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1.
Vito Armando Laudicina Agata Novara Vito Barbera Markus Egli Luigi Badalucco 《Land Degradation \u0026amp; Development》2015,26(1):45-53
Several studies have reported how tillage and cropping systems affect quantity, quality, and distribution of soil organic matter (SOM) along the profile. However, the effect of soil management on the chemical structure of SOM and on its hydrophobic and hydrophilic components has been little investigated. In this work, the long‐term (19 years) effects of two cropping systems (wheat monoculture and wheat/faba bean rotation) and three tillage managements (conventional, reduced, and no tillage) on some chemical characteristics of SOM and their relationships with labile carbon (C) pools were evaluated. Soil samples were taken from the topsoil (0–15 cm) of a Chromic Haploxerert (central Sicily, Italy). After 19 years of different tillage and cropping systems management, total organic C significantly differed among treatments with the labile organic C pools showing the greater amount in no till and in wheat/faba bean plots. Hydrophobic and hydrophilic components of SOM, determined by diffuse reflectance infrared Fourier transform spectroscopy, were mainly affected by cropping system, whereas aromatic components of SOM by tillage. Soil organic matter components and characteristics showed significant correlations with the soil biochemical parameters, confirming the expected synergism between chemical and biochemical properties. This study demonstrated that (i) no tillage and crop rotation improve the chemical and biochemical properties of SOM of Vertisols under semiarid environment; and (ii) tillage management and cropping systems have affected, after 19 years, more the chemical and biochemical properties of SOM than its quantity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
2.
A bioassay for insulin-like growth factor (IGF), based on the in vitro incorporation of [35S]-sulfate into gill arch tissue was used to study the hormonal regulation of proteoglycan synthesis in the goldfish (Carassius auratus). [35S]-sulfate incorporation into gill arch tissue was found to be time-dependent with maximal uptake occurring by 48h, suggesting that proteoglycan synthesis in this tissue was maintained for at least 48h in vitro. The addition of human recombinant IGF-I (IGF-I) to the incubation medium was found to significantly stimulate [35S]-sulfate uptake into the gill arches, whereas bovine growth hormone (GH) was without effect. Porcine insulin was also stimulatory, but results indicate that the effects of porcine insulin and IGF-I may be mediated by a single receptor system. Finally, arches from hypophysectomized fish were significantly less responsive to IGF-I than were arches from sham-operated fish. Furthermore, administration of ovine GH in vivo appeared to increase subsequent responsiveness in vitro. Together, these results provide evidence that the growth-promoting actions of GH in the goldfish may be mediated, at least in part, by a peptide related in structure to mammalian IGF-I. 相似文献
3.
Andrzej K Siwicki Zdzisaw Zak John C Fuller Jr Steven Nissen Sylwia Trapkowska Edward Gbski Agata Kowalska Krzytof Kazu & Elbieta Terech-Majewska 《Aquaculture Research》2006,37(2):127-131
Studies have shown that in both in vitro and in vivo tests, β‐hydroxy‐β‐methylbutyrate (HMB) increases the nonspecific cellular and humoral immune response and protection against diseases in animals. The present study examines the influence of HMB on nonspecific humoral defense mechanisms and protection against furunculosis in pikeperch (Sander lucioperca). β‐hydroxy‐β‐methylbutyrate was fed in a pelleted ration of 50 mg kg?1 feed day?1 for 4 weeks. Blood was drawn from 12 HMB‐fed and control‐fed pikeperch. The lysozyme and ceruloplasmin activities in the plasma, total immunoglobulin (Ig) levels, and total serum protein were analysed prior to and then after 2 and 4 weeks of HMB ingestion. After 4 weeks of HMB ingestion, a challenge test was performed by injecting the fish with live pathogenic Aeromonas salmonicida bacteria. β‐hydroxy‐β‐methylbutyrate at a dose of 50 mg kg?1 feed resulted in a statistically significant (P<0.05) increase in the lysozyme activity of the plasma, total Ig, and serum protein levels. Additionally, reduced mortality (40%) after the in vivo challenge with pathogenic A. salmonicida suggested that HMB‐activated nonspecific protection against furunculosis in pikeperch. 相似文献
4.
Nigro Domenica Giove Stefania L. Colasuonno Pasqualina de Pinto Roberta Marcotuli Ilaria Gadaleta Agata 《Genetic Resources and Crop Evolution》2022,69(6):2191-2202
Genetic Resources and Crop Evolution - Durum wheat (T. turgidum L. var. durum) is one of the most widely cultivated cereal crop in the Mediterranean area. Its production has been triggered by... 相似文献
5.
Activities of five enzymes, sucrose synthase (SUS), uridine 5'-diphosphate glucose pyrophosphorylase (UDPGPPase), fructose-1,6 bisphosphatase (FBPase), adenosine 5'diphosphate glucose pyrophosphorylase (ADPGPPase) and starch synthase (STS), in the metabolic pathway of starch synthesis, were compared between two sweet potato ( Ipomoea batatas Lam.) cultivars, Koganesengan (C.V.KOG, a recently released high yield cultivar) and Tsurunasigenji (C.V.TSU, an old, local cultivar with poor yield). The measurements were carried out using the root samples (tuberous, thick and fibrous roots) harvested at the fast tubering stage. Of the five enzymes, SUS, ADPGPPase and STS showed high activities in the tuberous root, particularly in that of C.V.KOG, and a similar trend was observed for activities of these enzymes on a protein basis. The increased activity of the three enzymes is considered to be one of the characteristics in a high yield cultivar, allowing the root to function effectively as a starch synthesis and storage organ. 相似文献
6.
