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31.
Potential antagonists were isolated from the epiphytic flora associated with oranges and pome fruit. A total of 1465 microorganisms were tested in a preliminary screening against blue and green moulds on pome and citrus fruit, respectively. Among them, approximately 3% reduced incidence and severity by more than 50% and 4 microorganisms fulfilled the selection criteria of reduction in severity and incidence by 75%. The most effective was a yeast identified as Metschnikowia andauensis, strain NCYC 3728 (PBC-2), isolated from the surface of ‘Bravo de Esmolfe’ apple fruit cultivated in North Portugal. The biocontrol activity of M. andauensis PBC-2 was dependent on its applied concentration. At 5 × 106 cfu/mL incidence (% of infected wounds) and severity (lesion diameter) were reduced by 62 and 70%, respectively and at 1 × 107 cfu/mL, the greatest reduction was achieved, 90% of incidence and 95% of severity. The broad spectrum of action of M. andauensis PBC-2 was evaluated with effective control being achieved against Rhizopus stolonifer, Penicillium expansum and Botritys cinerea, on ‘Rocha’ pears and on different apple cultivars and against Penicillium digitatum and Penicillium italicum on mandarins and oranges. In semi-commercial trials in cold storage, the reduction of blue mould was 90%. Rapid colonization of fresh apple fruit wounds was observed during the first 24 h of cold storage, followed by a significant population increase during the first 15 days of storage and then the population remained stable until the end of storage. 相似文献
32.
Raff MC Stevens CF Roberts K Shatz CJ Roberts K Shatz CJ Newsome WT 《Science (New York, N.Y.)》2004,305(5686):945-946
33.
Keller HU Jorda L Küppers M Gutierrez PJ Hviid SF Knollenberg J Lara LM Sierks H Barbieri C Lamy P Rickman H Rodrigo R 《Science (New York, N.Y.)》2005,310(5746):281-283
The OSIRIS cameras (optical, spectroscopic, and infrared remote imaging system) onboard the European Space Agency's Rosetta spacecraft observed comet 9P/Tempel 1 for 17 days continuously around the time of NASA's Deep Impact mission. The cyanide-to-water production ratio was slightly enhanced in the impact cloud, compared with that of normal comet activity. Dust particles were flowing outward in the coma at >160 meters per second, accelerated by the gas. The slope of the brightness increase showed a dip about 200 seconds after the impact. Dust Afrho values before and long after the impact confirm the slight decrease of cometary activity. The dust-to-water mass ratio was much larger than 1. 相似文献
34.
Colbourne JK Pfrender ME Gilbert D Thomas WK Tucker A Oakley TH Tokishita S Aerts A Arnold GJ Basu MK Bauer DJ Cáceres CE Carmel L Casola C Choi JH Detter JC Dong Q Dusheyko S Eads BD Fröhlich T Geiler-Samerotte KA Gerlach D Hatcher P Jogdeo S Krijgsveld J Kriventseva EV Kültz D Laforsch C Lindquist E Lopez J Manak JR Muller J Pangilinan J Patwardhan RP Pitluck S Pritham EJ Rechtsteiner A Rho M Rogozin IB Sakarya O Salamov A Schaack S Shapiro H Shiga Y Skalitzky C Smith Z Souvorov A Sung W 《Science (New York, N.Y.)》2011,331(6017):555-561
We describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges. 相似文献
35.
Marilyn Holly Carla A. Kirts Yvonne Everett Jan L. Flora David O. Hansen Cornelia Butler Flora John A. Hayward David Haenke Alessandro Bonanno 《Agriculture and Human Values》1988,5(4):57-78
Marilyn Holly is an Associate Professor of Philosophy at the University of Florida. Her special interests include political philosophy, ethics and ecology, Jungian thought, and Native American spirituality in its relation to the environment. She is currently at work on a monograph-length piece on the latter topic. She has taught an undergraduate course in ethics and ecology, and plans to do so again. The following essay emerged from her search for a suitable text for such a course. 相似文献
36.
