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71.
A water deficit during stage III of fruit growth was established with the aim of determining if it is possible to achieve an improvement in tree water status by summer pruning and fruit thinning. The experiment was set up as a randomized block split-plot design across trials (irrigation) where pruning was assigned to the main plot and fruit thinning to the sub-plots. The irrigation treatments were (1) standard full irrigation (FI), and (2) suppression of irrigation during stage III of fruit growth until leaves visibly withered (LWI); the pruning treatments were (1) experimental summer pruning (EP), and (2) standard summer pruning (CP); and three fruit thinning intensities were applied to facilitate analysis of the effects of the treatments in relation to fruit load. Changes in amount of light intercepted and in tree stem water potential (Psi stem) were evaluated. The EP treatment reduced the amount of light intercepted by the tree. In the FI treatment, there was a significant reduction in fruit growth measured as both water accumulation and dry mass accumulation. Under FI conditions, reductions in fruit load as a result of EP were not accompanied by a significant improvement in Psi stem. In the LWI treatment, EP produced a significant improvement of 0.17 MPa in Psi stem, but there was no improvement in fruit growth compared with CP trees. A reduction in fruit load from 350 (commercial load) to 150 per tree significantly improved Psi stem by 0.3 MPa at the end of stage III of fruit growth. These results indicate that improvements in water status in response to pruning may be insufficient to promote fruit growth if the pruned trees are unable to provide an adequate supply of assimilates to the developing fruits. 相似文献
72.
Weikum WM Vouloumanos A Navarra J Soto-Faraco S Sebastián-Gallés N Werker JF 《Science (New York, N.Y.)》2007,316(5828):1159
This study shows that 4- and 6-month-old infants can discriminate languages (English from French) just from viewing silently presented articulations. By the age of 8 months, only bilingual (French-English) infants succeed at this task. These findings reveal a surprisingly early preparedness for visual language discrimination and highlight infants' selectivity for retaining only necessary perceptual sensitivities. 相似文献
73.
Tania P. Lopes Jonatan Sanchez-Osorio Alfonso Bolarin Emilio A. Martinez Jordi Roca 《Veterinary journal (London, England : 1997)》2014,199(3):382-386
A field study was conducted to estimate seasonal differences in follicular development in weaned sows and to evaluate the implication of these differences on seasonal infertility. A total of 110 sows were selected at weaning during winter–spring (WS, n = 58) and summer–autumn (SA, n = 52). Ovaries were scanned once daily from weaning to the onset of oestrus and twice daily from then until ovulation. Six sows during WS were removed from study for not showing growing follicles at weaning. Oestrus was evaluated twice daily from day 1 after weaning to day 14 post-weaning. One of 52 (1.9%) sows in WS and 9/52 (17.3%) in SA showed no signs of oestrus within 14 days of weaning (P < 0.05). The diameters of the follicles at weaning, at the onset of oestrus and just before ovulation were smaller (P < 0.01) in SA sows than in WS sows. There were fewer follicles in SA sows than in WS sows just before ovulation (P < 0.05). Fifty of 51 (98.0%) sows in WS and 31/43 (72.1%) sows in SA experienced a weaning-to-oestrus interval (WOI) of 3–6 days (P < 0.05). Fifty-one of 52 (98.1%) sows in WS and 43/52 (82.7%) sows in SA were inseminated; the percentage of pregnant sows that failed to farrow was lower in WS (1/51, 2.0%) than in SA (5/43, 11.6%; P < 0.05). The percentage of farrowed sows was greater in WS (46/51, 90.2%) than in SA (32/43, 74.4%; P < 0.05). Sows in WS had on average 1.5 more piglets than sows in SA (P < 0.05). Sows with a WOI of 3–6 days had lower rates of pregnancy losses (P < 0.05) and higher farrowing percentages (P < 0.01) than those with a WOI > 6 days, irrespective of season. 相似文献
74.
Juan C González L Soriano JM Moltó JC Mañes J 《Journal of agricultural and food chemistry》2005,53(24):9348-9351
In this paper, accelerated solvent extraction (ASE) for the analysis of ochratoxin A (OTA) is applied for the first time. Optimization of the method is given for the extraction of OTA from rice samples. Several parameters such as type of solvent, temperature, pressure, static time, and cell size were investigated thoroughly to find the optimal extraction conditions. The optimum ASE operating conditions were methanol as extraction solvent, 1500 psi, 40 degrees C, 5 min of static time, 50% flush volume, 60 s of purge, 1 cycle, and 11 mL cell size. The total extraction time was approximately 15 min. OTA was determined by liquid chromatography coupled with a fluorescence detector and confirmed by methyl ester derivatization. The analytical performance of the method was monitored with quality control parameters. Finally, the optimized method was used to evaluate 12 rice samples, 1 of which was positive with an OTA content of 4.17 ng/g. The proposed method offers the possibility of a fast and simple process to obtain a quantitative extraction of OTA. 相似文献
75.
Jordi Marsal Merce Mata Jesus del Campo Amadeu Arbones Xavier Vallverdú Joan Girona Natalia Olivo 《Irrigation Science》2008,26(4):347-356
The use of partial root-drying (PRD) irrigation implies doubling pipelines instead of using a conventional single pipeline.
However, pipelines can be spaced a short distance apart (e.g. 1 m) along the vine row (“D” layout) or joined with cable ties
and laid as a single pipeline (“S” layout). Pipelines in “S” configuration are laid under the vine row, and in “D” at both
sides of the vine row. These two different layouts can change the wetted soil zone and affect grapevine response to irrigation.
