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1.
BMC Genomics ; 23(1): 390, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606708

RESUMO

BACKGROUND: Grain yield is a complex trait that results from interaction between underlying phenotypic traits and climatic, edaphic, and biotic variables. In rice, main culm panicle node number (MCPNN; the node number on which the panicle is borne) and maximum node production rate (MNPR; the number of leaves that emerge per degree-day > 10°C) are primary phenotypic plant traits that have significant positive direct effects on yield-related traits. Degree-days to heading (DDTH), which has a significant positive effect on grain yield, is influenced by the interaction between MCPNN and MNPR. The objective of this research is to assess the phenotypic variation of MCPNN, MNPR, and DDTH in a panel of diverse rice accessions, determine regions in the rice genome associated with these traits using genome-wide association studies (GWAS), and identify putative candidate genes that control these traits. RESULTS: Considerable variation was observed for the three traits in a 220-genotype diverse rice population. MCPNN ranged from 8.1 to 20.9 nodes in 2018 and from 9.9 to 21.0 nodes in 2019. MNPR ranged from 0.0097 to 0.0214 nodes/degree day > 10°C in 2018 and from 0.0108 to 0.0193 nodes/degree-day > 10°C in 2019. DDTH ranged from 713 to 2,345 degree-days > 10°C in 2018 and from 778 to 2,404 degree-days > 10°C in 2019. Thirteen significant (P < 2.91 x 10-7) trait-single nucleotide polymorphism (SNP) associations were identified using the multilocus mixed linear model for GWAS. Significant associations between MCPNN and three SNPs in chromosome 2 (S02_12032235, S02_11971745, and S02_12030176) were detected with both the 2018 and best linear unbiased prediction (BLUP) datasets. Nine SNPs in chromosome 6 (S06_1970442, S06_2310856, S06_2550351, S06_1968653, S06_2296852, S06_1968680, S06_1968681, S06_1970597, and S06_1970602) were significantly associated with MNPR in the 2019 dataset. One SNP in chromosome 11 (S11_29358169) was significantly associated with the DDTH in the BLUP dataset. CONCLUSIONS: This study identifies SNP markers that are putatively associated with MCPNN, MNPR, and DDTH. Some of these SNPs were located within or near gene models, which identify possible candidate genes involved in these traits. Validation of the putative candidate genes through expression and gene editing analyses are necessary to confirm their roles in regulating MCPNN, MNPR, and DDTH. Identifying the underlying genetic basis for primary phenotypic traits MCPNN and MNPR could lead to the development of fast and efficient approaches for their estimation, such as marker-assisted selection and gene editing, which is essential in increasing breeding efficiency and enhancing grain yield in rice. On the other hand, DDTH is a resultant variable that is highly affected by nitrogen and water management, plant density, and several other factors.


Assuntos
Estudo de Associação Genômica Ampla , Oryza , Variação Biológica da População , Grão Comestível/genética , Oryza/genética , Fenótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único
2.
Glob Chang Biol ; 28(8): 2689-2710, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35043531

RESUMO

Crop models are powerful tools to support breeding because of their capability to explore genotype × environment×management interactions that can help design promising plant types under climate change. However, relationships between plant traits and model parameters are often model specific and not necessarily direct, depending on how models formulate plant morphological and physiological features. This hinders model application in plant breeding. We developed a novel trait-based multi-model ensemble approach to improve the design of rice plant types for future climate projections. We conducted multi-model simulations targeting enhanced productivity, and aggregated results into model-ensemble sets of phenotypic traits as defined by breeders rather than by model parameters. This allowed to overcome the limitations due to ambiguities in trait-parameter mapping from single modelling approaches. Breeders' knowledge and perspective were integrated to provide clear mapping from designed plant types to breeding traits. Nine crop models from the AgMIP-Rice Project and sensitivity analysis techniques were used to explore trait responses under different climate and management scenarios at four sites. The method demonstrated the potential of yield improvement that ranged from 15.8% to 41.5% compared to the current cultivars under mid-century climate projections. These results highlight the primary role of phenological traits to improve crop adaptation to climate change, as well as traits involved with canopy development and structure. The variability of plant types derived with different models supported model ensembles to handle related uncertainty. Nevertheless, the models agreed in capturing the effect of the heterogeneity in climate conditions across sites on key traits, highlighting the need for context-specific breeding programmes to improve crop adaptation to climate change. Although further improvement is needed for crop models to fully support breeding programmes, a trait-based ensemble approach represents a major step towards the integration of crop modelling and breeding to address climate change challenges and develop adaptation options.


