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71.
Luis Miguel Brito Áurea Sampaio Rui Pinto Isabel Mourão João Coutinho 《Journal of plant nutrition》2016,39(6):842-849
The response of lettuce to production system, organic and phosphate fertilizers and root mycorrhization, was evaluated in two pot trials with factorial treatment combination of: (i) soil type (from organic and from conventional production systems) and organic fertilizer (0, 2 and 4 t ha?1) in the first trial; and (ii) mycorrhizal inoculation (mycorrhized and non-mycorrhized plants) and Gafsa phosphate (0, 100 and 200 kg P2O5 ha?1) in the second. Lettuce growth decreased with increasing rates of the organic fertilizer because of its very high electrical conductivity (50.1 dS m?1) and lack of maturation. However, the fertilizer harmful effects were minimized in the soil from organic production. The application of Gafsa phosphate significantly increased lettuce yield and nutrient uptake. However, for the highest rate of phosphate, mycorrhized lettuce yield decreased compared to non-mycorrhized lettuce, suggesting that high soil available P may have harmful effects on the activity of mycorrhizal fungi. 相似文献
72.
Miguel Esquivel Leonor Castiñeiras Bartolomé Rodríguez Karl Hammer 《Genetic Resources and Crop Evolution》1987,35(2):367-378
Summary After a short introduction into recent collecting activities in Cuba information is provided concerning the joint expedition of the Instituto de Investigaciones Fundamentales en Agricultura Tropical and the Zentralinstitut für Genetik und Kulturpflanzenforschung in the province of Holguín, Eastern Cuba, in February 1986 within the agreement between the Academy of Sciences of Cuba and the Academy of Sciences of the German Democratic Republic. Altogether 249 accessions of vegetables, pulses, cereals and other crops were collected. A remarkable diversity was found inCapsicum andPhaseolus. The material collected is important for breeding purposes.
Sammlung pflanzlicher genetischer Ressourcen in Kuba
Zusammenfassung Nach einer kurzen Einführung in die Sammelarbeit der letzten Jahre in Kuba folgen Informationen über die gemeinsame Expedition des Instituto de Investigaciones Fundamentales en Agricultura Tropical und des Zentralinstituts für Genetik und Kulturpflanzenforschung, die im Rahmen des Abkommens zwischen der Akademie der Wissenschaften Kubas und der Akademie der Wissenschaften der Deutschen Demokratischen Republik im Februar 1986 durchgeführt wurde und in die Provinz Holguín, Ost-Kuba, führte. Insegsamt wurden 249 Proben von Gemüsen, Hülsenfrüchten, Getreiden und anderen Fruchtarten gesammelt. Eine bemerkenswerte Variation wurde beiCapsicum andPhaseolus gefunden. Das Sammelmaterial ist für Züchtungszwecke von Bedeutung.
¶rt; , , , ¶rt; . C 1986 . . 249 , , . Capsicum Phaseolus. .相似文献
73.
Improvement of table grapes quality and safety by the combination of modified atmosphere packaging (MAP) and eugenol, menthol, or thymol 总被引:1,自引:0,他引:1
Valverde JM Guillén F Martínez-Romero D Castillo S Serrano M Valero D 《Journal of agricultural and food chemistry》2005,53(19):7458-7464
Table grape is a nonclimacteric fruit that shows a rapid loss of quality during storage and is very susceptible to colonization by fungi, especially Botrytis cinerea, which is considered the most important disease of this commodity. To solve this problem, synthetic fungicides have been used, although legal restrictions and consumer's concern demand the search of other safe means. In the present paper, and as an alternative of synthetic fungicides, an active packaging to improve MAP effectiveness on preserving table grape (cv. Crimson Seedless) quality and safety was developed by the addition of 0.5 mL of eugenol, thymol, or menthol inside the packages. Packages were stored at 1 degree C for 35 days. The final gas composition inside the packages was 1.4-2.0 and 10.0-14.5 kPa of CO(2) and O(2), respectively, with no significant slight differences among treatments. Results showed that the addition of eugenol, thymol, or menthol improved the beneficial effect of MAP in terms of delaying weight loss and color changes, retarding degrees Brix/acidity ratio evolution, and maintaining of firmness. Thereafter, these treatments showed additional benefit in terms of delayed rates of rachis deterioration and berry decay. Finally, the total viable counts for both mesophilic aerobics and especially yeast and molds were significantly reduced in the grapes packaged with the natural antimicrobial compounds. All of the above effects led to maintenance of table grape quality and safety for longer storage periods (3 additional weeks as compared to controls under MAP only). 相似文献
74.
