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961.
The purpose of this study was to determine the effect of AQUI‐S® (5.0 mg/L) sedation compared with nonsedation on the primary (plasma cortisol), secondary (osmoregulation), and tertiary (mortality) stress responses in Atlantic salmon smolts during transport and transfer to sea. AQUI‐S sedation during on‐ and off‐loading sufficiently reduced the primary stress response to lower mortality (2.5%) during transfer to sea compared with unsedated fish, which experienced a mortality rate above 11.5%. The unsedated fish experienced an acute mortality, which only stabilized 16 d after the transport. None of the secondary stress responses measured in this experiment could contribute in explaining this phenomenon, with the possible exception of plasma magnesium. While osmolality and chloride increased in both groups during the experiment, it did not seem to be related to the difference in the primary stress response documented in the sedated and unsedated groups. It instead appeared to be an effect of the salinity change from freshwater to seawater after transport. Plasma magnesium differed between the groups, while plasma magnesium in the AQUI‐S‐sedated group returned to prestress levels 12 h after transport. The unsedated group showed no such recovery even 1 wk after transport, which may indicate a disturbance in hydromineral balance and give plausible explanation for delayed mortality this group experienced. AQUI‐S shows promise as a stress‐reducing sedative for Atlantic salmon smolts and if used properly could improve animal welfare and survivability during and after common aquaculture‐related incidents. 相似文献
962.
Adil E Bala Albert Kollmann Paul-Henri Ducrot Amel Majira Lucien Kerhoas Robert Delorme Jacques Einhorn 《Pest management science》1999,55(2):206-208
Resveratrol and its oligomers: ε-viniferine, gnetin C, Pallidol and gnetin E, as well as three new dehydrodimers, cyphostemmines A–C, have been isolated from the roots of Cyphostemma crotalarioides (Ampelidaceae). Such compounds have not been reported previously in the family Ampelidaceae. Cis ε-viniferin has also been characterized as a minor component of the extract; it may have undergone partial transformation in solution into trans ε-viniferin. ©1999 Society of Chemical Industry 相似文献
963.
Mehraj Abbasov Zeynal Akparov Thomas Gross Sevda Babayeva Vusala Izzatullayeva Elchin Hajiyev Khanbala Rustamov Patrick Gross Mehmet Tekin Taner Akar Shiaoman Chao Robert Brueggeman 《Genetic Resources and Crop Evolution》2018,65(5):1441-1453
Genetic diversity of 139 accessions of diploid Triticum species including Triticum urartu, Triticum boeoticum and Triticum monococcum was studied using 11 SSR (simple sequence repeats) markers. A total of 111 alleles with an average of 10 alleles per locus were detected. The polymorphism information content (PIC) of each SSR marker ranged from 0.30 to 0.90 with an average value of 0.62. Among the three Triticum species T. urartu had the highest number of total alleles (Na?=?81), private alleles (Npa?=?15) and showed higher genetic diversity (Hex?=?0.58; PIC?=?0.54). The genotypes from Turkey exhibited the highest genetic diversity (PIC?=?0.6), while the least diversity was observed among 4 Georgian accessions (PIC?=?0.11). Cluster analysis was able to distinguish 139 wheat accessions at the species level. The highest genetic similarity (GS) was noted between T. boeticum and T. monococcum (GS?=?0.84), and the lowest between T. urartu and T. monococcum (GS?=?0.46). The grouping pattern of the PCoA analysis corresponded with cluster analysis. No significant differences were found in clustering of T. urartu and T. monococcum accessions with respect to their geographic regions, while within T. boeoticum species, accessions from Iran were somewhat associated with their geographical origin and clustered as a close and separate group. The results from our study demonstrated that SSR markers were good enough for further genetic diversity analysis in einkorn wheat species. 相似文献
964.
Eric M. Gerbrandt Robert H. Bors Ravindra N. Chibbar Thomas E. Baumann 《Genetic Resources and Crop Evolution》2018,65(5):1471-1484
Blue honeysuckle (Lonicera caerulea L.) is a northern-adapted crop species with extremely early phenology and cold hardiness. Restricted adaptation to temperate climates is a current limitation to the crop’s mainstream potential for large-scale production. Based on the broad germplasm base at the University of Saskatchewan, vegetative growth cessation and leaf drop phenology were characterized to complement analysis of spring phenological adaptation in a temperate climate. A multi-trial site of three foundation groups and a single-site trial of three improved groups compared with their parental foundation genotypes were conducted in the Fraser Valley, British Columbia, Canada in 2012 and 2013. The current study shows that blue honeysuckle germplasm contains considerable phenological variation that will permit adaptation to temperate climates. It also demonstrates that breeding for improved adaptation is possible using the existing germplasm resources. For Russian germplasm with the earliest phenology, adaptation to northern latitudes and short growing seasons results in early floral initiation, which presents an indirect limitation to production in more southern latitudes due to secondary flowering. Early leaf drop indirectly limits production and is related to poor adaptation to high chill environments. Skew toward later leaf drop in improved groups, produced from hybridization with Japanese and Kuril germplasm with intermediate and late phenologies, respectively, shows that development of better adaptation to southern latitudes can be achieved. 相似文献
965.
