An intensive hatchery rearing protocol for larvae of the bullseye puffer,Sphoeroides annulatus (Jenyns)     

Maria Isabel Abdo‐de la Parra  Armando García‐Ortega  Irma Martínez‐Rodríguez  Blanca González‐Rodríguez  Gabriela Velasco‐Blanco  Crisantema Hernández  Neil Duncan 《Aquaculture Research》2010,41(10):e554-e560

In this study bullseye puffer, Sphoeroides annulatus larvae were reared from hatching through to 1 or 2 months after weaning on an experimental scale in three replicate 600 L tanks and on three occasions during the spawning season (nine tanks in total). The rearing protocol used was green water (Nannochloropsis oculata and Isochrysis sp.) 100 000 cells mL^?1 from 0 to 11 days after hatch (DAH), 5–10 rotifers, Brachionus rotundiformis mL^?1 from 2 to 26 DAH, 0.1–1 Artemia mL^?1 from 21 to 34 DAH and weaning from 29 to 34 DAH. Survival to a month after weaning was 1%, a total of 3153 juveniles were produced with an average wet weight of 0.29 ± 0.07 g and a length of 27.5 ± 0.82 mm.  相似文献   

Fluorometric measurement of aflatoxin adsorbed on florisil in minicolumns.     

J Velasco 《Journal of the Association of Official Analytical Chemists》1975,58(4):757-763

Filter fluorometers have been adapted to measure the fluorescence intensity of aflatoxin absorbed on a Florisil layer in minicolumns. The relationship between concentration and intensity is near linear in the aflatoxin range from 10 to 100 ng. Although individual aflatoxin fractions cannot be resolved, since the measure is one of total intensity, fluorometric measurements advance the minicolumn screening procedure to a semiquantitative level. The detection of 1 ng aflatoxin B1 is well within the limits of a filter fluorometer with a photomultiplier detector. A precision, expressed as per cent coefficient of variation, ranging from 1.2 to 4.2%, was obtained for standard B1 columns.  相似文献   

A fine‐scale genetic linkage map reveals genomic regions associated with economic traits in walnut (Juglans regia)     

Mallikarjuna K. Aradhya  Dianne Velasco  Ji‐Rui Wang  Ramesh Ramasamy  Frank M. You  Chuck Leslie  Abhaya Dandekar  Ming‐Cheng Luo  Jan Dvorak 《Plant Breeding》2019,138(5):635-646

A genetic linkage map of walnut containing 2,220 single nucleotide polymorphisms (SNPs) in 16 linkage groups (LGs) was constructed using an F₁ mapping population from a cross between “Chandler” and “Idaho,” two contrasting heterozygous parents. Five quantitative yield traits, lateral fruitfulness, harvest date and three nut traits (shell thickness, nut weight and kernel fill) were then mapped on to linkage groups. A significant quantitative trait locus (QTL) in LG 11 with negative additive effects suggested heterozygote superiority in the expression of lateral bearing. A set of three QTLs explaining ~10% of the variation in harvest date was located in LG 1. Shell thickness, nut weight and kernel fill were under the control of two to three linked pleiotropic QTLs in LG 1 segregating from “Idaho.” The marginal positive additive effects of QTLs for harvest date, shell thickness and nut weight and small negative additive effects for kernel fill suggested that the QTLs had a marginal effect on the expression of these traits.  相似文献   

Genetic diversity of Orobanche cumana populations from Spain assessed using SSR markers     

R Pineda‐Martos  L Velasco  J Fernández‐Escobar  J M Fernández‐Martínez  B Pérez‐Vich 《Weed Research》2013,53(4):279-289

Orobanche cumana (sunflower broomrape) is found in Spain as an allochthonous species parasitising exclusively sunflower. For many years, it was distributed in the Guadalquivir Valley and Cuenca province, but in recent years, it has spread to new areas. The objective of this research was to study genetic diversity of O. cumana populations from Spain using robust co‐dominant molecular markers. Cluster analysis on a set of 50 populations using 15 microsatellite markers revealed the existence of two distant gene pools, one in Cuenca province and another one in the Guadalquivir Valley. Within each gene pool, both inter‐ and intrapopulation variability were extremely low. This population structure probably reflects a founder effect, with the two genetically distant gene pools deriving from separate introduction events. Different races occurred within the same gene pool, suggesting that current races might have evolved through mutation from a common genetic background. Most of the populations from new areas were identical to the populations from the Guadalquivir Valley. Only a few populations showed larger intrapopulation variation. In these cases, our results suggested the co‐existence of both gene pools within the same population, as well as the occurrence of genetic recombination between them. Genetic recombination between distant gene pools is an important mechanism for creating new variation, which might also have an effect on race evolution. These results will contribute to the establishment of improved crop breeding and management strategies for O. cumana control.  相似文献   

