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1.
Septoria tritici blotch (STB), caused by Mycosphaerella graminicola has recently become one of the devastating diseases in Iran causing significant yield losses on most commercial bread and durum wheat cultivars. Iran is located in the Fertile Crescent, a region where wheat was historically domesticated; and, thus, landraces derived from this region are of considerable global interest for identification of new sources of resistance to various stresses. Here, we report on the resistance responses of 45 tetraploid wheat landraces collected from different provinces of Iran to eight M. graminicola isolates. In total 138 isolate-specific resistances were found among all interactions (n = 360). The highest number of specific resistances (30 out of 32 interactions) was found in wheat landraces collected from West Azarbaijan. In contrast, all landraces from Kordestan were highly susceptible to M. graminicola isolates and only one isolate-specific resistance was identified among 106 isolate-wheat interactions. Kermanshah landraces showed the highest resistance variation against different isolates. About 57 isolate-specific resistances were identified among 104 interactions. Ilam landraces were highly resistant to STB as 28 specific resistances were observed among 32 interactions. Markazi (n = 2) and Sistan-Baluchestan (n = 1) were susceptible to all isolates tested. Landraces from Lorestan were generally susceptible to isolates tested as 26 susceptible responses were observed out of 32 interactions. Our results indicate that landraces collected from the Fertile Crescent region may possess diverse effective resistance genes or valuable broad spectrum resistance genes, and that their identification is of interest and can be exploited in breeding programs.  相似文献   
2.
The present investigation reports the novel synthesis of CoWO4 nanoparticles@silk fiber under ultrasound irradiation. The effect of temperature, power of ultrasound irradiation and sequential dipping steps in growth of the CoWO4 particles were studied. Results show a decrease in the particles size as the temperature and power of irradiation decreased. The fibers containing CoWO4 nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity. The results show the CoWO4 nanoparticles@silk with strongest fluorescence characteristics can be obtained in this method. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy.  相似文献   
3.
Estimation of crop evapotranspiration (ETC) for certain crops such as potato is very important for irrigation planning, irrigation scheduling and irrigation systems management. The primary focus of this study was to investigate the accuracy of the adaptive neurofuzzy inference system (ANFIS) and support vector machines (SVM) for potato ETC estimation when lysimeter measurements or the complete weather data for applying the FAO method are not available. The estimates of the ANFIS and SVM models were compared with the empirical equations of Blaney–Criddle, Makkink, Turc, Priestley–Taylor, Hargreaves and Ritchie. The performances of the different SVM and ANFIS models were evaluated by comparing the corresponding values of root mean square error (RMSE), mean absolute error (MAE) and correlation coefficient (r). The drawn conclusions confirmed that the SVM and ANFIS models could provide more accurate ETC estimates than the empirical equations. Overall, the minimum RMSE (0.042 mm/day) and MAE (0.031 mm/day) values and the maximum r value (0.98) were obtained using the SVM model with mean air temperature, relative humidity, solar radiation, sunshine hours and wind speed as inputs.  相似文献   
4.
Spermatozoa concentration, ionic composition, osmolality, glucose and total protein contents of seminal plasma and sperm motility were determined in Barbus sharpeyi (Cyprinidae, Teleosotei). Spermatozoa concentration ranged from 9.77 to 20.20 × 109 spermatozoa mL?1. Osmolality (mOsmol kg?1) and ionic contents (mM L?1) of the seminal plasma were 274.5±9.0, 70.0±3.4 Na+, 28.8±0.9 K+, 101.7±3.1 Cl?, 0.9±0.1 Mg2+ and 2.1±0.1 Ca2+ respectively. Total protein and glucose were 5.3±0.2 g L?1 and 76.7±4.3 mM L?1 respectively. Sperm motility was initiated in a hypo‐osmotic condition, composed of either an ionic (KCl or NaCl) or a non‐ionic (sucrose) activation medium. Duration of sperm motility was very short: <2 min after activation in distilled water. Percentage of motile spermatozoa was significantly higher in an activation medium containing NaCl compared with that of distilled water. An activating medium containing NaCl or KCl higher than 150 mM or sucrose higher than 275 mM totally inhibited the activation of sperm motility. Immediately after sperm activation, wave(s) propagated along the flagellum, but waves were restricted to the proximal part of the flagellum (close to the head) at 1 min post activation. Studied characteristics in the present study were compared with those of other cyprinids for understanding inter‐species differences.  相似文献   
5.

Context

Conflict over land use is endemic to natural resource management given the limited availability of resources and multiple stakeholders’ interests, but there has been limited research to examine conflict from an integrative social-ecological perspective.

Objectives

We sought to determine how the potential for land use conflict—a social construct—was related (or not) to ecological systems of landscapes.

Methods

Using participatory mapping data from a regional case study in Australia, we identified the potential for land use conflict using a model that combines spatially-explicit place values with preferences for specific land uses related to development and conservation. Multiple proxies of biodiversity were used to evaluate the landscape’s ecological systems at ecosystems and species levels. Range maps were used to identify areas of high species diversity value using the conservation planning software Zonation.

Results

We spatially intersected conflict areas with landscape attributes and found the potential for conflict over conservation to be higher in coastal areas than inland areas, more likely to be located in areas with moderate vegetation cover, more concentrated in ecosystems classified as ‘No Concern’ with moderate to high native vegetation. Potential conflict over conservation was disproportionately higher in areas with higher species diversity derived from conservation modelling.

