scholarly journals Seasonal Pattern of Tomato Mosaic Tobamovirus Infection and Concentration in Red Spruce Seedlings

1998 ◽  
Vol 64 (4) ◽  
pp. 1436-1441 ◽  
Author(s):  
George D. Bachand ◽  
John D. Castello
Keyword(s):  
Seasonal Pattern ◽  
Early Spring ◽  
Red Spruce ◽  
Optimal Time ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Concentration ◽  
Control Root ◽  
Seedling Roots ◽  
One Year ◽  
Infected Seedling

ABSTRACT Tomato mosaic tobamovirus (ToMV) infects red spruce (Picea rubens) and causes significant changes in its growth and physiology. The mechanism of infection and the pattern of virus concentration in seedling roots and needles were investigated. One-year-old red spruce seedlings were obtained from the nursery in April and June 1995 and August 1996 and tested for ToMV using enzyme-linked immunosorbent assay (ELISA). Virus-free seedlings were divided into three treatments: control, root inoculated, and needle inoculated. Two control, five root-inoculated, and five needle-inoculated seedlings were sampled destructively at biweekly intervals for 3 months and then tested for ToMV by ELISA. ToMV was transmitted to seedlings by root but not by needle inoculation. The virus was detected in 67 to 100% of roots but in less than 7% of needles of root-inoculated seedlings. The percent infection of root-inoculated seedlings differed significantly between the April and June and between the April and August inoculation periods. Virus concentration in infected seedling roots increased initially, peaked within 4 weeks postinoculation, and steadily declined thereafter. Significant differences in ToMV concentrations in roots also were detected among inoculation periods and sampling dates. Early spring may represent the optimal time for infection of seedlings, as well as for assaying roots for ToMV.

Tomato mosaic virus infection of red spruce on Whiteface Mountain, New York: prevalence and potential impact

1995 ◽  
Vol 25 (8) ◽  
pp. 1340-1345 ◽  
Author(s):  
John D. Castello ◽  
George D. Bachand ◽  
Philip M. Wargo ◽  
Volker Jacobi ◽  
Donald R. Tobi ◽  
...  
Keyword(s):  
New York ◽  
Red Spruce ◽  
Tomato Mosaic Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Concentration ◽  
First Order ◽  
Virus Incidence ◽  
Potential Impact ◽  
Whiteface Mountain ◽  
Crown Dieback

Tomato mosaic tobamovirus (ToMV) was detected by enzyme-linked immunosorbent assay in the roots of red spruce (Picearubens Sarg.) on Whiteface Mountain, New York. Both virus incidence and concentration in the roots of red spruce vary by site and were greater in trees with little to moderate crown dieback than in trees with severe dieback. There was no significant association between virus incidence or concentration in the roots of red spruce and elevation on Whiteface Mountain. Multiple regression analysis of virus concentration in the roots, as the dependent variable, was performed against nine selected crown and root variables. In the final regression model, the number of live second-order nonwoody roots per length of first-order nonwoody root and length of the live crown were positively and negatively correlated, respectively, with virus concentration in the roots. These results suggest a complex epidemiology and a potentially significant impact of ToMV infection on the growth of red spruce on Whiteface Mountain.

Detection of Hepatitis a Virus in Drinking Water by Enzyme -Immunoassay Using Ultracentrifugation for Virus Concentration

1985 ◽  
Vol 17 (10) ◽  
pp. 39-41 ◽  
Author(s):  
A. Schnattinger
Keyword(s):  
Membrane Filtration ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Phosphate Buffer Solution ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Concentration ◽  
Buffer Solution ◽  
Solution Ph ◽  
Two Stage

