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A field study was conducted during 2015–2017 in order to evaluate effects of the foliar application of different sources and concentrations of zinc oxide (ZnO) on the yield and morpho-physiological characteristics of saffron. Experimental treatment included the foliar application of nano ZnO at a concentration of (3, 6, and 9 g L?1), foliar application of normal ZnO at a concentration of (3, 6, and 9 g L?1) and the control. Both types of ZnO had positive effects on the saffron yield and number of flowers, but the highest yield and flower number were obtained by the foliar application of 9 g L?1 normal ZnO followed by 6 g L?1 nano ZnO. Increasing concentrations of both fertilizers up to 3 g L?1 had no significant effect on crocin, but the crocin content significantly decreased at higher concentrations. Effects of experimental treatments were significant on all morpho-physiological traits. The maximum chlorophyll a (1.74 mg.g?1) was observed in normal ZnO at a concentration of 9 g L?1 followed by nano ZnO at a concentration of 3 g L?1. The increasing application of different types of fertilizers linearly increased the Peroxidase activity, but the highest activity of Catalase in normal ZnO and nano ZnO was measured after the foliar application at concentrations of 3 and 6 g L?1, respectively.  相似文献   
3.
Although root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 USAlthough root crops are widely cultivated in Iran, little is known about soil loss due to crop harvesting (SLCH). We assessed the annual exported soil, soil organic matter (SOM) and nutrients from 47 farms under root crops in southwestern Iran. Soil losses for garlic, potato, sugar beet, radish and beetroot were estimated as 6.27, 2.52, 2.26, 4.10 and 6.95, Mg ha?1, respectively, which on average was of the order of soil losses by water erosion in the watershed basins of Iran. Total N, P2O5 and K2O losses were estimated as 36.61, 1.10 and 31.50 kg ha?1 and their costs as 18.24, 0.74 and 19.93 US$ ha?1, respectively. For the whole country, total soil, N, P2O5, K2O and SOM losses for garlic, potato and sugar beet were estimated as 731.7 × 103, 836, 27, 476 and 14.5 × 103 Mg, respectively (radish and beetroot were excluded due to no reliable data on their planted areas). Correlation analysis showed no significant relationship between soil properties and SLCH (except soil moisture content for radish and clay content for beetroot). The findings indicated that the exported soil, SOM and nutrients were at such levels that SLCH should be considered in soil erosion studies.  相似文献   
4.
Background:CE is a zoonotic parasitic infection caused by Echinococcus granulosus worldwide and is associated with economic losses among livestock animals. EG95 is an immunogenic antigen from the E. granulosus. Lactococcus lactis has been prested as a safe vehicle for antigen delivery. The goal of this study was to design a novel L. lactis strain displaying EG95 as a vaccine delivery system. Methods:The eg95 encoding gene fragment fused to the M6 anchoring protein was cloned into the pNZ7021 vector, and L. lactis NZ9000 displaying recombinant EG95 was constructed. The expression of an approximately 32-kDa EG95 protein was confirmed by Western blotting and immunofluorescence analysis. The immune responses were evaluated in BALB/c mice immunized orally and subcutaneously with the live and killed recombinant L. lactis, respectively. Results:Total IgG level in mice immunized with heat-killed recombinant L. lactis (pNZ7021-eg95) significantly increased compared to the control group. sIgA was significantly higher in mice received live recombinant L. lactis (pNZ7021-eg95) compared to the control mice. Splenic lymphocytes from immunized mice represented the high levels of IFN-γ and the low-levels of IL-4 and IL-10. Conclusion:Our results indicate that immunization with EG95-expressing L. lactis can induce both specific humoral and cellular immune responses in mice. Key Words: Echinococcus granulosus, Lactococcus lactis, Immunization, Vaccines  相似文献   
5.
Limited information is available on biological effects of various levels of nickel (Ni) (deficiency to toxicity levels) on growth and yield of certain crops, particularly vegetables. In this sand‐culture study, we investigated the effects of four levels of Ni (0, 50, 100, and 200 μM) on growth, yield, and fruit‐quality attributes of two cucumber cultivars (Cucumis sativus L. cvs. Super Dominus and Negin) supplied with urea or NH4NO3 as nitrogen source. Addition of 50 μM Ni to the nutrient solution resulted in a significant increase of shoot and root dry‐matter yield of cv. Negin although this increase was greater in the urea‐fed plants than those fed with NH4NO3. In both cultivars, addition of 50 μM Ni increased urease activity and thereby decreased the urea concentration in the urea treatment. Addition of 100 and 200 μM Ni caused a significant decrease in root and shoot growth of cucumber although this decrease was insignificant for cv. Super Dominus in the 100 μM treatment. The highest fruit yield, total soluble solids (TSS), and fruit firmness were achieved at the 50 μM Ni treatment. Regardless of nitrogen source, Ni addition proportional to the concentration used increased leaf Ni concentration and fruit acid ascorbic concentration. The concentration of Ni required for optimum growth and yield of cucumber varied with cultivars. The level of 50 μM was sufficient for optimum growth of cv. Negin in nutrient‐solution culture while lower concentration of Ni was required for cv. Super Dominus. While the beneficial effects of sufficient levels of Ni on growth and yield of urea‐fed plants was greater than with NH4NO3‐fed plants, the toxic effects of Ni in these plants were also greater.  相似文献   
6.