The focus of this study was therefore on establishing the role of pipeline layout in vine-grape (cv. ‘Tempranillo’) response
under semi-arid conditions in which PRD is managed as a deficit irrigation technique. Six irrigation treatments were applied,
which resulted from the combination of Control (C, full irrigation), PRD and seasonal sustained deficit irrigation (SSDI),
and “S” and “D” pipeline layouts. SSDI and PRD were irrigated to 50% C throughout the irrigation season, and C irrigation
was scheduled according to a crop water balance technique. Midday stem water potential (Ψstem) and leaf conductance (gl) indicated that, on the whole, PRD treatments had a slightly higher water status than SSDI treatments, but a substantially
lower status than C treatments. Use of the “D” pipeline layout significantly reduced Ψstem in both PRD and SSDI treatments and in some instances for Control conditions, too. Berry yield, vine intercepted radiation,
leaf abscisic acid (ABA) and gl were highly correlated with Ψstem. Differences in water status between PRD-S and SSDI-S, according to a sub-surface irrigation test, seemed to be more related
to changes in soil evaporation losses and irrigation efficiency than to any intrinsic PRD effect. PRD-S accounted for water
savings equivalent to 10% according to the ratio between applied water and grape production for the SSDI-S treatment, whereas
PRD-D berry yield was not significantly different from that associated with the SSDI-S treatment. In conclusion, under the
growing conditions of this experiment, PRD-S offered the possibility of slightly improving water conservation when irrigation
was applied to the soil surface. 相似文献
76.
Water for irrigation is in short supply worldwide, therefore reduced irrigation options will have to be explored. We did this for ‘Golden Smoothee’ apple over the growing seasons of 2003-2005 at the IRTA-Estaciò Experimental de Lleida (41°37′ N; 0° 52′ E; 260 m a.s.l.), Catalonia, Spain. This region has a temperate climate with winter-dominant rainfall. Averages of annual rainfall and reference evapotranspiration over 2000-2009 were, respectively, 371 and 1023 mm. The treatments were: Control (C), receiving full irrigation; spring irrigation (SI), where at the budbreak 80 mm of water was applied followed by watering so that the total water applied in the season was either at 33% of C (SI-33) or at 50% of C (SI-50); and deficit irrigation (DI), where trees were irrigated either with 33% of C (DI-33) or with 50% of C (DI-50). Water in DI was applied either through one dripper per tree (DI-33-1d and DI-50-1d) or through two drippers per tree (DI-33-2d and DI-50-2d). Trees showed biennial bearing with 2004 being an ‘off-year’ when treatment effects on yield were largely masked by the higher values of stem water potential associated with lower crop loads. SI-50 and SI-33 performed poorly and cannot be recommended. For each of the DI treatments, the one-dripper version increased fresh market yield and fruit size. For example, although DI-50 performed better than DI-33, DI-33-1d was similar in performance to DI-50-2d. Under water shortage, we recommend whole-season application of DI-50-1d and DI-33-1d depending on the availability of water supply. 相似文献
77.
Josep Enric Valladares Rafael Ruiz De Gopegui Cristina Riera Jordi Alberola Montserrat Gállego Yvonne Espada Montserrat Portús Margarita Arboix 《Research in veterinary science》1998,64(3):195
Haemostatic alterations in dogs experimentally infected with Leishmania infantumwere studied before and after therapy with meglumine antimonate. Haemostatic function tests including platelet count, collagen-induced platelet aggregation, prothrombin time, activated partial thromboplastin time, thrombin time, plasma fibrinogen determination, and serum fibrinogen/fibrin degradation products concentration were performed. In the course of infection and before treatment, moderate thrombocytopenia (P<0·00001) decreased collagen induced platelet aggregation (P=0·0003), prolonged thrombin time (P=0·0117) and increased fibrinogen/fibrin degradation products were observed. Statistically significant differences of plasma fibrinogen concentration, prothrombin time, and activated partial thromboplastin time were not encountered. Haemostatic parameters returned to normal values after therapy. The results indicate that Leishmania infection may impair haemostasis suggesting induction of disseminated intravascular coagulation (DIC), and that treating dogs in an early stage of infection may potentially avoid the possibility of developing an uncompensated DIC. 相似文献
78.
Synergistic mortality between a neonicotinoid insecticide and an ergosterol‐biosynthesis‐inhibiting fungicide in three bee species 下载免费PDF全文
79.
80.
Christian Larrigaudière Ana Paula Candan Dolors Ubach Jordi Graell 《Postharvest Biology and Technology》2009,51(1):56-61
The aim of this work was to study the specific effects of low temperature and 1-MCP treatment on ethylene metabolism and oxidative behaviour in plums (Prunus × salicina cv. Larry Ann). Control fruit were stored at 20 °C or 0 °C and the 1-MCP (625 nL L?1) treated fruit at 0 °C. Changes in the kinetics of ethylene production upon removal were related to changes in ACC metabolism (ACC and MACC levels), oxidative behaviour (H2O2 content) and enzymatic antioxidant potential (SOD, CAT and POX enzymes) during cold storage. Low temperature stress inhibited the synthesis of MACC, which appeared to be the basic process that regulated ACC and ethylene production at ambient temperature. Although 1-MCP treatment inhibited ethylene production and ACC accumulation in the cold, it did not inhibit the accumulation of MACC. Neither cold nor 1-MCP treatment induced oxidative stress. Nevertheless, the 1-MCP treatment significantly impaired the increase in POX activity observed during cold storage. Collectively these results showed the underlying role that ACC metabolism plays in the ripening behaviour of cold-stored plums, confirming previous results. The results also indicate that MACC and malonyl transferase activity are the key regulatory factors that control ripening and possibly some ethylene-related disorders such as chilling injury in cold-stored plums. 相似文献