Ten litres of tapwater were seeded with 200 µl (8×108 HAV particles) of a commercial (Organon Teknika) suspension of hepatitis A virus. Following WALTER and RÜDIGER (1981), the contaminated tapwater was treated with a two-stage technique for concentration of viruses from solutions with low virus titers. The two-stage technique consists of aluminium hydroxideflocculation (200 mg/l Al2(SO4)3. 18 H2O, pH 5,4-5,6) as first stage, the second stage of a lysis of aluminium hydroxidegel with citric acid/sodium citrate-buffer (pH 4,7; 1 ml/l sample), separation of viruses from the lysate by ultracentrifugation and suspension in 1 ml phosphate buffer solution (pH 7,2). A commercial solid phase enzyme-linked immunosorbent assay (ELISA) was used for the detection of HAV. HAV was detecterl in the 10.000:1 concentrates, but not in the seeded 101 samples. Approximately 4×108 of the inoculated 8×108 HAV particles were found in the 1 ml concentrates. The efficiency of detection is about 50%, the virus concentration 5000-fold. Although the percentage loss of HAV in comparison with concentration by means of membrane filtration is similar, the ultracentrifugation method yields a larger sample/concentrate ratio, so that smaller amounts of HAV can be detected more efficiently because of the smaller end-volume.

scholarly journals Reproductive phenology in a riparian rainforest in the south of Santa Catarina state, Brazil

2013 ◽  
Vol 85 (4) ◽  
pp. 1449-1460 ◽  
Author(s):  
MAINARA F. CASCAES ◽  
VANILDE CITADINI-ZANETTE ◽  
BIRGIT HARTER-MARQUES
Keyword(s):  
Plant Species ◽  
Resource Availability ◽  
Forest Ecosystems ◽  
Seasonal Pattern ◽  
Riparian Forests ◽  
Reproductive Phenology ◽  
Environmental Restoration ◽  
Fruit Availability ◽  
One Year ◽  
Riparian Plant

Phenological studies assist in forest ecosystems comprehension and evaluation of resource availability for wildlife, as well as in improving the understanding of relationships between plants and their pollinators and dispersers. This study aims to describe the reproductive phenophases of riparian plant species and correlate them with climatic variables. The reproductive phenology was analyzed biweekly throughout one year, recording the absence or presence of flowers/fruits. The flowering phenophase occurred throughout the year, with an increase in number of species in blossom in October, November, and December. The flowering peak of the community was observed in November. The fruiting phenophase also occurred throughout the year and showed an increase of species fruiting in June with a slight decrease in August and September. The data obtained in this study, when compared with other studies in different Atlantic Rainforest areas, indicates a seasonal pattern for the flowering phenophase and a variation in fruit availability throughout the year as well as in the fruiting peaks. Therefore, studies that observe flowering and fruiting events in loco are of main importance because they provide information on reproductive seasons of species for use in environmental restoration projects and thus alleviate the situation of degradation of riparian forests.

scholarly journals The effect of the queen's age on the Varroa mite (Varroa destructor) burden of honey bee (Apis mellifera L.) colonies

2018 ◽  
pp. 83-87
Author(s):  
Marianna Takács ◽  
János Oláh
Keyword(s):  
Apis Mellifera ◽  
Honey Bee ◽  
Varroa Destructor ◽  
Early Spring ◽  
Brood Chamber ◽  
One Year ◽  
The One ◽  
Post Hoc ◽  
Bee Colonies ◽  
Mite Mortality

