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101.
Helena L. G. de Bruyn 《European journal of plant pathology / European Foundation for Plant Pathology》1939,45(4):133-150
Samenvatting 1. Van verschillende chemische middelen bleek FeCl3 het eenige te zijn, dat in potproeven de schurft sterk deed verminderen.
2. De verschillende typen schurft bij dezelfde aardappelvari?teit worden door verschillendeActinomyces-stammen veroorzaakt.
3. EénActinomyces-stam kan op verschillende aardappelvari?teiten verschillende typen schurft verwekken; het type is specifiek voor iedere vari?teit.
4. EénzelfdeActinomyces-stam kan virulent zijn voor sommige aardappel-vari?teiten, terwijl hij andere vari?teiten in het geheel niet aantast; deze
laatste gedragen zich tegenover and ere stammen weer geheel anders.
5. In reincultuur ging de virulentie van vele stammen achteruit, van enkele bleef zij gelijk, bij één ging zij vooruit.
6. Door verblijkf op groeiende, levende aardappelknollen werd de verzwakte virulentie weer versterkt.
7. Het is wenschelijk, om in ons land de invloed van wisselbouw op het optreden van schurft na te gaan.
Investigations on certain Actinomycetes that cause Potato Scab相似文献
102.
103.
Tiago S. Nascimento Isabelle S. M. Silva Maria Cecília M. A. Alves Bruna B. Gouveia Lara Mariane R. Barbosa Taís J. S. Macedo Jamile M. S. Santos Alane P. O. Monte Maria Helena T. Matos Francine F. Padilha Isabel B. Lima‐Verde 《Reproduction in domestic animals》2019,54(1):31-38
This study aimed to characterize the hydroethanolic extract of red propolis (HERP) and nanoparticles containing HERP for using as an additive in the culture medium of isolated ovine preantral follicles. HERP was characterized by high‐performance liquid chromatography (HPLC) and determination of flavonoid content, and the nanoparticles by the mean particle diameter, polydispersity index (PI) and encapsulation efficiency (EE). The effect of HERP (10 and 20 ηg/ml—HERP10 and HERP20 groups) and nanoparticles (NP10 and NP20 groups) on isolated secondary follicles cultured in vitro for 12 days was observed by morphological evaluation, oxidative stress markers (reactive oxygen species—ROS and glutathione—GSH) and active mitochondria. HPLC showed formononetin as the major compound in the HERP (63.92 ± 0.21 μg/mL). The content of flavonoids ranged from 2.14% to 11.00%. The nanoparticles showed mean diameter of 287.5 ± 3.9 and 479 ± 18.1 ηm; PI of 0.117 ± 0.018 and 0.316 ± 0.039; and EE of 67.15% and 41%, respectively, for the NP10 and NP20 groups. After 12 days of culture, HERP20 and NP20 increased (p < 0.05) the percentage of normal follicles compared to NP10. HERP20 showed significantly higher percentages of antrum formation than control medium (MEM) and NP10 (p < 0.05). HERP20 also showed an increase (p < 0.05) in mitochondrial activity compared to the other treatments, except NP20 (p > 0.05), and increased GSH levels (p < 0.05) compared to MEM and HERP10. In conclusion, use of HERP (20 ηg/ml) on in vitro culture of isolated ovine preantral follicles can increase antrum formation, mitochondrial activity and GSH levels. 相似文献
104.
Effect of induced chronic atrial fibrillation on exercise performance in Standardbred trotters 下载免费PDF全文
Rikke Buhl Helena Carstensen Eva Zander Hesselkilde Bjørg Zinkernagel Klein Karen Margrethe Hougaard Kirsten Bomberg Ravn Ameli Victoria Loft‐Andersen Merle Friederike Fenner Christian Pipper Thomas Jespersen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(4):1410-1419
105.
Inês Rocha Ying Ma Miroslav Vostka Helena Freitas Rui S. Oliveira 《Journal of Agronomy and Crop Science》2019,205(5):447-459
Drought can drastically reduce cowpea [Vigna unguiculata (L.) Walp.] biomass and grain yield. The application of plant growth‐promoting rhizobacteria and arbuscular mycorrhizal fungi can confer resistance to plants and reduce the effects of environmental stresses, including drought. Seed coating is a technique which allows the application of minor amounts of microbial inocula. Main effects of the factors inoculation and water regime showed that: severe or moderate water deficit had a general negative impact on cowpea plants; total biomass production, seed weight and seed yield were enhanced in plants inoculated with P. putida; inoculation of R. irregularis significantly increased nitrogen (N) and phosphorus (P) shoot concentrations; and R. irregularis enhanced both chlorophyll b and carotenoids contents, particularly under severe water deficit. Plants inoculated with P. putida + R. irregularis had an increase in shoot P concentration of 85% and 57%, under moderate and severe water deficit, respectively. Singly inoculated P. putida improved potassium shoot concentration by 25% under moderate water deficit. Overall, in terms of agricultural productivity the inoculation of P. putida under water deficit might be promising. Seed coating has the potential to be used as a large‐scale delivery system of beneficial microbial inoculants. 相似文献
106.