Characterization of dinucleotide and trinucleotide EST-derived microsatellites in the wheat genome 总被引:6,自引:0,他引:6
Over the past decade microsatellites or simple sequence repeats (SSRs) have attracted a considerable amount of attention from
researchers. The aim of the present paper was to analyse expressed sequence tag-derived SSR (EST-SSR) marker variability in
wheat and to investigate the relationships between the number and type of repeat units and the level of microsatellite polymorphism.
Two hundred and forty-one new EST-SSR markers available in a public database () were characterized in eight durum wheat cultivars (Svevo, Ciccio, Primadur, Duilio, Meridiano, Claudio, Latino, Messapia),
two accessions of Triticum turgidum var. dicoccoides (MG4343, MG29896), one accession of T. turgidum var. dicoccum (MG5323) and in the common wheat cv. Chinese Spring. Of these, 201 primer pairs (83.4%) amplified PCR products successfully,
while the remaining 40 (16.6%) failed to amplify any product. Of the EST-SSRs analysed, 45.2% of the primer pairs amplified
one or two PCR products. Multiple discrete PCR products were observed among both di- and trinucleotide EST-SSR markers (31.2
and 40.5%, respectively). Markers based on dinucleotide microsatellites were more polymorphic than those based on trinucleotide
SSRs in the 12 wheat genotypes tested (68.9 and 52.7%, respectively). An average of 2.5 alleles for dinucleotide and 2.0 alleles
for trinucleotide SSRs was observed. The data reported in the present work indicate the presence of a significant relationship
between motif sequence types and polymorphism. The primer set based on the AG repeat motif showed the lowest percentage of
polymorphism (55.0%), while the primer set based on the AC repeat motif showed t he highest percentage (85.0%). Among trinucleotide
SSRs, the AGG microsatellite markers showed the highest percentage of polymorphism (70.0%), and the ACG motif the lowest value
(25.0%). The characterization of these new EST-SSR markers and the results of our studyon the effect of repeat number and
type of motifs could have important applications in the genetic analysis of agronomically important traits, quantitative trait
locus discovery and marker-assisted selection. 相似文献
7.
A mathematical model is presented that predicts, as a function of distance downwind, the height of the center line of a single visible plume from a wet natural-draft cooling tower in moderate to strong winds. The analytic method is quasi-Lagrangian; that is, the behavior of a small section or parcel of the plume is analyzed as a function of time. Eight first-order differential equations describe the parcel in terms of change in mass, vertical velocity, vertical displacement, length of side, temperature, mass of liquid water, horizontal velocity, and horizontal displacement. The equations are tractable for solution by well-known computer integration techniques. The model was tested on plumes from four cooling towers at an electric generating plant, and its predicted plume path was compared with data interpreted from time-lapse photographs of the plumes. Best results were obtained by applying dry plume entrainment rates in the early stages and cloud entrainment rates in the later stages. The computed prediction, employing reasonable estimates where necessary, closely approximated the photographic data for a distance of 1500 m downwind on a day with high relative humidity. The model can also be used to analyze the nature of wet plume behavior. 相似文献
8.
Dams I Bialoniska A Ciunik Z Wawrzenczyk C 《Journal of agricultural and food chemistry》2004,52(6):1630-1634
Starting from (R)-(+)- and (S)-(-)-pulegone, enantiomeric pairs of esters and lactones with the p-menthane system were obtained. The Claisen rearrangement of allylic alcohols and iodolactonization of gamma,delta-unsaturated acids were the key steps of syntheses presented. The structures of compounds were determined by both spectroscopic and crystallographic methods. Some of the synthesized compounds are characterized by interesting odoriferous properties. 相似文献
9.
10.
Bibring JP Langevin Y Mustard JF Poulet F Arvidson R Gendrin A Gondet B Mangold N Pinet P Forget F Berthé M Bibring JP Gendrin A Gomez C Gondet B Jouglet D Poulet F Soufflot A Vincendon M Combes M Drossart P Encrenaz T Fouchet T Merchiorri R Belluci G Altieri F Formisano V Capaccioni F Cerroni P Coradini A Fonti S Korablev O Kottsov V Ignatiev N Moroz V Titov D Zasova L Loiseau D Mangold N Pinet P Douté S Schmitt B Sotin C Hauber E Hoffmann H Jaumann R Keller U Arvidson R Mustard JF Duxbury T 《Science (New York, N.Y.)》2006,312(5772):400-404
Global mineralogical mapping of Mars by the Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activité (OMEGA) instrument on the European Space Agency's Mars Express spacecraft provides new information on Mars' geological and climatic history. Phyllosilicates formed by aqueous alteration very early in the planet's history (the "phyllocian" era) are found in the oldest terrains; sulfates were formed in a second era (the "theiikian" era) in an acidic environment. Beginning about 3.5 billion years ago, the last era (the "siderikian") is dominated by the formation of anhydrous ferric oxides in a slow superficial weathering, without liquid water playing a major role across the planet. 相似文献