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61.
Israel Sánchez-Osorio Gloria López-Pantoja Antonia M. Paramio José L. Lencina Diego Gallego Luis Domínguez 《Journal of pest science》2016,89(1):59-68
Cerambyx welensii Küster is one of the greatest threats to Quercus suber L. and Quercus ilex L. in Spain. Efficient control methods for this species are currently being tested, and the use of traps baited with food-related products for their monitoring and control has been proposed. Cerambyx welensii adults prefer to colonize old or decayed trees, in which cortical exudates frequently release fermentation odors. Fermentation-related compounds, such as ethanol, have been cited as attractants to various hardwood woodborers (as Cerambyx cerdo L.), used either alone or sometimes in combination with other host odors. In this work, we conducted field experiments to ascertain whether chemical blends mimicking fermentation odors were attractive for C. welensii. To this end, we used three types of traps (multiple funnel, cross-vane and single-funnel) baited with six synthetic blends including one or more fermentation-related chemicals (ethanol, ethyl acetate, 3-methyl-1-butanol, acetaldehyde, 2-methyl-1-propanol and 2-methyl-1-butanol), various food-related products (beer, melon and red wine mixed with peach juice) and host monoterpenes (α-pinene, β-pinene, limonene, α-phellandrene and camphene). At high release rates (5–11 g/day), various synthetic blends proved attractive irrespective of trap type. Our results contribute to understand the impact of volatile organic compounds in host selection by woodborers infesting deciduous trees. The results hold promise for optimizing trapping strategies to control C. welensii within an integrated pest management framework. 相似文献
62.
Screening brassicaceous plants as biofumigants for management of Phytophthora cinnamomi oak disease 下载免费PDF全文
Brassicaceous plants rich in glucosinolates have been used as biofumigants for the management of soilborne pathogens. Efficacy of Brassica plant tissue has mainly been attributed to toxic isothiocyanates released upon the hydrolysis of glucosinolates. Management of Phytophthora cinnamomi, the causal agent of oak root rot in rangeland ecosystems using biofumigation, is promising, but requires further validation. The biofumigation activity of 14 brassicaceous plants was evaluated under experimental conditions. All evaluated plants rich in sinigrin suppressed (100%) the mycelial growth of P. cinnamomi, while plants rich in aromatic or other aliphatic glucosinolates had little or no suppressive effect. Simulating soil amendment in field conditions, the effects on natural soil artificially infested with P. cinnamomi chlamydospores were examined with Brassica juncea, Eruca vesicaria and Lepidium sativum, three species with different glucosinolate profiles. Only B. juncea decreased the viability of chlamydospores significantly in comparison with untreated soil only 1 day after biofumigation, whereas E. vesicaria needed 8 days to reach significance and L. sativum had no effect at all. Despite the decreases in soil inoculum, biofumigation with B. juncea did not prevent the root infections in a highly susceptible host (Lupinus luteus). However, biofumigation with plants rich in sinigrin, such as B. juncea, decreased P. cinnamomi soil inoculum under the experimental minimum threshold for oak disease expression. Although biofumigation should be considered as an effective measure to be incorporated in integrated control of the oak disease, biofumigation by itself would not be effective enough for the substantial suppression of P. cinnamomi inoculum. 相似文献
63.
Neetu Shahi László Ardó Gyöngyvér Fazekas Elen Gócza Shivendra Kumar Norbert Rèvèsz Zsuzsanna Jakabné Sándor Zsuzsanna Molnár Galina Jeney Zsigmond Jeney 《Aquaculture International》2018,26(3):727-741
To evaluate the effect of thermal and microbial stress on the immune response of common carp (Cyprinus carpio L.), relative mRNA expression level of pro-inflammatory cytokines [tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β] and other genes related to immune or stress response [inducible nitric oxide synthase (iNOS), heat shock protein 70 (Hsp70), superoxide dismutase one (SOD1), and glucocorticoid receptor (GR)] was measured by quantitative PCR (qPCR). In addition, total protein and total immunoglobulin level in blood plasma of experimental common carp was also assayed. All the above parameters were estimated 24 h post-challenge with Gram-negative bacterium, Aeromonas hydrophila. Common carp (54.89?±?6.90 g) were initially exposed to 20 °C (control group) and 30 °C (thermal stress group) water temperature for 30 days, followed by experimental challenge with 2.29?×?108 colony forming unit/mL (CFU/mL; LD50 dose) of A. hydrophila. Exposure of fish to thermal stress and subsequently challenge with A. hydrophila significantly (P?<?0.05) increases the IL-1β mRNA expression in head kidney and spleen of common carp by ~?39.94 and ~?4.11-fold, respectively. However, TNF-α mRNA expression in spleen decreased ~?5.63-fold in control fish challenged with A. hydrophila. Thermal stress and challenge with bacterium suppresses the iNOS and GR mRNA expression in spleen of common carp. Moreover, significant (P?<?0.05) increase in total protein content of blood plasma (~?43 mg/g) was evident in fish exposed to thermal stress and challenged with A. hydrophila. In conclusion, our study highlights the importance of elevated temperature stress and microbial infection in differential regulation of expression of several immunogenes in common carp. 相似文献
64.