Background

Non-invasive and high-throughput monitoring of drought in plants from its initiation to visible symptoms is essential to quest drought tolerant varieties. Among the existing methods, chlorophyll a fluorescence (ChlF) imaging has the potential to probe systematic changes in photosynthetic reactions; however, prerequisite of dark-adaptation limits its use for high-throughput screening.

Results

To improve the throughput monitoring of plants, we have exploited their light-adaptive strategy, and investigated possibilities of measuring ChlF transients under low ambient irradiance. We found that the ChlF transients and associated parameters of two contrasting Arabidopsis thaliana accessions, Rsch and Co, give almost similar information, when measured either after ~20 min dark-adaptation or in the presence of half of the adaptive growth-irradiance. The fluorescence parameters, effective quantum yield of PSII photochemistryPSII) and fluorescence decrease ratio (R FD) resulting from this approach enabled us to differentiate accessions that is often not possible by well-established dark-adapted fluorescence parameter maximum quantum efficiency of PSII photochemistry (F V/F M). Further, we screened ChlF transients in rosettes of well-watered and drought-stressed six A. thaliana accessions, under half of the adaptive growth-irradiance, without any prior dark-adaptation. Relative water content (RWC) in leaves was also assayed and compared to the ChlF parameters. As expected, the RWC was significantly different in drought-stressed from that in well-watered plants in all the six investigated accessions on day-10 of induced drought; the maximum reduction in the RWC was obtained for Rsch (16%), whereas the minimum reduction was for Co (~7%). Drought induced changes were reflected in several features of ChlF transients; combinatorial images obtained from pattern recognition algorithms, trained on pixels of image sequence, improved the contrast among drought-stressed accessions, and the derived images were well-correlated with their RWC.