An apiary trial was conducted in 2016 August to October in Szabolcs-Szatmár-Bereg County, Nyírmada to evaluate the influence of queen’s age on the Varroa destructor-burden in the treatment colonies. Sixty colonies of bees belonging to the subspecies Apis mellifera carnica pannonica in Hunor loading hives (with 10 frames in the brood chamber/deep super) were used. The colonies were treated with amitraz and the organophosphate pesticide coumaphos active ingredients. The amitraz treatment includes 6 weeks. The coumaphos treatment with Destructor 3.2% can be used for both diagnosis and treatment of Varroasis. For diagnosis, one treatment is sufficient. For control, two treatments at an interval of seven days are required. The colonies were grouped by the age of the queen: 20 colonies with one-year-old, 20 colonies with two-year-old and 20 colonies with three-year-old queen. The mite mortality of different groups was compared. The number of fallen mites was counted at the white bottom boards. The examination of spring growth of honey bee colonies has become necessary due to the judgement of efficiency of closing treatment. The data was recorded seven times between 16th March 2017 and 19th May 2017. Data on fallen mites were subjected to one-way analysis of variance (ANOVA) and Post-Hoc Tukey-test. Statistical analysis was performed using the software of IBM SPSS (version 21.). During the first two weeks after treatments, the number of fallen mites was significantly higher in the older queen’s colonies (Year 2014). The total mite mortality after amitraz treatment in the younger queen’s colonies was lower (P<0.05) compared to the three-year-old queen’s colonies. According to Takács and Oláh (2016) although the mitemortality tendency, after the coumaphos (closing) treatment in colonies which have Year 2014 queen showed the highest rate, considering the mite-burden the colonies belongs to the average infected category. The colonial maintenance ability of three-year-old queen cannot be judged based on the influencing effect on the mite-burden. The importance of the replacement of the queen was judged by the combined effect of several factors. During the spring-growth study (16th March–19th May) was experienced in the three-year-old queen’s colonies the number of brood frames significantly lower compared to the one- and two-year-old queen’s colonies. In the study of 17th April and 19th May each of the three queen-year-groups were varied. Therefore in the beekeeping season at different times were determined the colonial maintenance ability of queens by more factors: efficiency of closing treatment in early spring, the spring-growth of bee colonies, the time of population shift (in current study, this time was identical in each queen-year), honey production (from black locust).

scholarly journals Reef fish community structure on three islands of Itaipu, Southeast Brazil

2008 ◽  
Vol 6 (2) ◽  
pp. 267-274 ◽  
Author(s):  
José Policarpo de Mendonça-Neto ◽  
Cassiano Monteiro-Neto ◽  
Luiz Eduardo Moraes
Keyword(s):  
Environmental Gradients ◽  
Seasonal Pattern ◽  
Reef Fishes ◽  
Habitat Characteristics ◽  
Brazilian Coast ◽  
Rocky Reef ◽  
Fish Community Structure ◽  
Rocky Reefs ◽  
Chain Link ◽  
One Year

We provide here the first assessment of the composition, abundance and distribution of rocky reef fishes of Itaipu Sound, Rio de Janeiro, off the southeastern Brazilian coast. Monthly visual censuses, benthic quadrats and chain link transects were conducted over one year on rocky reefs at three islands (Menina, Mãe and Pai). A total of 2466 individual fish, belonging to 29 families and 42 species were recorded. The most abundant fish species were Parablennius pilicornis, Haemulon steindachneri, Orthopristis ruber and Diplodus argenteus. Sheltered and complex habitats showed the most abundant and diverse fish populations. There was a major significant separation between sampling sites and a secondary seasonal pattern. The three sites showed similar fish communities with locally structured environmental gradients according to their inherent habitat characteristics.

scholarly journals Sexual maturation in Atlantic salmon male parr may be triggered both in early spring and late summer under standard farming conditions

2021 ◽  
Author(s):  
Elia Ciani ◽  
Kristine von Krogh ◽  
Rasoul Nourizadeh-Lillabadi ◽  
Ian Mayer ◽  
Romain Fontaine ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Sexual Maturation ◽  
Late Summer ◽  
Early Spring ◽  
Plasma Testosterone ◽  
Farmed Salmon ◽  
Early Maturing ◽  
Advanced Stages ◽  
One Year ◽  
Immature Fish

