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51.
In order to study the effect of plant growth promoting rhizobacteria (PGPR), Azolla compost and Azolla biochar on some soil quality indicators and rosemary growth, a greenhouse experiment was conducted in a completely randomized design with six replications. Treatments consisted of T1 (control), T2 (1% Azolla compost), T3 (1% Azolla biochar), T4 (PGPR (P. fluorescens), T5 (1% compost + PGPR) and T6 (1% biochar + PGPR). Rosemary growth parameters and nutrients concentration increased in all treatments compared to control. Treatments increased soil nutrient concentrations, soil microbial respiration (SMR) and microbial biomass C (MBC) but decreased soil metabolic quotient (qCO2) compared to control treatment. A significant enhancement in rosemary growth occurred due to the improved soil quality as a result of organic fertilizers application, particularly by co-application of P. fluorescens and compost or biochar of Azolla.  相似文献   
52.
Atmospheric pollution is an important concern in urban environments.The impact of urban pollution on the physiological,biochemical and anatomical properties of leaves of oriental plane(Platanus orientalis L.)was studied.The leaves were collected from an urban site(Tehran,Iran)and a non-urban forest park(Chitgar Forest Park).Anatomical(stomata,parenchyma,and cuticle)and physiological(chlorophyll content,enzyme activities)properties were analyzed.The concentrations of Cd(cadmium),Pb(lead),Ni(nickel),and Cr(chromium)in leaves were significantly higher and Zn(zinc)lower at the urban site relative to the forest park.Chlorophyll a,total chlorophyll,and carotenoid content in leaves of the urban site were significantly less than those of the forest park,but there was no significant difference in chlorophyll b.In addition,the activities of superoxide dismutase,catalase,ascorbate peroxidase,and guaiacol peroxidase in urban leaves were significantly higher than in the leaves of the forest park.In the urban area,leaves experienced a significant decrease in leaf surface area,stomata density,stomata pore area,epidermis,and spongy mesophyll thickness,but a significant increase in cuticle and palisade thicknesses relative to forest park leaves.The increase in enzyme activities may indicate that the trees are attempting to cope with increased reactive oxygen species(ROS)because of pollution-induced stress.Our study suggests that oriental plane trees alter their physiological and anatomical properties when living in a polluted urban environment.  相似文献   
53.
This study was conducted to evaluate the immunostimulating activity and growth promoting of diets supplemented with different rations of soluble and insoluble linseed fibre to Rhamdia quelen under hypoxia‐induced acute stress. For this reason, soluble and insoluble fractions of linseed fibre were concentrated separately and combined into four ratios (1:0.5; 1:1; 1:2 and 1:4), which were added to the diets of silver catfish (6.43 ± 0.12 g) and evaluated in a biological assay, along with a control diet (without addition of linseed fibre). After being fed the experimental diets for 45 days, specimens of silver catfish were submitted to hypoxia‐induced acute stress. They were kept out of water for 60 s. Immediately afterwards, blood and cutaneous mucus were collected for subsequent determination of immunological indicators and stress. After stress, the fish were weighed and measured for performance parameter calculation. The experimental design was completely randomized with five treatments and four replications. The data underwent analysis of variance and the means were compared by Tukey's test (p < .05). The fish fed diets containing the 1:2 and 1:4 soluble:insoluble fibre ratios, showed higher total protein content, globulin, plasma alkaline phosphatase activity, and performance in addition to higher mucoprotein content in the cutaneous mucus of the fish. Regardless of their ratio in the diet, linseed fibre provided higher plasma levels of total immunoglobulins and reduction in cortisol levels. The 1:1, 1:2 and 1:4 diets led to higher levels of total immunoglobulins and alkaline phosphatase activity in cutaneous mucus. The results indicate that linseed fibre has a stress‐ reduction, immunostimulant and a growth promoter effect on silver catfish. The 1:2 or 1:4 soluble: insoluble fibre ratios provided greater stimulation of the target immunological indicators and performance.  相似文献   
54.
This study was conducted with the objective of evaluating the combination of different ratios of soluble and insoluble linseed fibre for silver catfish (Rhamdia quelen). For this, the soluble and insoluble fractions were concentrated separately and combined in four ratios (1:0.5, 1:1, 1:2, 1:4), which were added to silver catfish diets and evaluated in a bioassay. After 45 days of receiving the experimental diets, the animals were submitted to biometry to collect data and tissues. The experimental design was completely randomized, with five treatments and four replications and the means were compared by Tukey's test (p < .05). Diets 1:2 and 1:4 provided higher weight gain, specific growth rate and crude protein deposition to the fish, whereas only the 1:4 diet reflected higher crude body protein. The 1:0.5 diet altered the trypsin activity in the intestine, and, together with the 1:4 diet, it provided a higher intestinal villi height. Body yield, somatic and digestive parameters, chymotrypsin activity and glucose, glycogen and liver protein were not altered, regardless of the experimental diets. In conclusion, the results indicate that linseed fibre acts effectively as a growth promoter in silver catfish diets, with the use of 1:2 and 1:4 ratios optimizing its prebiotic action.  相似文献   
55.
