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121.
Thomas Miedaner Angela G. Schilling 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(9):823-830
Fusarium graminearum andF. culmorum are capable of infecting winter cereals at all growth stages. From natural field epidemics of wheat head blight and rye foot rot, three fungal populations were collected with 21, 38 and 54 isolates, respectively; their aggressiveness was analyzed in comparison to collections ofF. graminearum (25 isolates) andF. culmorum (70 isolates) that represent a wide range of geographical locations and host species. All isolates were tested for aggressiveness on young plants of winter rye in the greenhouse and scored for disease severity on a 1–9 scale. Disease ratings of individual isolates ranged from 1.5 to 5.7 indicating quantitative variation of aggressiveness. Genotypic variance was highest in the twoFusarium collections. No substantial difference was found in the amount of genotypic variation betweenF. graminearum andF. culmorum. Individual field populations revealed 57–66% of the total genotypic variation of the collections. This implies a high degree of diversity of aggressiveness within single field populations ofF. graminearum andF. culmorum causing natural epidemics. 相似文献
122.
Angela R. Piergiovanni 《Genetic Resources and Crop Evolution》1998,45(2):97-103
Forty-six accessions of Vigna vexillata from Africa, America and Australia were screened for variability in globulin protein fraction by using SDS-PAGE under reducing and non-reducing conditions. The globulin fraction was composed of several bands clustering in two size fractions, both of which were polymorphic. The high molecular weight fraction was constituted by one or two subunits, while the fraction of lower molecular weight exhibited from two to four bands. Two single types were found within the collection. Due to the observed polymorphism only the subunit at 52 kD was species-specific. Southeastern Africa proved to be the region with the highest diversity for Vigna vexillata. Different frequencies of the globulin patterns were observed between the African and American groups of accessions. No significant differences were found comparing the distribution of the globulin types between the varieties vexillata and angustifolia. 相似文献
123.
Orla M. Mahony Kim E. Knowles Kyle G. Braund Damon R. Averill Jr. Angela E. Frimberger 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1998,12(5):330-337
Five Rottweiler puppies from 3 unrelated litters developed inspiratory stridor at 11–13 weeks of age. Physical examination disclosed tetraparesis in all dogs, and bilateral lenticular cataracts in 4 dogs. Laryngeal examination under light anesthesia showed laryngeal paralysis in all dogs. Electrodiagnostic testing revealed denervation potentials in the distal appendicular muscles of 4 dogs tested and in the intrinsic laryngeal muscles of 2 dogs tested. Motor nerve conduction velocity was slightly low in 1 dog. Neurogenic muscular atrophy was found in distal appendicular muscles (n = 3) and intrinsic laryngeal muscles (n = 2), and degenerative changes were found in peripheral nerves (n = 3) and recurrent laryngeal nerves (n = 2). No abnormalities were detected in the spinal cord, spinal nerve roots, or ganglia of 3 dogs autopsied. The clinical, electrophysiologic, and histopathologic findings support a diagnosis of polyneuropathy and resemble the finding reported in young Dalmatians. Young dogs with laryngeal paralysis should be evaluated neurologically to rule out a more generalized polyneuropathy. The condition is suspected to be hereditary in nature and the prognosis is poor. 相似文献
124.
Pablo Gonzalez-de-Santos Angela Ribeiro Cesar Fernandez-Quintanilla Francisca Lopez-Granados Michael Brandstoetter Slobodanka Tomic Stefania Pedrazzi Andrea Peruzzi Gonzalo Pajares George Kaplanis Manuel Perez-Ruiz Constantino Valero Jaime del Cerro Marco Vieri Gilles Rabatel Benoit Debilde 《Precision Agriculture》2017,18(4):574-614
Feeding the growing global population requires an annual increase in food production. This requirement suggests an increase in the use of pesticides, which represents an unsustainable chemical load for the environment. To reduce pesticide input and preserve the environment while maintaining the necessary level of food production, the efficiency of relevant processes must be drastically improved. Within this context, this research strived to design, develop, test and assess a new generation of automatic and robotic systems for effective weed and pest control aimed at diminishing the use of agricultural chemical inputs, increasing crop quality and improving the health and safety of production operators. To achieve this overall objective, a fleet of heterogeneous ground and aerial robots was developed and equipped with innovative sensors, enhanced end-effectors and improved decision control algorithms to cover a large variety of agricultural situations. This article describes the scientific and technical objectives, challenges and outcomes achieved in three common crops. 相似文献
125.