Conclusions

The social-ecological associations in conflict analysis can inform impact assessment of land use plans on biodiversity, assist development of effective approaches to reconcile conservation and other land uses, support conservation planning by identifying priorities for conflict negotiation and understanding underlying factors for conflict.
  相似文献   
6.
7.
In this study, chitosan and pentasodium tripolyphosphate (TPP)-based bilayers were fabricated on the cationized woven cotton fabrics via layer-by-layer (LBL) self-assembly technique. The initial cationic charges on cotton fabric were produced through the aminization procedure involving the covalent attachment of reactive dye to cotton fabric and subsequent reductive cleavage of the dye to free amine. Different numbers of bilayers (1, 5, and 10) consisting of chitosan/TPP have been deposited on the fabrics. The surface morphology, cationic group content, chemical surface modification, whiteness index, surface tension and antibacterial properties of the modified cotton samples were investigated using scanning electron microscopy (SEM), methylene blue test, FTIR, reflectance spectroscopy, water contact angle measurements and antibacterial test, respectively. The bacterial inhibition experiments demonstrated that the modified cotton fabric with the addition of chitosan/TPP bilayers can increase the degree of inhibition on E. coli and S. aureus bacteria. The utilized LBL method was an easy and cost-effective procedure for developing of novel antibacterial textiles with the highly attractive feature in the medical and hygienic products.  相似文献   
8.

Background:

Cutaneous leishmaniasis is one of the most important parasitic diseases in humans. In this disease, one of the responsible organisms is Leishmania major, which is transmitted by sandfly vector. There are specific differences in biochemical profiles and metabolite pathways in logarithmic and stationary phases of Leishmania parasites. In the present study, 1H NMR spectroscopy was used to examine the metabolites outliers in the logarithmic and stationary phases of promastigotes in L. major to enlighten more about the transmission mechanism in metacyclogenesis of L. major.

Methods:

Promastigote was cultured, logarithmic and stationary phases were separated by the peanut agglutinin, and cell metabolites were extracted. 1H NMR spectroscopy was applied, and outliers were analyzed using principal component analysis.

Results:

The most altered metabolites in stationary and logarithmic phases were limited to citraconic acid, isopropylmalic acid, L-leucine, ornithine, caprylic acid, capric acid, and acetic acid.

Conclusion:

1H NMR spectroscopy could play an important role in the characterization of metabolites in biochemical pathways during a metacyclogenesis process. These metabolites and their pathways can help in exploiting a transmission mechanism in metacyclogenesis, and outcoming data might be used in the metabolic network reconstruction of L. major modeling. Key Words: Leishmania major, Metabolomics, Principal component analysis  相似文献   
9.
The purpose of this research was to identify the pathogens causing root and crown rot in major pomegranate-growing areas of Iran. Infected tissue samples were collected from trees with symptoms from 49 pomegranate orchards in four provinces of Iran: Fars, Markazi, Isfahan, and Kohgiluyeh va Boyer-Ahmad. In total, 23 Phytophthora spp. isolates were obtained, which were identified as P. cryptogea species complex (12 isolates) and P. cinnamomi (11 isolates) based on morphological characters. Molecular confirmation of identification was performed by inference of phylogeny of ITS-rDNA regions, β-tubulin gene, and the mitochondrial gene cytochrome c oxidase subunit 1. The results of our phylogenetic analysis confirmed the morphological identification of P. cinnamomi isolates and placed them in Clade 7c of Phytophthora. In addition, the P. cryptogea species complex isolates, despite morphological similarities, were in fact four distinct species including P. cryptogea sensu stricto (two isolates), P. pseudocryptogea (one isolate), P. sp. kelmania (one isolate), and P. erythroseptica (six isolates). This is the first report of pomegranate root and crown rot caused by P. cinnamomi and P. cryptogea species complex.  相似文献   
10.
This study was carried out to investigate the effects of long-term cultivation and landscape position on organic carbon content and soil aggregation. Sampling sites were determined based upon land use at the end of 50 years soil use and management, cultivated/annual wheat cropping and grazed pasture, and landscape position in Chaharmahal-va-Bakhtiary province, southwest Iran. Soil samples were collected from the 0–5 cm and 5–15 cm depths in two adjacent fields that have the same slope and aspect. The soil was silty clay at the summit and footslope positions, and was a silty clay loam at the backslope. Wet-sieving analysis and aggregate-size fractionation methods were used to separate the samples into three aggregate fractions (i.e., 2–4.75, 0.25–2, and 0.053–0.25 mm). The treatments were arranged in a factorial design. Land use significantly affected the water-stable aggregate fractions, so that the wet soil stability of the macroaggregates (i.e., 2–4.75 mm) was higher in the pasture, whereas it was greater for the meso-aggregates (i.e., 0.25–2 mm) in the cultivated soils. Cultivation decreased both the wet-aggregate stability and percent of macroaggregates whereas long-term pasture enhanced aggregation. Soil organic carbon (SOC) content within aggregates and primary particles was also significantly influenced by landscape position, land use, and the depth of sampling. The SOC content was higher in clay than those in silt and sand contents. The SOC content decreased as depth increased in all fractions. In general, the highest and lowest wet-stable aggregates were observed on the footslope and backslope positions, respectively.  相似文献   
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