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Towards the More Efficient Use of Water and Nutrients in Food Legume Cropping 全文
2000
Ali, M | Dahan, R | Mishra, J P | Saxena, N P | Knight, R
Nutrient imbalance and soil moisture stress are the major abiotic constraints limiting productivity of cool season food legumes. These constraints are more pronounced in the semi-arid tropics and sub-tropics which are the principal production zones of chickpea, lentil and faba bean. The legumes are generally grown on residual moisture as a mono crop and consequently face drought especially during the reproductive phase. In recent years, chickpea, lentil, peas and faba bean have been grown in some areas with an irrigated/assured water supply under intensive cropping to sustain cereal based systems. An increased water supply favourably influences productivity in dry environments. Faba bean, French beans and peas show a relatively better response to irrigation. The pod initiation stage is considered most critical with respect to moisture stress. Excessive moisture often has a negative effect on podding and seed yield. Eighty to ninety percent of the nitrogen requirements of leguminous crops is met from N2 fixation hence a dose of 15–25 kg N ha-1 has been recommended. However, in new cropping systems like rice-chickpea, higher doses of 30–40 kg N ha-1 are beneficial. Phosphorus deficiency is wide spread and good responses occur to 20 to 80 kg P2O5 ha-1, depending on the nutrient status of soil, cropping systems and moisture availability. Response to potassium application is localized. The use of 20–30 kg S ha-1 and some of the micronutrients such as Zn, B, Mo and Fe have improved productivity. Band placement of phosphatic fertilizers and use of bio-fertilizers has enhanced the efficiency of applied as well as native P. Foliar applications of some micronutrients have been effective in correcting deficiencies. Water use efficiency has been improved with some management practices such as changed sowing time, balanced nutrition, mulching and tillage.
显示更多 [+] 显示较少 [-]Analytical artifacts caused by the presence of water vapor in the headspace of food products 全文
2000
Canac-Arteaga, D. | Viallon, C. | Berdagué, J.L.
External corrosion of tinplate as affected by cooling-water composition in the food preserving industry
2000
Montanari, A. | Curotti, C. | Pezzani, A. | Cassara, A. | Ganassi, B. | Fortini, G. | Grischott Oppici, F. (Stazione Sperimentale per l'Industria delle Conserve Alimentari (SSICA), Parma (Italy))
External corrosion of tinplate cans containing food products, although less frequent and comparatively less dangerous than internal corrosion, should anyhow be studied more in depth, since the consumer requires not only high-quality products, but also cans having a good appearance. The objective of this experimental work was to study the influence of the main ions present in cooling waters on the corrosion of metal food cans. After a short introduction on tinplate corrosion phenomena and on the chemical and processing factors affecting it, the results are shown which were obtained from electrochemical corrosion trials performed using model solutions at various concentrations as well as cooling water samples directly taken from food plants. This research work yielded information on the corrosion mechanisms (extent and morphology) of the various species and parameters affecting the aggressivity of industrial waters (presence of additives, free chlorine content and conductivity) | La corrosione esterna delle scatole di banda stagnata contenenti prodotti alimentari, sebbene meno frequente e relativamente meno pericolosa della corrosione interna, deve comunque essere oggetto di maggiore attenzione, in quanto il consumatore richiede, oltre a prodotti di alta qualita', contenitori di aspetto accettabile. Oggetto del lavoro sperimentale e' stato lo studio dell'influenza dei principali ioni presenti nelle acque di raffreddamento sulla corrosione delle scatole metalliche per alimenti. Dopo una breve introduzione sui fenomeni di corrosione della banda stagnata e sui fattori chimici e di processo che la condizionano, il lavoro illustra i risultati ottenuti nelle prove di corrosione elettrochimiche effettuate con soluzioni modello a diverse concentrazioni e con acque di raffreddamento prelevate direttamente presso industrie alimentari. A conclusione della ricerca sono state ottenute informazioni sul meccanismo di corrosione (intensita' e morfologia) delle diverse specie e sui parametri che influenzano l'aggressivita' delle acque industriali (presenza di additivo, concentrazione di cloro libero e conducibilita')
显示更多 [+] 显示较少 [-]Estimated per capita water ingestion in the United States | Survey of food intakes by individuals 全文
2000
Effects of copper on reproduction of two collembolan species exposed through soil, food, and water 全文
2000
Pedersen, M.B. | Gestel, C.A.M. van | Elmegaard, N.
