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991.
Alan Mario Zuffo Joacir Mario Zuffo Júnior Rezânio Martins Carvalho Adaniel Sousa dos Santos João Batista da Silva Oliveira Wéverson Lima Fonseca 《Journal of plant nutrition》2017,40(9):1332-1338
The definition of nitrogen doses for baru species becomes necessary because each forest species responds differently to nitrogen fertilization. The aim of this study was to evaluate baru seedlings' response to nitrogen, phosphorus, and potassium (NPK) fertilization and liming. The experiment was conducted in a greenhouse in a randomized blocks design, arranged in a 5 × 2 factorial scheme, being the factors consisted of five doses of nitrogen in covering (0, 75, 150, 225, and 300 mg dm?3) and substrate with and without limestone and PK, with four replications. At 60 days after transplanting, the plant height, stem diameter, number of leaflets, leaf area, shoot dry mass, chlorophyll content, N content in the leaves, root length, root volume, root dry mass, height/stem diameter ratio, shoot dry mass/root dry mass ratio, and Dickson quality index were evaluated. The substrate with liming influences positively the root dry mass. Nitrogen and PK fertilization promote increase in the relative chlorophyll content and N concentration in the leaves. 相似文献
992.
Roberto G. Chiquito-Contreras Bernardo Murillo-Amador Cesar J. Chiquito-Contreras Jhovana C. Márquez-Martínez Miguel V. Córdoba-Matson 《Journal of plant nutrition》2017,40(18):2595-2601
The habanero pepper is widely used in a variety of commercial food products. The increase in the cultivation area of the habanero pepper has increased the use of agricultural inputs, mainly inorganic fertilizers, which have high economic costs and cause negative effects to the soil and water. In recent years, the use of beneficial soil microorganisms has been studied as an alternative to inorganic fertilizers. In the present study, the effect of three strains of Pseudomonas putida on the growth and productivity of King Pakal hybrid habanero pepper with limited inorganic fertilizer in a greenhouse. It was found that a reduction of inorganic fertilizer application of 25% with P. putida rhizobacteria strains increased or maintained growth and productivity of King Pakal hybrid habanero pepper. Before these rhizobacteria can be used in the field, results will first need to be confirmed under more natural conditions. 相似文献
993.
Jan Mertens Jörn Germer José Coelho de Araújo Filho Joachim Sauerborn 《Archives of Agronomy and Soil Science》2017,63(7):969-983
In order to develop a method for extensive pomiculture on marginal soils in semiarid Brazil, a field experiment was conducted to study the impacts of the soil conditioners biochar, clay substrate and goat manure on soil physical parameters of a sandy soil and on seedling performance of Spondias tuberosa Arruda. Manure significantly increased total porosity, soil water content and reduced bulk density of the sandy soil. Water content at field capacity (θfc) and at permanent wilting point (θpwp) were increased due to manure application. Neither biochar nor clay substrate had a significant impact on the soil physical parameters. Biochar combined with clay substrate led to lower soil water content and significantly reduced the period of retaining atmospheric water. Due to a strong correlation (R2 = 0.75) between θfc and θpwp, the available water capacity within all treatments remained unchanged. Amelioration and initial nutrient supplies had no effect on seedling survival and stem growth of S. tuberosa during the 23-month experiment. This underlines the nondomesticated character of the available plant material of S. tuberosa. The independence of the seedling performance of soil management makes S. tuberosa an interesting species for low-input orchards and for reforestation within the Caatinga. 相似文献
994.
Ángeles Martínez-Toledo Angel Montes-Rocha Donaji J. González-Mille Guillermo Espinosa-Reyes Arturo Torres-Dosal Jesús J. Mejia-Saavedra César A. Ilizaliturri-Hernández 《Journal of Soils and Sediments》2017,17(2):364-375
Purpose
San Luis Potosí is one of the largest metal producers; mining activity has been responsible for metal emissions for over 100 years, from several sources (deposits, tailings, effluents, and dusts) generating effects in human and ecosystem health. The objective of this study was to evaluate the effect of the concentrations of heavy metals in the soil health of four municipalities of San Luis Potosí contaminated with mine tailings, using enzyme activity as a biochemical endpoint.Materials and methods
Four municipalities contaminated with residues of historical mining activity were analyzed (25 topsoil samples per type of site contaminated and reference). The parameters that were analyzed included pH; organic matter (OM); electrical conductivity (EC); percentage of clay, As, Cd, Cr, Cu, Hg, Pb, and Zn; and arylsulfatase (ARS), β-glucosidase (BG), urease (UR), and fluorescein diacetate hydrolysis (FDA) activities in soil. Differences among the parameters per municipality and type of site were evaluated using a factorial analysis of variance. The relationships were analyzed by Pearson’s correlation and a stepwise distance-based linear model permutation test (DistLM). Results were visualized using a distance-based redundancy analysis (dbRDA). A hazard quotient (HQ) for metals was calculated in order to estimate the effects on soil microbial processes.Results and discussion
A concentration gradient (mg/kg) of Zn (4744.5–65,585.7), Pb (1321.0–31,932.2), As (ND-8736.7), and Cu (130.9–8475.4) was found in the contaminated sites. The HQ showed a very high hazard level for the elements detected in all contaminated sites (1.4–655.8). The pattern of enzymatic inhibition found was ARS (95.8 %), UR (90.6 %), FDA (86.9 %), and BG (76.0 %). Strong negative relationships were observed among enzymatic activities and heavy metals in the following inhibitory effect Cu > As > Zn > Pb. Metals and covariables explained from 84 to 86 % of variability in enzyme activity. EC, Cu, and As showed a strong inhibitory effect; and parameters such as OM, pH, and clay were found to have a slightly inducing effect.Conclusions
In this study, the heavy metal concentrations were higher than the ones obtained in other reports for this region. The HQ reveals the presence of possible risks for the health of life in the region. The decrease of enzyme activities in soil could trigger adverse changes in the flow of matter and energy in ecosystems. This study provides a field baseline that could be part of a long-term monitoring program for these locations.995.
