Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
J Biosci ; 462021.
Artículo en Inglés | MEDLINE | ID: mdl-33859067

RESUMEN

Phytic acid or Myo-inositol hexakisphosphate is an essential compound for the rice plants. It remains in the form of phytate, a mixed salt of different mineral cations, in the seeds. The phytate breaks down during germination and provides the inorganic phosphorus and mineral ions to the seedlings. However, humans do not get the benefit of those essential ions from rice consumption due to the absence of phytase in the gut. We envisaged down-regulating ITPK, the gene behind the phytic acid biosynthesis so that its low amount would facilitate a greater amount of free mineral ions in the endosperm. Since there are six homologues of rice ITPK, we studied their expression in seeds. Additionally, we undertook an in-silico analysis of the homologous proteins. Considering the results, we selected ITPK-2 for its RNAi-mediated embryo-specific down-regulation to obtain the low phytate rice. We obtained a 37% reduction of phytic acid content accompanied by a nearly three-fold enhancement of inorganic phosphorus in the transgenic seeds. Additionally, the iron and zinc content increased in polished rice grains compared to the wild type. The results also showed that reduced phytic acid content did not affect the germination potential and seedling growth of the transgenic rice.


Asunto(s)
Grano Comestible/metabolismo , Oryza/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Ácido Fítico/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Grano Comestible/anatomía & histología , Germinación , Hordeum/genética , Inositol/metabolismo , Minerales/metabolismo , Oryza/anatomía & histología , Oryza/genética , Fósforo/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Plantas Modificadas Genéticamente/anatomía & histología , Regiones Promotoras Genéticas , Interferencia de ARN
2.
Eur J Histochem ; 64(1)2020 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-31941265

RESUMEN

The seed morphology of three Pseudocereal Grains (PSCg), i.e. quinoa (Chenopodium quinoa Willd, Chenopodiaceae), buckwheat (Fagopyrum esculentum Moench, Polygonaceae) and amaranth (Amaranthus caudatus L., Amaranthaceae) was studied by light microscopy (LM) and Environmental Scanning Electron Microscopy coupled with Energy Dispersive Spectroscopy (ESEM-EDS). LM was used with visible light to evaluate either unstained sections or sections stained with Azan mixture and with fluorescent light. The aim of the study was to compare the architecture of the three seeds in order to connect their morphology with nutrient localization. The Azan staining allowed for the visualization of the seed coat, the embryo - with its shoot apical meristem - and the radicle cell layers, whereas the use of fluorescent microscopy identified the cells rich in phenolic compounds. Finally, the ESEM-EDS analysis revealed that the seed coat of the quinoa was thinner than that of amaranth or buckwheat. In all PSCg, starch granules appeared to be located in large polygonal cells, surrounded by a thin cell wall. Several globoids of proteins were observed in the embryo cells. In the radicle section, the vascular bundles of the procambium were evident, while Amaranth only showed a consistent layer of calcium crystals, located between the embryo and the perysperm. The morphological differences of the three PSCg were discussed in the context of their structural resistance to processing technologies which impact on nutritional value of derived foods.


Asunto(s)
Amaranthus/anatomía & histología , Chenopodium quinoa/anatomía & histología , Grano Comestible/anatomía & histología , Fagopyrum/anatomía & histología , Semillas/anatomía & histología , Amaranthus/embriología , Chenopodium quinoa/embriología , Grano Comestible/embriología , Fagopyrum/embriología , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Semillas/embriología
3.
PLoS One ; 13(12): e0208104, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30507965

RESUMEN

The process of rice domestication has been studied for decades based on changing morphological characteristics in assemblages of both macroremains, such as charred seeds and spikelet bases, and microremains, such as phytoliths, esp. bulliform and double-peaked phytoliths. The applicability of these indicators in determining if a specific assemblage is wild or domesticated, however, is rarely discussed. To understand the significance of these indicators in the determination of domestication, we collected 38 archaeological samples from eight Neolithic sites, dating from 10-2ka BP, in the lower Yangtze River region to analyze and compare the changes of these different indicators over eight thousand years. The data demonstrate that the comprehensive analysis of multiple indicators may be the best method to study the process of rice domestication developed thus far. An assemblage of rice remains can be identified as domesticated forms if they meet the following criteria simultaneously: 1) the proportion of domesticated-type bulliform phytoliths is more than 73%; and 2) the proportion of domesticated-type rice spikelet bases is higher than 75%. Furthermore, we found that each indicator tends to change steadily and gradually over time, and each stabilized at a different time, suggesting that the characteristics of domesticated rice developed slowly and successively. Changes of multiple indicators during the period between 10,000-2,000 yr BP indicate that the process of rice domestication in the lower Yangtze River region lasted as long as ca. 6,000 years during the Neolithic, and can be divided into three stages with the turning points in the middle Hemudu-late Majiabang culture (6,500-5,800yr BP) and the late Liangzhu culture (4,600-4,300yr BP).