Extrapolation of laboratory toxicity data to the field is hampered by differences in bioavailability, among other factors. Often, chemical availability of substances in the soil pore water is considered equivalent to bioavailability. However, for collembolans, which are not closely connected with the water phase of the soil, the situation may be different since other routes of exposure may also be of importance. In the present study, two species of Collembola, Folsomia candida Willem and Folsomia fimetaria L., were exposed to copper sulfate in different ways, for example, in aqueous solutions, in spiked soil, in soil from a copper-contaminated field site, and via the food supply (yeast). Reproduction of the collembolans was inhibited at elevated soil or yeast copper concentrations. The 10% effective concentration (EC10) values for freshly spiked soil were 50 [0.03-13,095] and 141 [20-1,1001] mg/kg for F. candida and F. fimetaria, and the corresponding values for yeast exposure were 2,900 [613-13,877] and 361 [0.1-972,864] mg/kg (95% confidence limits in square brackets). Soil from the contaminated field site had no effects on reproduction at copper concentrations up to 2,500 mg/kg. Internal copper concentrations were constant up to a soil copper concentration between 400 and 800 mg/kg in newly spiked soil and up to between 1,400 and 2,500 mg/kg in field soil. Copper accumulation in the animals from freshly spiked soil was higher than from yeast, and accumulation from both routes appeared to be additive. Spiked soil resulted in higher accumulation than soil from a contaminated field site. Addition of clean yeast to spiked soil resulted in a decrease in copper accumulation. The two collembolan species accumulated comparable concentrations from soil, whereas F. candida accumulated more copper from contaminated yeast placed on top of unpolluted soil than F. fimetaria. Male F. fimetaria accumulated more copper from contaminated soil than females. When exposed through yeast, the two sexes accumulated similar concentrations. A link between internal copper concentrations and effects on reproduction was difficult to establish because of large variations in both parameters and because effects seemed to begin at soil and yeast copper concentrations where internal concentrations were still regulated. Consequently, the establishment of a fixed internal threshold was uncertain.
显示更多 [+] 显示较少 [-]Analytical artifacts caused by the presence of water vapor in the headspace of food products 全文
2000
Canac-Arteaga , D. (INRA (France). UR 0370 Station de Recherches sur la Viande) | Viallon , C. (INRA (France). UR 0370 Station de Recherches sur la Viande) | Berdagué , J.L. (INRA (France). UR 0370 Station de Recherches sur la Viande)
oCRF and CRF (6-33) depress food but not water intake in the obese Zucker rat
2000
Bjenning, C.A. | Rimvall, K.
It has previously been demonstrated that oCRF and the CRF binding protein inhibitor CRF (6-33) reduce body-weight gain in obese Zucker rats. We investigated whether the reduction in body-weight is attributable to altered feeding and drinking behaviour. Obese Zucker rats were fitted with osmotic mini-pumps connected to i.c.v. cannulas. Vehicle, oCRF (5 microgram/day) or CRF (6-33) (25 microgram/day) were infused for 7 days and the animals observed for an additional 7 days. Body-weight and food and water-intake were recorded daily at 14.00 h. In agreement with published results, oCRF and CRF (6-33) significantly reduced body-weight gain in the obese Zucker rat. In addition, food intake was reduced, whereas water consumption was unaffected.
显示更多 [+] 显示较少 [-]Water budget in a soil with food crops in the semi-arid region of northeast Brazil
2000
Antonio, A.C.D. | Sampaio, E.V.S.B. | Dall'Olio, A. | Salcedo, I.H.
Contamination of food and water by human pathogenic viruses | La contamination de l'eau et des aliments par les virus pathogenes pour l'homme
2000
Scipioni, A. | Daube, G. | Thiry, E. (Universite de Liege, Sart Tilman (Belgium). Faculte de medecine veterinaire)
Food and water contamination by human viruses is a great health problem. These viruses are shed in stools. Norwalk-like viruses, hepatitis E virus, poliovirus, echovirus, hepatitis A virus, rotavirus, astrovirus, enteric adenovirus and parvovirus B19 have been described. The most important ones are Norwalk-like viruses, rotavirus and hepatitis A virus as reported in epidemiological surveys. The most frequently implicated foods are shellfish (bivalve mollusks) harvested from waters contaminated with human sewage, as well as water itself. The other source of infection is the handling of food in poor hygienic conditions. In this case contaminated foods are vegetables, sandwiches, fruits, pastries that are soiled. The detection of viruses in foods is difficult for several reasons: Virusfood interactions make difficult the concentration and the purification of viruses, several virus species are difficult or unable to grow in cell culture, furthermore viruses are present in the sample in very low amounts. Molecular techniques are therefore the methods of choice for detecting these viruses, especially the polymerase chain reaction which is often described. Another possibility consists in a fecal viral indicator. Bacteriophages seem to be the most promising in this respect.
显示更多 [+] 显示较少 [-]Food and feeding habits of Siganus rivulatus and Siganus luridus from the coastal Mediterranean water off Alexandria
2000
Hamza, A-K. | Mohamed, N.I. | El-Serafy, S. (National Institute of Oceanography and Fisheries, Alexandria (Egypt))
Commercial fish landing at Abu Qir and Alanfoushy markets was the source of Siganus rivulatus and Siganus luridus sampled for food and feeding habits analysis. Food indices and food content were studies in stomach analyses of 1485 fishes
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