A dominant avirulence gene in Orobanche cumana triggers Or5 resistance in sunflower     

M I Rodríguez‐Ojeda  R Pineda‐Martos  L C Alonso  J Fernández‐Escobar  J M Fernández‐Martínez  B Pérez‐Vich  L Velasco 《Weed Research》2013,53(5):322-327

Orobanche cumana is a weed that grows as a root parasite on sunflower. In general, the O. cumana–sunflower parasitic system is regarded to follow the gene‐for‐gene model, although this has never been demonstrated at the genetic level in O. cumana. The Or5 dominant gene in sunflower confers resistance to O. cumana race E, but not to race F. The objective of this research was to study the inheritance of avirulence/virulence in crosses between plants of O. cumana lines classified as races E and F. Four race E and three race F lines were developed, from which four race E × race F cross‐combinations were made, in three cases including reciprocals. In all cases, F₁ seeds did not have the ability to parasitise sunflower line P‐1380 carrying the Or5 gene, indicating dominance of race E avirulence allele(s). Five F₂ populations comprising a total of 387 F_2:3 families were evaluated on sunflower line P‐1380. In all cases, one‐fourth of the F_2:3 families did not possess the ability to parasitise P‐1380 plants, suggesting that race E avirulence and race F virulence on P‐1380 are allelic and controlled by a single locus. This study demonstrated the gene‐for‐gene interaction in the O. cumana–sunflower parasite system and provided useful information to identify genes involved in O. cumana virulence. The approach followed in this research can contribute to define precisely races of the parasite on the basis of the presence of avirulence genes.  相似文献   

Environmental and genetic effects on yield and secondary metabolite production in Brassica rapa crops     

Francisco M  Cartea ME  Butrón AM  Sotelo T  Velasco P 《Journal of agricultural and food chemistry》2012,60(22):5507-5514

Twelve Brassica rapa varieties grown, such as turnip green and turnip top, were evaluated in seven environments to determine the environmental and genotypic variables that have an influence on crop production and on the content of glucosinolates and phenolic compounds. Factorial regression analysis showed that, in general, crop production was favored by high temperatures all along the crop cycle. However, the lack of a period of intense cold could be a limiting factor. The metabolite content seems to be regulated by extreme temperatures (daily maximum and minimum temperatures) rather than by average daily temperatures. With regard to genotypic covariables, turnip top production was significantly affected by traits related to the vegetative development and time to flowering. Meanwhile, turnip green production was largely affected by a sinapoyl derivative compound, which is a precursor of cell wall components. Cross-talk between glucosinolate biosynthesis and phenylpropanoid signaling pathways is suggested.  相似文献   

Profiling of resveratrol oligomers, important stress metabolites, accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola     

Mattivi F  Vrhovsek U  Malacarne G  Masuero D  Zulini L  Stefanini M  Moser C  Velasco R  Guella G 《Journal of agricultural and food chemistry》2011,59(10):5364-5375

In the Vitaceae, viniferins represent a relatively restricted group of trans-resveratrol oligomers with antifungal properties, thus enabling plants to cope with pathogen attack. The aim of this study was to perform isolation and structural characterization of the whole class of viniferins accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola . Infected leaves of resistant plants were collected 6 days after infection, extracted with methanol, and prepurified by flash chromatography using ENV+ and Toyopearl HW 40S resins. Further fractionation using normal-phase preparative chromatography and then reversed-phase preparative chromatography allowed isolation of 14 peaks. The isolated compounds were identified using advanced mass spectrometry techniques and extensive one- and two-dimensional nuclear magnetic resonance measurements, UV, CD, optical properties, and molecular mechanic calculations. The results demonstrated the presence in infected leaves of seven dimers (six stilbenes and one stilbenoid), of which four were new in grapevine (ampelopsin D, quadrangularin A, E-ω-viniferin, and Z-ω-viniferin), four trimers (three stilbenes and one stilbenoid), of which two (Z-miyabenol C and E-cis-miyabenol C) were new in grapevine, three tetramer stilbenoids, all new in grapevine, isohopeaphenol, ampelopsin H, and a vaticanol C-like isomer. The isolation of a dimer deriving from the condensation of (+)-catechin with trans-caffeic acid also indicated that other preformed phenolics are structurally modified in tissues infected with P. viticola.  相似文献   