AbstractMale Atlantic salmon (Salmo salar) display different sexual strategies, maturing either as parr during the freshwater phase (as sneaky spawners), or as post smolts following one or several years at sea. First sexual maturation (puberty) occurs at different times depending on environmental and genetic factors. To improve our knowledge on the timing (age and season) of first sexual maturation in Atlantic salmon male parr, we investigated pubertal activation in second generation farmed salmon from the Norwegian river Figgjo, reared under natural conditions of photoperiod and water temperature. Histological analysis, in combination with morphometric measurements, plasma androgen levels and pituitary gonadotropin gene expression analysis revealed that, as previously reported, some male parr initiated early sexual maturation in spring at one year of age. Interestingly, some male parr were observed to initiate sexual maturation already in autumn, six months after hatching (under-yearlings), much earlier than reported in previous studies. One-year old maturing males showed a low induction in gonadotropin levels, while under-yearling maturing males displayed a significant increase in fshb transcripts as compared to immature fish. Plasma testosterone, detectable also in immature males, increased constantly during testes development, while 11-ketotestosterone, undetectable in immature and early maturing males, increased during more advanced stages of maturation. A mild feminization of the testes (ovotestes) was detected in a subset of samples. This study brings new knowledge on the little investigated field of sexually maturing under-yearlings in Atlantic salmon. This is also the first study comparing the physiology of under-yearling vs one-year old maturing male parr, thus bringing new insights to the remarkable plasticity of Atlantic salmon puberty.

scholarly journals Evaluation of optimal time and parameters for measuring potentially mineralized nitrogen in soil

2008 ◽  
pp. 41-49
Author(s):  
Mirjana Kresovic ◽  
Vlado Licina ◽  
Svetlana Antic-Mladenovic
Keyword(s):  
Early Spring ◽  
Optimal Time ◽  
Soil Parameters ◽  
Anaerobic Incubation ◽  
Aerobic Incubation ◽  
Brown Forest Soil ◽  
Controlled Conditions ◽  
Long Term Experiments ◽  
Aerobic And Anaerobic

Our research was done on brown forest soil with long-term experiments and with a system of fertilizing which is in use for 40 years. Experiment variants with an increasing dose of nitrogen fertilizer were chosen for this research. Two experiments have been performed: experiment in pots supplied with ammonium nitrate labeled with a stable isotope 15N (11.8%) and experiment in the field. The aim of the research was to establish which plant and soil parameters group (obtained in the controlled conditions and/or in the field) could be considered as reliable for evaluation of aerobic and anaerobic incubation and of the best time for estimation of potentially mineralized nitrogen in soil. According to the determined correlative dependence, it could be concluded that reliability of aerobic incubation should be estimated in October by plant and soil parameters from field, anaerobic incubation should be estimated in early spring (March) by plant and soil parameters, from controlled conditions (pots) and from field.

scholarly journals Evidence of Neospora caninum exposure among native Korean goats (Capra hircus coreanae)

2014 ◽  
Vol 59 (No. 12) ◽  
pp. 637-640 ◽  
Author(s):  
BY Jung ◽  
SH Lee ◽  
D. Kwak
Keyword(s):  
Neospora Caninum ◽  
Control Strategies ◽  
Integrated Control ◽  
Protozoan Parasite ◽  
Capra Hircus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Caninum Infection ◽  
One Year ◽  
And Control

Neospora caninum is a protozoan parasite that causes abortion in ruminants, including goats. The objective of the present study was to determine the seroprevalence of N. caninum in native Korean goats (Capra hircus coreanae). A commercial enzyme-linked immunosorbent assay kit was used to analyse 464 serum samples for the presence of N. caninum antibodies. Four samples (0.9%, 95% confidence intervals &ndash; CI: 0.0&ndash;1.7) were found to be positive for N. caninum antibodies. The seroprevalence was analysed according to age (less than to one year, young; more than or equal one year, adult; and unknown), sampling season (April to September, warm; October to March, cold), and region (northern, central, and southern). However, there were no statistically significant differences in seroprevalence according to age, season, and region (P &gt; 0.05). This is the first report on the seroprevalence of N. caninum in native Korean goats. The results of this study indicate a nationwide distribution of N. caninum among goats, with a relatively low prevalence. Therefore, the implementation of integrated control strategies as well as measures for prevention and control of N. caninum infection among goats is recommended.

scholarly journals Guest or pest? Spatio-temporal occurrence and effects on soil and vegetation of the wild boar on Elba island

