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Marino Fernández-Falcón Carlos E. Alvarez María M. Hernández 《Journal of plant nutrition》2013,36(6):1018-1032
A study of nutrient removal was carried out in commercial protea plantations of each of the cultivars ‘Scarlett Ribbon,’ ‘High Gold,’ ‘Veldfire,’ and ‘Sunrise’ of Leucospermum cordifolium, and of the species L. patersonii,located in a subtropical region (La Palma, Canarian Archipelago). Flowering stems of optimal commercial quality were taken from each of the mentioned cultivars and species, once a year (2003 and 2004) at harvest time (January to April), and the different organs were analyzed separately. Flowering stems of the cultivars ‘High Gold’ and ‘Veldfire’ presented the highest contents of most studied nutrients, whereas the opposite was observed in ‘Scarlett Ribbon’ and L. patersonii. Mean yields of flowering stems varied very much among cultivars, and the highest ones were those of ‘High Gold’ and ‘Scarlett Ribbon’. The cultivar ‘High Gold’ removed the highest quantities of studied nutrients, and the contrary was observed in L. patersonii for most of them. Suitable rates of nitrogen (N): phosphorus (P): potassium (K) fertilizers for nutrient restitution purposes were 1:0.08:0.40 for ‘Scarlett Ribbon,’ 1:0.08:0.66 for ‘High Gold,’ 1:0.08:0.38 for ‘Veldfire,’ 1:0.09:0.75 for L. patersonii;and 1:0.18:1.11 for ‘Sunrise’. 相似文献
54.
G. Lanteri F. Macrì F. Marino S. Caracappa G. Mazzullo 《Anatomia, histologia, embryologia》2013,42(5):394-397
Male cross‐breed lamb conjoined twins were sent for examination. The twins came from a farm located in the outskirts of Palermo. The twins were spontaneously delivered and found dead by the farmer. X‐ray examination and necropsy were performed. The deformity was identified as deradelphus cephalo‐thoracoomphalopagus. This condition has never been reported in veterinary literature. Our case reports of male conjoined twins characterized by two separated hearts with their own pericardial sacs and two separated livers. These findings represent a rare condition in conjoined twinning. 相似文献
55.
Grazia Marino Claudio Buscaroli 《The Journal of Horticultural Science and Biotechnology》2013,88(5):670-675
SummaryThe present paper reports on somaclonal variation of leaf-derived ‘Tomuri’ and ‘Hayward’ somaclones regenerated at variable pH, and the effect of the in vitro selection pressure on their tolerance to lime-induced iron chlorosis as adult plants in pots and in the field. In most plants grown in pots, the above ground component length (AGL) and the node number (NN), and also root weight of ‘Hayward’, tended to increase with the regeneration pH (RpH). The higher vigour of ‘Hayward’ somaclones regenerated at high pH seemed to be confirmed in the field. In contrast, the pH selection pressure during regeneration had no clear effect on plant tolerance to lime. For ‘Hayward’, the group of somaclones obtained at pH 5.7 showed at high lime levels higher average AGL and NN than those of plants regenerated at pH 7; while clone 7.5-1, the only surviving somaclone among those obtained at the highest pH, was apparently the most tolerant to lime. The percentage of ‘Tomuri’ somaclones obtained at pH 7.5 that seemed less sensitive to lime was slightly higher than those of somaclones regenerated at pH 5.7 and 7. ‘Tomuri’ and ‘Hayward’ controls were both very sensitive to lime. Some somaclones which had been able to grow at high pH in vitro were also fairly tolerant to lime when cultured in pots and/or in the field, especially ‘Tomuri’ 5.7-5, -6; 7-6, -8, -14 and 7.5-6, and ‘Hayward’ 5.7-5; 7-2, -3, -5 and 7.5-1. The in vitro regeneration and selection methods here described therefore seem useful for creating and selecting new variability in kiwifruit and promising for obtaining plants tolerant to high pH and lime levels in the soil. 相似文献
56.
