QTL for IHNV resistance and growth identified in a rainbow (Oncorhynchus mykiss) × Yellowstone cutthroat (Oncorhynchus clarki bouvieri) trout cross

Infectious hematopoietic necrosis virus (IHNV) is a major constraint to rainbow trout culture. Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) have greater resistance to this virus than do rainbow trout (O. mykiss), but the genetic mechanism of this resistance is not understood. We conducted a genome scan using a backcross of cutthroat trout into a rainbow trout background to estimate the number and locations of quantitative trait loci (QTL) associated with IHNV resistance and growth in trout. IHNV resistance was considered in terms of both survival (binary trait) and days to death (quantitative trait). The genetic map was scanned using interval mapping via two different approaches: one model considered survival alone and a second two-part model combined both survival and days to death. Three QTL were significantly (P ≤ 0.05) associated with virus resistance genome-wide, explaining 32.5% of the phenotypic variation. Cutthroat alleles at two of these QTL resulted in increased resistance to the pathogen, as expected. No growth QTL were detected in this cross. We suggest that these traits are genetically independent.     

Wheat grain quality under increasing atmospheric CO2 concentrations in a semi-arid cropping system

We investigated wheat (Triticum aestivum) grain quality under Free Air CO₂ Enrichment (FACE) of 550 ± 10% CO₂ μmol mol⁻¹. In each of two full growing seasons (2008 and 2009), two times of sowing were compared, with late sowing designed to mimic high temperature during grain filling. Grain samples were subjected to a range of physical, nutritional and rheological quality assessments. Elevated CO₂ increased thousand grain weight (8%) and grain diameter (5%). Flour protein concentration was reduced by 11% at e[CO₂], with the highest reduction being observed at the late time of sowing in 2009, (15%). Most of the grain mineral concentrations decreased under e[CO₂] - Ca (11%), Mg (7%), P (11%) and S (7%), Fe (10%), Zn (17%), Na (19%), while total uptake of these nutrients per unit ground area increased. Rheological properties of the flour were altered by e[CO₂] and bread volume reduced by 7%. Phytate concentration in grains tended to decrease (17%) at e[CO₂] while grain fructan concentration remained unchanged. The data suggest that rising atmospheric [CO₂] will reduce the nutritional and rheological quality of wheat grain, but at high temperature, e[CO₂] effects may be moderated. Reduced phytate concentrations at e[CO₂] may improve bioavailability of Fe and Zn in wheat grain.     

Grain Yield,Quality, and Nutrient Concentrations of Feed,Food, and Malt Barley

Barley (Hordeum vulgare L.) is a cereal grown for animal feed, human consumption, and malting. Nutrient concentrations are important as they provide information regarding the dietary values of barley consumed by animals or human beings. In addition, grain nutrient removal may be useful for refining fertilizer recommendations. A study was conducted in 2015 and 2016 investigating the cultivar effects on grain yield, quality, and grain nutrient concentrations and removal under irrigated conditions for two-row barley cultivars. Adjunct and feed cultivars produced the highest yields compared with the all-malt and food cultivars. Specific quality and nutrient values were greater than or equal to in the food cultivar compared to the malt or feed cultivars. Variations in nutrient concentrations were measured among the adjunct and all-malt cultivars, which could potentially affect the malting and brewing qualities. Grain yield, quality, nutrient concentrations and nutrient removal varied among cultivars grown under identical environmental conditions, which may influence end-use.     

Extraction of polyphenols from processed black currant (Ribes nigrum L.) residues

The total phenol and anthocyanin contents of black currant pomace and black currant press residue (BPR) extracts, extracted with formic acid in methanol or with methanol/water/acetic acid, were studied. Anthocyanins and other phenols were identified by means of reversed phase HPLC, and differences between the two plant materials were monitored. In all BPR extracts, phenol levels, determined by the Folin-Ciocalteu method, were 8-9 times higher than in the pomace extracts. Acid hydrolysis liberated a much higher concentration of phenols from the pomace than from the black currant press residue. HPLC analysis revealed that delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-glucoside, and cyanidin-3-O-rutinoside were the major anthocyanins and constituted the main phenol class ( approximately 90%) in both types of black currant tissues tested. However, anthocyanins were present in considerably lower amounts in the pomace than in the BPR. In accordance with the total phenol content, the antioxidant activity determined by scavenging of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation, the ABTS(*)(+) assay, showed that BPR extracts prepared by solvent extraction exhibited significantly higher (7-10 times) radical scavenging activity than the pomace extracts, and BPR anthocyanins contributed significantly (74 and 77%) to the observed high radical scavenging capacity of the corresponding extracts.     

Capillary electrophoresis and high-performance liquid chromatography determination of polyglutamyl 5-methyltetrahydrofolate forms in citrus products

The 5-methyltetrahydrofolate (5mTHF) polyglutamates in citrus products were analyzed by capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC). Folate species were purified from citrus products and concentrated from 2- to 100-fold using combined folate-affinity chromatography and C18 extraction. Seven polyglutamyl 5mTHFs were found in most not-from-concentrate (NFC) orange juices (OJ) in total amounts of approximately 1 nmol/mL, with varying distributions of individual polyglutamates. Folate amounts and distributions were also measured in orange fractions, single-strength OJ from concentrate, NFC grapefruit juice, and citrus peel molasses. Models containing ascorbic acid had folate thermal degradation rates one-seventh that of models without ascorbic acid. Pasteurization studies demonstrated that folate loss was <2% for commercial OJ pasteurization conditions (i.e., 93 degrees C for 5 s, 88 degrees C for 15 s, and 82 degrees C for 30 s). Both methods were precise, reproducible, and potentially faster than traditional analytical procedures requiring enzymatic deconjugation and microbial assays.     

