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531.
García-Sánchez M. Pino González-Ávila Sergio Solana-Gutiérrez Joaquín Popa Marius Jurj Ramon Ionescu Georgeta Ionescu Ovidiu Fedorca Mihai Fedorca Ancuta 《Landscape Ecology》2022,37(5):1311-1329
Landscape Ecology - Romania is currently one of the best-connected landscapes, with high-quality habitats and a high density of brown bears. However, regional development measures are needed for... 相似文献
532.
533.
Yeung T Gilbert GE Shi J Silvius J Kapus A Grinstein S 《Science (New York, N.Y.)》2008,319(5860):210-213
Electrostatic interactions with negatively charged membranes contribute to the subcellular targeting of proteins with polybasic clusters or cationic domains. Although the anionic phospholipid phosphatidylserine is comparatively abundant, its contribution to the surface charge of individual cellular membranes is unknown, partly because of the lack of reagents to analyze its distribution in intact cells. We developed a biosensor to study the subcellular distribution of phosphatidylserine and found that it binds the cytosolic leaflets of the plasma membrane, as well as endosomes and lysosomes. The negative charge associated with the presence of phosphatidylserine directed proteins with moderately positive charge to the endocytic pathway. More strongly cationic proteins, normally associated with the plasma membrane, relocalized to endocytic compartments when the plasma membrane surface charge decreased on calcium influx. 相似文献
534.
Summary In trials with potato tubers infected with tobacco rattle virus (TRV), symptoms of spraing in cvs Bellona, King Edward, Maris
Bard, Matilda, Sv 82146 and Sv 82149 increased during storage when the tubers were cut. Storage of intact tubers at a constant
temperature of 9°C or at fluctuating temperatures (2 weeks at 18°C, 2 weeks at 9°C and 2 weeks at 18°C) did not increase the
frequency of symptoms. 相似文献
535.
Debasis MITRA Sergio DE LOS SANTOS-VILLALOBOS Fannie Isela PARRA-COTA Ana Mara Garcia MONTELONGO Erika Lorena BLANCO Vanessa L. LIRA Adeyemi N. OLATUNBOSUN Bahman KHOSHRU Rittick MONDAL Parameswaran CHIDAMBARANATHAN Periyasamy PANNEERSELVAM Pradeep K. DAS MOHAPATRA 《土壤圈》2023,33(2):268-286
Various microorganisms live in association with different parts of plants and can be harmful, neutral, or beneficial to plant health. Some microbial inhabitants of plants can control plant diseases by contesting with, predating on, or antagonizing plant pathogens and by inducing systems for plant defense. A range of methods, including plant growth-promoting microorganisms(PGPMs) as biological control agents(BCAs)(BCA-PGPMs) are used for the biological management and control of plant pathogens. S... 相似文献
536.
Todaro A Cavallaro R Argento S Branca F Spagna G 《Journal of agricultural and food chemistry》2011,59(20):11244-11248
In this study the catecholase and cresolase activities of eggplant polyphenol oxidase (PPO) were investigated. Enzyme activity was determined by measuring the increase in absorbance using catechol as substrate and 3-methyl-2-benzothiazolinone hydrazone (MBTH) as coupled reagent. The effects of substrate specificity, heat inactivation, temperature, pH, and inhibitors were investigated to understand the enzymatic alteration of ready-to-eat preparations. Browning of vegetables was determined through a colorimeter. Decrease of lightness (L*) and increase of color difference values (ΔE*) were correlated with tissue browning. Antibrowning agents were tested on PPO under the same conditions. The enzyme activity was strongly inhibited by 0.4 M citric acid. Under natural pH conditions, the enzyme was also inhibited by tartaric acid and acetic acid. All of the results were used to understand the best conditions for food transformation (ready-to-eat and grilled eggplant slices). 相似文献
537.
