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991.
Cho BO Ryu HW Jin CH Choi DS Kang SY Kim DS Byun MW Jeong IY 《Journal of agricultural and food chemistry》2011,59(21):11442-11448
The aim of this study was to investigate the protective ability of blackberry extract (BE) against oxidative stress in carbon tetrachloride (CCl(4))-treated rats. The results showed that treatment with BE attenuated lipid peroxidation that was increased by CCl(4) and also markedly recovered the activity of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), that were decreased by CCl(4). BE also elevated the protein expression levels of NF-E2-related factor-2 (Nrf2), CuZnSOD, MnSOD, GPx-1/2, and heme oxygenase-1 (HO-1), but not that of catalase. Furthermore, the administration of BE significantly attenuated the levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) that were increased by CCl(4). Therefore, the present study suggests that BE possesses significant protective effects against in vivo oxidative stress. 相似文献
992.
João Gomes da Costa Edjane Vieira Pires Alessandro Riffel Michael A. Birkett Ervino Bleicher Antônio Euzébio Goulart Sant’Ana 《Euphytica》2011,177(3):299-307
The aim of this study was to demonstrate that Capsicum spp. cultivars are differentially preferred by the cotton aphid, Aphis gossypii, and to investigate the role of volatile semiochemicals in conferring differences in host preferences. Two preference assays
were conducted in 2008 under greenhouse conditions. Fourteen different commercially available cultivars were grown in cages
protected by an anti-aphid net, and were infested 60 days after planting, through the release of ten adult female A. gossypii per plant. The results showed that after a five-day infestation period, statistically significant differences in the mean
number of A. gossypii between cultivars were observed, with Sweet Pepper Hybrid Green Belt (SPHGB) being one of the cultivars with the lowest number
of A. gossypii per plant. To test the hypothesis that the preference of cultivars was associated with release of volatile, Capsicum spp-derived semiochemicals, olfactometer behavior bioassays were conducted with A. gossypii, using volatile organic compounds (VOCs) collected from non-preferred SPHGB and preferred SPAB cultivars. A. gossypii was significantly repelled only by the VOCs of infested SPHGB. Furthermore, coupled gas chromatography-mass spectrometry
(GC-MS) analysis of VOCs released by plants prior to, and after, A. gossypii infestation, revealed that the non-preferred SPHGB cultivar released nine additional compounds after infestation, including
6-methyl-5-hepten-2-one, a known plant defense semiochemical involved in plant—aphid interactions. These data suggest that
non-preferred cultivars releasing this semiochemical have the potential to be used in breeding programs aimed at producing
A. gossypii-resistant Capsicum spp. cultivars. 相似文献
993.
Ruibal-Mendieta NL Rozenberg R Delacroix DL Petitjean G Dekeyser A Baccelli C Marques C Delzenne NM Meurens M Habib-Jiwan JL Quetin-Leclercq J 《Journal of agricultural and food chemistry》2004,52(15):4802-4807
From a nutritional point of view, cereal lipids include valuable molecules, such as essential fatty acids, phytosterols, and fat-soluble vitamins. Spelt (Triticum spelta L.) is an alternative hulled bread cereal mostly grown in Belgium, where it is mainly intended for animal feed but should increasingly be used for human consumption. The present research focused on phytosterol quantification by LC/APCI-MS2 in saponified wholemeal extracts of 16 dehulled spelt and 5 winter wheat (Triticum aestivum L.) varieties grown in Belgium during 2001-2002 at the same location. Glycosylated sterols and free and formerly esterified sterols could be determined in saponified extracts. Results show that the mean phytosterol content is comparable in both cereals (whereas other lipids, such as oleic and linoleic acids, are increased in spelt wholemeal): spelt extract has, on average, 527.7 microg of free and esterified sterols g(-1) of wholemeal and 123.8 microg of glycosylated sterols g(-1) of wholemeal versus 528.5 and 112.6 microg x g(-1) in winter wheat (values not corrected for recoveries). This is the first report on the application and validation of an LC/MS2 method for the quantification of phytosterols in spelt and winter wheat. 相似文献
994.