Assuntos
Oryza , Adaptação Fisiológica , Mudança Climática , Oryza/genética , Fenótipo , Melhoramento Vegetal
3.
Plant Dis ; 105(10): 2981-2989, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33779262

RESUMO

Sheath blight (ShB; caused by Rhizoctonia solani AG1-1A) and narrow brown leaf spot (NBLS; Cercospora janseana) are among the most important diseases affecting rice production in Texas and other southern parts of the United States. Because of the high yield potential, hybrid rice acreage is continually increasing. Understanding the relative levels of resistance to ShB and NBLS in hybrids compared to those of inbreds is important for effective disease management; however, this information remains largely unknown. A comparison of the performance of hybrid rice and inbred rice was performed involving 173 hybrid and 155 inbred genotypes (cultivars and elite breeding lines) over the course of five crop seasons (2016 to 2020) and two locations in Texas. The results showed that genotype, cultivar type (hybrid or inbred), location, and their interactions had significant effects on the severity of ShB and NBLS. The ShB severity in hybrid genotypes was significantly lower than that in inbred genotypes, with an average reduction of 27% in disease severity during the 5-year, two-location evaluation. Most (53%) of the hybrid genotypes were rated moderately resistant, whereas almost all (97%) of the inbred genotypes ranged from very susceptible to moderately susceptible. Similarly, NBLS severity in hybrid genotypes is significantly lower than that in inbred genotypes. All but four hybrid genotypes exhibit immune reactions to NBLS. In contrast, 77% of inbred genotypes exhibit NBLS symptoms, with disease resistance reactions ranging from susceptible to resistant. The results demonstrate that hybrid rice is generally less susceptible to sheath blight and has a higher level of resistance against NBLS compared with inbred rice.


Assuntos
Oryza , Resistência à Doença/genética , Genótipo , Oryza/genética , Doenças das Plantas/genética , Texas , Estados Unidos
4.
Glob Chang Biol ; 23(11): 4651-4662, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28273392

RESUMO

Growing food crops to meet global demand and the search for more sustainable cropping systems are increasing the need for new cultivars in key production areas. This study presents the identification of rice traits putatively producing the largest yield benefits in five areas that markedly differ in terms of environmental conditions in the Philippines, India, China, Japan and Italy. The ecophysiological model WARM and sensitivity analysis techniques were used to evaluate phenotypic traits involved with light interception, photosynthetic efficiency, tolerance to abiotic stressors, resistance to fungal pathogens and grain quality. The analysis involved only model parameters that have a close relationship with phenotypic traits breeders are working on, to increase the in vivo feasibility of selected ideotypes. Current climate and future projections were considered, in the light of the resources required by breeding programs and of the role of weather variables in the identification of promising traits. Results suggest that breeding for traits involved with disease resistance, and tolerance to cold- and heat-induced spikelet sterility could provide benefits similar to those obtained from the improvement of traits involved with canopy structure and photosynthetic efficiency. In contrast, potential benefits deriving from improved grain quality traits are restricted by weather variability and markedly affected by G × E interactions. For this reason, district-specific ideotypes were identified using a new index accounting for both their productivity and feasibility.


