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1.
Microb Ecol ; 82(1): 135-144, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33580815

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is becoming an increasingly important food crop. Understanding the microbiome of quinoa and its relationships with soil microorganisms may improve crop yield potential or nutrient use efficiency. Whether quinoa is a host or non-host of a key soil symbiont, arbuscular mycorrhizal fungi (AMF), is suddenly up for debate with recent field studies reporting root colonization and presence of arbuscules. This research seeks to add evidence to the mycorrhizal classification of quinoa as we investigated additional conditions not previously explored in quinoa that may affect root colonization. A greenhouse study used six AMF species, two AMF commercial inoculant products, and a diverse set of 10 quinoa genotypes. Results showed 0 to 3% quinoa root colonization by AMF when grown under greenhouse conditions. Across quinoa genotypes, AMF inoculant affected shoot dry weight (p = 0.066) and height (p = 0.031). Mykos Gold produced greater dry biomass than Claroideoglomus eutunicatum (27% increase), Rhizophagus clarus (26% increase), and within genotype CQ119, the control (21% increase). No treatment increased plant height compared to control, but Funneliformis mosseae increased height compared to C. eutunicatum (25% increase) and Rhizophagus intraradices (25% increase). Although quinoa plants were minimally colonized by AMF, plant growth responses fell along the mutualism-parasitism continuum. Individual AMF treatments increased leaf greenness in quinoa genotypes 49ALC and QQ87, while R. clarus decreased greenness in CQ119 compared to the control. Our research findings support the recommendation to classify quinoa as non-mycorrhizal when no companion plant is present and inconsistently mycorrhizal when conditional colonization occurs.


Asunto(s)
Chenopodium quinoa , Micorrizas , Bioensayo , Hongos , Micorrizas/genética , Raíces de Plantas
2.
J Dairy Sci ; 101(12): 10743-10749, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30292547

RESUMEN

Acid whey (AW) is the liquid co-product arising from acid-induced precipitation of casein from skim milk. Further processing of AW is often challenging due to its high mineral content, which can promote aggregation of whey proteins, which contributes to high viscosity of the liquid concentrate during subsequent lactose crystallization and drying steps. This study focuses on mineral precipitation, protein aggregation, and lactose crystallization in liquid AW concentrates (∼55% total solids), and on the microstructure of the final powders from 2 independent industrial-scale trials. These AW concentrates were observed to solidify either during processing or during storage (24 h) of pre-crystallized concentrate. The more rapid solidification in the former was associated with a greater extent of lactose crystallization and a higher ash-to-protein ratio in that concentrate. Confocal laser scanning microscopy analysis indicated the presence of a loose network of protein aggregates (≤10 µm) and lactose crystals (100-300 µm) distributed throughout the solidified AW concentrate. Mineral-based precipitate was also evident, using scanning electron microscopy, at the surface of AW powder particles, indicating the formation of insoluble calcium phosphate during processing. These results provide new information on the composition- and process-dependent physicochemical changes that are useful in designing and optimizing processes for AW.


Asunto(s)
Caseínas/química , Leche/química , Suero Lácteo/química , Animales , Fenómenos Químicos , Precipitación Química , Cristalización , Desecación , Alimentos en Conserva , Lactosa/química , Microscopía Electrónica de Rastreo , Proteínas de la Leche/análisis , Proteínas de la Leche/química , Polvos/química , Proteína de Suero de Leche/química
3.
Mol Genet Metab ; 113(4): 294-300, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25456742