Thirty-four plant essential oils were screened for their acaricidal and oviposition deterrent activities against two-spotted
spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae), in the laboratory using a leaf-dip bioassay. From initial trials, sandalwood and common thyme
oils were observed to be the most effective against TSSM adult females. Subsequent trials confirmed that only sandalwood oil
was significantly active (87.2 ± 2.9% mortality) against TSSM adult females. Sandalwood oil also demonstrated oviposition
deterring effects based on a 89.3% reduction of the total number of eggs on leaf disks treated with the oil. GC–MS analysis
revealed that the main components of the sandalwood oil were α-santalol (45.8%), β-santalol (20.6%), β-sinensal (9.4%), and epi-β-santalol (3.3%). A mixture of α- and β-santalol (51.0:22.9, respectively) produced significantly higher mortality (85.5 ± 2.9%) and oviposition deterrent effects
(94.7% reduction in the number of eggs) than the control. Phytotoxicity was not shown on rose shoots to which a 0.1% solution
of sandalwood oil was applied. 相似文献
995.
Antoniassi NA Boabaid FM Souza RL Nakazato L Pimentel MF Filho JO Pescador CA Driemeier D Colodel EM 《Journal of zoo and wildlife medicine》2011,42(1):118-120
This report describes toxoplasmosis infection in a black-headed night monkey (Aotus nigriceps) from the Zoological Park of the Federal University of Mato Grosso, Brazil. The animal was submitted alive to the Veterinary Hospital of the Federal University of Mato Grosso presenting neurologic clinical signs. There were no improvements on the animal's clinical condition after treatment, so it was euthanized. At necropsy, the most significant gross lesions observed were hemorrhages diffusely scattered throughout the cerebral hemispheres. Histologic findings were characterized by nonsuppurative encephalitis and mild multifocal necrotizing nonsuppurative myocarditis. Groups of tachyzoites and cysts were observed surrounding the inflamed areas of cerebral parenchyma. Sections of the brain were submitted for immunohistochemistry examination for Toxoplasma gondii and Neospora caninum and also for polymerase chain reaction (PCR) to determine the presence of Toxoplasma gondii. The samples were positive for Toxoplasma gondii by PCR; however, cross reactivity was observed between Toxoplasma gondii and Neospora caninum antibodies. These findings were consistent with a toxoplasmosis infection in this animal. 相似文献
996.
Sevá Ada P Sercundes MK Martins J de Souza SO da Cruz JB Lisboa CS Correa SH Soares RM 《Journal of zoo and wildlife medicine》2011,42(2):326-329
The present study aimed to determine whether Cryptosporidium oocysts were present in stools from captive snakes at Funda??o Parque Zoológico (Zoological Park Foundation) in S?o Paulo, Brazil. Two collections were performed; the first in July 2008 and the second in February 2009. Fecal samples were collected from 74 enclosures that housed 101 individuals of 23 snake species. The stool specimens collected from 16 out of the 74 enclosures (21.6%) contained Cryptosporidium spp. oocysts; all of them were confirmed as Cryptosporidium serpentis, using molecular techniques. Only in three (18.7%) out of the 16 enclosures with positive samples were there animals with clinical signs compatible with infection by C. serpentis, such as regurgitation and significant progressive weight loss. From the results, it was concluded that diagnostic examinations need to be performed periodically, even on clinically healthy animals, as a preventive measure. 相似文献
997.