Asunto(s)
Domesticación , Grano Comestible/historia , Fósiles , Oryza/anatomía & histología , Semillas/anatomía & histología , Arqueología , China , Grano Comestible/anatomía & histología , Historia Antigua , Ríos
4.
Animal ; 12(4): 750-756, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28835301

RESUMEN

Feeding dried distillers grains with solubles (DDGS), a feed high in fat and protein, to lactating beef cows can alter milk production and composition, resulting in improved pre-weaning growth of progeny. This alteration in milk profile may consequently alter the growth and carcass composition of the offspring after weaning. Therefore, Angus×Simmental steers (n=48) whose dams were fed one of two diets supplemented with either DDGS or soybean meal (CON) from calving to mid-lactation were placed in a feedlot to determine the effects of maternal nutrition during lactation on progeny development and carcass composition. Cow-calf pairs were allotted to two treatments at birth based on cow and calf BW, breed and age. Maternal diets were isocaloric (3.97 MJ/kg NEg) and consisted of rye hay supplemented with DDGS at 1% of BW (19.4% CP; 8.76% fat) or rye hay and corn silage supplemented with CON (11.7% CP; 2.06% fat). After conclusion of the treatments at 129 days postpartum, cow-calf pairs were comingled and managed as one group until weaning at 219 days postpartum. Steers were then transitioned to a common diet composed of 60% DDGS, 34% corn silage and 6% vitamin/mineral supplement and were placed indoors in individual pens with slatted floors. An intravenous glucose tolerance test (IVGTT) was performed 134 days after feedlot entry on 16 steers (CON, n=7; DDGS, n=9) to determine the effect of maternal diet on glucose and insulin sensitivity. Steers were slaughtered at a target BW of 645 kg. Categorical and continuous data were analyzed using the GLIMMIX and MIXED procedures of SAS, respectively. Steers from DDGS dams tended to be heavier on day 85 of feedlot finishing (P=0.09) compared with steers from CON dams. However, there were no differences in final weight, average daily gain, dry matter intake or efficiency (gain:feed, P⩾0.18). Maternal treatments did not affect progeny days on feed (P=0.15), despite a mean difference of 9 days in favor of DDGS. Glucose and insulin concentrations and area under the curve of progeny as measured by IVGTT were not affected by maternal diet (P⩾0.16). Maternal DDGS supplementation decreased marbling score (P=0.04), but did not influence carcass grading percentage or any other carcass characteristic (P⩾0.17).


Asunto(s)
Bovinos/fisiología , Suplementos Dietéticos/análisis , Grano Comestible/metabolismo , Carne/análisis , Alimentación Animal/análisis , Animales , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Grano Comestible/anatomía & histología , Femenino , Prueba de Tolerancia a la Glucosa/veterinaria , Lactancia , Glycine max/química , Destete
5.
PLoS One ; 8(3): e57853, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23469248

RESUMEN

Grain weight, an essential yield component, is under strong genetic control and markedly influenced by the environment. Here, by genome-wide association analysis with a panel of 94 elite common wheat varieties, 37 loci were found significantly associated with thousand-grain weight (TGW) in one or more environments differing in water and fertiliser levels. Five loci were stably associated with TGW under all 12 environments examined. Their elite alleles had positive effects on TGW. Four, two, three, and two loci were consistently associated with TGW in the irrigated and fertilised (IF), rainfed (RF), reduced nitrogen (RN), and reduced phosphorus (RP) environments. The elite alleles of the IF-specific loci enhanced TGW under well-resourced conditions, whereas those of the RF-, RN-, or RP-specific loci conferred tolerance to the TGW decrease when irrigation, nitrogen, or phosphorus were reduced. Moreover, the elite alleles of the environment-independent and -specific loci often acted additively to enhance TGW. Four additional loci were found associated with TGW in specific locations, one of which was shown to contribute to the TGW difference between two experimental sites. Further analysis of 14 associated loci revealed that nine affected both grain length and width, whereas the remaining loci influenced either grain length or width, indicating that these loci control grain weight by regulating kernel size. Finally, the elite allele of Xpsp3152 frequently co-segregated with the larger grain haplotype of TaGW2-6A, suggesting probable genetic and functional linkages between Xpsp3152 and GW2 that are important for grain weight control in cereal plants. Our study provides new knowledge on TGW control in elite common wheat lines, which may aid the improvement of wheat grain weight trait in further research.