RESUMEN

Mottled-dappled (Mo-dp) is a mouse model of Menkes disease caused by a large, previously uncharacterized deletion in the 5' region of Atp7a, the mouse ortholog of ATP7A. Affected mutants die in utero at embryonic day 17, and show bending and thickening of the ribs and distortion of the pectoral and pelvic girdles and limbs. To characterize this allele, we designed a custom 4x180K microarray on the mouse X chromosome and performed comparative genomic hybridization using extracted DNA from normal and carrier Mo-dp females, and identified an approximately 9 kb deletion. We used PCR to fine-map the breakpoints and amplify a junction fragment of 630 bp. Sequencing of the junction fragment disclosed the exact breakpoint locations and that the Mo-dp deletion is precisely 8990 bp, including approximately 2 kb in the promoter region of Atp7a. Western blot analysis of Mo-dp heterozygous brains showed diminished amounts of Atp7a protein, consistent with reduced expression due to the promoter region deletion on one allele. In heterozygous females, brain copper levels tended to be lower compared to wild type whereas neurochemical analyses revealed higher dihydroxyphenylacetic acid:dihydroxyphenylglycol (DOPAC:DHPG) and dopamine:norepinephrine (DA:NE) ratios compared to normal (P=0.002 and 0.029, respectively), consistent with partial deficiency of dopamine-beta-hydroxylase, a copper-dependent enzyme. Heterozygous females showed no significant differences in body weight compared to wild type females. Our results delineate the molecular details of the Mo-dp mutation for the first time and define novel biochemical findings in heterozygous female carriers of this allele.


Asunto(s)
Adenosina Trifosfatasas/genética , Proteínas de Transporte de Catión/genética , Modelos Animales de Enfermedad , Síndrome del Pelo Ensortijado/genética , Alelos , Animales , Western Blotting , Peso Corporal , Encéfalo/metabolismo , Hibridación Genómica Comparativa , Cobre/metabolismo , ATPasas Transportadoras de Cobre , Dopamina beta-Hidroxilasa/metabolismo , Femenino , Heterocigoto , Humanos , Síndrome del Pelo Ensortijado/metabolismo , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Eliminación de Secuencia , Cromosoma X/genética
4.
Front Nutr ; 11: 1394136, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39323567

RESUMEN

Climate change increases stressors that will challenge the resiliency of global agricultural production. Just three crops, wheat, maize, and rice, are estimated to sustain 50% of the caloric demand of the world population, meaning that significant loss of any of these crops would threaten global food security. However, increasing cropping system diversity can create a more resilient food system. One crop that could add diversity to wheat-dominated cropping systems in the inland Pacific Northwest is proso millet, a climate-resilient, small-seeded cereal crop that is highly water efficient, able to grow in low fertility soils, and has a desirable nutritional profile. Proso millet shows potential for adoption in this region due to its short growing season, compatibility with regional equipment, and environmental requirements, however US cultivars have been developed for the Great Plains and little research has been conducted outside of this region. To better understand the potential for adoption in the inland PNW, seven commercially available varieties were planted in a researcher-run trial in Pullman, WA and in a series of producer-run trials across the region in 2022. Samples were analyzed for mineral concentration (Zn, Fe, Cu, Mn, Mg, Ca, P, and K), seed morphology phenotypes (seed area, seed eccentricity, thousand seed weight, and seed color), and agronomic phenotypes (grain yield, plant height, days to heading, days to maturity, and percent emergence). Varieties from the researcher-run trial showed significant differences for all traits excluding percent emergence. Samples from producer-run trials showed differences by location for concentration of all minerals and for all seed morphology traits but were not analyzed for agronomic phenotypes. Samples from producer-run trials showed no difference by variety for mineral concentration but showed varietal differences for all seed morphology phenotypes. Most minerals were positively correlated with one another (0.28 < r < 0.92). Grain yield was negatively correlated with Zn (r = -0.55, p < 0.01) and was positively correlated with plant height (r = 0.62, p < 0.001), seed area (r = 0.45, p < 0.05), and thousand seed weight (r = 0.45, p < 0.05). Results from this study can inform variety selection for stakeholders interested in adopting proso millet in the inland PNW and can support future proso millet breeding efforts, particularly in this region.