Amplified fragment length polymorphism for variety identification and genetic diversity assessment in oleander (Nerium oleander L.) 总被引:1,自引:0,他引:1
Ezio Portis Cinzia Comino Anna Lenzi Piero Lombardi Romano Tesi Sergio Lanteri 《Euphytica》2004,136(2):125-137
Oleander is a Mediterranean evergreen shrub found along watercourses, gravelly places and damp slopes. It is grown widely
as an ornamental for its abundant and long-lasting flowering as well as its moderate hardiness. Genetic relatedness among
71 accessions, including commercial varieties, different sources of the same varieties, and selections from the wild were
investigated using amplified fragment length polymorphism (AFLP). Nine primer combinations yielded a total of 603 bands of
which 241 were polymorphic. Genetic similarities among accessions were calculated according to Jaccard's Similarity Index
and used to construct a dendrogram based on the unweighted pair group method using arithmetic averages. Our results show that
the AFLP technique, which can simultaneously and assay a large number of loci randomly distributed in the genome, is much
more informative on the genetic relationship and origin of accessions than the limited number of morphological characters
conventionally used for variety discrimination. Up to about 9% molecular genetic differentiation was detected among morphologically
indistinguishable provenances of the same variety; this can be partly attributed to scoring error but mainly to somatic variation
occurring during vegetative propagation. On the other hand lower genetic distance values were sometimes found among varieties
which differ in morphological characters and are thus commercialised with different names. The possibility of considering
the amount of genetic variation within a variety as the threshold value for discrimination of initial varieties and essentially
derived varieties is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
538.
Marco A. Lazo-Vélez Víctor A. Gutiérrez-DíazAlicia Ramírez-Medrano Sergio O. Serna-Saldívar 《Journal of Cereal Science》2013
The effect of sodium selenite addition and fermentation times on production of selenomethionine (SeM) during sponge bread production was evaluated. Doughs were supplemented with sodium selenite (Na2SeO3) and fermented with yeast, avoiding addition of sulfur salts. The effect of Na2SeO3 on yeast activity was evaluated using a pressurometer. Results showed that there were not statistical differences (p < 0.05) in CO2 production and dough pH at all the sodium selenite concentrations tested. HPLC-fluorescence data showed that SeM production was higher with the increase of fermentation times, while less significant effects were observed due to changes in Na2SeO3 concentration. Two slices of Se-enriched bread can provide about 200 μg SeM, the dose recommended to prevent cancer and oxidative stress. The physical features (water absorption, bread weight, bread volume, color, density, oven spring, etc.) and organoleptic evaluations for the enriched loaves were evaluated. In all these parameters, the experimental enriched breads had practically identical attributes compared to the control. The breads rich in SeM have potential to be used as functional foods because this amino acid is synthesized into higher quantities of glutathione peroxidase, an enzyme considered as one of the most protective mechanisms against oxidative stress and preventive of cancer and chronic diseases. 相似文献
539.
Lenir Fátima Gotz Nerilde Favaretto Gabriel Barth Paulo Sergio Pavinato Volnei Pauletti 《Soil Use and Management》2023,39(1):606-617
The benefits of manure as a source of nutrients for plants and to improve soil quality are well-known. Monitoring of manure application is needed if environmental issues are to be prevented. In particular, the availability and accumulation of phosphorus (P) has to be subject to rigorous monitoring. This study aims to both evaluate the efficacy of the resin method in extracting inorganic labile P in soils under the long-term application of dairy liquid manure (DLM), and verify the influence of DLM on the recovery of applied P and soil legacy P. To realize our objectives, two long-term field experiments were established under a no-tillage system with annual DLM application on sandy clay loam (sandy Oxisol) and clayey (clayey Oxisol) soils. Treatment consisted of DLM applications (0, 60, 120, 180 m3 ha−1 year−1), independent of mineral fertilizer. Soil samples were taken from the 0–5, 5–10 and 10–15 cm layers after 10 years from the beginning of the trial. A single extraction with resin underestimated inorganic labile P; however, successive extractions were able to take up 43% and 26% of the total P in sandy and clayey Oxisols, respectively, whereas in a single extraction the take-up was 17% and 8% from the same soils, respectively. The resin method was more effective in extracting P from the sandy Oxisol. Thus, when interpreting soil P contents for fertilizer planning, the soil texture should be taken into account. DLM application decreased P recovered from applied P, ranging from 54% to 83% (sandy), and 43% to 67% (clayey), and substantially increased soil legacy P. 相似文献