuerstenberg SI Fulton L Gaulin E Govers F Hughes L Humphray S Jiang RH Judelson H Kamoun S Kyung K Meijer H Minx P Morris P Nelson J Phuntumart V Qutob D Rehmany A Rougon-Cardoso A Ryden P Torto-Alalibo T Studholme D Wang Y Win J Wood J Clifton SW Rogers J Van den Ackerveken G Jones JD 《Science (New York, N.Y.)》2010,330(6010):1549-1551
Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy. 相似文献
158.
Rosanna Marsella Linda Messinger Sonja Zabel Rod Rosychuck Craig Griffin Patti Orozco Cronin Gil Belofsky Julie Lindemann Dean Stull 《Veterinary dermatology》2010,21(1):50-57
Canine atopic dermatitis (AD) is common and new therapies are beneficial. This multicentric, randomized, double-blind, placebo-controlled study tested the efficacy of Actinidia arguta (hardy kiwi) (EFF1001) in dogs with mild/moderate AD. The study was divided into two stages. Stage 1 lasted 6 weeks. In the first 2 weeks prednisolone [days 1–3: 0.2 mg/kg twice daily (BID), days 4–14: 0.2 mg/kg every other day (EOD)] was administered. Responsive dogs were placed on prednisolone 0.2 mg/kg EOD + assigned test article [either placebo or EFF1001 (30 mg/kg)] once daily for 4 weeks. Stage 1 responders were advanced to stage 2, which involved 4 weeks of just EFF1001. Clinicians scored lesions using Canine Atopic Dermatitis Extent and Severity Index (CADESI) and owners scored pruritus using a Pruritus Visual Analogue Scale. Seventy-seven dogs were enrolled, 76 were randomized on day 14, and 57 (57/76 = 75%) completed stage 1 (27 in EFF1001 and 30 in placebo). At the end of stage 1, 35 of 57 dogs (35/57 = 61%) responded (18 in EFF1001 and 17 in placebo) and advanced to stage 2. At completion of stage 1, CADESI scores did not significantly differ between groups while pruritus decreased in EFF1001 group and approached significance. At completion of stage 2, 19 dogs (19/35 = 54%) responded (15/19 = 79% had received EFF1001 and 4/19 = 21% placebo in stage 1). After completing stage 2, dogs placed on EFF1001 throughout the study were 3.5 times more likely to either maintain or improve scores than those that started it in stage 2. It is concluded that EFF1001 is beneficial adjunctive therapy after prolonged use. 相似文献
159.
A sample of fourteen horse rugs and two saddle blankets stored in south western Sydney, Australia, an area of known high dust mite prevalence in the human environment, were analysed for the presence of house dust mites. Dust samples from the rugs, blankets and 16 control sites were collected using a vacuum cleaner with a modified attachment and filter. Dust mites were extracted using an adapted floatation technique. Eight rugs and all control samples were positive for mites, which were confirmed to be house dust mites of the genus Dermatophagoides. This study confirms that exposure to house dust mites from horse rugs can occur, indicating that house dust mite allergen reactivity on intradermal and serum allergy testing in atopic horses may represent true dust mite hypersensitivity. Nevertheless, quantification studies will be necessary to ensure that there is adequate mite exposure for development of hypersensitivity, and further evaluation of immunological responses, avoidance and provocation, and specific immunotherapy are required to confirm the clinical relevance. To the authors’ knowledge, this is the first study to document the presence of house dust mites in the equine environment. 相似文献
160.