Asunto(s)
Grano Comestible/genética , Sitios de Carácter Cuantitativo , Semillas/genética , Triticum/genética , Agua/fisiología , Alelos , Mapeo Cromosómico , Cromosomas de las Plantas , Cruzamientos Genéticos , Grano Comestible/anatomía & histología , Ambiente , Fertilizantes , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Haplotipos , Nitrógeno/deficiencia , Fenotipo , Fósforo/deficiencia , Carácter Cuantitativo Heredable , Semillas/anatomía & histología , Triticum/anatomía & histología , Agua/farmacología
6.
Nature ; 490(7420): 393-6, 2012 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-23034648

RESUMEN

Knowledge of the past variability of climate at high northern latitudes during astronomical analogues of the present interglacial may help to inform our understanding of future climate change. Unfortunately, long-term continuous records of ice-sheet variability in the Northern Hemisphere only are scarce because records of benthic (18)O content represent an integrated signal of changes in ice volume in both polar regions. However, variations in Northern Hemisphere ice sheets influence the Siberian High (an atmospheric pressure system), so variations in the East Asian winter monsoon (EAWM)--as recorded in the aeolian dust deposits on the Chinese Loess Plateau--can serve as a useful proxy of Arctic climate variability before the ice-core record begins. Here we present an EAWM proxy record using grain-size variations in two parallel loess sections representative of sequences across the whole of the Chinese Loess Plateau over the past 900,000 years. The results show that during periods of low eccentricity and precessional variability at approximately 400,000-year intervals, the grain-size-inferred intensity of the EAWM remains weak for up to 20,000 years after the end of the interglacial episode of high summer monsoon activity and strong pedogenesis. In contrast, there is a rapid increase in the EAWM after the end of most other interglacials. We conclude that, for both the 400,000-year interglacials, the weak EAWM winds maintain a mild, non-glacial climate at high northern latitudes for much longer than expected from the conventional loess and marine oxygen isotope records. During these times, the less-severe summer insolation minima at 65° N (ref. 4) would have suppressed ice and snow accumulation, leading to a weak Siberian High and, consequently, weak EAWM winds.


Asunto(s)
Calentamiento Global/historia , Calentamiento Global/estadística & datos numéricos , Cubierta de Hielo , Luz Solar , Regiones Árticas , China , Grano Comestible/anatomía & histología , Grano Comestible/crecimiento & desarrollo , Historia Antigua , Oxígeno/análisis , Oxígeno/metabolismo , Isótopos de Oxígeno , Tamaño de la Partícula , Lluvia , Estaciones del Año , Siberia , Viento
7.
Zhong Yao Cai ; 32(4): 500-3, 2009 Apr.
Artículo en Chino | MEDLINE | ID: mdl-19645231

RESUMEN

OBJECTIVE: To establish the standard for quality control of Fructus Hordei germinatus, Fructus Oryzae germinatus and Fructus Setariae germinatus. METHODS: The digital microscope and infrared spectroscopy were used in the pharmacognostical study. RESULTS: Distinguished differences were found on morphological and microscopical features of these three crude drugs. Whereas, their infrared spectrums were basically all the same. CONCLUSION: The study provides a convenient, effect method for the identification of these three medicinal materials.


Asunto(s)
Medicamentos Herbarios Chinos/química , Grano Comestible/anatomía & histología , Semillas/anatomía & histología , Medicamentos Herbarios Chinos/normas , Grano Comestible/ultraestructura , Hordeum/anatomía & histología , Hordeum/ultraestructura , Oryza/anatomía & histología , Oryza/ultraestructura , Farmacognosia , Polvos , Control de Calidad , Semillas/ultraestructura , Setaria (Planta)/anatomía & histología , Setaria (Planta)/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier
8.
J Econ Entomol ; 98(2): 395-401, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15889730

RESUMEN

The European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae), is one of the most important pests of corn, Zea mays L., because it consistently causes high loss of yield. A study was conducted in 2000-2002 at field sites in central and western Kentucky to investigate whether infestation by O. nubilalis differentially affects the production of high-oil corn compared with traditional field corn. Statistical differences in grain weight and percentage of oil content between the five infestation levels were significant at both locations and for all years. Average grain yield was reduced by 0.40% and average oil concentration by 0.011% for each 1% of damaged plants, and there was a strong correlation (0.76) between leaf damage ratings (i.e., Guthrie scale) and yield reduction. In general, corn planted at the early planting date tended to have a higher yield (grain weight) and oil content.