Federally funded range improvement treatments in the United States require that land managers consider the treatment’s impacts to archaeological sites. Pending archaeological clearance can result in the postponement or exclusion of effective seeding practices, which in turn can result in poor seed establishment, increased weeds, recurrent fire, accelerated soil erosion, and damage to cultural sites. Less intensive requirements would help relieve time restrictions, but less-conspicuous sites might be missed. We quantified the displacement and damage that lithic artifacts would incur if missed in an inventory and subsequently subjected to drill seeding treatments. We subjected chert, quartzite, and obsidian materials to impact by a rangeland drill and a no-till drill on sandy and silty soils. Soil texture was the most important factor in perpendicular lithic movement. In the silty soil, lithics were displaced perpendicular to the direction of the drill nearly twice as far as in the sandy soil (7.8 cm ± 0.9 SE vs. 4.1 cm ± 0.6 SE, P < 0.01). No experimental factor showed a difference in absolute displacement (mean = 15 cm). Damage to lithics was infrequent (25%) and minor with no experimental factor showing statistical significance. Approximately 30% of lithics were buried by treatments. In the sandy soil, the rangeland drill buried lithics 6.5 mm ± 1.6 SE deep, on average, which was twice as deep as the no-till drill in the sandy soil (3.0 mm ± 0.9 SE) and four times as deep as both drills in the silty soil (1.5 mm ± 0.5 SE; P = 0.03). Minimal effects of drill seeding on lithics suggest that drill seeding could proceed with less-intensive archaeological surveys. 相似文献
998.
Jae Yeol YoonJi San Shin Dong Young ShinKyu Hwan Hyun Nilda R. BurgosSungbeom Lee Yong In Kuk 《Pesticide biochemistry and physiology》2011,99(1):65-76
Paraquat is labeled for row-middle application on cucurbits, but drift to crop foliage is inevitable. Experiments were conducted to determine whether differential tolerance to paraquat existed among leaves of various ages in Cucurbita spp. (squash) and other plants, and to examine whether leaves tolerant to paraquat are also tolerant to other herbicides and abiotic stresses. Physiological responses to paraquat, including antioxidant activity, were investigated in squash leaves to identify mechanisms of paraquat tolerance. Although the level of paraquat tolerance differed by leaf age, cultivar, and species, the level of paraquat injury was lower in younger leaves than in older leaves in 14 of 18 squash cultivars and 5 of 12 other species tested. Cellular leakage and lipid peroxidation were consistently lower in the youngest leaf (leaf 4) than in the older leaves. Quantum yield and relative chlorophyll content were the same in all leaves of nontreated plants. Epicuticular wax content was higher in the youngest leaf than in leaves 1, 2, and 3 of cv. ‘Joongangaehobak’ and ‘Wonbiaehobak’. However, leaf cuticle content was not consistent with leaf ages. Differential leaf response to paraquat was partially correlated with the change in catalase, peroxidase, ascorbate peroxidase (APX), and glutathione reductase activities in nontreated and treated leaves. The APX activity in the youngest leaf was generally 2 times higher than in leaves 1-3 in both nontreated and treated plants. Ascorbate antioxidant levels were also higher in the youngest leaf than those in leaves 1-3. Leaves tolerant to paraquat were also tolerant to diquat and to abiotic stresses, low temperature and drought. However, tolerance to oxyfluorfen, which has a different mode of action than paraquat and diquat, was higher in older than in younger leaves. Higher tolerance to paraquat-mediated oxidative and abiotic stresses in young leaves of most squash cultivars might contribute to the differential prevention of oxidative damage in leaves of various ages. 相似文献
999.
Maluta Nathalie Kristine Prado Lopes João Roberto Spotti Fiallo-Olivé Elvira Navas-Castillo Jesús Lourenção André Luiz 《Journal of pest science》2021,94(4):1265-1276
Journal of Pest Science - The whiteflies of the Bemisia tabaci (Genn.) complex (Hemiptera: Aleyrodidae) are serious agricultural pests that cause severe losses to vegetable, ornamental and fiber... 相似文献
1000.
Zhang Chenglong Valente João Kooistra Lammert Guo Leifeng Wang Wensheng 《Precision Agriculture》2021,22(6):2007-2052
Precision Agriculture - Advances in sensor miniaturization are increasing the global popularity of unmanned aerial vehicle (UAV)-based remote sensing applications in many domains of agriculture.... 相似文献