D. Michael Jackson Howard F. Harrison Robert L. Jarret Philip A. Wadl 《Genetic Resources and Crop Evolution》2018,65(4):1217-1236
The United States Department of Agriculture (USDA), Agricultural Research Service (ARS), Plant Genetic Resources Conservation Unit in Griffin, GA maintains the United States germplasm collection for Ipomoea spp. (Convolvulaceae). During 2012–2014, 737 sweetpotato, Ipomoea batatas (L.) Lam., plant introductions (PI) were acquired as tissue-culture plantlets and then acclimated to greenhouse conditions at the USDA, ARS, U. S. Vegetable Laboratory (USVL), Charleston, SC. Single plants were transferred to plastic-covered plant beds to produce cuttings for replicated field trials. Storage roots were harvested from 690 PIs grown in the field and 695 PIs grown in pots. Color coordinates were obtained for each PI using a tristimulus colorimeter. Hue angle values (h*) ranged from 8.2° to 88.3° (\( \bar{x} \) = 54.9°) for the periderm (peel or skin) of field-grown storage roots (n = 690 PIs) and ? 9.4° (= 350.6°) to 96.2° (\( \bar{x} \) = 51.3°) for pot-grown roots (n = 695 PIs). The red–green coordinate (a*) ranged from 0.8 to 30.7 (\( \bar{x} \) = 12.8) for the periderm of field-grown roots and ? 2.0 to 44.9 (\( \bar{x} \) = 16.1) for pot-grown roots. The yellow–blue coordinate (b*) ranged from 2.8 to 33.1 (\( \bar{x} \) = 19.4) for the periderm of field-grown roots and ? 7.4 to 38.1 (\( \bar{x} \) = 19.3) for pot-grown roots. Color saturation (chroma, C*) ranged from 13.7 to 35.8 (\( \bar{x} \) = 24.9) for the periderm of field-grown roots and 14.9–45.5 (\( \bar{x} \) = 29.3) for pot-grown roots. Lightness (white–black, L*) ranged from 32.6 to 81.7 (\( \bar{x} \) = 54.6) for the periderm of field-grown roots and 32.1–88.2 (\( \bar{x} \) = 64.0) for pot-grown roots. Hue angles ranged from ? 13.1° (= 346.9°) to 100.9° (\( \bar{x} \) = 80.9°) for the stele (flesh) of field-grown storage roots (n = 672 PIs) and ? 29.9° to 103.5° (\( \bar{x} \) = 81.6°) for pot-grown roots (n = 676 PIs); a* ranged from ? 5.6 to 35.0 (\( \bar{x} \) = 8.0) for the stele of field-grown roots and ? 6.0 to 41.0 (\( \bar{x} \) = 7.6) for pot-grown roots; and b* ranged from ? 7.7 to 56.1 (\( \bar{x} \) = 34.6) for the stele of field-grown roots and ? 12.6 to 56.1 (\( \bar{x} \) = 31.8) for pot-grown roots. C* ranged from 12.7 to 65.8 (\( \bar{x} \) = 37.2) for the stele of field-grown roots and 8.9–65.7 (\( \bar{x} \) = 34.5) for pot-grown roots; and L* ranged from 27.8 to 91.1 (\( \bar{x} \) = 77.7) for the stele of field-grown roots and 28.2–91.9 (\( \bar{x} \) = 80.4) for pot-grown roots. There were significant relationships between stele color (h*) and percent dry matter, with orange stele having a significantly lower % dry matter (\( \bar{x} \) = 25.6%, n = 183) compared with roots with cream/white stele (\( \bar{x} \) = 30.8%, n = 373). There appears to be wide genetic diversity for root color characteristics for the United States sweetpotato germplasm collection. 相似文献
966.
Voter‐Approved Annexations in an Urban Growth Boundary Regime: The Impacts on Housing Values,Density, and Economic Equity
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Rebecca Lewis Robert Parker Zhenpeng Zou Winston Hovekamp Megan Mcgowen Ryan Sherrard 《Growth and change》2018,49(2):286-313
Oregon is known for its strict Urban Growth Boundary (UGB) policies. While UGBs are designed to accommodate land supply for 20 years of growth, land within UGBs must be annexed into city limits before it can be developed at urban densities and serviced. In Oregon, cities use a variety of municipal annexation and voter‐approved annexation policies (VAAPs), providing an opportunity to study how different annexation policies affect land and housing markets, and affect urban density. Previous research on annexation has not considered how annexation policy influences housing values. This paper examines how VAAPs impact land growth, housing development, and density at the city level. It also examines how VAAPs impact housing values. Based on city‐level and tax‐lot‐level statistical analyses from 107 cities outside Portland Metro area, the results suggest that VAAPs negatively impact the availability of developable land within city limits. VAAPs also positively impact residential density and housing value. Lastly, VAAPs inequitably affect housing value between relatively high‐value housing and relatively low‐value housing, posing economic equity impacts for lower value housing. These findings provide important lessons for Oregon and other states. While VAAPs may increase residential density in cities, the policies may exacerbate affordability problems. 相似文献
967.
