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1.
This research aims to investigate the relationship between the solvent retention capacity (SRC) test and quality assessment of hard red spring (HRS) wheat flour samples obtained from 10 HRS cultivars grown at six locations in North Dakota. The SRC values were significantly (P < 0.05) correlated with flour chemical components (protein, gluten, starch, and damaged starch contents, except arabinoxylan); with farinograph parameters (stability [FST], water absorption, peak time [FPT], and quality number); and with breadmaking parameters (baking water absorption [BWA], bread loaf volume [BLV], and symmetry). Differences in locations and cultivars contributed significantly to variation in quality parameters and SRC values. Suitability of SRC parameters for discriminatory analysis of HRS wheat flour is greatly influenced by molecular weight distribution (MWD) of SDS‐unextractable proteins. SRC parameters, except for sucrose SRC, showed significant (P < 0.01) and positive correlations with high‐molecular‐weight (HMW) polymeric proteins in SDS‐unextractable fractions, whereas only lactic acid SRC exhibited significant (P < 0.01) correlations with low‐molecular‐weight polymeric proteins. HMW polymeric proteins also exhibited positive associations with FPT, FST, BWA, and BLV. The discrepant variation in association of SRC parameters with respect to MWD of SDS‐unextractable proteins could improve segregation of HRS wheat flour samples for quality. 相似文献
2.
Sara Pourhosein Sarameh Amir Houshang Bahri Bahram Falahatkar Mahtab Yarmohammadi Alireza Salarzadeh 《Aquaculture Nutrition》2019,25(3):543-554
The aim of this study was to evaluate the long‐term effects (7‐month experiment) of diets consisting of fish oil (Kilka fish) and vegetable oil (rapeseed) on the reproductive performance of sterlet sturgeon (Acipenser ruthenus) broodstock. Forty‐five broodstock (990.3 ± 20.05 g) were randomly allocated to three different diet treatments. Three experimental diets were formulated with graded levels of fish oil (100% FO), vegetable oil (100% VO), and a combination of fish and vegetable oil (50% FO + 50% VO). At the end of the 7‐month feeding trial period, the weight gain and final weight were changed significantly different between the treatments (p < 0.05). Broodstock fed the FO + VO diet had higher growth than those fed the only FO or VO diets (p < 0.05). The highest germinal vesicle migration percentage was observed in FO + VO treatment (p < 0.05). The DHA/EPA, DHA/ARA and EPA/ARA ratios in oocyte exhibited a significant difference in the different treatments (p < 0.05). This study indicates that nutrition of broodstock with diet including FO + VO (p < 0.05) can positively affect the growth performance of larvae compared with only FO or VO diets. Furthermore, the high levels of 18:1n‐9, AL and ALA contents in oocytes from broodstock fed VO and the lowest ALA content in oocytes from broodstock fed FO underlined the important role of broodstock diets in the reproductive process and embryonic and/or larval developments of sterlet. 相似文献
3.
Ines Zrafi-Nouira Zouhour Khedir-Ghenim Raouf Bahri Imed Cheraeif Mahmoud Rouabhia Dalila Saidane-Mosbahi 《Water, air, and soil pollution》2009,201(1-4):19-31
In this study, the occurrence of toxic heavy metals (As, Cd, Cr, Cu, Pb, and Zn) and relative bioaccumulation in biota samples were investigated in a freshwater ecosystem, the Basento river, one of the main aquatic systems in the south of Italy, which over the last years has been transformed into a sink of urban and industrial wastes. Therefore, the levels of arsenic, cadmium, chromium, copper, lead, and zinc were determined in water, sediments, and tissues of some macroinvertebrate—which are natural assessment endpoints for the evaluation of ecological risk in aquatic systems. Accumulation factors, as a ratio between the concentration of a given contaminant in biota and the one in an abiotic medium, were considered in order to estimate heavy metal contamination loads in biota. Statistical analysis was performed for a comparative evaluation of bioaccumulation among various macroinvertebrates, according to different feeding guilds. The Tukey honestly significantly different test showed significant differences in the bioaccumulation of As, Cd, and Cr among the considered biological receptors (collector–gatherer, predator, and filterer), suggesting that the biological uptake from immediate contact with the sediment or solid substratum (collector–gatherer), instead of the bioconcentration from water (filterer) or biomagnification along the biotic food webs (predators), is the more effective biological sequestering pathway for these metals. Biota–sediment accumulation factors, commonly used for the evaluation of sediment’s role in aquatic systems contamination, were determined for the considered metals. A linear correlation between the concentrations of As, Cd, Cr, and Zn in macroinvertebrates and those in the sediments suggested that the metal uptake data in macroinvertebrates can provide useful information for the estimation of heavy metal exposure risk or bioavailability when making assessments of sediment toxicity in freshwater ecosystems. 相似文献
4.
