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71.
72.
T. SVÅSAND O. T. SKILBREI G. I. VAN DER MEEREN M. HOLM 《Fisheries Management and Ecology》1998,5(6):473-490
Abstract The main question which must be raised when planning to enhance natural populations through sea ranching is whether reared organisms are fit for a life in the wild, or more specifically, whether there are differences between reared and naturally resident individuals. The causes and effects of these differences are reviewed, and results from the Norwegian enhancement programme, which compared reared and wild individuals of Atlantic salmon, Salmo salar L., Atlantic cod, Gadus morhua L., and European lobster, Homarus gammarus L., are discussed with emphasis on morphological and behavioural differences. It was concluded that exposure to an artificial rearing environment during ontogeny can affect both the phenotype and the behaviour of the reared individuals, and thereby, their potential for survival after release into the wild as well. Suggestions are made as to how to diminish observed differences, and thereby, improve the survival potential. 相似文献
73.
E. Navrozidis T. Thomidis T. Sipouridis I. Xatzicharisis I. Fotiadis D. Servis 《Phytoparasitica》2005,33(2):149-153
The effectiveness of the pheromone-based communication disruption method was examined against the summerfruit tortrix,Adoxophyes orana F.v.R. (Lepidoptera: Tortricidae), a pest of peach trees, using the new RAK 3+4 dispenser (BASF). NoA. orana males were captured in pheromone traps inside the experimental orchards, which were saturated with the RAK 3+4 dispensers.
The percent of damaged leaves was practically zero, while the level of damaged fruits was 0–6% in pheromone-treated orchards.
The percentage of fruit rot caused byMonilinia laxa was lower in pheromone-based communication disruption orchards than in the control. It was concluded that the RAK 3+4 dispenser
could be used againstA. orana as an economical and environmentally friendly method. 相似文献
74.
Sera collected from 447 dairy cattle on 14 dairy farms were tested for Neospora caninum antibodies by use of an immunofluorescent antibody technique. Positive reactions with titres > or =1:200 were found in 63 (14.09%) of animals. Neospora positive sera were also tested for Toxoplasma gondii antibodies by using a commercial latex agglutination test. Antibodies to T. gondii were detected in 3 (4.76%) of 63 N. caninum positive sera. These results indicate that N. caninum infection is widespread among dairy cattle in Bahia state. 相似文献
75.
I. Tóbiás D. Z. Maat H. Huttinga 《European journal of plant pathology / European Foundation for Plant Pathology》1982,88(5):171-183
Two Hungarian virus isolates from sweet pepper (K8) and melon (S4) were identified as cucumber mosaic virus (CMV) on the basis of host plant reactions and serology. The isolates were purified and antisera prepared. Homologous antiserum titers in double-diffusion tests were 256 (K8) and 512 (S4). They were serologically closely related to each other and to other CMV isolates. On the basis of symptoms they belong to different symptomatological groups of CMV; this was supported by serological properties. Sedimentation coefficients were c. 93 S, at 2 mg ml–1. Purified preparations, stained with 2% uranyl acetate, showed spherical particles. In ELISA purified preparations reacted with each other's antisera.Samenvatting Twee hongaarse virusisolaten uit paprika (K8) en meloen (S4) werden geïdentificeerd als komkommermozaïekvirus (CMV) met behulp van toetsplanten en serologie. Beide isolaten werden gezuiverd en er werden antisera tegen bereid. De homologe titers van de antisera in de agar-geldiffusietoets bedroegen 256 (K8) en 512 (S4). K8 en S4 waren serologisch nauw verwant aan elkaar, evenals aan andere CMV-isolaten. Op grond van hun symptomen op toetsplanten behoren ze tot verschillende symptomatologische groepen van CMV. Dit laatste werd gesteund door de serologische eigenschappen. Beide isolaten hebben een sedimentatiecoëfficiënt van ca 93 S, bij een concentratie van 2 mg ml–1. Gezuiverde preparaten, gekleurd met 2% uranylacetaat, bleken bolvormige deeltjes te bevatten. In ELISA reageerden gezuiverde preparaten van K8 en S4 met elkaars antisera. 相似文献
76.