Assuntos
Mudança Climática , Oryza , Cruzamento , China , Produtos Agrícolas , Grão Comestível , Temperatura Alta , Índia , Itália , Japão , Oryza/fisiologia , Fenótipo , Filipinas
5.
MMWR Morb Mortal Wkly Rep ; 66(43): 1182-1184, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29095808

RESUMO

Cyanobacteria, also known as blue-green algae, are photosynthetic, aquatic organisms found in fresh, brackish, and marine water around the world (1). Rapid proliferation and accumulation of potentially toxin-producing cyanobacteria characterize one type of harmful algal bloom (HAB). HABs have the potential to cause illness in humans and animals (2,3); however, the epidemiology of these illnesses has not been well characterized. Statewide in 2015, a total of 139 HABs were identified in New York, 97 (70%) of which were confirmed through laboratory analysis; 77 independent beach closures were ordered at 37 beaches on 20 different bodies of water. To better characterize HAB-associated illnesses, during June-September 2015, the New York State Department of Health (NYSDOH) implemented a pilot surveillance system in 16 New York counties. Activities included the collection of data from environmental HAB reports, illness reports, poison control centers, and syndromic surveillance, and increased outreach to the public, health care providers, and veterinarians. During June-September, 51 HAB-associated illnesses were reported, including 35 that met the CDC case definitions*; 32 of the cases occurred in humans and three in dogs. In previous years, New York never had more than 10 HAB-associated illnesses reported statewide. The pilot surveillance results from 16 counties during a 4-month period suggest that HAB-associated illnesses might be more common than previously reported.


Assuntos
Doença/etiologia , Doenças do Cão/etiologia , Proliferação Nociva de Algas , Vigilância da População , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Doenças do Cão/epidemiologia , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Projetos Piloto , Adulto Jovem
6.
Am J Public Health ; 106(3): 440-2, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26794161

RESUMO

We identified hospital visits with reported exposure to harmful algal blooms, an emerging public health concern because of toxicity and increased incidence. We used the World Health Organization's International Classification of Disease (ICD) medical code specifying environmental exposure to harmful algal blooms to extract hospital visit records in New York State from 2008 to 2014. Using the ICD code, we identified 228 hospital visits with reported exposure to harmful algal blooms. They occurred all year long and had multiple principal diagnoses. Of all hospital visits, 94.7% were managed in the emergency department and 5.3% were hospitalizations. As harmful algal bloom surveillance increases, the ICD code will be a beneficial tool to public health only if used properly.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Proliferação Nociva de Algas , Adolescente , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Saúde Pública , Fatores Sexuais , Fatores Socioeconômicos , Adulto Jovem
7.
J Econ Entomol ; 108(3): 1363-70, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26470265

RESUMO

The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane (hybrids of Saccharum spp.) in Louisiana and Texas. Resistance to E. loftini was evaluated in 51 commercial and experimental cultivars of sugarcane, energycane (hybrids of Saccharum spp.), and sorghum [Sorghum bicolor (L.) Moench and hybrids of Sorghum spp.] in four replicated small plot field experiments from 2009 to 2012. A relative resistance ratio was developed to compare levels of susceptibility among cultivars based on the percentage of bored internodes and survival to adulthood. This index was able to separate cultivars into five resistance categories and provides a new method for comparing levels of resistance among cultivars. E. loftini pest pressure in 2009 was among the highest recorded with injury ranging from 55 to 88% bored internodes. Commercial sugarcane cultivar HoCP 85-845 was identified as resistant in three of four experiments, whereas HoCP 04-838 was identified as susceptible in all experiments. Of the five sugarcane cultivars in commercial production in the Rio Grande Valley of Texas, only TCP 87-3388 was categorized as resistant. Of the cultivars with potential for bioenergy production, all of the energycane cultivars demonstrated higher levels of resistance than high-biomass and sweet sorghum cultivars. Continued evaluation of cultivar resistance to E. loftini is important to development of effective integrated pest management strategies for this pest.