Chemical composition and antifungal activity of essential oil of Chrysactinia mexicana gray 总被引:1,自引:0,他引:1
Cárdenas-Ortega NC Zavala-Sánchez MA Aguirre-Rivera JR Pérez-González C Pérez-Gutiérrez S 《Journal of agricultural and food chemistry》2005,53(11):4347-4349
The chemical composition of the essential oil of Chysactinia mexicana was analyzed by gas chromatography-mass spectrometry. Seventeen compounds were characterized; eucalyptol (41.3%), piperitone (37.7%), and linalyl acetate (9.1%) were found as the major components. The essential oil of leaves and piperitone completely inhibited Aspergillus flavus growth at relatively low concentrations (1.25 and 0.6 mg/mL, respectively). 相似文献
75.
María Delclaux Covadonga Talavera Manuel López Jose Miguel Sánchez María Isabel García 《Journal of zoo and wildlife medicine》2002,33(3):283-285
A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr. 相似文献
76.
B.Miguel Osorno Carlos Vega Miodrag Ristic Carlos Robles Samuel Ibarra 《Veterinary parasitology》1976,2(1):111-120
Babesiosis is a worldwide tick-borne protozoan disease of a variety of wild and domestic animals. For decades, various babesia strains were considered host-specific. However, babesiosis has been diagnosed as the cause of acute illness in 13 human beings in recent years, three of whom died. Studies of babesiosis in domestic animals indicate that for every clinically demonstrable case, there are hundreds of cases of latent infection. In an effort to determine if human babesia infections might be present in Mexico, we selected as our testing ground an endemic rural area along the Gulf Coast where continuous epizootics of equine, bovine, ovine and canine babesiosis were known to occur. Of the 101 individuals examined serologically by the indirect hemagglutination (IHA) test using Babesia canis as antigen, 38 reacted at titers from 1 : 10 to 1 : 80. Blood from these reactors was injected into splenectomized hamsters. Hamsters inoculated with blood from three of the individuals showed babesia in their peripheral blood. The growth of the organism was established by subpassages into additional hamsters. The persons from whom the organisms were isolated were asymptomatic for babesiosis. None of the 29 individuals residing in Mexico City, which represented the urban population in the survey, reacted in the IHA test. This is the first documented finding of the latent form of human babesiosis. 相似文献
77.
Joseph B. Goodwin Fernando L. Garagorry Waldo Espinosa Luis Marcelo Sans Leif J. Youngdahl 《Agricultural Systems》1982,8(2):115-127
A soil-water balance simulation model developed for the Cerrado soils of central Brazil is presented. The model calculates daily soil water evaporation, plant transpiration and soil-water balance for fourteen soil layers of 15 mm each. The model includes a subroutine to calculate capillary water movement. Computer simulations of daily soil water levels at five soil depths (15, 30, 45, 60 and 90 cm) for a field of maize are compared with actual field measurements over an 80-day period. Results indicated that the developed model can, in general, estimate the soil-water balance of the various depths within ± 10% of actual measurements. 相似文献
78.
79.
80.
Miguel Salgado Elizabeth J B Manning Michael T Collins 《Journal of veterinary diagnostic investigation》2005,17(4):350-354
Antibody detection-based tests for paratuberculosis offer speed and economy, 2 diagnostic test attributes important to animal industries with narrow profit margins. Application of such tests to individual milk samples instead of serum samples can further improve testing efficiency and decrease testing cost. Accuracy of a commercial bovine paratuberculosis enzyme-linked immunosorbent assay (ELISA) adapted for use on goat serum and milk samples was determined. Fecal, blood, and milk samples were collected from 159 goats belonging to 2 Wisconsin goat herds with a prior history of paratuberculosis and 1 herd of 50 goats from a paratuberculosis-free Wisconsin herd. Fecal samples were cultured using the modified BACTEC 12B media. Sera were tested according to the manufacturer's instructions for bovine samples. Milk samples were centrifuged and mixed with the ELISA kit's Mycobacterium phlei-containing diluent at a ratio of 1:2. Using fecal culture as the "gold standard," the sensitivity of the ELISA on goat serum was 64% and the sensitivity of the ELISA on goat milk was 48%. The milk ELISA had higher agreement with fecal culture results (kappa = 0.525) than the serum ELISA (kappa = 0.425). ELISA specificity was 100% on both serum and milk. Regression analysis also showed good correlation between serum and milk S/P values (r2 = 0.67). Although less sensitive, the ELISA on goat milk samples appears to offer a useful, low-cost alternative for detection of goats with paratuberculosis that have progressed to the stage of shedding M. paratuberculosis in their feces. 相似文献