Characterization of virulence reactions for Heterodera avenae populations from two localities in Algeria     

Fatima Haddadi  Aïssa Mokabli  Richard W. Smiley 《Phytoparasitica》2013,41(4):449-456

Heterodera avenae is widely distributed in areas where most cereal crops are produced in Algeria. However, the virulence of the Algerian populations of this nematode on individual cereal species and cultivars has not been well documented. The virulence of H. avenae populations from Tiaret and from Oued Smar were tested under natural outdoor conditions and in an in vitro test to determine reactions of nine barley, oat and wheat cultivars selected from the International differential assortment for identifying pathotypes of H. avenae. All nine cereal differentials expressed the same reactions to both populations. The nematodes reproduced well on the barley cultivar ‘Emir’ and the wheat cultivar ‘Capa’. Resistant entries included the barley cultivars ‘Siri’, ‘Ortolan’ and ‘Morocco’, the oat cultivars ‘Nidar II’ and ‘A. sterilis I.376’, and the wheat cultivars ‘Loros’ and ‘AUS10894’. This matrix of reactions indicated that H. avenae populations from both locations were characterized as H. avenae Group 1 pathotypes but did not conclusively distinguish among pathotypes Ha21, Ha31 or Ha81. The Cre1 gene was identified as a potentially valuable source of resistance when developing wheat cultivars intended for release into these localities.  相似文献   

Impact of Exogenous Application of Salicylic Acid on Growth,Water Status And Antioxidant Enzyme Activity of Strawberry Plants (Fragaria vesca L.) Under Salt Stress Conditions     

Lamnai  Kamal  Anaya  Fatima  Fghire  Rachid  Zine  Hamza  Wahbi  Said  Loutfi  Kenza 《Gesunde Pflanzen》2021,73(4):465-478

Irrigation with saline water can act as an alternate water resource and thus plays an important role in saving freshwater resources as well as promoting agriculture. Furthermore, salinity stress is considered one of the major abiotic stress factors, which strongly reduces crop productivity. In this context, the present work was conducted to examine the effect of exogenous salicylic acid (SA) application on salt stress tolerance of strawberry plants. For this purpose, strawberry plants (Fragaria vesca L.), three months old, were treated with three SA concentrations (0?mM, 0.25?mM and 0.5?mM), then subjected to 80?mM NaCl or not. After five weeks of treatment, growth responses, water status, photochemical efficiency and oxidative stress indicators were measured. The obtained results showed that irrigation with saline water negatively affected the growth parameters, the leaf water potential (LWP), the relative water content (RWC), the stomatal conductance (gs) and photochemical efficiency (Fv/Fm). While, the total protein content, the electrolyte leakage (EL), the malondialdehyde (MDA) and the hydrogen peroxide (H₂O₂) contents were increased in stressed plants compared to unstressed ones. Salt stress also leads to the activation of the antioxidant enzymes. However, the exogenous application of SA under salt stress conditions reduced the H₂O₂ accumulation, the electrolyte leakage and the MDA content. It has also improved the growth parameters, the LWP, the RWC, the gs, the Fv/Fm, the protein content and the antioxidant enzyme activities (POD, CAT and SOD) in the treated plants compared to those without SA application. Therefore, the beneficial effect of 0.25?mM SA on Fragaria vesca L. salinity tolerance may provide some practical basis for strawberry cultivation under saline conditions.

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Seed dimorphism,chromosome number and karyotype of the amphicarpic species <Emphasis Type="Italic">Trifolium argentinense</Emphasis> Speg.     