2020 ◽  
Author(s):  
Ilaria Greco ◽  
Ettore Fedele ◽  
Marco Salvatori ◽  
Margherita Giampaoli Rustichelli ◽  
Flavia Mercuri ◽  
...  
Keyword(s):  
Natural Habitat ◽  
Early Spring ◽  
Wild Boars ◽  
Occupancy Probability ◽  
Lower Elevation ◽  
Site Use ◽  
Temporal Occurrence ◽  
Elba Island ◽  
Spatio Temporal ◽  
One Year

AbstractWhere allochthonous large mammals, such as the wild boars, occur in high density, human-wildlife conflicts may arise. Thus, assessing their spatio-temporal patterns is paramount to their management. We studied the wild boars on Elba island, Italy, where they have been introduced and are perceived as pests to address their occurrence and impact of foraging on natural habitat. We surveyed the western island with three camera trapping surveys within one year. We found that the species' estimated occupancy probability was higher in summer-autumn (0.75 ± 0.14) and winter-early spring (0.70 ± 0.10) than in spring–summer (0.53 ± 0.15), whereas detection probability did not vary. Occupancy was significantly associated with lower elevation and woodland cover. Lower site use of wild boars during spring–summer might reflect lower food availability in this season and/or boars’ movements towards landfarms outside the sampled area. Detectability increased with proximity to roads during spring–summer and decreased with humans’ relative abundance in other periods. Boars were mainly nocturnal, with decreasing overlap with human activity when human presence was higher in the park. Soil degradation caused by wild boars was higher in pine plantations, which is the cover with a lower conservation interest. The spatio-temporal activity of wild boars on the island appears driven by seasonal preferences for food-rich cover and avoidance of human disturbance. The lowered site use in months with lower resources could partially reflect increased proximity to settled and farmed areas, which may trigger crop-raiding and the negative perception by residents.

Competition for nodule occupancy of introduced Bradyrhizobium japonicum strains in a Wisconsin soil with a low indigenous bradyrhizobia population

1990 ◽  
Vol 36 (12) ◽  
pp. 839-845 ◽  
Author(s):  
T. J. McLoughlin ◽  
S. Hearn ◽  
S. G. Alt
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Growing Season ◽  
Field Trials ◽  
Enzyme Linked Immunosorbent Assay ◽  
Nodule Occupancy ◽  
Antibiotic Resistant ◽  
Growing Seasons ◽  
Low Incidence ◽  
One Year ◽  
Successful Inoculation

The population dynamics of six introduced Bradyrhizobium japonicum strains were measured over three growing seasons in a Wisconsin soil with a low incidence of indigenous B. japonicum (10 cells/gm). Four antibiotic-resistant members of the 123 serocluster (which were either spectinomycin resistant or streptomycin resistant), USDA 110, and USDA 138 were inoculated using liquid inoculum, at a rate of 1 × 108 cells per 2.5-cm row, on two soybean cultivars in 1985. Nodule occupants were identified using an enzyme-linked immunosorbent assay (ELISA), fluorescent antibodies, and antibiotic-resistant mutants. In the first growing season, 100% of the nodules were formed by the introduced strains. The nodules from the uninoculated plots were occupied by an indigenous 110 serogroup. In the second and the third season at the same site (without further inoculation), a high percentage (> 60%) of the nodules from all the plots were nodulated by the 123 serocluster (either alone or as mixed infections). However, < 25% of the nodules in the 123-inoculated plots and < 9% in the other plots were formed by any of the antibiotic-marked 123 inoculum strains introduced in 1985. The main conclusions are (i) that it is possible to successfully introduce inoculum strains in soils where the indigenous Bradyrhizobium population is low and to obtain 100% nodule occupancy in the first growing season, and (ii) that successful inoculation in one year in soils with a low incidence of Bradyrhizobium does not ensure that the introduced inoculum strains will form nodules in subsequent years. Key words: Bradyrhizobium japonicum, indigenous bradyrhizobia, interstrain competition, field trials.

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