Assuntos
Herbivoria , Controle de Insetos/métodos , Mariposas/fisiologia , Saccharum/fisiologia , Animais , Cadeia Alimentar , Larva/crescimento & desenvolvimento , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Saccharum/genética , Texas
8.
Rev Environ Health ; 29(4): 363-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24918455

RESUMO

Providing sources of sustainable and quality potable water in Uganda is a significant public health issue. This project aimed at identifying and prioritizing possible actions on how sustainable high quality potable water in Uganda's water supply systems could be achieved. In that respect, a review of both the current water supply systems and government programs on drinking water in Uganda was completed. Aspects of quantity, quality, treatment methods, infrastructure, storage and distribution of water for different water systems were evaluated and compared with the existing water supply systems in the U.S., Latin America and the Caribbean, for purposes of generating feasible recommendations and opportunities for improvement. Uganda utilizes surface water, groundwater, and rainwater sources for consumption. Surface water covers 15.4% of the land area and serves both urban and rural populations. Lake Victoria contributes about 85% of the total fresh surface water. Potable water quality is negatively affected by the following factors: disposal of sewage and industrial effluents, agricultural pesticides and fertilizers, and surface run-offs during heavy rains. The total renewable groundwater resources in Uganda are estimated to be 29 million m3/year with about 20,000 boreholes, 3000 shallow-wells and 200,000 springs, serving more than 80% of the rural and slum communities. Mean annual rainfall in Uganda ranges from 500 mm to 2500 mm. Groundwater and rainwater quality is mainly affected by poor sanitation and unhygienic practices. There are significant regional variations in the accessibility of potable water, with the Northeastern region having the least amount of potable water from all sources. Uganda still lags behind in potable water resource development. Priorities should be placed mainly on measures available for improvement of groundwater and rainwater resource utilization, protection of watersheds, health education, improved water treatment methods and distribution in rural areas, and pollution control and monitoring. Implementing these changes can promote potable water accessibility especially to the poor populations living in rural and urban slum areas because they comprise the majority (80%) of Uganda's population.


Assuntos
Países em Desenvolvimento , Água Potável , Uganda , Qualidade da Água
9.
Front Plant Sci ; 14: 1274823, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046607

RESUMO

High head rice and low chalky grain percentages are key grain quality traits selected in developing rice cultivars. The objectives of this research were to characterize the phenotypic variation of head rice and chalky grain percentages in a diverse collection of rice accessions, identify single nucleotide polymorphism (SNP) markers associated with each of these traits using genome-wide association studies (GWAS), and identify putative candidate genes linked to the SNPs identified by GWAS. Diverse rice varieties, landraces, and breeding lines were grown at the Texas A&M AgriLife Research Center in Beaumont. Head rice percentages (HRP) and chalky grain percentages (CGP) of 195 and 199 non-waxy accessions were estimated in 2018 and 2019, respectively. Phenotypic data were analyzed along with 854,832 SNPs using three statistical models: mixed linear model (MLM), multi-locus mixed model (MLMM), and fixed and random model circulating probability unification (FarmCPU). Significant variations in HRP and CGP were observed between rice accessions. Two significant marker-trait associations (MTAs) were detected on chromosomes 1 and 2, respectively, based on best linear unbiased prediction (BLUP) values in 2018, while in 2019, one SNP was significantly associated with HRP in each of chromosomes 6, 8, 9, and 11, and two in chromosome 7. CGP was significantly associated with five SNPs located in chromosomes 2, 4, 6, and 8 in the 2018 study and ten SNPs in chromosomes 1, 2, 3, 4, 7, 8, 11, and 12 in the 2019 study. The SNPs are located within or linked to putative candidate genes involved in HRP and CGP. This study reports five and ten novel MTAs for HRP and CGP, respectively, while three and five MTAs co-located with previously reported quantitative trait loci for HRP and CGP, respectively. The validation of candidate genes for their roles in determining HRP and CGP is necessary to design functional molecular markers that can be used to effectively develop rice cultivars with desirable grain quality.