5.
Plants (Basel) ; 13(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38794368

RESUMEN

The introduction of quinoa into new growing regions and environments is of interest to farmers, consumers, and stakeholders around the world. Many plant breeding programs have already started to adapt quinoa to the environmental and agronomic conditions of their local fields. Formal quinoa breeding efforts in Washington State started in 2010, led by Professor Kevin Murphy out of Washington State University. Preharvest sprouting appeared as the primary obstacle to increased production in the coastal regions of the Pacific Northwest. Preharvest sprouting (PHS) is the undesirable sprouting of seeds that occurs before harvest, is triggered by rain or humid conditions, and is responsible for yield losses and lower nutrition in cereal grains. PHS has been extensively studied in wheat, barley, and rice, but there are limited reports for quinoa, partly because it has only recently emerged as a problem. This study aimed to better understand PHS in quinoa by adapting a PHS screening method commonly used in cereals. This involved carrying out panicle-wetting tests and developing a scoring scale specific for panicles to quantify sprouting. Assessment of the trait was performed in a diversity panel (N = 336), and the resulting phenotypes were used to create PHS tolerance rankings and undertake a GWAS analysis (n = 279). Our findings indicate that PHS occurred at varying degrees across a subset of the quinoa germplasm tested and that it is possible to access PHS tolerance from natural sources. Ultimately, these genotypes can be used as parental lines in future breeding programs aiming to incorporate tolerance to PHS.

6.
Front Plant Sci ; 14: 1161165, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929178

RESUMEN

Introduction: Quinoa is a high-value, nutritious crop that performs well in variable environments, marginal soils, and in diverse crop rotations. Quinoa's many attributes make it an ideal crop for supporting human health in global communities and economies. To date, quinoa research has largely focused on traits in adult plants important for enhancing plant phenotypic plasticity, abiotic stress, disease resistance, and yield. Fewer studies have evaluated quinoa seed dormancy and suggest that most modern quinoa varieties have weak or no seed dormancy, and a narrow window of seed viability post-harvest. In other crops, diminished seed dormancy is a major risk factor for preharvest sprouting (PHS; germination on the panicle due to rain prior to harvest) and may also pose a similar risk for quinoa. Methods: This study (1) developed a dormancy screening assay to characterize seed dormancy strength in a large collection of quinoa varieties, (2) investigated if morphological variables including seed coat color, seed coat thickness, seed shape including eccentricity which evaluates the roundness or flatness of a seed, and other agronomic traits like crude protein content and seed moisture, contribute to quinoa seed dormancy, and (3) evaluated the use of a phenetic modeling approach to explore relationships between seed morphology and seed dormancy. Results: Dormancy screening indicated seed dormancy ranges in quinoa varieties from none to strong dormancy. Further, phenetic modeling approaches indicate that seed coat thickness and eccentricity are important morphological variables that impact quinoa seed dormancy strength. Conclusions: While dormancy screening and phenetic modeling approaches do not provide a direct solution to preventing PHS in quinoa, they do provide new tools for identifying dormant varieties as well as morphological variables contributing to seed dormancy.

7.
Front Plant Sci ; 14: 1101547, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36875583

RESUMEN

Quinoa (Chenopodium quinoa Willd.), a pseudocereal with high protein quality originating from the Andean region of South America, has broad genetic variation and adaptability to diverse agroecological conditions, contributing to the potential to serve as a global keystone protein crop in a changing climate. However, the germplasm resources currently available to facilitate quinoa expansion worldwide are restricted to a small portion of quinoa's total genetic diversity, in part because of day-length sensitivity and issues related to seed sovereignty. This study aimed to characterize phenotypic relationships and variation within a quinoa world core collection. The 360 accessions were planted in a randomized complete block design with four replicates in each of two greenhouses in Pullman, WA during the summer of 2018. Phenological stages, plant height, and inflorescence characteristics were recorded. Seed yield, composition, thousand seed weight, nutritional composition, shape, size, and color were measured using a high-throughput phenotyping pipeline. Considerable variation existed among the germplasm. Crude protein content ranged from 11.24% to 17.81% (fixed at 14% moisture). We found that protein content was negatively correlated with yield and positively correlated with total amino acid content and days to harvest. Mean essential amino acids values met adult daily requirements but not leucine and lysine infant requirements. Yield was positively correlated with thousand seed weight and seed area, and negatively correlated with ash content and days to harvest. The accessions clustered into four groups, with one-group representing useful accessions for long-day breeding programs. The results of this study establish a practical resource for plant breeders to leverage as they strategically develop germplasm in support of the global expansion of quinoa.

