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981.
Francisco Otero‐Ferrer Lucía Molina Juan Socorro Hipólito Fernández‐Palacios Marisol Izquierdo Rogelio Herrera 《Journal of the World Aquaculture Society》2012,43(2):174-186
The importance of a suitable diet for reproduction has been recognized as one of the major factors in ornamental aquaculture. In seahorses, mysids have been described as preys in the wild. Also, Artemia has been usually employed for rearing fish, including syngnathids. Therefore, the aim of this work was to evaluate the effect of these live preys on the spawning quality of Hippocampus hippocampus. After 108 d, no differences were found in adults concerning all biological parameters evaluated, but broodstock fed on mysids showed better results than Artemia regarding number of spawning events (12 vs. 3), brood sizes (233.50 ± 59.04 vs. 68.00 ± 57.97 juveniles), and newborn seahorses standard length (10.61 ± 0.64 vs. 8.75 ± 1.32 mm). The better nutritional quality of mysids, overall in Docosahexanoic acid, could be one of the main responsible factors. However, mysids stock is conditioned by natural catches and rearing techniques are little known. Another alternative would be to combine them with Artemia in mixed diet. Further research must be done concerning mysids breeding techniques to delineate their employment as a sustainable prey for seahorse aquaculture. This trial showed for the first time the effect of mysids to enhance reproduction efficiency in H. hippocampus. 相似文献
982.
Elena Leon Fernando Piston Racha Aouni Peter R. Shewry Cristina M. Rosell Antonio Martin Francisco Barro 《Journal of Cereal Science》2010
Seven transgenic lines of a commercial wheat (Triticum aestivum L.) cultivar expressing transgenic subunits 1Ax1, 1Dx5 and 1Dy10, alone or in combination have been developed. Pasting properties were determined in these transgenic lines using a Rapid Visco Analyser (RVA) in order to determine the possible impact of HMW-GS transgene expression on the starch properties. Expression of the HMW-GS transgenes increased the proportions of the corresponding 1Ax, 1Dx and 1Dy subunits affecting significantly the ratios of HMW-GS:LMW-GS and x-type:y-type HMW-GS. Starch granule size distribution varied significantly among all transgenic lines, with the Anza control and transgenic line T616 (expressing subunits 1Ax1 and 1Dy10) showing the highest and the lowest percentage of B granules, respectively. All transgenic lines increased the water-binding capacities (WBC) at 25 °C and 90 °C. Line T606 (expressing subunits 1Ax1 and 1Dx5) and line T590 (expressing subunit 1Dy10) showed the lowest and the highest values for peak viscosity, respectively. Notably, lines expressing only transgenic x-type subunits (T580, T581 and T606), with high ratios of x-type:y-type HMW-GS, had low peak viscosities, final viscosities and breakdown viscosities. Line T590 had the highest breakdown viscosity while lines T606 and T581 had the lowest. 相似文献
983.
Adriana Schultz Moreira Laura González-Torres Raul Olivero-David Sara Bastida Juana Benedi Francisco J. Sánchez-Muniz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):290-298
The effects of diets including restructured meats (RM) containing Wakame or Nori on total liver glutathione status, and several
antioxidant enzyme gene expressions and activities were tested. Six groups of ten male growing Wistar rats each were fed a
mix of 85% AIN-93 M diet and 15% freeze-dried RM for 35 days. The control group (C) consumed control RM, the Wakame (W) and
the Nori (N) groups, RM with 5% Wakame and 5% Nori, respectively. Animals on added cholesterol diets (CC, CW, and CN) consumed
their corresponding basal diets added with cholesterol (2%) and cholic acid (0.4%). Alga and dietary cholesterol significantly
interact (P < 0.002) influencing all enzyme expressions but not activities. The cholesterol supplement decreased most enzyme expression
and activity. W-RM vs. C-RM increased (P < 0.05) expression of GPx, GR, Mn-SOD, and Cu,Zn-SOD and decreased that of catalase. N-RM vs. C-RM increased (P < 0.05) expression of catalase and Mn-SOD. GR activity increased in W-RM rats while SOD activity increased, but that of Se-GPx
decreased in N animals. W-RM increased total and reduced glutathione and decreased the redox index. CN diet induced significantly
lower plasma cholesterol levels (P < 0.001) than the CW diet. In conclusion, Nori-RM is a hypocholesterolemic food while Wakame-RM is an antioxidant food. This
should be taken into account when including this kind of RM as potential functional foods in human. 相似文献
984.