10.
Proc Biol Sci ; 279(1745): 4097-105, 2012 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-22874755

RESUMO

Agricultural production is under increasing pressure by global anthropogenic changes, including rising population, diversion of cereals to biofuels, increased protein demands and climatic extremes. Because of the immediate and dynamic nature of these changes, adaptation measures are urgently needed to ensure both the stability and continued increase of the global food supply. Although potential adaption options often consider regional or sectoral variations of existing risk management (e.g. earlier planting dates, choice of crop), there may be a global-centric strategy for increasing productivity. In spite of the recognition that atmospheric carbon dioxide (CO(2)) is an essential plant resource that has increased globally by approximately 25 per cent since 1959, efforts to increase the biological conversion of atmospheric CO(2) to stimulate seed yield through crop selection is not generally recognized as an effective adaptation measure. In this review, we challenge that viewpoint through an assessment of existing studies on CO(2) and intraspecific variability to illustrate the potential biological basis for differential plant response among crop lines and demonstrate that while technical hurdles remain, active selection and breeding for CO(2) responsiveness among cereal varieties may provide one of the simplest and direct strategies for increasing global yields and maintaining food security with anthropogenic change.


Assuntos
Dióxido de Carbono/metabolismo , Mudança Climática , Produtos Agrícolas/fisiologia , Grão Comestível/fisiologia , Abastecimento de Alimentos , Aclimatação , Agricultura/tendências , Produtos Agrícolas/metabolismo , Grão Comestível/metabolismo , Fotossíntese , Seleção Genética , Especificidade da Espécie
11.
Circ Res ; 104(9): 1085-94, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19342603

RESUMO

Impaired insulin signaling via phosphatidylinositol 3-kinase/Akt to endothelial nitric oxide synthase (eNOS) in the vasculature has been postulated to lead to arterial dysfunction and hypertension in obesity and other insulin resistant states. To investigate this, we compared insulin signaling in the vasculature, endothelial function, and systemic blood pressure in mice fed a high-fat (HF) diet to mice with genetic ablation of insulin receptors in all vascular tissues (TTr-IR(-/-)) or mice with genetic ablation of Akt1 (Akt1-/-). HF mice developed obesity, impaired glucose tolerance, and elevated free fatty acids that was associated with endothelial dysfunction and hypertension. Basal and insulin-mediated phosphorylation of extracellular signal-regulated kinase 1/2 and Akt in the vasculature was preserved, but basal and insulin-stimulated eNOS phosphorylation was abolished in vessels from HF versus lean mice. In contrast, basal vascular eNOS phosphorylation, endothelial function, and blood pressure were normal despite absent insulin-mediated eNOS phosphorylation in TTr-IR(-/-) mice and absent insulin-mediated eNOS phosphorylation via Akt1 in Akt1-/- mice. In cultured endothelial cells, 6 hours of incubation with palmitate attenuated basal and insulin-stimulated eNOS phosphorylation and NO production despite normal activation of extracellular signal-regulated kinase 1/2 and Akt. Moreover, incubation of isolated arteries with palmitate impaired endothelium-dependent but not vascular smooth muscle function. Collectively, these results indicate that lower arterial eNOS phosphorylation, hypertension, and vascular dysfunction following HF feeding do not result from defective upstream signaling via Akt, but from free fatty acid-mediated impairment of eNOS phosphorylation.