Silvia Carolina Moreno-Rivas Concepción Lorenia Medina-Rodríguez Patricia Isabel Torres-Chávez Benjamín Ramírez-Wong Luis Carlos Platt-Lucero 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(2):148-154
The extrusion process allows the production of nixtamalized corn flour rich in arabinoxylans, which help to prevent cardiovascular and intestinal diseases. During extrusion, physiochemical properties of nixtamalized corn flour are negatively modified. The use of enzymes such as xylanase in order to obtain nixtamalized corn flour using extrusion has been studied as an alternative to reduce these changes in corn flour tortilla. The aim of this research was to evaluate changes in protein solubility of extruded nixtamalized corn flour with and without different concentrations of xylanase enzyme (0.05, 0.075, and 0.1 %, w/w). Soluble proteins of each corn flour were extracted and analyzed by SE-HPLC, while insoluble proteins were determined by the combustion method. In addition, each corn flour was analyzed by scanning electron microscopy (SEM). Results showed that the extruded nixtamalized corn flour, with and without xylanase, increased the protein solubility, and this effect was lower in extruded nixtamalized corn flour with xylanase. Insoluble protein diminished in corn flours either with or without xylanase enzyme. The addition of xylanase reduces the effect that the extrusion process has on the solubility proteins of extruded nixtamalized corn flour. 相似文献
65.
The odor-active compounds of dry-fermented sausages with added nitrite or nitrate as curing agents were identified by gas chromatography-olfactometry (GC-O) applying the detection frequency (DF) method. The quantification of these compounds in the sausage was determined by multiple headspace solid-phase microextraction (multiple HS-SPME). There were no specific odor-active compounds related to the use of nitrite or nitrate although there were differences in the DF value of several compounds. The nitrite-added sausages presented higher DF values for ethanol, 1-hexanol, propanoic acid, 2-heptenal, and nonanal while the nitrate-added sausages had higher DF values for phenylacetaldehyde and 3-methyl-butanal. Eighteen compounds were quantified by multiple HS-SPME. Most of them were above their air detection thresholds, but only hexanal, heptanal, and 1-octen-3-ol were in a concentration higher than their oil threshold values. These compounds would probably be the main contributors to the aroma of fermented sausages. 相似文献
66.
Evaluation of preflooding effects on iron extractability and phytoavailability in highly calcareous soil in containers 下载免费PDF全文
Inmaculada Sánchez‐Alcalá María del Carmen del Campillo Vidal Barrón José Torrent 《植物养料与土壤学杂志》2014,177(2):150-158
Previous pot cropping and laboratory incubation experiments were consistent with field observations showing that temporary flooding before cropping can increase the availability of soil Fe to plants. To study the effect of temporary flooding on changes in soil Fe phytoavailability we used 24 highly calcareous, Fe chlorosis–inducing soils to carry out a pot experiment where peanut and chickpea were successively grown after flooding for 30 d. At the end of the cropping experiment, the preflooded soil samples exhibited higher concentrations of acid oxalate‐, citrate/ascorbate‐ and diethylenetriaminepentacetic acid (DTPA)–extractable Fe (Feox, Feca, and FeDTPA, respectively) than the control (nonflooded) samples. Also, Feox and Feca exhibited no change by effect of reflooding of the cropped soils or three wetting–drying cycles in freeze‐dried slurries of soils previously incubated anaerobically for several weeks. Leaf chlorophyll concentration (LCC) in both peanut and chickpea was greatly increased by preflooding. The best predictor for LCC was Feox, followed by Feca and FeDTPA. The LCC–soil Fe relationships found suggest that the Fe species extracted by oxalate and citrate/ascorbate from preflooded soils were more phytoavailable than those extracted from control soils. However, the increased phytoavailability of extractable Fe forms was seemingly limited to the first crop (peanut). Flooding dramatically increased FeDTPA; however, high FeDTPA levels did not result in high LCC values, particularly in the second crop. Therefore, this test is a poor predictor of the severity of Fe chlorosis in preflooded soils. 相似文献
67.