De Feo V Bruno M Tahiri B Napolitano F Senatore F 《Journal of agricultural and food chemistry》2003,51(13):3849-3853
The chemical composition of essential oils from aerial parts of Thymus spinulosus Ten. (Lamiaceae) is reported. Four oils from plants growing in different environmental conditions were characterized by GC and GC-MS methods; the oils seem to indicate a new chemotype in the genus Thymus. Influences of soil and altitude characteristics on the essential oil composition are discussed. The oils showed antibacterial activity against Gram-positive (Staphylococcus aureus, Streptococcus faecalis, Bacillus subtilis, and Bacillus cereus) and Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella typhimuium Ty2, and Pseudomonas aeruginosa) bacteria. 相似文献
5.
A new Myxosporea, Zschokkella soleae sp. n., was found in the gall bladder and the bile of common sole, Solea solea (L.), from Ghar El Melh Lagoon in north‐east Tunisia. This is the first record for the presence of Zschokkella species in Tunisian waters. The parasite's plasmodia are polysporic with variable size and shape. Some plasmodia appeared attached to the gall bladder epithelium while others were found free in bile. Mature spores are ellipsoidal in frontal view 13.8 ± 0.38 μm long and 10.86 ± 0.40 μm wide with two equal size spherical polar capsules 3.6 ± 0.43 μm in size. The prevalence of infection seems to correlate with host size and changes over the year with maximum percentage in summer. Based on the 18S rDNA sequence data, Z. soleae sp. n. is readily distinguishable from other myxozoan DNA sequences in GenBank. Phylogenetically, the new species is placed in the freshwater Myxidium clade including several Zschokkella spp. infecting the gall bladder. Morphology, histology as well as DNA sequence analysis indicate that the examined species differs from all previously described Zschokkella species. 相似文献
6.
Thermal generalist behaviour of invasive Puccinia striiformis f. sp. tritici strains under current and future climate conditions 
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下载免费PDF全文 C. de Vallavieille‐Pope B. Bahri M. Leconte O. Zurfluh Y. Belaid E. Maghrebi F. Huard L. Huber M. Launay M. O. Bancal 《Plant pathology》2018,67(6):1307-1320
Yellow rust is a devastating wheat disease. Since 2000, Puccinia striiformis f. sp. tritici strains PstS1 and PstS2 have become adapted to high temperatures and have spread worldwide. By 2011, Warrior strains had invaded both warm and cold areas of Europe. This study questioned whether thermal aptitude promoted the spread of Warrior strains, similar to PstS1/PstS2, by comparing infection efficiency (IE) at five temperatures and latent period (LP) under warm and cold regimes for Warrior isolates and pre‐2011 reference strains on two susceptible wheat varieties. The Warrior isolates showed a range of IE and LP responses to temperature that was intermediate between the northern reference isolates adapted to cold conditions and both the southern and invasive PstS2 isolates adapted to warm conditions. Warrior isolates had the highest IE under optimal temperatures of 10 and 15 °C, and displayed reduced infectivity under the warmest (20 °C) and coldest (5 °C) temperatures. Warrior strains acted as thermal generalists and the reference isolates acted as specialists. An IE thermal response was used to simulate the development of each isolate under future climate scenarios in a temperate and Mediterranean region. Isolates had the same ranking for yearly IE over the three 30‐year periods (1971–2000, 2021–2050, 2071–2100) and both locations, with a slight infection increase in the future. However, in the future IEs increased in earlier months. The thermal generalist profile of Warrior isolates for IE was confirmed, with an intermediate capacity to tolerate warming climate, whereas the southern isolates are better adapted to warm conditions, but do not have the virulences necessary to develop on current varieties. 相似文献
7.
Bochra Laribi Iness Bettaieb Karima Kouki Ali Sahli Abdelaziz Mougou Brahim Marzouk 《Industrial Crops and Products》2009,30(3):372-379
The Mediterranean region suffers of drought which affects plant behaviour regarding biochemical responses. Accordingly, the effects of water deficit on growth, essential oil and fatty acid composition of caraway (Carum carvi L.) seeds were investigated. Plants were treated with different levels of water deficit: control, moderate water deficit and severe water deficit. Plant growth (height, fresh and dry matter weight) was significantly reduced by severe water deficit. This last caused also important reductions of the seed yield and yield components. Drought decreased significantly seed total fatty acid contents and particularly the petroselinic ones whose proportions decreased significantly by 12.17 and 18.47%, in comparison with the control, under moderate water deficit and severe water deficit, respectively. Besides, moderate water deficit increased the essential oil yield (expressed as g/100 g on the basis of dry matter weight). The main essential oil constituents were carvone and limonene which showed an increasing of their contents under water deficit levels. Thus, water deficit induced a significant reduction in growth parameters and fatty acid content, and an increase in the essential oil compounds. These bioactive compounds have been required in many industrial products. 相似文献
8.