Assessment the Health Hazard from 222Rn in Old Metalliferous Mines in San Luis, Argentina     

A. A. R. da Silva  D. L. Valladares  R. M. Anjos  H. Velasco  M. Rizzotto  E. M. Yoshimura 《Water, air, and soil pollution》2011,218(1-4):371-386

Radon levels in two old mines in San Luis, Argentina, are reported and analyzed. The radiation dose and environmental health risk of ²²²Rn concentrations to both guides and visitors were estimated. CR-39 nuclear track detectors were used for this purpose. The values for the ²²²Rn concentration at each monitoring site ranged from 0.43?±?0.04 to 1.48?±?0.12 kBq m^?3 in the Los Cóndores wolfram mine and from 1.8?±?0.1 to 6.0?±?0.5 kBq·m^?3 in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq m^?3 recommended by the International Commission on Radiological Protection. The patterns of the radon transport process revealed that the La Carolina gold mine can be interpreted as a gas confined into a single tube with constant cross-section and air velocity. Patterns of radon activity, taking into account the chimney-effect winds, were used to detect tributary currents of air from shafts or larger fissures along the main adit of the Los Cóndores mine, showing that radon can be used as an important tracer of tributary air currents stream out from fissures and smaller voids in the rock of the mine.  相似文献   

The nabicol: A horticultural crop in northwestern Spain     

Víctor?Manuel?RodríguezEmail author  María?Elena?Cartea  Guillermo?Padilla  Pablo?Velasco  Amando?Ordás 《Euphytica》2005,144(3):237-246

Nabicol (B. napus L. var. pabularia) is a traditional crop in the Northwest of Iberian Peninsula (South of Galicia and North of Portugal) where it is grown during the winter season on small farms and gardens using traditional varieties. A collection of 36 populations of nabicol from Galicia (northwestern Spain) was evaluated during 2002 and 2003 in two locations and two growing seasons (spring/summer and autumn/spring) for 28 agronomic and morphological traits. The objectives of this study were to: (i) evaluate a collection of nabicol landraces from northwestern Spain, (ii) determine the suitability of this germplasm as a summer crop and (iii) study the genetic diversity among local populations. Significant differences were observed among populations for most traits. Genotype × environment interaction was significant for most of them. Spring/summer growing season could be recommended for growing nabicol but resistance to Lepidoptera pests attacking Brassica crops should be improved. Most populations had an agronomic value similar to the commercial variety. The most promising variety for horticultural use was MBG-BRS0063, which showed the highest yield. Morphological and agronomic data were subjected to cluster analysis and four groups were defined with a group clustering most populations. The low genetic diversity could be explained because populations were collected in close geographical areas and the selection made by farmers was always for a horticultural use. These results give information about the diversity and breeding value of the nabicol Spanish germplasm, which could be useful in breeding programs.  相似文献   

Evaluation of Modified Amaranth Starch as Shell Material for Encapsulation of Probiotics     

Reyna Nallely Falfn Corts  Marcela Gaytn Martínez  Iigo Verdalet Guzmn  Silvia Lorena Amaya Llano  Carlos Raimundo Ferreira Grosso  Fernando Martínez Bustos 《Cereal Chemistry》2014,91(3):300-308

The objective of this study was to develop with thermoplastic extrusion amaranth starch derivatives and to characterize and evaluate their functionality as encapsulating agents of Bifidobacterium breve ATCC 15700 and Lactobacillus casei ATCC 334 during spray drying. The survival of both probiotics during storage at different water activities and at two storage temperatures, their viability in a food model system, and their tolerance to a simulated gastrointestinal tract were determined. Native amaranth starch was chemically modified to obtain phosphorylated, acetylated, and succinylated starch. Starch derivatives were reduced in viscosity, and the solubility in water was increased. In general, the modified amaranth starches and control corn starch did not provide good protection to both probiotics during storage at 25°C. However, there was excellent viability during storage at 4°C for both probiotics. Microcapsules showed a uniform coverage of the cells. Storage for 35 days at 25°C of blends of oat with succinylated amaranth microcapsules with probiotics had a lower reduction. Also, this succinylated amaranth starch containing probiotics showed a higher resistance to simulated gastrointestinal conditions. The results with food model systems supported the applicability of the modified starches.  相似文献