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641.
Two new phenolic esters 9-trans-p-coumaroyloxy-alpha-terpineol (1) and 7-trans-p-coumaroyloxy-taedol (2), both endowed with free radical scavenger activity and cleroda-3,13 (E)-dien-15,18-diol (3) for which a cis stereochemistry at the decalin junction was found, were isolated from the resinous exudate from Haplopappus taeda upper parts. 相似文献
642.
Fishing down marine food webs 总被引:20,自引:0,他引:20
D Pauly V Christensen J Dalsgaard R Froese F Torres 《Science (New York, N.Y.)》1998,279(5352):860-863
The mean trophic level of the species groups reported in Food and Agricultural Organization global fisheries statistics declined from 1950 to 1994. This reflects a gradual transition in landings from long-lived, high trophic level, piscivorous bottom fish toward short-lived, low trophic level invertebrates and planktivorous pelagic fish. This effect, also found to be occurring in inland fisheries, is most pronounced in the Northern Hemisphere. Fishing down food webs (that is, at lower trophic levels) leads at first to increasing catches, then to a phase transition associated with stagnating or declining catches. These results indicate that present exploitation patterns are unsustainable. 相似文献
643.
H J Van Kruiningen V P Castellano A Torres R L Sharpee 《Journal of veterinary diagnostic investigation》1991,3(4):293-296
Acute and convalescent sera were collected from 8 dairy herds with classic clinical features of winter dysentery. An enzyme-linked immunosorbent assay was used to measure coronavirus antibody titers, employing calf diarrhea coronavirus as antigen. Twenty-two of the 35 animals tested (63%) showed a greater than or equal to 4-fold seroconversion. Adult cattle in all 8 herds seroconverted. These findings complement previously reported immunoperoxidase and electron microscopic evidence, suggesting an etiologic role for an enteric coronavirus in this disease. 相似文献
644.
Rosario Torres Carla Nunes José María García Maribel Abadias Inmaculada Viñas Teresa Manso Manuel Olmo Josep Usall 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):73-83
We determined the potential of using a formulated product based on Pantoea agglomerans CPA-2, either alone or in combination with heated sodium bicarbonate (SBC) solutions, to control the major postharvest diseases
affecting citrus crops in the Mediterranean region. Treatments applied either individually or in combination were tested in
semi-commercial and commercial trials carried out with oranges and mandarins from the Algarve, Andalusia and Catalonia. Firstly,
several formulations of the biocontrol agents were tested in laboratory trials; one of them, a freeze-dried formulation of
P. agglomerans strain CPA-2 called FD10-3, was chosen for combined with SBC. This formulation, applied at 2 × 108cfu ml−1 and the SBC treatment, applied at 3% 50°C for 20–40 s, demonstrated that it was possible to reduce decay development in laboratory
trials. Semi-commercial applications of FD10-3 and 3% SBC solution at 50°C for 40 s showed excellent control of decay in unwounded
mandarins and oranges artificially inoculated with both Penicillium digitatum and P. italicum. No rind injuries or residues attributable to hot water or SBC were observed on treated fruits. Combined treatment provided
better control than the two treatments applied separately. Commercial trials demonstrated an important reduction in natural
decay with the treatment of SBC 3% at 50°C for 40 s. Furthermore, bacterial-product formulation treatment significantly reduced
the percentage of infected fruit and in some cases this reduction was equal to chemical treatments. Even so, no improvement
in efficacy was observed with the combination of FD10-3 and SBC in the commercial test. We also assessed the ability of FD10-3
to grow at the wound site in oranges, whether alone or in the presence of SBC, and also its compatibility with standard citrus
packinghouse practices. 相似文献
645.
Locating quantitative trait loci associated with Orobanche crenata resistance in pea 总被引:1,自引:1,他引:1
M R Valderrama B Román Z Satovic† D Rubiales‡ J I Cubero§ & A M Torres 《Weed Research》2004,44(4):323-328
Orobanche crenata (broomrape) is a root parasite that represents the major constraint for pea (Pisum sativum) cultivation in the Mediterranean area and the Middle East. The efficacy of available control methods is minimal and breeding for O. crenata resistance is considered the most promising strategy of control. Only moderate levels of incomplete resistance are available in pea germplasm. In order to identify and map the quantitative trait loci (QTL) controlling the trait, 115 F2 plants derived from the cross between a susceptible and a resistant parent were analysed using isozymes, random amplified polymorphic DNA and sequence tagged site markers. F2‐derived F3 lines were studied for O. crenata resistance under field conditions. The linkage map was constructed with MAPMAKER V2.0. Of 217 markers, 120 could be mapped into 21 linkage groups. Linkage groups consisted of 13 to two marker loci covering 1770 cM. The mean inter‐marker distance was 17.64 cM. Simple interval mapping (SIM) and composite interval mapping (CIM) were performed using QTL Cartographer. The CIM approach using five cofactors was clearly the most efficient way to locate putative QTL. Two QTL for O. crenata resistance (Ocp1 and Ocp2), explaining only a moderate portion of the observed variation (9.6% and 11.4% respectively), were detected. 相似文献
646.