8.
J Food Sci ; 87(12): 5225-5239, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36331266

RESUMEN

Ten advanced breeding lines of quinoa were evaluated for their physicochemical and functional characteristics. These novel breeding lines were used in two model foods, including cookies and cooked grains, to understand the influence of their characteristics on the product quality. The cookies were baked using whole quinoa flour, and the quality attributes of texture, physical dimensions, and color were measured. The whole quinoa grains were cooked with water at a 1:4 (w/w) grain-to-water ratio, and quality attributes including water uptake (WU-G), bulk density (BD-G), and cooking loss (CL-G) were measured. Significant differences in the quality of both products as an impact of the breeding lines were observed. In baked cookies, the WAQ2 variety produced cookies with the lowest diameter, whereas cookies prepared with WAQ1 were significantly softer than other varieties. In terms of cooked quinoa, WAQ8 exhibited the highest WU-G while WAQ1 showed the highest CL-G. Correlations were observed between flour characteristics and final product quality. Cookie height was negatively correlated with protein content, whereas the water solubility index (WSI) of flours had a positive effect on the cookie hardness. The cooking characteristics of quinoa grains were found to be correlated with the thermal properties of whole quinoa flour. The results of this study will help determine the advanced breeding lines for release as commercial varieties and will also provide food processors with information to find suitable quinoa varieties for different food applications. PRACTICAL APPLICATION: New quinoa breeding lines have been developed to be grown in the climate conditions of Washington State. These varieties were characterized to find correlations with food quality for cookies and cooked grains. The results from this study will help farmers navigate among the quinoa varieties and help commercial food producers use the optimal quinoa variety for their specific food products.


Asunto(s)
Chenopodium quinoa , Chenopodium quinoa/química , Fitomejoramiento , Culinaria/métodos , Harina/análisis , Agua
9.
JBI Evid Synth ; 20(8): 2109-2116, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35971208

RESUMEN

OBJECTIVE: The objective of this review is to develop a definition of biofortification through the synthesis of food biofortification publications and to document the breadth of the research on this topic. INTRODUCTION: Biofortification of a food source is a human health intervention. Due to the varying definitions of this concept, biofortification can be difficult to describe. Originally, biofortification was defined as the use of plant breeding methods to produce staple foods dense in minerals and vitamins. Research using the term focused on mineral, vitamin, and protein improvement of staple foods. However, the field has expanded to include non-staple foods as well as different methodological approaches to biofortification (eg, transgenic, molecular breeding). Researchers require a broad overview of the evidence and consensus on a definition to ensure effective communication within this scientific community. INCLUSION CRITERIA: Inclusion criteria will be broad to ensure that existing definitions of biofortification are captured across the different areas of study in this field. The review will consider research published in English. Inclusion will not be limited by participant type, date of publication, or context. The concept will be strictly biofortification. METHODS: A broad search strategy will be utilized for AGRICOLA, AGRIS, Web of Science, PubAg, CINAHL, PubMed, Cochrane Library, Epistemonikos, JBI Evidence Synthesis, Google Scholar, and Washington State University Libraries' integrated catalog. A limited search for gray literature will be conducted. The data extracted will include study and author characteristics. Tables and figures will demonstrate the breadth of the evidence.