Relationships between individual movement,trophic position and growth of juvenile pike (Esox lucius)
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Marina J. Nyqvist Julien Cucherousset Rodolphe E. Gozlan J. Robert Britton 《Ecology of Freshwater Fish》2018,27(1):398-407
Variation in movement between individuals can have important ecological effects on populations and ecosystems, yet the factors driving differences in movement and their consequences remain poorly understood. Here, individual variability in the movements of juvenile (age 0 + and 1 + year) pike Esox lucius was assessed using passive integrated transponder (PIT) telemetry in off‐channel nursery areas over a 26‐ month period. Differences in the movement patterns of individuals were tested against their body sizes, ages, growth rates and trophic positions using data collected through a combination of catch‐and‐release sampling and stable isotope analyses. Results revealed that variation in movement between individuals was affected by age, with 1 + individuals moving more than individuals of age 0 + , but not length. Individuals whose TP was low on their initial capture event moved significantly less than those with a higher initial TP. Individuals that moved more grew faster and achieved a higher final TP. These results suggest that higher activity (i.e., increased movement) increases resource acquisition that enhances growth rates, which could ultimately maximise individual performances. 相似文献
968.
Early life history connectivity of Antarctic silverfish (Pleuragramma antarctica) in the Ross Sea
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Cassandra M. Brooks Jilda Alicia Caccavo Julian Ashford Robert Dunbar Kimberly Goetz Mario La Mesa Lorenzo Zane 《Fisheries Oceanography》2018,27(3):274-287
A recent population hypothesis for Antarctic silverfish (Pleuragramma antarctica), a critical forage species, argued that interactions between life history and circulation associated with glacial trough systems drive circumpolar distributions over the continental shelf. In the Ross Sea, aggregations of eggs and larvae occur under fast ice in Terra Nova Bay, and the hypothesis predicted that dispersing larvae encounter outflow along the western side of Drygalski Trough. The outflow advects larvae towards the shelf‐break, and mixing with trough inflow facilitates return toward the inner shelf. To examine the hypothesis, we compared samples of P. antarctica collected near Coulman Island in the outflow, along Crary Bank in the inflow, and a third set taken over the rest of the Ross Sea. We ruled out misidentification using an innovative genetic validation. Silverfish larvae comprised 99.5% of the catch, and the highest population densities were found in Drygalski Trough. The results provided no evidence to reject the population hypothesis. Abundance indices, back‐calculated hatching dates, length distributions and growth were congruent with a unified early life history in the western Ross Sea, constrained by cryopelagic early stages in Terra Nova Bay. By contrast, a sample in the Bay of Whales revealed much smaller larvae, suggesting either a geographically separate population in the eastern Ross Sea, or westward connectivity with larvae spawned nearby by fish sourced from troughs upstream in the Amundsen Sea. These results illustrate how hypotheses that integrate population structure with life history can provide precise spatial predictions for subsequent testing. 相似文献
969.
970.
Matthew D. Wilson Adelina Latinovic Noel W. Davies Peter B. McQuillan Robert C. Menary 《Journal of Crop Improvement》2018,32(3):331-352
Tasmanian Mountain Pepper is a new crop that produces a valuable flavoring agent derived from its fruit. However, annual yields are unpredictable and its commercial prospects depend upon a reliable fruit set. As poor pollination is a possible cause, the pollination biology of this dioecious plant was examined in natural and plantation settings using direct observations, sticky traps, gas chromatography, and microscopy. A community of small insects visits the flowers, and the insect species represent at least seven families of small flies, three families of beetles, and various wasps and moths. Pollen grains were observed on the bodies of bibionid flies (Bibionidae), syrphid flies (Syrphidae), and snail-flies (Sciomyzidae). The tetrahedral tetrad pollen grains are unlikely to be suitable for dispersal by wind. Similar volatiles were emitted by both males and females; several ocimene compounds are attractants for insect pollen vectors. The female flowers also emitted indole, a known fly attractant. It is therefore likely that Tasmannia lanceolata is dependent on the services of diverse insects, especially Diptera, for promoting fruit set. Plantations should be established in the vicinity of biodiverse native vegetation that supports a wide variety of native flying insects capable of transferring pollen. 相似文献