Rola El Amil Sajid Ali Bochra Bahri Marc Leconte Claude de Vallavieille-Pope Kumarse Nazari 《Plant pathology》2020,69(4):618-630
Yellow rust is the major wheat disease in central West Asia and North Africa. Recently, severe epidemics have occurred, with major yield losses in 2010–2011 in Lebanon and Syria. We conducted an extensive field survey, with a collection of 273 samples of Puccinia striiformis f. sp. tritici, to explore the origin of these epidemics. All samples were genotyped with 20 microsatellite markers, and 54 isolates were pathotyped. The population was dominated by the PstS2 lineage, which has spread worldwide since 2000 and displays considerable pathotype diversity (10 pathotypes). The 22 multilocus genotypes (MLGs) detected corresponded to variants of the clonal lineage PstS2, but they differed from the common PstS2 genotype found in the worldwide study conducted between 1981 and 2010. No strong differentiation was observed between Lebanon and Syria. The dominant MLG in Syria was common to both countries. Nine MLGs were found exclusively in the Syrian population and four were restricted to the Lebanese population, including the dominant MLG in Lebanon. The predominant MLG-11 was found in nine pathotypes, at high frequency. The dominant pathotype in Syria was virulent against widely deployed resistance genes (Yr2, Yr6, Yr7, Yr9, Yr25, and Yr27); virulence against Yr3, Yr8, Yr17, and YrSP occurred at various frequencies, but Yr1, Yr4, Yr5, Yr10, Yr15, and Yr32 were effective against all isolates. No host effect was detected. The presence of diverse host populations consisting of landraces and elite varieties, and diverse climatic conditions may account for the unexpectedly high diversity of this clonal population. 相似文献
9.
Emna Abdellatif Monika Kałużna Patrizia Ferrante Marco Scortichini Bochra Bahri Jaap D. Janse Johan van Vaerenberg Steve Baeyen Piotr Sobiczewski Ali Rhouma 《Plant pathology》2020,69(8):1414-1425
Citrus blast and black pit caused by Pseudomonas syringae pv. syringae (Pss) is the only bacterial disease reported in Tunisian Citrus orchards. The phylogenetic relationship between Pss strains was studied based on multilocus sequence analysis (MLSA), using partial sequences of housekeeping genes rpoD, rpoB, gyrB, cts, and pfk for 14 representative Pss Citrus strains, including the reference strain LMG5496. The MLSA revealed that the studied Tunisian Citrus strains are closely related to LMG5496 and cluster in phylogroup 02. Based on the cts gene, the majority of Citrus strains clustered in clades “a” and “b”. However, five strains were placed in a newly defined clade “g”. We describe the presence of six different type III secreted effectors (T3SEs). These were found with frequencies of 100% for the effector hopAN1 and the helper hrpK1, 65% for hopT1-2, and 14% for hopN1, hopR1, and hopQ1-2. Investigation of copper resistance showed that 67% of our Pss Citrus strains from Tunisia are resistant to copper sulphate in vitro, and the copper resistance genes copABCDR were detected in 23% of the strains. Our results present new data concerning the genetic diversity and phylogeny, presence of T3SEs, and copper resistance within the Pss populations that affect Citrus in Tunisia. 相似文献
10.
Haithem Bahri Cornelia Rumpel Daniel P. Rasse Claire Chenu André Mariotti 《Soil biology & biochemistry》2006,38(7):1977-1988
Lignin transformation and decomposition products are generally considered a major source of stable soil organic matter (SOM). Nevertheless this process remains poorly understood in part because lignin is a heterogeneous biopolymer composed of several types of phenol monomers, which potentially display specific and contrasting decomposition kinetics in soils. Here, we compared the specific in situ turnover kinetics of individual lignin monomers in a Paris-basin loamy soil through natural 13C labeling of SOM generated in a series of 1-9-year chronosequences of maize monoculture (C4, δ13C −12‰) replacing wheat (C3, −27‰). Lignin monomers were released by CuO oxidation, quantified by gas chromatography (GC)/flame ionization detection (FID) and their 13C content was determined by GC coupled via a combustion interface to isotope ratio mass spectrometry (GC/C-IRMS). We calculated the proportion of C4-derived OC in lignin monomer pools by applying the isotopic mass balance equation to each lignin monomer.Individual C4-derived phenols displayed contrasting accumulation rates in soils over time, confirming the monomer-specific nature of their transformation kinetics. In proportion to total lignin phenols in soils, syringyl (S) and cinnamyl (C) phenols from maize accumulated faster than their vanillyl (V) counterparts. Consequently, the turnover kinetics of lignin-derived V-moieties may be slower than those of S and C ones. Incorporation of maize-derived carbon was faster in the aldehyde than in the acid pool for V-type units, while the opposite was observed for S-units. These in situ trends for phenol monomers and V-, S- and C-moieties were remarkably similar to the trends described in the literature with laboratory incubation or litterbag studies.None of the observed kinetics had a linear shape. Using only the extreme points of the chronosequence to calculate the kinetic parameters would result, for all the lignin monomers, in underestimating the turnover kinetics at the beginning of the kinetics and overestimating it for longer times. This observation underlines the importance of comprehensive 13C time-sequence labelling experiments such as provided at the Closeaux site, to accurately compute the kinetic parameters of SOM for the 1st years after the vegetation change. 相似文献