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1.
H. A. van der AA 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(3):109-115
A destructive leaf spot disease was found onNymphaea alba in the lakes near Kortenhoef, Netherlands. After comparison of fresh material and herbarium specimens the causal agent is namedColletotrichum nymphaeae (Pass.) van der Aa, comb. nov. Synonymy, morphology and cultural characters of the fungus are described and discussed. Some remarks on the relationship with several host plants are given and the provisional conclusion is that the species is a widespread parasite, but that the destructive attack in the Kortenhoef region is probably caused by a combination of various factors. 相似文献
2.
DW Bartlett JM Clough JR Godwin AA Hall M Hamer B Parr‐Dobrzanski 《Pest management science》2004,60(3):309-309
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry 相似文献
3.
Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season 下载免费PDF全文
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p < .05) and monocytes (2.93 ± 0.13; p < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer. 相似文献
4.
Marek Šmejkal Marie Prchalová Martin Čech Mojmír Vašek Milan Říha Tomáš Jůza Petr Blabolil Jan Kubečka 《Ecology of Freshwater Fish》2014,23(3):405-413
Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general. 相似文献
5.
Effect of dietary Schizochytrium microalga oil on selected markers of low‐grade inflammation in rats 下载免费PDF全文
T. Komprda Z. Sládek O. Škultéty S. Křížková V. Rozíková B. Němcová T. Šustrová M. Valová 《Journal of animal physiology and animal nutrition》2016,100(6):1169-1178
The objective of the present study was to evaluate a potential of Schizochytrium microalga oil to alleviate possible negative effects of high‐fat‐high‐energy diets. Forty adult male rats (Wistar Albino) were fed 7 weeks the diet containing beef tallow + evaporated sweetened milk (diet T) intended to cause mild obesity and low‐grade systemic inflammation. Consequently, the animals were divided into four groups by 10 animals each and fed either the T‐diet (control) or the diet containing 6% of safflower oil (S), 6% of fish oil (F) and 6% of Schizochytrium microalga oil (A), respectively, for another 7 weeks. The A‐diet decreased (p < 0.05) live weight to 86% and glycaemia to 85% of control, respectively; an effect of the S‐ and F‐diet on these markers was insignificant (p > 0.05). In comparison with control, higher (p < 0.05) deposition of eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) in the epididymal adipose tissue (EAT) of the A‐rats correlated with increased (p < 0.05) plasma adiponectin concentration, but it was without the effect (p > 0.05) on cellular adiponectin content in the EAT. Higher (p < 0.05) EPA+DHA deposition in the liver of the A‐rats correlated with higher expression (149% of control; p < 0.05) of the gene coding for peroxisome proliferator‐activated receptor gamma, and with lower expression (82% and 66%; p < 0.05) of the genes coding for adiponectin receptors AdipoR1 and AdipoR2; no relationship to the expression of receptor GPR120 was found. The A‐diet did not affect amount of the nuclear fraction of the nuclear factor kappa B in the liver, but increased plasma level of anti‐inflammatory cytokine TGF‐β1 (p < 0.05). The presented data agree with results of other in vivo rodent and human studies, but not with literature data regarding in vitro experiments: it can be concluded that the effects of dietary oils on inflammatory markers need further investigation. 相似文献
6.
A. Šimkūnas S. Valašinaitė V. Denisov A. Salytė 《Journal of Agronomy and Crop Science》2013,199(6):460-465
The study investigated the cultivars of non‐obligatorily requiring vernalization plant Festulolium braunii and assessed the influence of non‐hardy reproductive and hardy vegetative structures on overwintering effect. The study was conducted taking into account systemic relations between these types of structures. The results show the cultivars differ according to the percentage of headed and overwintered plants, when the cultivars with the most abundant heading – ‘Felopa’ and ‘Sulino’ – are also better at overwintering. The positive correlation between heading and overwintering characteristics was also observed, what seemed to be a rather new finding. It can be explained by systemic effect: non‐hardy later reproductive structures induce the post‐generative regrowth of vegetative shoots, which during shorter days halt development and become potentially hardy. More detailed interpretation is also provided including discussion of causal mechanisms of the detected phenomenon. The authors suppose that these mechanisms constitute a survival strategy for such perennial plants. The observed late heading which represents reproductive structures could be applied in plant breeding as a marker of winter‐hardiness among perennial grass plants which non‐obligatorily demand vernalization. 相似文献
7.