Caterina DAngelo Angela Casillo Chiara Melchiorre Concetta Lauro Maria Michela Corsaro Andrea Carpentieri Maria Luisa Tutino Ermenegilda Parrilli 《Marine drugs》2022,20(12)
The development of new approaches to prevent microbial surface adhesion and biofilm formation is an emerging need following the growing understanding of the impact of biofilm-related infections on human health. Staphylococcus epidermidis, with its ability to form biofilm and colonize biomaterials, represents the most frequent causative agent involved in infections of medical devices. In the research of new anti-biofilm agents against S. epidermidis biofilm, Antarctic marine bacteria represent an untapped reservoir of biodiversity. In the present study, the attention was focused on Psychrobacter sp. TAE2020, an Antarctic marine bacterium that produces molecules able to impair the initial attachment of S. epidermidis strains to the polystyrene surface. The setup of suitable purification protocols allowed the identification by NMR spectroscopy and LC-MS/MS analysis of a protein–polysaccharide complex named CATASAN. This complex proved to be a very effective anti-biofilm agent. Indeed, it not only interferes with cell surface attachment, but also prevents biofilm formation and affects the mature biofilm matrix structure of S. epidermidis. Moreover, CATASAN is endowed with a good emulsification activity in a wide range of pH and temperature. Therefore, its use can be easily extended to different biotechnological applications. 相似文献
126.
Angela M Lennox 《Veterinary Clinics of North America: Exotic Animal Practice》2007,10(2):533-555
Less common exotic pet mammals are gaining in popularity. The Australian Sugar Glider, African Hedgehog, and prairie dog are seen regularly in exotic animal practices. They are subject to the same types of medical emergencies as more traditional pets, with the unfortunate addition of all too common underlying nutritional and husbandry-related disorders. Emergency stabilization and critical care are important first steps before collection of diagnostic test samples and administration of definitive medical care. 相似文献
127.
Vincent J.M.N.L. Felde Steffen A. Schweizer Danh Biesgen Angela Ulbrich Daniel Uteau Claudia Knief Markus Graf-Rosenfellner Ingrid Kögel-Knabner Stephan Peth 《European Journal of Soil Science》2021,72(2):810-828
Soil microaggregates contain particles of different sizes, which may affect their potential to store organic carbon (OC). A variety of methods can be used to isolate microaggregates from the larger soil structures, among which wet sieving approaches are widely employed. We developed a novel dry crushing method that isolates microaggregates along failure planes due to mechanical stresses rather than hydraulic pressures and compared the mechanical stability, OC contents and microbial community composition between dry-crushed and wet-sieved samples with contrasting clay contents. Dry-crushed samples exhibited a higher stability and bacterial diversity compared to wet-sieved samples. As a result, the dry-crushed microaggregates had different size distributions when analysed dry and after wetting. In the dry state, dry-crushed microaggregates were larger and contained more sand-sized primary particles within the aggregate structures. The wetting of dry-crushed aggregates caused a disintegration of larger microaggregates and sand-sized primary particles into smaller microaggregates that contained finer particles. In the soils with lower clay contents, the diameter of dry-crushed microaggregates was 40 μm larger due to more sand-sized primary particles remaining within the aggregates. Depending on how much volume in microaggregates is occupied by large primary particles, the OC concentration increased in the soil with higher clay content. Wet-sieved size fractions also showed a similar pattern of OC distribution, whereas more primary particles were observed outside of aggregates. Wet sieving approaches disperse the soil into OC-rich aggregates and might be preferable if OC dynamics are investigated. Differences in bacterial community composition in dependence on clay content were more pronounced in dry-crushed microaggregates. If intact aggregate architectures are of interest for the isolation of soil structural units, the presented dry crushing method might provide an advantageous alternative that also better preserves bacterial diversity. 相似文献
128.
Angela R. Piergiovanni 《Genetic Resources and Crop Evolution》2013,60(1):325-333
The increasing consumers’ request for new speciality wheat derivatives and the possible widening of marketing opportunities is giving to both landraces and old varieties, new chance of on farm survival providing a low cost way to safeguard these important genetic resources. A farmer’s consortium acting in north-western Italy, is attempting the introduction of some old bread wheat landraces in marginal environments of Piedmont and Liguria regions. The reason of this attempt is the local market demand of old bread varieties suitable for the preparation of traditional cakes and biscuits. Three Italian bread wheat landraces, a mixture of durum and bread wheat landraces and three modern varieties were evaluated. The entries were cropped in Val Borbera and Val d’Aveto (Piedmont and Liguria region, respectively) in the same growing season (2009–2010). The high variation of gliadin profile detected within the landraces indicates that all have retained the genetic heterogeneity typical of the old wheat landraces. In consequence of the health-promoting effects of whole grain consumption, eleven nutritional and technological traits of whole flours were investigated. The analysis of collected data revealed appreciable differences among the flours obtained from the landraces and the modern varieties. These differences can be mainly attributed to the intensive breeding carried out on bread wheat in the last century. The results of this study suggest that the old bread wheat landraces could have good chance of survive on farm when their characteristics fulfil the requirements of local communities. 相似文献
129.
Antonucci Francesca Menesatti Paolo Iori Angela Pallottino Federico D’Egidio Maria Grazia Costa Corrado 《植物病害和植物保护杂志》2013,120(5-6):205-208
Journal of Plant Diseases and Protection - Thermal imaging is a potential remote sensing tool for estimating fungal wheat diseases. This study for the first time investigated the suitability of... 相似文献
130.
Shi Liu Peng Gao Qianglong Zhu Feishi Luan Angela R. Davis Xiaolu Wang 《Breeding Science》2016,66(2):244-259