Assuntos
Pressão Sanguínea , Endotélio Vascular/enzimologia , Hipertensão/enzimologia , Resistência à Insulina , Insulina/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Transdução de Sinais , Animais , Células Cultivadas , Gorduras na Dieta , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Células Endoteliais/enzimologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Inibidores Enzimáticos/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Intolerância à Glucose/enzimologia , Intolerância à Glucose/fisiopatologia , Hipertensão/etiologia , Hipertensão/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Obesidade/enzimologia , Obesidade/fisiopatologia , Ácido Palmítico/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/deficiência , Proteínas Proto-Oncogênicas c-akt/genética , Receptor de Insulina/deficiência , Receptor de Insulina/genética , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Vasoconstrição , Vasoconstritores/farmacologia , Vasodilatação , Vasodilatadores/farmacologia
12.
Arch Environ Contam Toxicol ; 61(3): 530-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21136249

RESUMO

Indoor air polychlorinated biphenyl (PCB) concentrations were measured in upstate New York as part of a nonoccupational exposure investigation. The adjacent study communities contain numerous sites of current and former PCB contamination, including two capacitor-manufacturing facilities. Indoor air PCB concentrations in the study area homes were not significantly different than in the comparison area homes. Total PCB concentrations in the study area homes ranged from 0.3 to 114.3 ng/m(3) (median 7.9). For the comparison area homes, concentrations ranged from 0.3 to 233.3 ng/m(3) (median 6.8). No correlations were found between PCB concentrations in indoor and outdoor air, with indoor concentrations generally 20 times higher than outdoor concentrations. Of the home characteristics cataloged, the presence of fluorescent lights was significantly associated with total PCB concentration in the study area only. The indoor PCB concentrations measured in this study are similar to those in other communities with known PCB-contaminated sites and similar to levels reported in other locations from the northeastern United States.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento Ambiental/métodos , Bifenilos Policlorados/análise , Rios , Habitação , Modelos Lineares , New York
13.
Environ Monit Assess ; 175(1-4): 487-99, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20556645

RESUMO

Polychlorinated biphenyls (PCBs) were measured in raw and finished drinking water at seven Public Water Systems (PWSs) along the Hudson River as part of a baseline monitoring program prior to the extensive sediment dredging of the Upper Hudson River. Water samples were either analyzed using an Aroclor method (based on USEPA Method 508) or a congener method (Modified Green Bay Mass Balance Method). Using the congener-based method, raw water concentrations ranged from <9.3 to 164.3 ng/L and finished water concentrations ranged from <9.3 to 186.6 ng/L. Using the Aroclor method, finished water concentrations ranged from <5.0 to 200.9 ng/L. Most finished water samples above 73.0 ng/L were from a PWS with wells drilled near the river. Excluding the well data, total PCB concentrations in raw water at systems in the Upper River were similar to concentrations at systems in the Lower River, though the congener patterns differed. Paired comparison of total PCB concentrations using the two analytical methods showed good agreement, although raw water showed a different relationship than finished water.


Assuntos
Bifenilos Policlorados/análise , Rios/química , Abastecimento de Água/análise , Monitoramento Ambiental , Estados Unidos
14.
Nat Commun ; 12(1): 7163, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34887412

RESUMO

Future rice systems must produce more grain while minimizing the negative environmental impacts. A key question is how to orient agricultural research & development (R&D) programs at national to global scales to maximize the return on investment. Here we assess yield gap and resource-use efficiency (including water, pesticides, nitrogen, labor, energy, and associated global warming potential) across 32 rice cropping systems covering half of global rice harvested area. We show that achieving high yields and high resource-use efficiencies are not conflicting goals. Most cropping systems have room for increasing yield, resource-use efficiency, or both. In aggregate, current total rice production could be increased by 32%, and excess nitrogen almost eliminated, by focusing on a relatively small number of cropping systems with either large yield gaps or poor resource-use efficiencies. This study provides essential strategic insight on yield gap and resource-use efficiency for prioritizing national and global agricultural R&D investments to ensure adequate rice supply while minimizing negative environmental impact in coming decades.