Mortality of the short-neck clam Ruditapes philippinarum exposed to the toxic dinoflagellate Heterocapsa circularisquama was studied under controlled conditions to clarify the mechanisms of recurrent mass deaths of clams occurring in western Japanese coastal areas. One-week mortality tests, involving three water temperatures, six H. circularisquama concentrations, and two clam body sizes, showed a significant increase in mortality with increasing temperature, H. circularisquama concentration, exposure duration, and body size (ANOVA, P < 0.01). Clam death was observed at concentrations as low as 50 cells/ml and temperatures as low as 15°C. Prior to death, clams showed an extreme retraction of their mantle edge and siphon, along with recurrent vomiting behavior before initiating a closure reaction followed by paralysis then death. Gills of paralyzed clams showed an important uptake of dye, implying gill damage. This study is the first laboratory evidence of bivalve mortality induced by H. circularisquama at low concentrations and low temperature, and the first report of differential effects according to the body size of bivalves.  相似文献   
56.
The yield of sugar beet depends mainly on the effective protection to a number of pests and diseases affecting the crop. In the absence of actual methods of management, as in the case of viral diseases, the availability of genetic resistance sometimes allows the survival of the crop in the affected areas. Integration of molecular markers in conventional breeding procedures has provided a reliable means for improving the efficiency of selection methods. The present review summarizes the evolution, thanks to the application of molecular techniques, of traditional breeding for resistance to some biotic stresses in sub-arid environments.  相似文献   
57.
Journal of Plant Diseases and Protection - In the central and south eastern provinces of Iran, alfalfa plants showing phytoplasma diseases-like symptoms categorized into three major types, namely...  相似文献   
58.
The goal of the present work was to test if there is genetic variability between precocious and superprecocious cycle maize genotypes in terms of grain productivity and energy profile. Data from two separate experiments were used. An experiment was conducted with 36 precocious cycle genotypes and another experiment was conducted with 22 superprecocious cycle genotypes. The following variables were measured: grain productivity (PROD), ethereal extract (EE), starch (ST), amylose (AML), and nitrogen-corrected apparent metabolizable energy (AMEn). For all variables, basic statistics and analysis of variance was performed. For each experiment, the genotypic correlation matrix was calculated and the multicollinearity was evaluated. Then, the Mahalanobis generalized distance matrix was calculated, the clustering of the genotypes was performed and the averages of the groups formed were compared, separately for each experiment. There was genetic divergence between precocious genotypes, as well as between superprecocious genotypes, especially in terms of grain PROD, EE concentration, and AML concentration. Groups of more productive genotypes presented lower EE and higher AML grain concentrations. The results of the present study indicated that it is possible to plan crossings between groups of genotypes in terms of PROD, EE and AML, with the goal of maximizing heterosis.  相似文献   
59.
Background:Bispecific antibodies represent an important class of mAbs, with great therapeutic potentials due to their ability to target simultaneously two distinct epitopes. The generation of functional bispecific antibodies with the highest possible yields is particularly critical for the production of these compounds on industrial scales. Anti- CD3 × CD19 bsAb is a bispecific T-cell engager (BiTE) currently used for treating ALL. Herein, we have tried to optimize the expression level of this antibody in mammalian hosts. Methods:WPRE sequence was incorporated at the 3’ end of the expression cassette. This modification resulted in a notable about two-fold increase in the expression of the bsAb in the Expi293 cell line. Results & Conclusion:Follow-up flow cytometry analysis demonstrated the binding properties of the produced antibody at acceptable levels, and in vitro bioactivity assays showed that this product is potent enough for targeting and destroying CD19-positive cells. Our findings show that WPRE enhances the expression of this type of bispecific mAbs in HEK-293 family cell lines. This approach can be used in biopharma industry for the mass production of anti-CD3 × CD19 bispecific antibody. Key Words: Acute lymphoblastic leukemia, Bispecific antibodies, Monoclonal antibody  相似文献   
60.
The occurrence of mycobacteriosis caused by Mycobacterium marinum in a commercial breeding farm of bullfrogs (Rana catesbeiana) in Rio de Janeiro, Brazil is described. Ten animals presented skin lesions on the head and extremities. These and 38 other asymptomatic adult animals from various tanks were killed and at necropsy disseminated granulomatous lesions were observed in the 10 clinically affected animals and in 16 (42.1%) of the asymptomatic frogs. Acid-fast bacilli were observed in all smears of the 10 symptomatic frogs and in all but one from the 16 asymptomatic animals with visceral lesions. Ten samples from the 25 positive animals were randomly selected for culture which yielded four isolates of fast-growing (<7 days) mycobacteria. Those purified isolates were characterised by biochemical traditional means as M. marinum. Identification of the strains was confirmed using reverse-phase high-performance liquid chromatography and a polymerase chain reaction (PCR) restriction enzyme analysis assay. It is suggested that M. marinum is an important agent of granulomatous disease in bullfrogs and that infected animals, even when asymptomatic, could act as reservoirs spreading the disease and contaminating other frogs in the farm.  相似文献   
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