Dynamic headspace analysis of the release of volatile organic compounds from ethanolic systems by direct APCI-MS

Static equilibrium headspace was diluted with a stream of nitrogen to study the stability of the volatile headspace concentration. The headspace dilution profile of 18 volatile compounds above aqueous and ethanolic solutions was measured in real time using atmospheric pressure chemical ionization-mass spectrometry. Under dynamic conditions the volatiles headspace concentration above water solutions decreased readily upon dilution. The presence of ethanol helped to maintain the volatile headspace concentration when the ethanol solution concentration was above 50 mL/L. This effect was such that under dynamic conditions the absolute volatile concentration above an ethanolic solution was higher than that above an aqueous solution, contrary to results observed in equilibrium studies. The ratio of the headspace concentration of volatiles above ethanolic 120 mL/L and water solutions was correlated to their air/water partition coefficient.     

Synthesis and phytotoxicity of new ionic liquids incorporating chiral cations and/or chiral anions

The aim of this work was to synthesize chiral ionic liquids as chiral solvents for organic synthesis and to evaluate the phyto(eco)toxicity of the new products and starting N-alkylimidazoles and their potential environmental influence on soil and plants. Chiral ionic liquids containing anions such as Cl-, Br-, TsO-, PF6(-), NO3(-), CF3SO3(-), and (+)- and (-)-C6H5CH(OH)C(O)O- were synthesized using (-)-(1R)-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-ethyl [(-)-(1R)-nopyl] halides (X = Cl, Br) and tosylate in 62-100% yields. The chloride 7 and the nitrate 13 ionic liquids possessed a toxicity dependent on the applied concentration. The lowest concentration causing a distinct reduction in plant germination/growth was 100 mg/kg. Spring barley better tolerated the ionic liquids (200 mg/kg) than common radish (100 mg/kg). The nitrate liquid did not exhibit an inhibiting effect on the germination ability of seeds. The starting N-methylimidazole used in lower concentrations (1 and 10 mg/kg of soil dry weight) was not phytotoxic, in contrast to higher doses (>1000 mg/kg).     

Management strategies to increase stand structural diversity and enhance biodiversity in coastal rainforests of Alaska

Coastal rainforests of southeast Alaska have relatively simple species composition but complex structures with high diversity of tree ages, sizes and forest canopy layers, and an abundant understory plant community. Wildlife and fisheries resources also play an important role in the ecological functioning of forest and aquatic systems. Clearcutting has greatly altered these forest ecosystems with significant decreases in structural diversity of forest stands and greatly reduced wildlife habitat. This paper synthesizes information on management options in older forests that have never been actively managed, and in younger forests to increase diversity of stand structures and their associated effects on biodiversity. Light to moderate levels of partial cutting in old-growth forests can maintain the original diversity of overstory stand structures and understory plant communities. In younger forests that develop after clearcutting, mixed alder-conifer stands provide more heterogeneous structures and significantly higher understory biomass than in pure conifer forests. Research has shown that red alder increases diversity and abundance of understory plants, and provides forage for deer and small mammals. Results also show a clear linkage between alder and improved invertebrate diversity in aquatic systems. A combination of light partial cutting in older forests along with inclusion of red alder in conifer-dominated forests could provide the greatest amount of diversity and maintain the complex stand structures that are an important component of these forest ecosystems.     

Rapid sedimentological and biological assessment of hydrocarbon contaminated sediments

It is possible to rapidly detect the presence of high concentrations of sediment associated hydrocarbons using a sediment profile camera and simultaneously evaluate the general sedimentological and biological character of a contaminated area. In sediments that were heavily contaminated with hydrocarbons from spills and chronic long-term additions the presence of hydrocarbons was seen about 50% of the time in the sediment profile images as unique features, ‘H spots’. The presence of these features was related to the concentration of hydrocarbons in the sediment. In highly contaminated muddy sediments ‘H spots’ were found in images collected at stations that had from 270 to 610 ppt total hydrocarbons. Sedimentological and biological information obtained from the sediment profile images confirmed the impacted nature of Elizabeth River sediments. Sediment profile imaging provide a means of obtaining an overall evaluation of the quality of a habitat and impacts on that habitat from pollution related environmental disturbances. While qualitative, an advantage of sediment profile image data is that they can be evaluated in less than a day and used to quickly locate inclusions of hydrocarbons in the sediments for further quantitative chemical or biological sampling, or mapping of heavily contaminated areas.     

Soil amidase activity in polyacrylamide-treated soils and potential activity toward common amide-containing pesticides

 Polyacrylamide (PAM) is currently used as an irrigation water additive to significantly reduce the amount of soil erosion that occurs during furrow irrigation of crops. Elevated soil amidase activity specific toward the large PAM polymer has been reported in PAM-treated field soils; the substrate specificity of the induced amidase is uncertain. PAM-treated and untreated soils were assayed for their capacity to hydrolyze the amide bond in carbaryl (Sevin), diphenamid (Dymid), and naphthalene acetamide. Based on results obtained with a soil amidase assay, there was no difference between PAM-treated and untreated soils with respect to the rate of amide bond hydrolysis of any of the agrochemicals tested. It appears that under these assay conditions the PAM-induced soil amidase is not active toward the amide bonds within these molecules. However, carbaryl was hydrolyzed by a different soil amidase. To our knowledge, this is the first soil enzyme assay-based demonstration of the hydrolysis of carbaryl by a soil amidase. Received: 23 June 1999