Resistance to Cephus cinctus Norton,the wheat stem sawfly,in a recombinant inbred line population of wheat derived from two resistance sources

Several species of wheat stem sawflies (WSS) are pests of wheat, including Cephus cinctus Norton in North America. Larvae feed inside the stems and cut the stem near plant maturity. The primary means of control is resistance due to solid stems, largely controlled by a locus on chromosome 3B (Qss.msub‐3BL). Cultivars that differed for WSS resistance, but with similar stem solidness, were crossed to determine the genetic basis for the differences. The cultivar ‘Scholar’ is susceptible, while ‘Conan’ shows resistance. Scholar and Conan possessed different alleles at Qss.msub‐3BL. Both alleles conferred solidness, yet the Conan allele conferred higher WSS resistance. An allele from Conan on chromosome 4A also decreased infestation and stem cutting. The 3B and 4A alleles from Conan acted in an additive fashion to provide increased WSS resistance without increasing stem solidness. Stem solidness has long been used by breeders as a proxy for WSS resistance because of its simplicity. Our results suggest that other resistance mechanisms may complement solid stems.     

Response of a rising 2-year-old natural Piedmont upland stand to fertilization

Hardwood stands in the southern U.S. are often regenerated naturally following clearcutting, with little or no silvicultural intervention in the early stages of stand development. Fertilizer was applied to a young naturally regenerating stand in order to evaluate the effectiveness of nutrient addition as a silvicultural tool in recently clearcut stands and to better understand the ecological relationships between site fertility and stand development. The study was installed on a rising 2-year-old naturally regenerated mixed pine-hardwood stand in the Hill Demonstration Forest in the Piedmont region (Durham County) of North Carolina. Fertilizer treatments were control, N, N + P, and N + P + K (at 200 kg N per ha, 50 kg P per ha and 100 kg K per ha). On a whole stand basis, increased growth rates were observed for trees on N + P and N + P + K plots. Fertilizer treatments did not affect total stand density, but the density of loblolly pine significantly decreased in N + P plots compared to the Control. The density of stems of stump origin also increased in plots receiving N + P. Density of sweetgum (Liquidambar styraciflua) significantly increased and hickory (Carya spp.) density decreased with the application of N + P. Dominant hardwood species with the exception of yellow-poplar (Liriodendron tulipifera) responded with an increase in height to only N + P fertilizer treatments. Yellow-poplar increased in groundline diameter, height and mean tree volume index with the application of N + P. Loblolly pine (Pinus taeda) responded to N + P + K fertilizer treatment with an increase in height, diameter and volume index over the Control. There was no growth response among treatments for the 16 largest trees per species per plot, with the exception of red oak (Quercus rubra) which responded with an increase in height in N + P plots. Projected growth responses were modeled on a whole stand level and indicate that the use of N + P fertilizer may be an effective silvicultural instrument to increase growth, accelerate stand development, and shorten rotation length.     

Metal contamination of bed sediments in the Irwell and Upper Mersey catchments,northwest England: exploring the legacy of industry and urban growth

Purpose

Manchester is often heralded as the first industrial city. Large volumes of physical and liquid contaminants were released into its river network throughout the industrial period up to the latter part of the twentieth century. Water quality has improved dramatically in recent decades, but, given their environmental significance, it is important to ascertain the extent to which a legacy of contamination persists in the modern bed sediments.

Materials and methods

Fine-grained bed sediments were sampled at 40 sites in the Mersey and Irwell catchments. Sediments were wet sieved to isolate the <63-μm grain size fraction. Metal concentrations were determined using XRF. Particle size characteristics were also measured. Sediments were subjected to a five-step sequential extraction procedure to ascertain the environmental significance of metal concentrations. Alongside archival research of past industry, enrichment factors, multivariate statistical techniques and conditional inferences trees were used to identify sources of heavy metals.

Results and discussion

Bed sediment-associated heavy metal(loid) concentrations were as follows: As (9.89–110 mg kg^?1), Cr (76.5–413 mg kg^?1), Cu (53.1–383 mg kg^?1), Pb (80.4–442 mg kg^?1) and Zn (282–1020 mg kg^?1). Enrichment factors ranged from moderate to extremely severe, with Pb showing the greatest enrichment across the catchments. Chemical mobility was generally low, but metal(loid) partitioning identified the influence of anthropogenic sources. Statistical analysis highlighted a number of point sources associated with former industrial sites that operated during the industrial period. Conditional inference trees highlighted the role of the textile industry on Cu concentrations in addition to indicating the complexity of sources, fluxes and stores of sediment-associated contamination throughout the system.