Cecilia Castro Laura Gazza Roberto Ciccoritti Norberto Pogna Cesare Oliviero Rossi Cesare Manetti 《Journal of Cereal Science》2010
Spikes and seeds from diploid ‘einkorn’ wheat Triticum monococcum and two near-isogenic hard and soft common wheat (Triticum aestivum) lines were harvested at regular intervals from 7 days post-anthesis (dpa) and analysed by non-destructive magnetic resonance imaging (MRI) and time domain-nuclear magnetic resonance (TD-NMR). A large amount of free water occurred in rachises, glumes and awns of spikes collected at 7 dpa, and accumulated in the physiologically active cells of the endosperm at 21 dpa. In the final stages of kernel development, awns and seed embryos exhibited a high MR signal due to the presence of free water likely associated with biological activities. TD-NMR relaxation time distributions obtained by discrete exponential fitting, distributed exponential fitting and SLICING multivariate analysis offered detailed information on mobility behaviour of water molecules in developing seeds and were able to differentiate two soft and hard isolines from common wheat cv. Enesco at early stages of seed development. 相似文献
996.
Patrícia Mendon?a Pauletti Lucas Silva Cintra Caio Guedes Braguine Ademar Alves da Silva Filho Márcio Luís Andrade e Silva Wilson Roberto Cunha Ana Helena Januário 《Marine drugs》2010,8(5):1526-1549
This review discusses the isolation, structural elucidation, and biological activities of halogenated indole alkaloids obtained from marine invertebrates. Meridianins and related compounds (variolins, psammopemmins, and aplicyanins), as well as aplysinopsins and leptoclinidamines, are focused on. A compilation of the 13C-NMR spectral data of these selected natural indole alkaloids is also provided. 相似文献
997.
Daniel Goitom Asfaha Christophe R. Quétel Freddy Thomas Micha Horacek Bernhard Wimmer Gerhard Heiss Christian Dekant Peter Deters-Itzelsberger Stefan Hoelzl Susanne Rummel Christophe Brach-Papa Marleen Van Bocxstaele Eric Jamin Malcolm Baxter Katharina Heinrich Simon Kelly Daniela Bertoldi Luana Bontempo Federica Camin Roberto Larcher Matteo Perini Andreas Rossmann Antje Schellenberg Claus Schlicht Heinz Froeschl Jurian Hoogewerff Henriette Ueckermann 《Journal of Cereal Science》2011
The aim of this work (from the FP6 project TRACE) was to develop methods based on the use of geochemical markers for the authentication of the geographical origin of cereal samples in Europe (cf. EC regulations 2081/92 and 1898/06). For the first time, the potential usefulness of combining n(87Sr)/n(86Sr) and δ13C, δ15N, δ18O and δ34S isotopic signatures, alone or with key element concentrations ([Na], [K], [Ca], [Cu] and [Rb], progressively identified out of 31 sets of results), was investigated through multiple step multivariate statistics for more than 500 cereal samples collected over 2 years from 17 sampling sites across Europe representing an extensive range of geographical and environmental characteristics. 相似文献
998.
999.
Singh A Boston SE Poma R 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(7):757-760
Thymoma-associated exfoliative dermatitis was suspected in a cat with a cranial mediastinal mass. The dermatopathy resolved with surgical removal of a thymoma. The cat manifested neurologic signs consistent with myasthenia gravis 7 wk after surgery. Exfoliative dermatitis and post-thymectomy myasthenia gravis in the same cat has not been reported previously. 相似文献
1000.
Fabio R. Braga Jackson V. Araújo André. R. Silva Rogério O. Carvalho Juliana M. Araujo Sebastião R. Ferreira Laércio A. Benjamin 《Tropical animal health and production》2010,42(6):1161-1165
This work was performed to determine the predatory capacity in vitro of the nematophagous fungus Duddingtonia flagrans (isolate AC001) on cyathostomin infective larvae of horse (L3). The experimental assay was carried out on plates with 2% water-agar (2% WA). In the treated group, each plate contained
1.000 L3 and 1.000 conidia of the fungus. The control group without fungus only contained 1.000 L3 in the plates. Ten random fields (4 mm diameter) were examined per plate of treated and control groups, every 24 h for seven
days under an optical microscope (10× and 40× objective lens) for non-predated L3 counts. After 7 days, the non-predated L3 were recovered from the Petri dishes using the Baermann method. The interaction there was a significant reduction (p < 0.01) of 93.64% in the cyathostomin L3 recovered. The results showed that the D. flagrans is a potential candidate to the biological control of horse cyathostomin L3. 相似文献