Asunto(s)
Biofortificación , Vitamina A , Humanos , Minerales , Literatura de Revisión como Asunto , Vitaminas , Washingtón
10.
Sci Data ; 9(1): 323, 2022 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-35725573

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is an herbaceous annual crop of the amaranth family (Amaranthaceae). It is increasingly cultivated for its nutritious grains, which are rich in protein and essential amino acids, lipids, and minerals. Quinoa exhibits a high tolerance towards various abiotic stresses including drought and salinity, which supports its agricultural cultivation under climate change conditions. The use of quinoa grains is compromised by anti-nutritional saponins, a terpenoid class of secondary metabolites deposited in the seed coat; their removal before consumption requires extensive washing, an economically and environmentally unfavorable process; or their accumulation can be reduced through breeding. In this study, we analyzed the seed metabolomes, including amino acids, fatty acids, and saponins, from 471 quinoa cultivars, including two related species, by liquid chromatography - mass spectrometry. Additionally, we determined a large number of agronomic traits including biomass, flowering time, and seed yield. The results revealed considerable diversity between genotypes and provide a knowledge base for future breeding or genome editing of quinoa.


Asunto(s)
Chenopodium quinoa , Metaboloma , Semillas , Chenopodium quinoa/química , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Sequías , Fitomejoramiento , Saponinas , Semillas/química , Semillas/metabolismo
11.
Plants (Basel) ; 10(3)2021 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33670959

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a culturally significant staple food source that has been grown for thousands of years in South America. Due to its natural drought and salinity tolerance, quinoa has emerged as an agronomically important crop for production in marginal soils, in highly variable climates, and as part of diverse crop rotations. Primary areas of quinoa research have focused on improving resistance to abiotic stresses and disease, improving yields, and increasing nutrition. However, an evolving issue impacting quinoa seed end-use quality is preharvest sprouting (PHS), which is when seeds with little to no dormancy experience a rain event prior to harvest and sprout on the panicle. Far less is understood about the mechanisms that regulate quinoa seed dormancy and seed viability. This review will cover topics including seed dormancy, orthodox and unorthodox dormancy programs, desiccation sensitivity, environmental and hormonal mechanisms that regulate seed dormancy, and breeding and non-breeding strategies for enhancing resistance to PHS in quinoa.

12.
J Food Sci ; 86(8): 3628-3644, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34190346

RESUMEN

American craft brewers are targeting barley malt as a novel source of flavor and as a means of differentiation. However, fundamental tools have only recently emerged to aid barley breeders in supporting this effort, such as the hot steep malt sensory method, a wort preparation method recently approved by the American Society of Brewing Chemists for evaluation of extractable malt flavor. The primary objective of this study was to determine if insights into beer liking and sensory attributes can be gained through hot steep malt sensory using an untrained panel of craft beer consumers (n = 95). We evaluated consumer acceptance of hot steep and beer samples of different barley genotypes using a 9-point hedonic scale, check-all-that-apply (CATA), and open comment during separate sensory panels. Beers brewed with Washington State University breeding lines (n = 4), selected for all-malt craft brewing, generally had higher consumer acceptance than the industry-standard control variety (CDC Copeland). Genotype had a significant influence on the consumer acceptance of beer aroma, appearance, taste/flavor, sweetness, and overall liking but only on hot steep appearance. Significant differences between genotypes were found for 18% (fruity and other) and 46% (chemical, citrus, earthy, fruity, stale, and sweet aromatic) of CATA attributes for the hot steep and beer panels, respectively. Hot steep and beer liking and sensory attributes had low correlation coefficients. For example, beer overall liking was negatively correlated with chemical (r = -0.338, p < 0.0001) and positively correlated with fruity (r = 0.265, p < 0.0001). This study demonstrates that untrained craft beer consumers can better differentiate among genotypes using beers than hot steep samples. PRACTICAL APPLICATION: In general, Washington State University barley breeding lines had higher consumer acceptance than the control variety, CDC Copeland. Each genotype had a distinctive beer flavor profile, such as 12WA_120.14 (fruity and sweet aromatic), which had the highest consumer acceptance ratings, and 10WA_107.43 (citrus), which has been released as the variety "Palmer." The results illustrate that the use of different barley genotypes presents varied sensory properties in the final beer and that particular malt and beer sensory attributes may influence consumer acceptance.