Ionara Fatima Conterato  Maria Teresa Schifino-Wittmann  Miguel Dall′Agnol 《Genetic Resources and Crop Evolution》2010,57(5):727-731

Amphicarpy, a specialized form of dimorphism where fruits and seeds are formed in underground and aerial flowers, has been reported in only ca. 50 flowering plants. Trifolium argentinense Speg. is an amphicarpic legume species that occurs in native pastures of Southern Brazil. Data on seed dimorphism, chromosome number and karyotype of the species are presented for the first time. T. argentinense is diploid, with 2n = 2x = 16. Chromosome size range from ca. 2.8 to 1.6 μm, the karyotypic formula is 3 metacentric + 1 satellite-bearing metacentric + 3 acrocentric + 1 subacrocentric and a TCL (total complement length) of 18.10 μm. All the subterranean, but around 70% of the aerial legumes formed seeds. Subterranean seeds were larger and heavier (2.1 mm and 0.0029 g, respectively) than the aerial ones (1.8 mm and 0.0016 g, respectively). As a follow up to this work, we plan to characterize aerial and subterranean-seed-derived plants regarding aspects such as growing rate, height, leaf size and forage production, as well as to determine the exact mode of reproduction of T. argentinense by pollination experiments and the use of molecular markers.  相似文献   

Type, density, and location of immune cells within human colorectal tumors predict clinical outcome     

Galon J  Costes A  Sanchez-Cabo F  Kirilovsky A  Mlecnik B  Lagorce-Pagès C  Tosolini M  Camus M  Berger A  Wind P  Zinzindohoué F  Bruneval P  Cugnenc PH  Trajanoski Z  Fridman WH  Pagès F 《Science (New York, N.Y.)》2006,313(5795):1960-1964

The role of the adaptive immune response in controlling the growth and recurrence of human tumors has been controversial. We characterized the tumor-infiltrating immune cells in large cohorts of human colorectal cancers by gene expression profiling and in situ immunohistochemical staining. Collectively, the immunological data (the type, density, and location of immune cells within the tumor samples) were found to be a better predictor of patient survival than the histopathological methods currently used to stage colorectal cancer. The results were validated in two additional patient populations. These data support the hypothesis that the adaptive immune response influences the behavior of human tumors. In situ analysis of tumor-infiltrating immune cells may therefore be a valuable prognostic tool in the treatment of colorectal cancer and possibly other malignancies.  相似文献   

Ecological populations of bacteria act as socially cohesive units of antibiotic production and resistance     

OX Cordero  H Wildschutte  B Kirkup  S Proehl  L Ngo  F Hussain  F Le Roux  T Mincer  MF Polz 《Science (New York, N.Y.)》2012,337(6099):1228-1231

In animals and plants, social structure can reduce conflict within populations and bias aggression toward competing populations; however, for bacteria in the wild it remains unknown whether such population-level organization exists. Here, we show that environmental bacteria are organized into socially cohesive units in which antagonism occurs between rather than within ecologically defined populations. By screening approximately 35,000 possible mutual interactions among Vibrionaceae isolates from the ocean, we show that genotypic clusters known to have cohesive habitat association also act as units in terms of antibiotic production and resistance. Genetic analyses show that within populations, broad-range antibiotics are produced by few genotypes, whereas all others are resistant, suggesting cooperation between conspecifics. Natural antibiotics may thus mediate competition between populations rather than solely increase the success of individuals.  相似文献   

Biodiversity conservation in human-modified Amazonian forest landscapes     

Carlos A. Peres  Toby A. Gardner  Jansen Zuanon  Alexander C. Lees  Fatima M.S. Moreira 《Biological conservation》2010,143(10):2314-3276

Amazonia (sensu lato) is by far the largest tropical forest region, but has succumbed to the highest absolute rates of tropical deforestation and forest degradation, driven by rapid frontier expansion, road-building, and spontaneous or government-subsidized migration. The large area-through-time and paleo-climatic stability of Amazonian forests may help explain the high regional to local scale plant and animal species diversity of true forest specialists and high ecological sensitivity to contemporary land-use change. We describe the prevailing forms of anthropogenic disturbance that affect forest organisms in the context of the geographic and evolutionary background that has shaped the degree to which forest species may be resilient to environmental change. The fate of Amazonian biodiversity will partly depend upon the interaction between land-use and climate change, and the extent to which seasonally-dry forests can retain immunity against catastrophic recurrent wildfires. This review illustrates the importance of considering interactions between different forms of forest disturbance to develop effective conservation policy. We conclude with some considerations of the policy agenda necessary to protect forest cover and forest biodiversity at a meaningful scale across the Amazonian biome.  相似文献   

Intra-specific Variation for Salt Tolerance in Linseed (Linum usitatissimum L.)     