Conclusions

Fine-grained sediment-associated metal(loid)s in the Mersey and Irwell catchments are anthropogenically enriched. Concentrations also exceed sediment quality guidelines. A lack of distinct spatial patterning points to a complex network of contaminant inputs across the catchments, even in the headwaters. Whilst potential modern urban sources are likely to be important, spatial patterns and multivariate/data mining techniques also highlighted the importance of releases from former industrial sites as well as the reworking of historically contaminated floodplains and soils.

     

Environment influences food access and resulting shopping and dietary behaviors among homeless Minnesotans living in food deserts

Qualitative and quantitative methods were used to investigate how shopping behaviors and environment influence dietary intake and weight status among homeless Minnesotans living in food deserts. Seven focus groups (n = 53) and a quantitative survey (n = 255), using the social cognitive theory as the theoretical framework, were conducted at two homeless shelters (S1 and S2) in the Twin Cities area. Heights, weights, and 24-h dietary recalls were also collected. Food stores within a five-block radius of the shelters were evaluated for the price and availability of foods and compared to the Thrifty Food Plan’s market basket prices (MBP). Results showed that almost 80% of the sample was overweight or obese, with women consuming less than the recommended level for the fruits, vegetables, and milk food groups and excess for the fats/oils/sweets food group. Focus groups and participant surveys indicated that the shelter infrastructure and surrounding community influenced the types of foods available, food store access, and the foods purchased and consumed. Participants relied on food assistance programs, including food stamps, to supplement their food supply; however, some felt the high food prices at neighboring stores limited food choice and that food stamps did not adequately cover food costs. Results from the food store survey found the majority of food prices exceeded Midwest or national MBP. To promote healthier dietary intake and weight status, community-based interventions and city planners should aim to increase access to food through improved food availability and food access within the shelter environment and surrounding community.     

Characterization of Anopheles gambiae (African Malaria Mosquito) Ferritin and the Effect of Iron on Intracellular Localization in Mosquito Cells

Ferritin is a 24-subunit molecule, made up of heavy chain (HC) and light chain (LC) subunits, which stores and controls the release of dietary iron in mammals, plants, and insects. In mosquitoes, dietary iron taken in a bloodmeal is stored inside ferritin. Our previous work has demonstrated the transport of dietary iron to the ovaries via ferritin during oogenesis. We evaluated the localization of ferritin subunits inside CCL-125 [Aedes aegypti Linnaeus (Diptera: Culicidae), yellow fever mosquito] and 4a3b [Anopheles gambiae Giles (Diptera: Culicidae), African malaria mosquito] cells under various iron treatment conditions to further elucidate the regulation of iron metabolism in these important disease vectors and to observe the dynamics of the intracellular ferritin subunits following iron administration. Deconvolution microscopy captured 3D fluorescent images of iron-treated mosquito cells to visualize the ferritin HC and LC homologue subunits (HCH and LCH, respectively) in multiple focal planes. Fluorescent probes were used to illuminate cell organelles (i.e., Golgi apparatus, lysosomes, and nuclei) while secondary probes for specific ferritin subunits demonstrated abundance and co-localization within organelles. These images will help to develop a model for the biochemical regulation of ferritin under conditions of iron exposure, and to advance novel hypotheses for the crucial role of iron in mosquito vectors.     

High potential for selenium biofortification of lentils ( Lens culinaris L.)

Beneficial forms of selenium (Se) and their impact on human health are a global topic of interest in public health. We are studying the genetic potential for Se biofortification of pulse crops to improve human nutrition. Lentils ( Lens culinaris L.) are an important protein and carbohydrate food and are a valuable source of essential dietary components and trace elements. We analyzed the total Se concentration of 19 lentil genotypes grown at eight locations for two years in Saskatchewan, Canada. We observed significant genotypic and environmental variation in total Se concentration in lentils and that total Se concentration in lentils ranged between 425 and 673 microg kg(-1), providing 77-122% of the recommended daily intake in 100 g of dry lentils. Over 70% of the Se was present as selenomethionine (SeMet) with a smaller fraction (<20%) as inorganic Se and very small amounts as selenocysteine (SeCys). We found that soils from the locations where the lentils were grown were rich in Se (37-301 microg kg(-1)) and that lentils grown in Saskatchewan have the potential to provide an excellent natural source of this essential element. Our analyses gave us a preliminary understanding of the genetic basis of Se uptake in lentil and indicated that any potential strategy for micronutrient biofortification in lentil will require choice of field locations that minimize the spatial variability of soil Se content.     