647.
Short‐term suppression of Aedes aegypti using genetic control does not facilitate Aedes albopictus
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648.
José Rogelio Ramos-Enríquez Benjamín Ramírez-Wong Rosario Maribel Robles-Sánchez Ramón Enrique Robles-Zepeda Gustavo Adolfo González-Aguilar Roberto Gutiérrez-Dorado 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):228-234
The extrusion process (EP) consists of heat and mechanical treatments under different conditions of moisture, shear, and pressure and rapidly causes structural alterations and changes in the functional properties of the extruded material. The aim of this study was to evaluate the effect of extrusion conditions and optimize the wheat bran extrusion conditions to achieve the greatest content of phenolic compounds and antioxidant activity using response surface methodology. The EP factors evaluated were feed moisture (FM) (25–33.54%) and final extrusion temperature (T) (140–180 °C). The properties evaluated in the extruded material were bound total phenol content (BTPC), total phenolic compounds and antioxidant activity (AOX). Analysis of variance (ANOVA) and response surface methodology were used in the evaluation. The determination coefficients, (FM)2 and (T)2, very significantly affected the BTPC and bound 2,2-diphenyl-1-picrylhydrazyl content (BDPPHC). The optimization was performed by overlaying two contour plots to predict the best combination regions. The optimized extrusion conditions were the following: FM?=?30% and T?=?140 °C, which provided BTPC?=?3547.01 μgGAE/g (predicted: 3589.3 μgGAE/g) and BDPPHC?=?9.5 μmolTE/g (predicted: 10.4 μmolTE/g); and FM?=?30% and T?=?180 °C, which provided BTPC?=?3342.3 μgGAE/g (predicted: 3727.7 μgGAE/g) and BDPPHC?=?9.5 μmolTE/g (predicted: 9.3 μmolTE/g). The EP increased the phenolic compounds and AOX, and enhancement of these properties in wheat bran products could make them functional foods. 相似文献
649.
The false carmine cochineal outbreak in the semiarid region of Brazil has caused considerable damage to the cactus production for the last 16 years. Native of Mexico, the false carmine cochineal, Dactylopius opuntiae (Cockerell), has invaded other countries including recent citations in Morocco and Israel. In some countries, intentional introduction of the false carmine cochineal has been done for biological control of noxious cactus weeds; while, in Brazil, its introduction was apparently for carmine dye production. However, there was a rapid distribution through the semiarid region causing a huge problem for cactus pear production as fodder. The pest problem in Brazil has motivated studies on control alternatives. Farmers have the option to manage this pest with host-plant-resistance or alternative and synthetic insecticides. In addition, knowledge on indigenous predatory insect species with the potential to help suppressing the pest population have been generated, especially the lady beetles Zagreus bimaculosus (Mulsant), Prodiloides bipunctata Weise. Farmers should also be aware of the risks involved in transporting contaminated vegetative material and animals into pest free areas. All these practices can be fully achieved once growers start changing their current practice of cactus growing. It is particularly important for growers to conduct regular inspections in the fields to detect early infestation of the pest. Dealing with small and spatially localized infestations have been proved easier than work on highly infested areas. Cactus can still be a profitable activity if these recommendations are taken seriously. 相似文献
650.
Eduardo Moreira Barros Christian Sherley Araújo da Silva-Torres Jorge Braz Torres Guilherme Gomes Rolim 《Phytoparasitica》2018,46(3):391-404
The cotton ecosystem comprises various arthropod pest and natural enemies with simultaneous occurrence irrespective of growing region. The use of insecticides with reduced impact on natural enemies is a major goal to conserve them and, therefore, to reduce populations of arthropod pests. The survival of twelve key natural enemies for cotton pest management exposed to dried residues using the highest and lowest recommended rates representing old and new insecticides recommended to control cotton pests (chlorantraniliprole, chlofernapyr, spinosad, lambda-cyhalotrin, methidathion, pymetrozine, and thiamethoxam) was determined. The study included parasitoids [Aphelinus gossypii Timberlake, Bracon vulgaris Ashmead, Lysiphlebus testaceipes (Cresson), Telenomus podisi (Ashmead), Trichogramma pretiosum (Riley)] and predators [Hippodamia convergens Guérin-Méneville, Euborellia annulipes (Lucas), Podisus nigrispinus (Dallas), Solenopsis invicta Buren), Orius insidiosus (Say), Chrysoperla externa Hagen and Eriopis connexa (Germar)], with two different cohorts for these last two species. All natural enemies exposed to methidathion exhibited 100% mortality. Thiamethoxam, lambda-cyhalothrin and chlorfenapyr also caused high mortality of P. nigrispinus, S. invicta, H. convergens, O. insidiosus and all tested parasitoids. Among the natural enemies, E. annulipes exhibited high survival when exposed to all tested insecticides, except methidathion. Chlorantraniliprole and pymetrozine caused overall lower impact on the natural enemies tested followed by spinosad; hence, they are options for cotton pest management. Furthermore, the outcomes highlight the implication of knowing the background susceptibility of the species tested when addressing the impact of insecticides on natural enemies. 相似文献