Francisco J López‐Ruiz Alejandro Pérez‐García Dolores Fernández‐Ortuño Diego Romero Emilio García Antonio de Vicente James KM Brown Juan A Torés 《Pest management science》2010,66(7):801-808
BACKGROUND: Cucurbit powdery mildew elicited by Podosphaera fusca (Fr.) U Braun & N Shishkoff limits crop production in Spain. Disease control is largely dependent on fungicides such as sterol demethylation inhibitors (DMIs). Fungicide resistance is an increasing problem in this pathogen. To overcome such risk, it is necessary to design rational control programmes based upon knowledge of field resistance. The aim of this study was to investigate the state of DMI sensitivity of Spanish P. fusca populations and provide tools for improved disease management. RESULTS: Using a leaf‐disc assay, sensitivity to fenarimol, myclobutanil and triadimenol of 50 isolates of P. fusca was analysed to determine discriminatory concentrations between sensitive and resistant isolates. As no clearly different groups of isolates could be identified, discriminatory concentrations were established on the basis of maximum fungicide field application rate, 100 mg L?1 for the three fungicides tested. Subsequently, a survey of DMI resistance was carried out in different provinces located in the south central area of Spain during the cucurbit growing seasons in 2002, 2003 and 2004. Examination of a collection of 250 isolates revealed that 23% were resistant to fenarimol and 7% to triadimenol, the provinces of Almería, Badajoz and Murcia being the locations with the highest frequencies of resistance. By contrast, no resistance to myclobutanil was found. CONCLUSION: Results show that fenarimol and, to a lesser extent, triadimenol have become less efficient for controlling cucurbit powdery mildew in Spain. These are important observations that should lead to reconsideration of the current disease management programmes. Copyright © 2010 Society of Chemical Industry 相似文献
985.
M. R. Costa J. P. M. Tanure K. M. A. Arruda J. E. S. Carneiro M. A. Moreira E. G. Barros 《Euphytica》2010,176(2):149-156
Anthracnose, rust and angular leaf spot caused by Colletotrichum lindemuthianum, Uromyces appendiculatus and Pseudocercospora griseola, respectively, are economically important diseases affecting the common bean production in Brazil. The BIOAGRO/UFV bean breeding
program developed Rudá-R, a dry bean line with ‘carioca’ seed type, containing the following disease resistance genes: Co-4, Co-6 and Co-10 (anthracnose); Ur-ON (rust) and Phg-1 (angular leaf spot). To transfer this combination of disease resistance genes present in Rudá-R to a black-seeded bean, a
backcrossing program aided by molecular markers was conducted, involving Rudá-R (donor genitor) and Diamante Negro (recurrent
genitor). Forty black-seeded BC3F3:6 lines were obtained with combinations of at least three markers linked to the indicated disease resistance genes. The lines
were evaluated for resistance to the three mentioned pathogens. Eight of the lines were homozygous and resistant to all four
evaluated races of C. lindemuthianum, but susceptible to race 2047. Four of the lines were homozygous and resistant to two races of U. appendiculatus. Twenty of the lines were homozygous and resistant to the two races of P. griseola tested. Grain yield of the BC3F3:6 lines was evaluated during the ‘winter’ season of 2006 and the ‘dry’ season of 2007. All lines had statistically equal or
higher yields than Rudá-R and Diamante Negro. Lines were identified that not only were high yielding but also resistant to
the three pathogens tested. These lines are potential genotypes for further testing and for release as new black common bean
varieties. 相似文献
986.
Juliana F. Mansur Amanda S. Santos Isabela B. Ramos Ednildo A. Machado Carlos R. Kaiser Hatisaburo Masuda Ana Maria H. Vasconcellos Mônica F. Moreira 《Pesticide biochemistry and physiology》2010,98(1):59-67
The effects of lufenuron, a chitin synthesis inhibitor, on oogenesis of Rhodnius prolixus were evaluated. Lufenuron-treated females lay eggs that are pink, but change color with time, acquiring a gray color. The eggs are abnormal in shape and become dehydrated. The percentage of eggs that hatch is decreased compared with the eggs from non-treated females. Digestion of ovaries with KOH yielded an insoluble white material, which was identified as chitin based on infrared and proton NMR spectral analyses along with standard commercial chitin. Glucosamine was detected by HPLC as the major product of acid hydrolysis of the KOH-insoluble material prepared from the ovary. Furthermore, presence of chitin in ovary was confirmed through fluorescent microscopy technique using a wheat germ agglutinin probe and by re-treatment with Streptomyces griseus chitinase that resulted in reduction of chitin-derived fluorescence. Micrographs of ovaries, from animals treated with lufenuron, showed some space between the follicular epithelium and the oocyte membrane. The in vivo incorporation of radioactive N-acetylglucosamine into chitin was inhibited by the presence of lufenuron. These data suggest that chitin present in ovaries of R. prolixus is an important component of the eggs and is involved in oogenesis. Exposure to lufenuron reduces the size of oocytes, number of chorionated oocytes, and also the incorporation of N-acetylglucosamine into chitin in the ovaries. In addition, lufenuron-induced oosorption, decreased the number of eggs laid, modified egg shape and color and reduced the viability of the eggs. Therefore, chitin or chitin-like component of ovaries may be considered as a new target for controlling R. prolixus populations. 相似文献
987.