Risk factors and implications associated with renal mineralization in chronic kidney disease in cats

BackgroundNephrocalcinosis is a pathological feature of chronic kidney disease (CKD). Its pathophysiological implications for cats with CKD are unexplored.ObjectivesIdentify nephrocalcinosis risk factors and evaluate its influence on CKD progression and all‐cause mortality.AnimalsFifty‐one euthyroid client‐owned cats with International Renal Interest Society (IRIS) stages 2‐3 azotemic CKD.MethodsRetrospective cohort study. Histopathological kidney sections were assessed for nephrocalcinosis (von Kossa stain). Nephrocalcinosis severity was determined by image analysis (ImageJ). Ordinal logistic regressions were performed to identify nephrocalcinosis risk factors. The influence of nephrocalcinosis on CKD progression and mortality risk were assessed using linear mixed model and Cox regression, respectively. Cats were categorized by their owner‐reported time‐averaged phosphate‐restricted diet (PRD) intake, where PRD comprised ≥50%, 10‐50%, or none of food intake.ResultsNephrocalcinosis was rated as mild‐to‐severe in 78.4% and absent‐to‐minimal in 21.6% of cases. Higher baseline plasma total calcium concentration (tCa; odds ratio [OR] = 3.07 per 1 mg/dL; P = .02) and eating a PRD (10%‐50%: OR = 8.35; P = .01; ≥50%: OR = 5.47; P = .01) were independent nephrocalcinosis risk factors. Cats with absent‐to‐minimal nephrocalcinosis had increasing plasma creatinine (0.250 ± 0.074 mg/dL/month; P = .002), urea (5.06 ± 1.82 mg/dL/month; P = .01), and phosphate (0.233 ± 0.115 mg/dL/month; P = .05) concentrations over a 1‐year period, and had shorter median survival times than cats with mild‐to‐severe nephrocalcinosis.Conclusion and Clinical ImportanceHigher plasma tCa at CKD diagnosis and PRD intake are independently associated with nephrocalcinosis. However, nephrocalcinosis is not associated with rapid CKD progression in cats.     

Three‐dimensional movements of harbour seals in a tidally energetic channel: Application of a novel sonar tracking system

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Occurrence of PPCPs at a Wastewater Treatment Plant and in Soil and Groundwater at a Land Application Site

Pharmaceuticals and personal care products (PPCPs) can reach soil and aquatic environments through land application of wastewater effluent and agricultural runoff. The objective of this research was to assess the fate of PPCPs at field scale. PPCPs were measured systematically in a wastewater treatment plant (WWTP), and in soil and groundwater receiving treated effluent from the WWTP. A land application site in West Texas was used as the study site; it has received treated wastewater effluent from the WWTP for more than 70 years in order to remove additional nutrients and irrigate non-edible crops. Target compounds (estrone, 17??-estradiol, estriol, 17??-ethynylestradiol, triclosan, caffeine, ibuprofen, and ciprofloxacin) in wastewater, sewage sludge, soil, and groundwater were determined using HPLC/UV with qualitative confirmatory analyses using GC/MS. Samples were collected quarterly over 12 months for wastewater and sludge samples and over 9 months for soil and groundwater samples. Results indicated that concentrations of PPCPs in wastewater influent, effluent, sludge solid phase, and sludge liquid phase were in the range of non-detected (ND)-183 ??g/L, ND-83 ??g/L, ND-19 ??g/g, and ND-50 ??g/L, respectively. Concentrations in soil and groundwater samples were in the range of ND-319 ng/g and ND-1,745 ??g/L, respectively. GC/MS confirmation data were consistent with the results of HPLC/UV analyses. Overall, data indicate that PPCPs in the wastewater effluent from the WWTP transport both vertically and horizontally in the soil, and eventually reach groundwater following land application of the effluent.