Asunto(s)
Cerveza , Hordeum , Cerveza/análisis , Comportamiento del Consumidor , Aromatizantes/análisis , Hordeum/genética , Humanos , Fitomejoramiento , Gusto
13.
Environ Entomol ; 50(4): 852-859, 2021 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-33960388

RESUMEN

Crop diversification often promotes farm sustainability. However, proper management of newly introduced crops is difficult when pests are unknown. Characterizing herbivore dynamics on new crops, and how they respond to agronomic factors, is crucial for integrated pest management. Here we explored factors affecting Lygus spp. (Hemiptera: Miridae) herbivores in quinoa crops of Washington State. Quinoa is a newly introduced crop for North America that has multiple varieties and a range of agronomic practices used for cultivation. Through arthropod surveys and discussions with growers, we determined that Lygus spp. was the most abundant insect herbivore and likely contributed to low quinoa yields in previous seasons. We assessed how different varieties (Pison and QQ74), irrigation regimes (present and not), and planting methods (direct-seeded and transplanted) affected Lygus population dynamics. Lygus phenology was correlated with timing of quinoa seed-set in July and August, corresponding to a period when quinoa is most susceptible to Lygus. Both irrigation and planting manipulations had significant effects on Lygus abundance. Irrigation reduced Lygus abundance compared with nonirrigated plots in 2018. Planting method had a significant effect on Lygus populations in both 2017 and 2018, but effects differed among years. Variety had a significant effect on Lygus abundance, but only in nonirrigated plots. Overall, our study shows that Lygus is a common insect herbivore in quinoa, and careful selection of variety, planting method, and irrigation regime may be key components of effective control in seasons where Lygus abundance is high.


Asunto(s)
Chenopodium quinoa , Hemípteros , Heterópteros , Animales , Herbivoria , Insectos , Dinámica Poblacional
14.
Front Nutr ; 7: 126, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32903386

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a pseudocereal celebrated for its excellent nutritional quality and potential to improve global food security, especially in marginal environments. However, minimal information is available on how genotype influences seed composition, and thus, nutritional quality. This study aimed to provide a baseline for nutritional quality of Washington grown quinoa and test the hypothesis that these samples contain adequate amounts of essential amino acids to meet daily requirements set by the World Health Organization (WHO). One hundred samples, representing commercial varieties and advanced breeding lines adapted to Washington State, were analyzed for content of 23 amino acids, as well as crude protein, ash, moisture, and crude fat. Mean essential amino acid values for Washington grown quinoa met the daily requirements for all age groups for all essential amino acids, except for the amount of leucine required by infants. We found that only nine genotypes met the leucine requirements for all age groups. A total of 52 and 94 samples met the lysine and tryptophan requirements for all age groups, respectively. Mean values for isoleucine, leucine, lysine, tryptophan, valine, and the sulfur and aromatic amino acids are higher for Washington grown samples than those reported previously reported in the literature. Our results show that not all Washington grown quinoa samples meet daily requirements of essential amino acids, and we identify limiting amino acids for the germplasm and environments investigated. This study provides the first report of leucine as a limiting amino acid in quinoa. Additional research is needed to better understand variation in quinoa nutritional composition, identify varieties that meet daily requirements, and explore how genotype, environment, and management interactions influence nutritional quality.

15.
Front Nutr ; 7: 605674, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33240922

RESUMEN

[This corrects the article DOI: 10.3389/fnut.2020.00126.].