Michal Janáč Luděk Šlapanský Zdenka Valová Pavel Jurajda 《Ecology of Freshwater Fish》2013,22(3):430-438
Several Ponto‐Caspian gobiid species have recently expanded their ranges in Europe and North America. This is the first study to demonstrate passive downstream dispersal (drift) of the round goby (Neogobius melanostomus) and tubenose goby (Proterorhinus semilunaris) in newly colonised areas (River Dyje, Danube basin), a factor that could play an important role in their dispersal. Drift duration (i.e. number of dates on which the species was caught) in round goby was longer than that of both native species and tubenose goby, providing a possible advantage. Size of drifting fish was restricted to a narrow range of 6–8 mm and 5–8 mm for round and tubenose goby, respectively. Drift in both species occurred almost completely during hours of darkness (<1 lux) and fish size did not vary throughout the night. In both species, drift density increased significantly during the first hour after dusk. Round goby density gradually decreased up to dawn, while tubenose goby density varied throughout the night with no clear pattern. Drift of early life stages appears to be an important phenomenon that has not received adequate attention in studies of round and tubenose goby ecology and dispersal. 相似文献
8.
J. Fránová J. Přibylová M. Šimková M. Navrátil P. Válová 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(8):883-887
Strawflower (Helichrysum bracteatum) with symptoms resembling those associated to phytoplasma infection were observed in several areas in the Czech Republic during the period 1994–2001. Plants with leaf bronzing, reddening and necrosis, proliferation of secondary shoots, flower abnormalities and dwarfing died in advanced stages of the disease. The disease incidence ranged from 2% to 70% and caused significant loss to the flower and seed production. Transmission electron microscopy showed phytoplasmas in sieve cells of affected plants, but not in healthy ones. Association of phytoplasmas with the disease was confirmed by polymerase chain reaction using phytoplasma universal ribosomal primers R16F2n/R16R2. An amplification product of the expected size (1.2 kb) was observed in all samples of the symptomatic strawflowers. The restriction profiles obtained following separate digestion with three endonucleases (AluI, HhaI, MseI) showed that phytoplasmas infecting strawflowers from different localities in the Czech Republic were uniform and undistinguishable from aster yellows (subgroup 16SrI-B). Sequence analysis of 1771 bp of the ribosomal operon amplified with primers P1/U3, R16F2n/R2 and 16R758/P7 indicated that the closest related phytoplasmas were those associated with 'Rehmannia glutinosa var. purpurea', both originating from Bohemia. This is the first report on the occurrence of a phytoplasma-associated disease of strawflower in the Czech Republic. 相似文献
9.
Stefancíková A Stĕpánová G Derdáková M Pet'ko B Kysel'ová J Cigánek J Strojný L Cisláková L Trávnicek M 《Veterinary research communications》2002,26(8):601-611
In the course of epizootological research on Lyme borreliosis in domestic and farm animals, the serological evidence for the occurrence of this zoonosis in cattle was screened. An ELISA showed that 25.2% of cattle from seven geographical areas in Slovakia were positive for anti-Borrelia IgG antibodies. In particular localities, the seroprevalence ranged from 0.6% to 34.3%. Of 33 cases with clinical signs, 20 ELISA-positive samples were also confirmed in Western blots. The most frequent clinical signs were lameness and swollen joints, but most of the cases were asymptomatic. The occurrence of Borrelia burgdorferi antibodies and suspected clinical signs in cattle of Slovak regions indicates that veterinarians should pay attention to this disease in their clinical practice and include it within the differential diagnosis. 相似文献
10.
Dana Vašková Karel Petrzik Josef Špak 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(6):573-580
Sequences of the capsid protein gene and the preceding intergenic region of eleven isolates of prune dwarf virus from central Europe were determined. The isolates were obtained from plum, cherry and peach trees. Comparison of all sequenced isolates (including two sequences published previously) revealed high (88%) conservation of the capsid protein gene. The highest degree of identity was observed in the C-terminal half, where only 13 amino acid substitutions could be observed in contrast to the N-terminal half with 22 substitutions. No reasonable correlation between amino acid substitutions and host species and/or geographic origin of the isolates was observed. Alignment with capsid protein genes of other ilarviruses revealed apple mosaic virus, elm mottle virus, lilac ring mottle virus and prunus necrotic ringspot virus as the most related to prune dwarf virus. Unlike the isolates of related prunus necrotic ringspot virus all the isolates of prune dwarf virus shared extensive conservation of the intergenic region. Portions of RNA3 were selected for design of universal primers for PCR detection. 相似文献