M. Ashraf  H. Fatima 《Journal of Agronomy and Crop Science》1994,173(3-4):193-203

Thirty-six accessions of linseed ( Linum usitatissimum L.) were screened for salt tolerance at the seedling stage after 2 weeks growth in solution culture salinized with 150mol m⁻³ NaCL Considerable variation in salt tolerance was observed in this set of germplasm. Two salt-tolerant accessions, T-5(69-S9)B and LS-2 and two salt-sensitive accessions P-70 and Aver-Rer-Seic, selected at the seedling stage, were grown to maturity in sand culture salinized with 0 (control), 70, 140, and 210 mol m⁻³ NaCl. Both the salt-tolerant accessions exceeded the two salt-sensitive accessions in biomass production, seed yield, and yield components, but the accessions did not differ significantly in seed oil content in the salt treatments. The tolerant accessions accumulated greater amounts of Na⁺ in the shoots and less in the roots compared with the salt-sensitive accessions. The shoot K⁺, K: Na ratios, and K⁺ versus Na⁺ selectivity were lower in the salt-tolerant accessions compared with the salt-sensitive accessions; the reverse was true for their roots. Contributions of Na⁺ and Ca²⁺ to osmotic adjustment were much higher in the two salt-tolerant accessions than in the salt-sensitive ones.
It has been established that there is a great deal of variation for salt tolerance in linseed. The degree of salt tolerance of this crop does not vary during ontogeny. The physiological basis of salt tolerance of this species appears to be associated with the inclusion of Na⁺ in the shoots.  相似文献   

Wastes to be the source of nutrients and energy to mitigate climate change and ensure future sustainability: options and strategies     

Mukhtar Ahmed  Shakeel Ahmad  Muhammad Tariq  Zartash Fatima  Zohra Aslam  Muhammad Ali Raza 《Journal of plant nutrition》2020,43(6):896-920

Abstract

Waste production is associated with human inhabitation and its rate is increasing over time. Globally, the major proportion of waste is disposed of through landfilling and open dumping, which is environmentally unsafe due to emission of greenhouse gases (GHGs). Thus, in order to avoid emission of GHGs from wastes it is important to use techniques that can convert wastes to energy/nutrients on eco-friendly economical way. Furthermore, quantification of the impacts of these waste management techniques on ecosystem is also needed through the application of tools like modeling, remote sensing, geographical information system (GIS), Unmanned Aerial Vehicles (UAVs) and life cycle assessments (LCA). Thus, this review was conducted by considering focus on potential of nutrient and energy recovery techniques from various types of wastes and approaches to enhance the efficiency of the process. The outcomes depicted that the aerobic and anaerobic digestion is suitable to deal with biodegradable and organic fraction of the waste, but anaerobic digestion seem to be more sustainable waste management techniques. Additionally, the review covers the techniques to drive energy and recover nutrient from non-biodegradable proportion. Different modern analytical tools; such as remote sensing, GIS and simple/dynamic models could be useful tool to help in the decision-making processes for waste managements. These tools can help us to design integrated solid waste management processes. Finally, we suggest that LCA should be considered to determine the environmental load of material/product from its production to final disposal (from cradle to grave).  相似文献   

Effects of plant growth regulators and light intensity on the micropropagation of date palm (Phoenix dactylifera L.) cv. Mejhoul     

Reda Meziani  Fatima Jaiti  Mouaad Amine Mazri  Mohamed Anjarne  Mustapha Ait Chitt  Jamal El Fadile  Chakib Alem 《Journal of Crop Science and Biotechnology》2015,18(5):325-331

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Sero-molecular survey and risk factors of equine piroplasmosis in horses in Spain     

Eliazar Camino  Aranzazu Buendia  Abel Dorrego  Pilar Pozo  Lucía de Juan  Lucas Dominguez  Fatima Cruz-Lopez 《Equine veterinary journal》2021,53(4):771-779

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