1. Eggs from wild and captive populations of Greater Rhea (Rhea americana) were studied to determine their physical and chemical characteristics. 2. Significant differences were found among populations in almost all chemical parameters studied, whereas within physical parameters only shell weight (as a proportion of the entire egg) and density showed differences. 3. Eggs from wild populations had the highest protein and linolenic acid and the lowest total lipid contents, while cholesterol levels of these eggs and of those from the largest captive area were the lowest. 相似文献
68.
69.
J L López-Rivero E Agüera J G Monterde J Vivo M V Rodríguez-Barbudo 《American journal of veterinary research》1992,53(5):847-850
The mean area and minimal diameter of 3 histochemically determined myofiber types (1, 2A, and 2B; myosin ATPase in acid buffer) were calculated in middle gluteal muscle biopsy specimens from 62 stallions, 47 Andalusians and 15 Arabians, ranging in age from 6 to 12 years. Fourteen Andalusians and 7 Arabians were untrained, and the remainder were actively endurance-trained. The 6-month training schedules involved walking, slow trotting, and cantering. Fourteen Andalusians were moderately endurance-trained, whereas the other 19 Andalusians and 8 Arabians were strongly endurance-trained. Significant differences were not recorded between untrained and endurance-trained Arabians with respect to the area (type 1, 3,194 +/- 869 microns 2 and 3,150 +/- 370 microns 2; type 2A, 3,819 +/- 890 microns 2 and 3,380 +/- 356 microns 2; and type 2B, 4,872 +/- 962 microns 2 and 4,417 +/- 646 microns 2) or minimal diameter (type 1, 52.2 +/- 7.4 microns and 52.8 +/- 3.1 microns; type 2A, 58.1 +/- 6.7 microns and 55.0 +/- 2.8 microns; and type 2B, 65.3 +/- 6.4 microns and 63.4 +/- 4.3 microns) of the 3 fiber types, nor between untrained and endurance-trained Andalusians with respect to the area (untrained, 3,990 +/- 690 microns 2; moderately endurance-trained, 3,882 +/- 347 microns 2; and strongly endurance-trained, 3,758 +/- 510 microns 2) and minimal diameter (untrained, 58.1 +/- 4.7 microns; moderately endurance-trained, 59.7 +/- 2.7 microns; and strongly endurance-trained, 58.7 +/- 4.5 microns) of 2A fibers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
70.
Berta Caballero-López José M. Blanco-Moreno Nicolás Pérez-Hidalgo José M. Michelena-Saval Juli Pujade-Villar Emilio Guerrieri José A. Sánchez-Espigares F. Xavier Sans 《Journal of pest science》2012,85(1):81-88
The aphid–natural enemy interaction in winter wheat fields constitutes a complex system that has been frequently studied because
of its implication for biological control. However, not all of the aphids living in cereal fields are crop pests, as there
are also aphids living on weeds that may serve as alternative hosts or prey for aphid parasitoids or predators. In this context,
a concomitant survey of the plant and insect communities was conducted to understand how different plant communities affect
the abundance and richness of aphids and the interactions with their natural enemies. The plant community was split into functional
groups (grasses, legumes and forbs), and the aphid community was divided into feeding groups according to their host preferences
(specialists in grasses or forbs). The grass aphids, which dominated the total aphid catches, responded positively to grass
cover, which was particularly enhanced in the conventional fields. Conversely, the forb aphids, which mainly conditioned the
total species richness of the aphids, were closely correlated with the local abundance of legumes. The system of cereal aphid-parasitoids
was enhanced in the conventional fields, where the abundance of grasses was higher, whereas the legumes of the organic fields
indirectly played a key role in enhancing the richness of the parasitoids and the abundance of predators. Our findings indicate
that a bottom-up effect exists throughout the plant community, aphids, and aphidophagous insects and that plant community
characteristics should be considered to better understand cereal aphid control. 相似文献