15.
Sci Total Environ ; 394(1): 90-102, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18280543

RESUMO

An investigation was carried out in the New York City Watershed for the presence of selected pharmaceuticals. In four seasonal sampling events between August 2003 and May 2004, surface water was collected from eight reservoir keypoints and effluent was collected from four wastewater treatment plants. We evaluated the following twelve compounds: amoxicillin, atenolol, caffeine, carbamazepine, cephalexin, estrone, 17alpha-ethinylestradiol, 17beta-estradiol, ibuprofen, sulfamethoxazole, trimethoprim, and valproic acid. In the treated effluents, carbamazepine was detected most frequently (100%; concentration range: 22-551 ng/L), followed by atenolol (94%; ND - 14,200 ng/L), trimethoprim (83%; ND - 37,000 ng/L), ibuprofen (61%; ND - 14,600 ng/L), and caffeine (49%; ND - 37,200 ng/L), while estrone was detected once (56 ng/L). In the reservoir keypoint samples, only ibuprofen (2.5%; ND - 932 ng/L) and caffeine (2.9%; ND - 177 ng/L) were detected. The other analytes were not detected in any sample. It is expected that investigation of other wastewater treatment plants in the New York City Watershed would show that their effluents are also a potential source of pharmaceuticals, but that these pharmaceuticals are unlikely to be detected in the Watershed's surface waters.


Assuntos
Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Delaware , Monitoramento Ambiental , Cidade de Nova Iorque , Estações do Ano , Eliminação de Resíduos Líquidos , Poluição da Água/análise
16.
Arch Environ Contam Toxicol ; 54(3): 363-71, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17879110

RESUMO

Outdoor air polychlorinated biphenyl (PCB) concentrations were measured in upstate New York as part of a nonoccupational exposure investigation. The adjacent study communities of Hudson Falls and Fort Edward contain numerous sites of current and former PCB contamination, including two capacitor-manufacturing facilities. Outdoor air PCB concentrations in the study municipalities were significantly higher than in the comparison municipality of Glens Falls. Total PCB concentrations in the study area ranged from 0.102 to 4.011 ng/m(3) (median: 0.711 ng/m(3)). For the comparison area, concentrations ranged from 0.080 to 2.366 ng/m(3) (median: 0.431 ng/m(3)). Although our sampling was not designed to identify point sources, the presence of PCB-contaminated sites in the study area likely contributed to this observed difference in concentration. While elevated relative to the comparison area, total PCB concentrations in the study area are lower than those in other communities with known PCB-contaminated sites, and similar to levels reported in other locations from the northeastern United States.


Assuntos
Poluentes Atmosféricos/análise , Bifenilos Policlorados/análise , Monitoramento Ambiental , New York , Rios , Temperatura , Vento
17.
Nat Food ; 3(7): 493-494, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-37117940
18.
Sci Rep ; 7(1): 14858, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29093514

RESUMO

The CO2 fertilization effect is a major source of uncertainty in crop models for future yield forecasts, but coordinated efforts to determine the mechanisms of this uncertainty have been lacking. Here, we studied causes of uncertainty among 16 crop models in predicting rice yield in response to elevated [CO2] (E-[CO2]) by comparison to free-air CO2 enrichment (FACE) and chamber experiments. The model ensemble reproduced the experimental results well. However, yield prediction in response to E-[CO2] varied significantly among the rice models. The variation was not random: models that overestimated at one experiment simulated greater yield enhancements at the others. The variation was not associated with model structure or magnitude of photosynthetic response to E-[CO2] but was significantly associated with the predictions of leaf area. This suggests that modelled secondary effects of E-[CO2] on morphological development, primarily leaf area, are the sources of model uncertainty. Rice morphological development is conservative to carbon acquisition. Uncertainty will be reduced by incorporating this conservative nature of the morphological response to E-[CO2] into the models. Nitrogen levels, particularly under limited situations, make the prediction more uncertain. Improving models to account for [CO2] × N interactions is necessary to better evaluate management practices under climate change.