M. von Lützow L. Zelles I. Scheunert J. C. G. Ottow 《Biology and Fertility of Soils》1992,13(3):130-134
Summary Seasonal effects of liming, irrigation, and acid precipitation on microbial biomass N and some physicochemical properties of different topsoil horizons in a spruce forest (Picea abies L.) were measured throughout one growing season. The highest biomass N was recorded in autumn and spring in the upper soil horizons, while the lowest values were obtained in summer and in deeper horizons. The clearest differences between the different soil treatments were apparent in autumn and in the upper horizons. Liming increased the microbial biomass N from 1.7% of the total N content to 6.8% (Olf1 layer) and from 1% to 2% of the total N content in the Of2 layer. The main inorganic-N fraction in the deeper horizons was NO
inf3
sup-
. An increase in cation exchange capacity was observed down to the Oh layer, while soil pH was only slightly higher in the Olf1 and Of2 layers after liming. The effects of irrigation were less marked. The microbial biomass N increased from 1.7% of total N to 4.8% in the Olf1 layer and from 1% to 2% of total N in the Of2 layer. In the Olf1 layer an increase in C mineralization was observed. Acid precipitation decreased the microbial biomass N in the upper horizons from 4.8% of total N to 1.8% in the Olf1 layer and from 2% to 0.5% in the Of2 layer. No significant changes in soil pH were observed, but the decrease in cation exchange capacity may result in a decrease in the proton buffering capacity in the near future. 相似文献
77.
78.
Paraud C Gaudin C Pors I Chartier C 《Veterinary journal (London, England : 1997)》2009,180(2):265-267
Paramphistome infections are very common in ruminants and may induce clinical signs, but little is known about effective treatments. In this study, the efficacy of oxyclozanide against Calicophoron daubneyi was studied in goats and its activity tested against immature stages (10 days post-infection) at a dose of 22.5mg/kg bodyweight (BW) and against adult stages using two doses (15 and 22.5mg/kg BW). There was a reduction (82%) in the number of immature worms (compared to controls) but the result was not statistically significant. When tested against adult stages, however, oxyclozanide reduced the worm burdens by 95.6% and 95.9% at doses of 15 and 22.5mg/kg BW, respectively, with no significant difference between the two doses. The experiment demonstrated that oxyclozanide is highly effective in reducing the number of adult paramphistomes in goats. 相似文献
79.
I. Halila M. J. Cobos J. Rubio T. Millán M. Kharrat M. Marrakchi J. Gil 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(1):87-92
A second gene conferring resistance to the chickpea wilt pathogen, Fusarium oxysporum f. sp ciceris race 0, has been mapped to linkage group 2 (LG2) of the chickpea genetic map. Resistance to race 0 is controlled by two genes
which segregate independently; one present in accession JG62 (Foc0
1
/foc0
1
) and mapping to LG5 and the second present in accession CA2139 (Foc0
2
/foc0
2
) but remaining unmapped. Both genes separately confer complete resistance to race 0 of the wilt pathogen. Using a Recombinant
Inbred Line (RIL) population that segregated for both genes (CA2139 × JG62) and the genotypic information provided by two
markers flanking Foc0
1
/foc0
1
ten resistant lines containing the resistant allele Foc0
2
/foc0
2
were selected. Genotypic analysis using these ten resistant lines paired with ten susceptible RILs, selected in the same
population, revealed that sequence tagged microsatellite sites (STMS) markers sited on LG2 were strongly associated with Foc0
2
/foc0
2
. Linkage analysis, using data from two mapping populations (CA2139/JG62 and CA2156/JG62), located Foc0
2
/foc0
2
in a region where genes for resistance to wilt races 1, 2, 3, 4 and 5 have previously been reported and which is highly saturated
with tightly-linked STMS markers that could be used in marker-assisted selection (MAS). 相似文献
80.