Nicole Pacini Ambrosius Josef Martin Dörr Antonia Concetta Elia Melissa Scoparo Maria Cesarina Abete Marino Prearo 《Fish physiology and biochemistry》2014,40(5):1609-1619
In 2007, renal failure and death in pets were linked to pet food containing both melamine (MEL) and cyanuric acid (CYA). In mammals and fish, the co-administration of MEL and CYA causes renal crystal formation. Moreover, little is known about the process of crystal removal in fish. The aim of this study was to evaluate the formation of MEL–cyanurate crystals in kidney of rainbow trout (Oncorhynchus mykiss) fed combined MEL and CYA diets for 10 weeks at 250, 500 and 1,000 mg/kg in feed (equivalent to 2.5, 5, 10 mg/kg body weight of trout fed 1 % body weight per day). During the exposure trial and throughout a withdrawal period, prooxidant effects of MEL and CYA were evaluated on oxidative stress markers such as catalase, glutathione S-transferase and malondialdehyde. Crystal formation was dose and time dependent, and after six withdrawal weeks, crystals persisted in kidney of trout treated the highest triazine dose. Catalase and glutathione S-transferase activity in kidney of trout exposed to both triazines for 10 weeks indicated that MEL (with or without CYA) can exert a higher prooxidant effect than CYA dispensed singly. Although the enzymes activity increase appears to be reverted after two MEL withdrawal weeks, persistence of crystals may lead to severe damage in renal cells of fish. 相似文献
57.
Filipe Selau Carlos Naihana Schaffer Robson Andreazza Lawrence A Morris Marino José Tedesco Cácio Luiz Boechat 《Communications in Soil Science and Plant Analysis》2018,49(3):319-333
Irrigation with treated wastewaters can improve nutrient levels and yield of crops planted on degraded soils. This study evaluated how irrigation with treated industrial wastewater affected biomass production and nutrition of maize plants and physio-chemical properties of a degraded soil. The experiment was conducted in a greenhouse using PVC columns. Treatments consisted of 8 treatments irrigated with clean water and increasing doses of N and P, and 8 treatments with 4 proportions of wastewater irrigation (25%, 50%, 75% and 100% v/v). In general, maize biomass did not differ between irrigation water sources. Differences were largely associated with N nutrition. We observed increases in concentrations of N, P, K, S, Mn, Na, Cu, and Zn in tissue of maize under irrigation with wastewater. The addition of treated wastewater increased the P and Na concentrations, and EC values in the soil without affecting clay dispersion in water. An associated economic analysis indicated that wastewater irrigation would not be economically feasible without including environmental benefits. In southern Brazil, the proportion of irrigation water that is wastewater should not exceed 50%. 相似文献
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PO Wennberg TF Hanisco L Jaegle DJ Jacob EJ Hintsa EJ Lanzendorf JG Anderson R Gao ER Keim SG Donnelly LAD Negro DW Fahey SA McKeen RJ Salawitch CR Webster RD May RL Herman MH Proffitt JJ Margitan EL Atlas SM Schauffler F Flocke CT McElroy TP Bui 《Science (New York, N.Y.)》1998,279(5347):49-53
The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected. 相似文献
60.
Humorally deficient, in ovo-bursectomized (Bx) and sham-Bx chickens were vaccinated twice, 1 month apart, with Newcastle disease virus (NDV) Roakin strain and challenged with a velogenic viscerotropic NDV strain via the oronasal route. Hemagglutination-inhibition and seroneutralization tests showed that Bx chickens had reduced antibody-mediated immunity to virus infection. In contrast, they had significantly higher cell-mediated immunity (CMI) before challenge, as estimated simultaneously by determination of blastogenic capacity of peripheral blood lymphocytes induced by phytohemagglutinin and by specific antigen stimulation. After virus challenge, there was transitory inhibition of CMI based on marked reductions in levels of stimulation indices, and this impairment in CMI was supported by persistence of virus in Bx chickens for longer periods. Bx chickens resisted challenge, even though antibody titers were well below those considered predictive of resistance to challenge, suggesting that CMI provides a degree of resistance to velogenic NDV. 相似文献