16.
Plants (Basel) ; 9(1)2020 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-31936466

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a highly nutritious crop that is resilient to a wide range of abiotic stresses; however, sensitivity to high temperatures is regarded as an impediment to adoption in regions prone to heat waves. Heat stress is usually associated with a decrease in crop reproductive capacity (e.g., pollen viability), yet little is known about how leaf physiological performance of quinoa is affected by high temperatures. Several trials were conducted to understand the effect of high temperatures, without confounding stressors such as drought, on ten selected quinoa genotypes considered to encompass heat sensitive and heat tolerant plant material. Plants were grown under favorable temperatures and exposed to two temperature treatments over four consecutive days. The heat treatment simulated heat waves with maximum and minimum temperatures higher during the day and night, while the control treatment was maintained under favorable temperatures (maximum and minimum temperatures for 'Heat': 45/30 °C and 'Control': 20/14 °C). Leaf gas exchange (day), chlorophyll fluorescence (predawn and day) and dark respiration (night) were measured. Results show that most quinoa genotypes under the heat treatment increased their photosynthetic rates and stomatal conductance, resulting in a lower intrinsic water use efficiency. This was partly corroborated by an increase in the maximum quantum yield of photosystem II (Fv/Fm). Dark respiration decreased under the heat treatment in most genotypes, and temperature treatment did not affect aboveground biomass by harvest (shoot and seeds). These results suggest that heat stress alone favors increases in leaf carbon assimilation capacity although the tradeoff is higher plant water demand, which may lead to plant water stress and lower yields under non-irrigated field conditions.

17.
PLoS One ; 14(3): e0212852, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30893328

RESUMEN

The U.S. art museum sector is grappling with diversity. While previous work has investigated the demographic diversity of museum staffs and visitors, the diversity of artists in their collections has remained unreported. We conduct the first large-scale study of artist diversity in museums. By scraping the public online catalogs of 18 major U.S. museums, deploying a sample of 10,000 artist records comprising over 9,000 unique artists to crowdsourcing, and analyzing 45,000 responses, we infer artist genders, ethnicities, geographic origins, and birth decades. Our results are threefold. First, we provide estimates of gender and ethnic diversity at each museum, and overall, we find that 85% of artists are white and 87% are men. Second, we identify museums that are outliers, having significantly higher or lower representation of certain demographic groups than the rest of the pool. Third, we find that the relationship between museum collection mission and artist diversity is weak, suggesting that a museum wishing to increase diversity might do so without changing its emphases on specific time periods and regions. Our methodology can be used to broadly and efficiently assess diversity in other fields.


Asunto(s)
Arte , Diversidad Cultural , Museos , Humanos , Estados Unidos
18.
Plants (Basel) ; 7(4)2018 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-30501077

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a genetically diverse Andean crop that has earned special attention worldwide due to its nutritional and health benefits and its ability to adapt to contrasting environments, including nutrient-poor and saline soils and drought stressed marginal agroecosystems. Drought and salinity are the abiotic stresses most studied in quinoa; however, studies of other important stress factors, such as heat, cold, heavy metals, and UV-B light irradiance, are severely limited. In the last few decades, the incidence of abiotic stress has been accentuated by the increase in unpredictable weather patterns. Furthermore, stresses habitually occur as combinations of two or more. The goals of this review are to: (1) provide an in-depth description of the existing knowledge of quinoa's tolerance to different abiotic stressors; (2) summarize quinoa's physiological responses to these stressors; and (3) describe novel advances in molecular tools that can aid our understanding of the mechanisms underlying quinoa's abiotic stress tolerance.