Proline and light as quality enhancers of rocket (Eruca sativa Miller) grown under saline conditions
Giancarlo Barbieri Antonella BottinoEmilio Di Stasio Simona ValloneAlbino Maggio 《Scientia Horticulturae》2011
Stress conditions experienced during growth may affect plant responses during post-harvest storage and eventually determine the overall quality of commercial products. In this context, we hypothesized that foliar applications of proline during the growth cycle and light exposure during post-harvest storage could be two important modulators of yield and quality parameters of rocket plants exposed to NaCl stress. Dry matter percentage increased upon NaCl treatment. However, fresh weight loss during storage did not change over time as a consequence of salt stress. High salinity (100 mM NaCl) moderately reduced both leaf nitrate (14%) and nitrite (3%) contents. Lipophilic (LAC) and hydrophilic (HAC) antioxidant activities also decreased by 10% at the highest salinization (average of two growth cycles). In contrast, during storage, LAC decreased whereas HAC increased. Proline applications reduced the leaf nitrate content during storage by 16%, increased carotenoids and chlorophyll contents in salinized plants and also increased the ascorbate leaf concentration in both salinized and non-salinzed plants. Light storage enhanced fresh weight loss in contrast to dark storage. However the exposure to light reduced leaf nitrate levels by 7% (average of two growth cycles) and contributed to maintain high leaf ascorbate concentrations over time. 相似文献
37.
Carla C. Eisemberg Mark Rose Benedict Yaru Arthur Georges 《Biological conservation》2011,144(9):2282-2288
Papua New Guinea has astonishing biological and cultural diversity which, coupled with a strong community reliance on the land and its biota for subsistence, add complexity to monitoring and conservation and in particular, the demonstration of declines in wildlife populations. Many species of concern are long-lived which provides additional challenges for conservation. We provide, for the first time, concrete evidence of a substantive decline in populations of the pig-nosed turtle (Carettochelys insculpta); an important source of protein for local communities. Our study combined matched village and market surveys separated by 30 years, trends in nesting female size, and assessment of levels and efficacy of harvest, each of which was an essential ingredient to making a definitive assessment of population trends. Opportunities for an effective response by local communities to these declines needs to consider both conservation and fisheries perspectives because local communities consider the turtle a food resource, whereas the broader global community views it as a high priority for conservation. Our study in the Kikori region is representative of harvest regimes in most rivers within the range of the species in Papua New Guinea, and provides lessons for conservation of many other wildlife species subject to harvest. 相似文献
38.
Raffaele Spinelli Natascia Magagnotti Carla Nati 《European Journal of Forest Research》2011,130(5):737-744
In Italy, poplar plantations represent an important source of wood products, and especially of high-quality veneer logs. These
plantations offer favourable conditions to the introduction of forest mechanisation, and especially easy access and industrial
management. However, owners fear that mechanised log-making may cause value losses, due to poor length measurement, log surface
damage and improper grading. This study compared the performance of manual and mechanised log-making on ten commercial operations,
in order to determine the occurrence and the severity of possible value losses due to product degrade. The study found that
length measurement errors are smaller for mechanised processing, while the frequency and severity of log surface damage are
the same for both treatments. In three cases out of five, mechanised log-making extracted the same value from the stems as
manual log-making: in the remaining two, differences were very small and went opposite directions. Significant differences
were found between operators, stressing the importance of operator skills and motivation. In fact, the log-making specifications
and the pricing structure applied to poplar processing are relatively simple and are unlikely to challenge the ability of
personnel and equipment. At present, most Italian poplar growers are unaware of the potential offered by modern technology,
whose intelligent use would boost value recovery and decrease harvesting cost. Significant benefits may derive from the introduction
of optimised bucking, which may help shifting to a more articulated and rewarding product strategy. 相似文献
39.
Cunha SC Aguero C Damico CB Corgozinho KB Souza HJ Pimenta AL Marassi CD 《Journal of Feline Medicine and Surgery》2011,13(3):205-207
CLINICAL SUMMARY: A 7-month-old female Persian cat presented with gastrointestinal (GI) necrosis and perforation caused by Rhizomucor species. Unfortunately, the cat died of bacterial peritonitis and sepsis before a definitive diagnosis, based on histopathology and fungal culture, was achieved. PRACTICAL RELEVANCE: This appears to be the first reported case of GI disease caused by Rhizomucor species in a cat. Mucorales infections typically cause acute and rapidly progressive disease. As illustrated by this case, clinicians should be alert to the potentially fatal consequences of an opportunistic Rhizomucor species infection in their feline patients. 相似文献
40.