Assuntos
Dióxido de Carbono/farmacologia , Oryza/crescimento & desenvolvimento , Mudança Climática , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Modelos Biológicos , Nitrogênio/farmacologia , Oryza/efeitos dos fármacos , Folhas de Planta/anatomia & histologia
19.
Water Res ; 72: 28-39, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25466637

RESUMO

On-site wastewater treatment systems (OWTSs or septic systems) are designed to treat and dispose effluents on the same property that produces the wastewater. Approximately 25% of the U.S. population is served by such facilities. Nevertheless, studies on the treatment efficiency and discharge of organic contaminants through septic effluents are lacking. This pilot study showed the occurrence of organic contaminants including pharmaceuticals and personal care products (PPCPs), perfluoroalkyl surfactants (PFASs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in septic effluents, adjacent lake water samples, household drinking water in homes that use lake water or a well adjacent to the lake as a source of drinking water, and offshore lake water samples. Septic effluent as well as lake and tap water samples were collected from several households with OWTSs around Skaneateles Lake located in central New York. The advanced on-site systems were installed in some households for the purpose of limiting nutrient levels in the effluent to protect the local surface water. Additionally, because many of these systems serve homes with limited land, advanced treatment systems were needed. The median concentrations of ten PPCPs (ranged from 0.45 to 388 ng/L) and eleven PFASs (ranged from 0.20 to 14.6 ng/L) in septic water were significantly higher (p ≤ 0.01) than in lake water samples. The median concentrations of PPCPs and PFASs in lake and tap water samples were not significantly different (p ≥ 0.65). The median concentrations of ∑PBDEs in septic, lake, and tap water samples were 7.47, 3.49, and 2.22 ng/L, respectively, and those for ∑PCBs were 33.1, 29.2, and 28.6 ng/L, respectively. The mass flux of PPCPs (i.e. the mass flow of PPCPs per unit area per unit time) through the disposal of treated septic effluent from textile biofilter and aerobic treatments to the dispersal unit ranged from 12 (carbamazepine) to 66900 µg/m(2)/day (caffeine) whereas that for PFASs ranged from 7.0 (perfluorobutanesulfonate) to 833 µg/m(2)/day (perfluorooctanoic acid). Based on the ratio of measured concentrations and method detection limit, triclocarban, perfluorooctanoic acid, and perfluorooctanesulfonate have the potential to be used as chemical tracers of septic water contamination in Skaneateles Lake. The median concentrations of atenolol, a beta-blocker drug, in septic water were significantly (ρ = 0.86, p = 0.01) correlated with enterococci counts.


Assuntos
Produtos Domésticos/análise , Compostos Orgânicos/análise , Preparações Farmacêuticas/análise , Águas Residuárias/química , Purificação da Água/métodos , Lagos/química , New York , Projetos Piloto , Águas Residuárias/microbiologia
20.
Environ Pollut ; 123(3): 399-402, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12667768

RESUMO

A study to try to better understand the interactions between various air contaminants and acute asthma exacerbations is described. The study evaluates temporal associations between a panel of air contaminants and acute asthmatic exacerbations as measured by emergency room visits for asthma in communities in the Bronx and Manhattan in New York City (NYC). In addition, ambient levels of various air pollutants in two NYC communities are being compared. Almost 2 years of daily data have been collected for most of the air contaminants to be investigated. The air contaminants measured include gaseous compounds (ozone, sulfur dioxide, nitrogen oxides, aldehydes, nitrous acid, nitric acid, hydrochloric acid and ammonia), particulate matter components (metals, elemental and organic carbon, sulfate, hydrogen ion, pollen, mold spores and particle mass and number).


Assuntos
Poluentes Atmosféricos/análise , Asma/etiologia , Emergências , Monitoramento Ambiental/métodos , Doença Aguda , Aldeídos/análise , Amônia/análise , Carbono/análise , Humanos , Ácido Clorídrico/análise , Metais/análise , Cidade de Nova Iorque , Ácido Nítrico/análise , Óxidos de Nitrogênio/análise , Ácido Nitroso/análise , Ozônio/análise , Pólen , Esporos , Dióxido de Enxofre/análise
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