Francisco B. Flores Paloma Sanchez-Bel María T. EstañMaría M. Martinez-Rodriguez Elena MoyanoBelén Morales Juan F. CamposJosé O. Garcia-Abellán María I. EgeaNieves Fernández-Garcia Félix RomojaroMaría C. Bolarín 《Scientia Horticulturae》2010
The possibility of applying grafting to improve fruit quality has been scarcely investigated. Different shoot tomato (Solanum lycopersicum) genotypes were grafted onto distinctly-different tomato rootstocks and the effect of the rootstock on two important fruit quality parameters, soluble solids content (SSC) and titratable acidity (TA), was studied under both non-saline and saline conditions. Increased SSC and TA in fruits from grafted plants grown under saline conditions were observed on different grafting combinations. One of these rootstocks (cv. Radja) was able to induce increases in both fruit yield and fruit quality traits of the scion. When recombinant inbred lines (RILs) from the crossing of the cultivated tomato and wild tomato (Solanum cheesmaniae) were tested as rootstocks, using the commercial hybrid ‘Boludo’ as scion, the rootstock also improved SSC and TA when grafted plants were grown under non-saline conditions. On the whole, these results show the effectiveness of grafting with respect to upgrading of fruit quality in tomato, which is of great importance as grafting is a rapid and efficient alternative to achieve this goal. 相似文献
988.
A Marques P Santos G Antunes A Chaveiro F Moreira da Silva 《Reproduction in domestic animals》2010,45(1):81-85
The objectives of this work are to determine if exogenous supplementation with α-tocopherol increases the in vitro fertilization (IVF) rate of bovine oocytes and improves viability of selected spermatozoa after 'swim-up'. The percentage of fertilized oocytes was significantly but negatively correlated ( r = −0.941, p < 0.01) with the concentration of α-tocopherol. The control resulted in 95% of fertilized oocytes, which decreased as follows: 25 μM α-tocopherol (α25) 86%, 50 μM α-tocopherol (α50) 74%, 100 μM α-tocopherol (α100) 66% and 200 μM α-tocopherol (α200) 56%. Relatively to sperm viability after 'swim-up' with α-tocopherol supplementation, this antioxidant proved to have a beneficial effect as its concentration increased up to α50, decreasing for the concentrations of α100 and α200. Control resulted in 83% of live cells and 16% of dead cells; α25 resulted in 88% of live cells and 12% of dead cells; α50 resulted in 91% of live cells and 9% of dead cells; α100 resulted in 67% of live cells and 33% of dead cells; and finally α200 resulted in 57% of live cells and 42% of dead cells. In summary, the present study allows to conclude that, in our conditions, supplementation with the antioxidant α-tocopherol in IVF of bovine oocytes has a detrimental effect on fertilization rates. Nevertheless, exogenous supplementation with α-tocopherol at a concentration of 50 mM in the sperm-TALP media during the 'swim-up' technique has a significant beneficial effect on the selected spermatozoa viability. 相似文献
989.
Mitrovich QM Tuch BB De La Vega FM Guthrie C Johnson AD 《Science (New York, N.Y.)》2010,330(6005):838-841
The evolutionary forces responsible for intron loss are unresolved. Whereas research has focused on protein-coding genes, here we analyze noncoding small nucleolar RNA (snoRNA) genes in which introns, rather than exons, are typically the functional elements. Within the yeast lineage exemplified by the human pathogen Candida albicans, we find--through deep RNA sequencing and genome-wide annotation of splice junctions--extreme compaction and loss of associated exons, but retention of snoRNAs within introns. In the Saccharomyces yeast lineage, however, we find it is the introns that have been lost through widespread degeneration of splicing signals. This intron loss, perhaps facilitated by innovations in snoRNA processing, is distinct from that observed in protein-coding genes with respect to both mechanism and evolutionary timing. 相似文献
990.
Francisco X. Aguilar Mihaela M. Cernusca Michael A. Gold Carla E. Barbieri 《Agroforestry Systems》2010,79(1):19-29
A study of frequency of consumption and familiarity with preparing chestnuts was conducted in the state of Missouri from 2003
to 2008. A conjoint analysis of chestnut attributes was completed in 2008 to expand on previous consumer preference research.
Information from final consumers was collected during the annual Missouri Chestnut Roast festival at the Horticulture and
Agroforestry Research Center in New Franklin, Missouri. The study tracks changes in frequency of consumption and consumer
familiarity with preparing chestnuts. The conjoint analysis evaluated pair-wise profiles to quantify the effects of origin,
production process and price on consumer preferences. Results show improvements in the frequency of consumption and familiarity
with cooking chestnuts in Missouri. Findings suggest the festival has influenced consumption patterns among return visitors.
The conjoint analysis identified locality of produce and organic certification to be major drivers behind consumer preferences.
Price is also an important attribute influencing consumer preferences. Conjoint analysis results indicate that chestnuts grown
in Missouri or the U.S. carrying an organic label can capture price premiums. 相似文献