Asunto(s)
Aceite de Maíz/análisis , Lepidópteros/crecimiento & desarrollo , Enfermedades de las Plantas , Zea mays/crecimiento & desarrollo , Animales , Grano Comestible/anatomía & histología , Zea mays/química
9.
Cell Mol Biol Lett ; 9(2): 353-61, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15213814

RESUMEN

Immature, mature and endosperm-supported mature embryos of six triticale cultivars (BDMT-98-8S, Melez-2001, Mikham-2002, Presto, Tacettin Bey and Tatlicak-97) were cultured in vitro to compare the levels of callus induction and plant regeneration. Immature embryos, 15-18 days after anthesis, were aseptically excised and placed with the scutellum upwards on a callus culture medium consisting of Murashige and Skoog (MS) mineral salts supplemented with 2 mg l(-1) 2,4-dichlorophenoxyacetic acid (2,4-D). Mature embryos were aseptically excised from the imbibed seeds and placed scutellum up on MS medium supplement with 2 mg l(-1) 2,4-D. Endosperm-supported mature embryos were moved slightly in the imbibed mature seeds. The seeds with moved embryos were placed furrow downwards in dishes containing 8 mg l(-1) 2,4-D for callus induction. The developed calli and regenerated plants were maintained on hormone-free MS medium. Variability among the genotypes was observed for all the types of embryo culture. Immature embryos from "Presto" and endosperm-supported mature embryos from "Mikham 2002" had excellent regeneration capacities (92.0% and 97.3%, respectively) and the highest number of plants regenerated growing in soil (9 and 13, respectively). A comparison of the responses of the three explants used indicated that the endosperm-supported mature embryo was the most useful explant for plant regeneration in triticale.


Asunto(s)
Grano Comestible , Regeneración/fisiología , Grano Comestible/anatomía & histología , Grano Comestible/embriología , Grano Comestible/genética , Grano Comestible/crecimiento & desarrollo , Genotipo , Técnicas de Cultivo de Tejidos
10.
Arch. latinoam. nutr ; 46(3): 253-9, sept. 1996. ilus, tab
Artículo en Español | LILACS | ID: lil-217585

RESUMEN

Los parámetros químicos nutricionales con diferencias significativas (P=0.05) entre 10 variedades de sorgo, así como los rangos observados fueron: lípidos (2,76 a 3,75 por ciento), fibra cruda (60,6 a 64,7 por ciento), proteína (9,01 a 11,43 por ciento), extracto libre de nitrógeno (77,65 a 83,07 por ciento), almidón (60,65 a 64,20 por ciento), taninos (2.50 a 10.16 mg/g) y calorías totales (380 a 400 Kcal). El contenido de cenizas fue de 1,17 a 1,91 por ciento, la digestibilidad de la proteína (23,8 a 38,8 por ciento) y del almidón "in situ" (54,4 a 66,6 por ciento) no fueron estadísticamente diferentes. Entre los componentes químicos se tuvieron la siguientes correlaciones positivas con significancia: carbohidratos con calorías y grasa con fibra. Entre las correlaciones negativas destacan: grasa y fibra con carbohidratos, fibra con calorías, y digestibilidad "in vitro" de la proteína con taninos. Con la finalidad de tratar de obtener equivalencias analíticas para sustituir determinación anatómica o química; ya sea total o parcialmente, y facilitar la selección de variedades para distintos usos, y el procesamiento adecuado para el grano, se identifican correlaciones entre los datos químicos obtenidos en este estudio con las características anatómicas determinadas en un trabajo previo con las mismas muestras, detectándose 19 coeficientes significativos, de los que 8 fueron positivos y 11 negativos. entre las correlaciones con potencialidad de sustitución analítica destacan: tamaño del gránulo de almidón del endospermo córneo (EC) y longitud de las células del endospermo harinoso (EH), con cantidad de almidón; tamaño del cuerpo de proteína del EH, con digetibilidad de la proteína; largo y ancho de las células de aleurona con el contenido de fibra y de agua. Entre las correlaciones negativas sobresalen: tamaño del gránulo de almidón del EC y EH, con ceniza; tamaño del cuerpo de proteína del EC, con cantidad del almidón y con tamaño de los gránulos del mismo; largo y ancho de las células de la aleurona con carbohidratos y con calorías totales; y tamaño de las células de la aleurona con carbohidratos y con calorías totales; y tamaño de las células del mesocarpio con contenido de grasa


Asunto(s)
Animales Domésticos , Fibras de la Dieta/uso terapéutico , Grano Comestible/anatomía & histología , Grano Comestible/química , Grano Comestible/clasificación , Dieta , Lípidos/análisis , Ciencias de la Nutrición , Proteínas/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA