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Jordi Marsal Jaume Casadesus Gerardo Lopez Merce Mata Joaquim Bellvert Joan Girona 《Irrigation Science》2016,34(3):201-208
The level of irrigation restriction to apply in a deficit irrigation (DI) programme for sustainable peach (‘Baby gold 6’) production was investigated. The experiment involved four irrigation treatments over five consecutive seasons (2007–2011). They were full irrigation (control), reducing irrigation by 20 % during the first half of stage III (DI-80 %), withholding irrigation until reaching a light stress level (DI-L) and withholding irrigation until reaching a moderate stress level (DI-M). The withholding of irrigation in both DI-L and DI-M was applied only during stage II and postharvest periods and was based on midday stem water potential thresholds (Ψ stem). For the DI-L treatment ?1.5 MPa was used in both periods, and for DI-M ?1.8 and ?2.0 MPa were used during stage II and postharvest, respectively. Average Ψ stem values during DI periods were approximately ?1.4 and ?1.2 MPa for DI-M and DI-L, respectively. The pre-defined thresholds required to trigger irrigation were rarely reached. No significant differences between treatments were found in terms of yield in any experimental year. However, DI-M and to a lesser extent DI-L had lower final fruit fresh mass at harvest related to lower Ψ stem after three consecutive years of the experiment (during 2010 and 2011). Therefore, in terms of fruit size, DI was not sustainable. Rather than lowering Ψ stem thresholds, we recommend discontinuing DI after 3-year application. 相似文献
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Carrilho EN Gonzalez MH Nogueira AR Cruz GM Nóbrega JA 《Journal of agricultural and food chemistry》2002,50(15):4164-4168
A single microwave-assisted acid-decomposition procedure is proposed for sample preparation of plant- and bovine-derived materials prior to multielement determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The procedure involved sample grinding in a cryogenic mill to reduce particle sizes and increase the surface area for acid attack, followed by decomposition under high pressure and temperature. A single heating program was employed and efficiently destroyed most of the organic matrix by using small volumes of nitric acid and hydrogen peroxide. Accuracy of the elemental analysis was indicated by the good agreement between certified and found values of elements in plant and animal samples at 95% confidence level. The sample preparation procedure was fast and reproducible, and proved to be efficient for elemental analysis in agricultural and food-related samples by a sensitive multielement technique such as ICP-OES. 相似文献
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Erika M. Plisetskaya Elena Fabbri Thomas W. Moon Joaquim Gutiérrez Celestina Ottolenghi 《Fish physiology and biochemistry》1993,11(1-6):401-409
The questions addressed in this study were: 1) whether insulin added to the incubation medium can down-regulate 125I insulin binding to isolated hepatocytes of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss); 2) whether quantitative assessment of insulin processing can be made on isolated fish liver cells; 3) how ambient temperatures
can affect insulin binding, and down-regulation of insulin receptors.
After isolation and a short (up to 4h) “metabolic recovery period”, liver cells were used either directly in 125I insulin binding assay or first preincubated for 18h at 4°C or for 3h at 15°C, with or without mammalian or salmon insulin
in concentrations ranging from 1 to 1000 nM.
Preincubation at 15°C, decreased binding capacity (number of binding sites per liver cell) in all five independent hepatocyte
preparations treated with 1000 nM insulin and in four out of five preparations treated with 100 nM insulin. At 4°C insulin
binding sites were down-regulated in less than 50% of all hepatocyte preparations and only in the presence of 1000 nM insulin.
Differential quantitive assessment was made of a) intact free insulin; b) insulin degraded; c) intact insulin bound to the
cell membrane; d) internalized but degraded insulin, and e) intact insulin internalized by liver cells. Hepatocytes preincubated
with 100 – 1000 nM insulin at 15°C bound and internalized less 125I insulin.
We hypothesize that in vivo, at water temperatures of 15°C and higher, extreme physiological levels of plasma insulin may regulate the numbers of insulin
receptors in the salmonid liver. In contrast, in fish inhabiting cold waters the regulation of insulin receptors by circulating
plasma insulin seems to be of little physiological importance.
Presented in part at the Western Regional Conference on Comparative Endrocrinology, Tempe, Arizona, U.S.A., 1991 and at the
Meeting of Italian Society of Experimental Biology, Sorrento, Italy, 1991. Supported by grants from NSF of the USA#DCB 8915935
to E.M.P., NSERC of Canada OPGA 6944 to T.W.M., North Atlantic Treaty Organization (NATO) grant #0926/87 to C.O. and E.M.P.,
and CYCIT grant of Spain to J.G. 相似文献
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Sara Margarida Mendes Joaquim Santos Helena Freitas José Paulo Sousa 《Agroforestry Systems》2011,82(2):139-148
Cork oak “Montados” are a particular Mediterranean ecosystem, which can be found in Southern Portugal. Portuguese “Montados”
are man-made ecosystems, mainly used for cork production and cattle farming, that support a high biological diversity. Current
sustainable management techniques imply a shrub clearing with heavy machinery, which can be highly disruptive for soil biota.
In order to evaluate the effects of understory vegetation management on soil epigeic macrofauna, five zones were defined along
a chronosequence of shrub clearing: a non-disturbed zone (zone 5) and zones where understory vegetation was cut at 4–5 years
(zone 4), at 3–4 years (zone 3), at 2 years (zone 2) and at 1 year (zone 1). A sixth zone (zone 6) was selected in a pasture,
where cattle are occasionally present. Soil fauna was sampled using “pitfall” traps and sampling took place in autumn 2003.
A total of 2,677 individuals, separated into 152 species and morphospecies, were caught in the traps. With the exception of
zone 6, that presented a lower number of species, all the other zones from the chronosequence presented, in most cases, a
similar number of taxa, species diversity (Shannon) and species richness (Margalef). Multivariate analysis separated recently
disturbed zones (plus zone 6) from those intervened at longer time; groups like Formicidae, Scydmaenidae, most families from
Araneae and insect larvae appeared closely associated to zones 3–5 (with a higher shrub cover and thick litter layers), whereas,
other Hymenoptera, Gastropda and most Coleoptera families, appeared associated to recently disturbed zones (zones 1 and 2)
and to zone 6, characterized by a lower shrub cover and a lower accumulation of litter. This separation indicates that effects
of the intervention can endure for 2 or 3 years. After that time, the normal natural regeneration of the understory vegetation
seems to support the restoration of the macrofauna community, thus indicating that the sustainable management strategy adopted,
i.e., making a shrub cut every 5–6 years, seems not induce a significant effect on local species richness of soil epigeic
macrofauna. 相似文献
49.
Saco Y Fraile L Giménez M Alegre A López-Jimenez R Cortey M Segalés J Bassols A 《Research in veterinary science》2011,91(1):52-67
The purpose of this study was to investigate the relationship between the existence of lung lesions in pigs at slaughter and the concentration of the serum acute phase proteins (APP), haptoglobin (Hp), pig-major acute protein (Pig-MAP) and C-reactive protein (CRP). A total of 24 pig farms were selected out of a larger farm database previously screened to study risk factors associated with pleuritis and cranio-ventral pulmonary consolidation (CVPC) lesions at slaughter-aged pigs in Spain. The farms were classified as “pleuritis negative (P−) or positive (P+)” and as “CVPC negative (M−) or positive (M+)” and divided into four groups according to a 2X2 factorial design (P−M−, P−M+, P+M−, P+M+). Also at slaughter, blood from 20 randomly selected pigs from each farm was collected. Obtained serum samples were used to measure acute phase proteins. All APP concentrations were significantly higher for M+ farms than for M− ones. However, only Hp and Pig-MAP showed significantly higher concentrations for P+ farms than for P− ones. Pig-MAP was the most sensitive biomarker since it was able to clearly discriminate between P−/P+ and M−/M+ groups (p < 0.001 in both cases). Hp was an excellent marker for pleuritis and good for CVPC lesions. CRP was able to discriminate for CVPC lesions but not for pleuritis. The present results indicate that Pig-MAP and, possibly Hp, may be used as potential markers to characterise and discriminate respiratory lesions in swine herds at slaughter. 相似文献
50.
de la Rue ML Takano K Brochado JF Costa CV Soares AG Yamano K Yagi K Katoh Y Takahashi K 《Veterinary parasitology》2011,177(1-2):97-103
The Rio Grande do Sul state, in Southern Brazil, is one of the foci of human cystic echinococcosis (CE). The sheep strain (G1) of Echinococcus granulosus and Echinococcus ortleppi (also known as cattle strain G5) have been reported before to infect livestock. However, up to the present, no molecular data are available on isolates of the E. granulosus complex from humans and dogs. The present study analyzed hydatid cysts from 6 CE patients and adult worms from 12 dogs. Sequencing of the mitochondrial cox1 and 12S rRNA genes detected the E. granulosus G1 genotype from four human cases, the G3 genotype (or buffalo strain) from one human case and E. ortleppi from another human case, respectively. Ten of the twelve dogs were found infected with the G1 genotype, and one dog each harbored worms of the G3 genotype and E. ortleppi. Obvious morphological differences were recognized between the G1 and E. ortleppi adult worms from dogs in this region. The buffalo strain (G3) is for the first time reported from South America. 相似文献