Conclusions

We demonstrate here that ChlF transients and associated parameters measured even in the presence of low ambient irradiance preserved its features comparable to that of measured after dark-adaptation and discriminated the accessions having differential geographical origin; further, in combination with combinatorial image analysis tools, these data may be readily employed for early sensing and mapping effects of drought on plant’s physiology via easy and fully non-invasive means.
  相似文献   
7.
Several different phenotypes of the native Pramenka sheep have been developed in the Balkan region for different environmental and socio‐cultural conditions. Animals from seven West Balkan Pramenka sheep types were analysed for 15 microsatellite markers and for mitochondrial DNA (mtDNA) and the results were used to assess genetic variation within and among the types and to infer the genetic population structure of the Pramenka sheep. Mean expected heterozygosity and allelic richness over the microsatellite loci and sheep types were 0.78 and 7.9, respectively. A Bayesian statistical method for estimating hidden genetic structure suggested that a core of the largest panmictic population was formed by Serbian, Kosovan, Bosnian, Montenegrin and Albanian types, while Croatian and Macedonian types comprised two other main populations, respectively. Mitochondrial DNA analysis revealed two mtDNA haplogroups in the Pramenka sheep, B and A, with a frequency of 93.7% and 6.3%, respectively. A total of 60 mtDNA haplotypes were found in 64 animals sequenced, and the mean nucleotide and haplotypic diversities over the types were 0.013 and 0.945, respectively. Molecular analysis suggests that the West Balkan Pramenka sheep types have their origins in two distinct maternal lineages of domestic sheep and different Pramenka phenotypes tend to form few panmictic populations. The Pramenka sheep represents a valuable resource of genetic diversity in sheep.  相似文献   
8.
This paper presents the results of monitoring the shallow groundwater quality around two municipal landfill sites in the Eastern Province of Saudi Arabia. Boreholes were installed at Dhahran and Juaymah sites upstream and downstream of the landfill. Twenty water samples were collected from each borehole and analyzed for various parameters mainly for BOD, COD, TOC, NH3-N, TKN, sulphate, chloride, hardness and metals. The result of the analysis of water samples from Dhahran boreholes shows an increase in the concentration of pollutants in downstream groundwater over that observed in upstream boreholes. The average concentration of BOD5, COD and TOC in the samples obtained from the downstream borehole was found to be 6.5, 23.5, and 34.3 mg L?1, respectively. On the other hand, the mean concentration of the same parameters in upstream monitoring wells was found to be less than 2.4, 11.5, and 10.0 mg L?1, respectively. The ammonia-N and organic-N in the downstream wells were 0.37 and 0.29 mg L?1, respectively, whereas, in upstream wells they were 0.11 and 0.15 mg L?1, respectively. At Juaymah, the average concentration of BOD and TOC in groundwater samples obtained from upstream boreholes were less than 3.0 and 7.2 mg L?1, respectively, while the concentration of the same parameters in downstream well samples were above 5.0 and 35.0 mg L?1, respectively. A similar trend of increment of ammonia-N, organic-N, phosphate, sulfate and metals in downstream samples was observed. Since the water from these shallow aquifers at both places is not being used for human consumptions or for any other commercial purpose, therefore, the minor increase in pollutants concentration at downstream level is not of a great concern.  相似文献   
9.
Dietary antioxidants may provide a cost-effective strategy to promote health in obesity by targeting oxidative stress and inflammation. We recently found that the antioxidant-rich grape skin extract (GSE) also exerts a novel anti-hyperglycemic activity. This study investigated whether 3-month GSE supplementation can improve oxidative stress, inflammation, and hyperglycemia associated with a Western diet-induced obesity. Young diet-induced obese (DIO) mice were randomly divided to three treatment groups (n = 12): a standard diet (S group), a Western high fat diet (W group), and the Western diet plus GSE (2.4 g GSE/kg diet, WGSE group). By week 12, DIO mice in the WGSE group gained significantly more weight (24.6 g) than the W (20.2 g) and S groups (11.2 g); the high fat diet groups gained 80% more weight than the standard diet group. Eight of 12 mice in the W group, compared to only 1 of 12 mice in the WGSE group, had fasting blood glucose levels above 140 mg/dL. Mice in the WGSE group also had 21% lower fasting blood glucose and 17.1% lower C-reactive protein levels than mice in the W group (P < 0.05). However, the GSE supplementation did not affect oxidative stress in diet-induced obesity as determined by plasma oxygen radical absorbance capacity, glutathione peroxidase, and liver lipid peroxidation. Collectively, the results indicated a beneficial role of GSE supplementation for improving glycemic control and inflammation in diet-induced obesity.  相似文献   
10.
A simplex centroid mixture design was used to study the interactions between two chosen solvents, dichloromethane (DCM) and acetone (ACT), as organic-phase components in the formation and physicochemical characterization and cellular uptake of astaxanthin nanodispersions produced using precipitation and condensation processes. Full cubic or quadratic regression models with acceptable determination coefficients were obtained for all of the studied responses. Multiple-response optimization predicted that the organic phase with 38% (w/w) DCM and 62% (w/w) ACT yielded astaxanthin nanodispersions with the minimum particle size (106 nm), polydispersity index (0.191), and total astaxanthin loss (12.7%, w/w) and the maximum cellular uptake (2981 fmol/cell). Astaxanthin cellular uptake from the produced nanodispersions also showed a good correlation with their particle size distributions and astaxanthin trans/cis isomerization ratios. The absence of significant (p > 0.05) differences between the experimental and predicted values of the response variables confirmed the adequacy of the fitted models.  相似文献   
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