Alphonsine Mukamuhirwa Helena Persson Hovmalm Rodomiro Ortiz Obedi Nyamangyoku Maria Luisa Prieto–Linde Anders Ekholm Eva Johansson 《Journal of Agronomy and Crop Science》2020,206(2):252-262
The climate change will contribute drought and temperature extremes to rice growing systems, especially when cultivated in equatorial regions. To evaluate opportunities to cultivate and breed drought-tolerant rice, seven rice cultivars were evaluated in Rwanda for recurring morphological drought scores, grain yield and components, and quality characteristics. The cultivation conditions, that is site and drought treatment, impacted morphological drought scores, growth and yield attributes, while cultivar affected quality attributes. Thus, site showed a higher impact on grain yield and components than drought and cultivar, with generally a reduced grain yield at the low-temperature site, as a result of low spikelet fertility. Morphological drought scores were generally increased by drought, while drought at the reproductive stage at the high-temperature site was negative for yield and its components. The cultivars “Intsindagirabigega” and “Jyambere” were adapted to high-temperature site conditions. The cultivar “Intsindagirabigega” had the highest amylose content, and “Mpembuke,” the highest antioxidant capacity. Thus, climate change with increased temperature and drought extremes may increase rice productivity in cool areas, while especially drought at reproductive stage will be detrimental in low altitude areas with high temperature. Cultivar variation indicated opportunities for selection and breeding of climate change tolerant rice cultivars which should be of immediate priority. 相似文献
107.
108.
Bruno Esteves António Velez Marques Idalina Domingos Helena Pereira 《Wood Science and Technology》2007,41(3):193-207
Heat treatment of Pinus pinaster and Eucalyptus globulus woods, two important species in Portugal, was performed in the absence of air by steaming, inside an autoclave, for 2–12 h
at 190–210°C. Mass losses increased with treatment time and temperature reaching 7.3% for pine and 14.5% for eucalypt wood.
The wood behaviour with moisture was improved. The equilibrium moisture content decreased by 46% for pine and 61% for eucalypt,
the dimensional stability increased (maximum anti-shrinking efficiency in the radial direction of 57 and 90% for pine and
eucalypt, respectively) and the surface wettability was lowered. In relation to mechanical properties, the modulus of elasticity
was little affected (maximum decrease of 5% for pine and 15% for eucalypt) but the bending strength was reduced (by 40% at
8% mass loss for pine and 50% at 9% mass loss for eucalypt wood). The variation of properties was related to treatment intensity
and mass loss but significant improvements could already be obtained for a 3–4% mass loss without impairing the mechanical
resistance. The response of eucalypt was higher than that of pinewood. Heat treatment of eucalypt wood shows an interesting
potential to improve the wood quality for solid timber products. 相似文献
109.
The variability of fibre and ray dimensions was studied at three radial positions (10, 50 and 90% of radius) in 5 cork oaks (Quercus suber L.) approximately 40 years old. Uniseriate ray height and cell number as well as multiseriate ray height and width were measured in tangential sections. Fibre length, width and wall thickness were measured after maceration. The most striking features of cork oak wood were the large multiseriate rays and the frequent homocellular uniseriate rays. On average multiseriate rays were 5.16 mm high and 0.48 mm wide, and uniseriate rays contained 11 cells and were 227 μm high. Neighbour rays presented large dimensional differences but there was no radial variation and there were very small between-tree differences. The radial maintenance of high and wide rays was discussed as a means to improve water shortage in response to water stress. Fibre dimensions increased radially but differed little between trees: on average, 960–1,220 μm length, 18.40–21.49 μm width and 6.66–8.07 μm wall thickness. The ray pattern showed enough variation for visual appreciation while ensuring within and between-tree uniformity. The presence of rays has to be taken into consideration for designing wood drying programs. 相似文献
110.
De Gobbi M Viprakasit V Hughes JR Fisher C Buckle VJ Ayyub H Gibbons RJ Vernimmen D Yoshinaga Y de Jong P Cheng JF Rubin EM Wood WG Bowden D Higgs DR 《Science (New York, N.Y.)》2006,312(5777):1215-1217
We describe a pathogenetic mechanism underlying a variant form of the inherited blood disorder alpha thalassemia. Association studies of affected individuals from Melanesia localized the disease trait to the telomeric region of human chromosome 16, which includes the alpha-globin gene cluster, but no molecular defects were detected by conventional approaches. After resequencing and using a combination of chromatin immunoprecipitation and expression analysis on a tiled oligonucleotide array, we identified a gain-of-function regulatory single-nucleotide polymorphism (rSNP) in a nongenic region between the alpha-globin genes and their upstream regulatory elements. The rSNP creates a new promoterlike element that interferes with normal activation of all downstream alpha-like globin genes. Thus, our work illustrates a strategy for distinguishing between neutral and functionally important rSNPs, and it also identifies a pathogenetic mechanism that could potentially underlie other genetic diseases. 相似文献