19.
J Ethnobiol Ethnomed ; 13(1): 3, 2017 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-28086808

RESUMEN

The transverse harvest knife, also commonly called the finger or finger-bladed knife, has been utilized by rice farmers in southeast Asia for many centuries. The finger knife persisted in many traditional cultures long after the introduction of the sickle, a tool which provided farmers with the means to execute a much faster harvest. Several theories in interpretative archaeology have attempted to account for this rejection of more modern technological innovations. These theories, which include community-based social organization ideas and practical reasons for the continued use of the finger knife, are presented in this paper. Here I suggest an alternate theory based on a re-interpretation of existing research and fusion of existing theories: the primary reason for the historical and continued use of the finger knife is for seed selection through a centuries old tradition of plant breeding. Though I accept the accuracy of the practical and community-based, socio-cultural reasons for the use of the finger knife put forth by other authors, I suggest that seed selection and genetic improvement was the driving factor in the use of the finger knife. Indeed, intricate planting and harvesting rituals, which both ensured and encouraged varietal conservation and improvement co-evolved with the use of the finger knife as the primary harvest tool due to its unique ability to aid the farmer in the art and science of seed selection. When combined with previous ideas, this interpretative theory, based on the connection between ethnoagronomy and material culture, may provide a more complete picture of the story around the persistence of the finger knife in traditional rice-growing cultures in southeast Asia. I focus my theory on the terrace-building Ifugao people in the mountainous Cordillera region of northcentral Philippines; however, to put the use of the finger into a wider regional context, I draw from examples of the use of the finger knife in other traditional cultures throughout the region of southeast Asia.


Asunto(s)
Producción de Cultivos/instrumentación , Cultura , Etnobotánica/métodos , Oryza , Fitomejoramiento/métodos , Producción de Cultivos/métodos , Etnobotánica/instrumentación , Femenino , Humanos , Masculino , Filipinas , Semillas
20.
J Food Sci ; 82(10): 2387-2395, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28869289

RESUMEN

Starch characteristics significantly influence the functionality and end-use quality of cereals and pseudo-cereals. This study examined the composition and properties of starch from 11 pure varieties and 2 commercial samples of quinoa in relationship to the texture of cooked quinoa. Nearly all starch properties and characteristics differed among these samples. Results showed that total starch content of seeds ranged from 53.2 to 75.1 g/100 g apparent amylose content ranged from 2.7% to 16.9%; total amylose ranged from 4.7% to 17.3%; and the degree of amylose-lipid complex ranged from 3.4% to 43.3%. Amylose leaching ranged from 31 mg/100 g starch in "Japanese Strain" to 862 mg/100 g starch in "49ALC." "Japanese Strain" starch also exhibited the highest water solubility (4.5%) and the lowest swelling power (17). α-Amylase activity in "1ESP," "Col.#6197," "Japanese Strain," "QQ63," "Yellow Commercial," and "Red Commercial" (0.03 to 0.09 CU) were significantly lower than the levels of the other quinoa samples (0.20 to 1.16 CU). Additionally, gel texture, thermal properties, and pasting properties of quinoa starches were investigated. Lastly, correlation analysis showed that the quinoa samples with higher amylose content tended to yield harder, stickier, more cohesive, more gummy, and more chewy texture after cooking. A higher degree of amylose-lipid complex and amylose leaching were associated with softer and less chewy cooked quinoa TPA texture. Higher starch enthalpy correlated with firmer, more adhesive, more cohesive, and chewier texture. In sum, starch plays a significant role in the texture of cooked quinoa. PRACTICAL APPLICATION: The research determined starch characteristics among a diverse set of pure quinoa varieties and commercial samples, and identified the relationships between starch properties and cooked quinoa texture. The results can help breeders and food manufacturers to understand better the relationships among quinoa starch characteristics, cooked quinoa texture, and the best use of different cultivars.


Asunto(s)
Chenopodium quinoa/química , Almidón/química , Amilosa/química , Chenopodium quinoa/enzimología , Culinaria , Dureza , Calor , Semillas/química , Solubilidad , Termodinámica , alfa-Amilasas/química
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