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91.
A two-year experiment was conducted in an iron(Fe)-deficient orchard with calcareous soil to find out an alternate method for soil application of Fe ethylenediamine-N,N'-bis(2-hydroxyphenylacetic acid) (Fe-EDDHA) in orange trees. Foliar sprays of Fe-EDDHA (5 g l?1, pH = 7.8), sulfuric acid (pH = 3), citric acid (5 g l?1, pH = 2.4), Fe (II) sulfate solutions (250, 500, and 750 mg Fe l?1) with their initial pH (6.5, 6.35, and 6.12) and reduced ones to pH of 3 were compared with soil applied (75 g tree?1) Fe-EDDHA and a control test. Although optimum chlorophyll content, leaf Fe concentration, fruit quantitative and qualitative attributes were resulted from soil application of Fe-EDDHA, repeated sprays of Fe-EDDHA or acidified Fe solutions created suitable results. Acidification of Fe solutions made them more effective in alleviation of leaf Fe concentration and Fe chlorosis, probably due to remobilization of inactive Fe within the plant and prevention of Fe oxidation and precipitation in foliar solutions. 相似文献
92.
Mir Ahmad Mousavi Shalmani Reza Khorassani Kazem Khavazi Mohammad Zaman 《Communications in Soil Science and Plant Analysis》2017,48(11):1247-1258
To investigate the effect of applying 15N-labeled ammonium sulfate with or without a nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) on fertilizer use efficiency and crop productivity of different wheat genotypes, a field trial was conducted at the Nuclear Agricultural Department’s farm of Iran in 2013–2014. The treatments included five wheat genotypes with different 13 C isotope discrimination and three fertilizer treatments, an unfertilized control, 15N-labeled ammonium sulfate, and 15N-labeled ammonium sulfate with DMPP in three replications. Soil samples were taken after 2, 4, and 6 weeks after sowing and also at harvest time. Results from 15N experiment showed that DMPP delayed nitrification of ammonium for 42 days. Genotypes with lower discrimination index had greater uptake of ammonium ions which led to increase crop yield and nitrogen fertilizer use efficiency. The results also suggested that the use of DMPP may not be beneficial in some fast growing wheat genotypes. 相似文献
93.
Reza Ghanbarpour Nasrin Askari Masoud Ghorbanpour Yahya Tahamtan Khoobyar Mashayekhi Narjes Afsharipour Nasim Darijani 《Tropical animal health and production》2017,49(3):591-597
The aim of the present study was to determine the analysis of virulence genes and antimicrobial profile of diarrheagenic Escherichia coli isolated from diseased lambs. Two hundred ninety E. coli isolates were recovered from 300 rectal swabs of diarrheic lambs and were confirmed by biochemical tests. The pathotype determination was done according to the presence of genes including f5, f41, LTI, STI, bfp, ipaH, stx 1 , stx 2 , eae, ehlyA, cnf 1 , cnf 2 , cdIII, cdIV, and f17 by PCR method. Sixty-six isolates (23.72%) possessed the STI gene and categorized into entrotoxigenic E. coli (ETEC). Nine isolates (3.1%) and five isolates (1.72%) were positive for the cnf1 and cnf2 genes which categorized into necrotoxic E. coli (NTEC). Hundred and seventeen isolates (40.34%) harbored stx 1 and/or stx 2 and classified as Shiga toxin-producing E. coli (STEC). Thirteen isolates (4.48%) were assigned to atypical entropathogenic E. coli (aEPEC) and possessed eae gene. Two isolates (0.68%) were positive for ipaH gene and were assigned to entroinvasive E. coli (EIEC). Statistical analysis showed a specific association between eae gene and STEC pathotype (P?<?0.0001). The most prevalent resistance was observed against lincomycin (96.5%) and the lowest resistance was against kanamycine (56.02%), respectively. The high prevalence of STEC and ETEC indicates that diarrheic lambs represent an important reservoir for humans. ETEC may play an important role for frequent occurrence of diarrhea in lambs observed in this region. Due to high antibiotic resistance, appropriate control should be implemented in veterinary medicine to curb the development of novel resistant isolates. 相似文献
94.
95.
Jalal Pourahmad Mohammad Reza Eskandari Rashin Shakibaei Mohammad Kamalinejad 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):83-89
Mango (Mangifera indica L.) and their components are commonly used in folk medicine for many curative effects. The protective
effects of different concentrations of aqueous extract of Mangifera indica L. fruit (Mango Extract) (20, 50 and 100 μg/ml)
and also gallic acid (100 μM) as a pure compound in the extract were examined against oxidative stress toxicity induced by
cumene hydroperoxide (CHP) in isolated rat hepatocytes. The extracts and gallic acid (100 μM) protected the hepatocyte against
all oxidative stress markers including cell lysis, ROS generation, lipid peroxidation, glutathione depletion, mitochondrial
membrane potential decrease, lysosomal membrane oxidative damage and cellular proteolysis. Mango Extracts (20, 50 and 100 μg/ml)
were more effective than gallic acid (100 μM) in protecting hepatocytes against CHP induced lipid peroxidation. On the other
hand gallic acid (100 μM) acted more effective than Mango Extracts (20, 50 and 100 μg/ml) at preventing lysosomal membrane
damage. In addition H2O2 scavenging effect of all extracts were determined in hepatocytes and compared with gallic acid (100 μM). There were no significance
differences (P<0.05) between all plant extracts and gallic acid (100 μM) in H2O2 scavenging activity. These results suggest a hepatoprotective role for Mango Extract against liver injury associated with
oxidative stress. 相似文献
96.
97.
Taste disturbances following consumption of pine nuts, referred to as "pine mouth", have been reported by consumers in the United States and Europe. Nuts of Pinus armandii have been associated with pine mouth, and a diagnostic index (DI) measuring the content of Δ5-unsaturated fatty acids relative to that of their fatty acid precursors has been proposed for identifying nuts from this species. A 100 m SLB-IL 111 GC column was used to improve fatty acid separations, and 45 pine nut samples were analyzed, including pine mouth-associated samples. This study examined the use of a DI for the identification of mixtures of pine nut species and showed the limitation of morphological characteristics for species identification. DI values for many commercial samples did not match those of known reference species, indicating that the majority of pine nuts collected in the U.S. market, including those associated with pine mouth, are mixtures of nuts from different Pinus species. 相似文献
98.
Saeid Amiri Mohammad Jafari Jozani Reza Modarres 《Journal of Agricultural, Biological & Environmental Statistics》2014,19(1):1-17
Ranked set sampling is a sampling approach that could lead to improved statistical inference when the actual measurement of the variable of interest is difficult or expensive to obtain but sampling units can be easily ordered by some means without actual quantification. In this paper, we consider the problem of bootstrapping an unbalanced ranked set sample (URSS) where the number of observations from each artificially created stratum can be unequal. We discuss resampling a URSS through transforming it into a balanced RSS and extending the existing algorithms. We propose two methods that are designed to obtain resamples from the given URSS. Algorithms are provided and several properties, including asymptotic normality of estimates, are discussed. The proposed methods are compared with the parametric bootstrap using Monte Carlo simulations for the problem of testing a hypothesis about the population mean. 相似文献
99.
Tadayon K Forbes K Soleimani D Pajoohi RA Marhmati B Javidi J Keshavarz R Soleimani K Shakibamehr A Taheri MM Pour SD Mosavari N 《Veterinary microbiology》2011,151(1-2):192-199
In 1931 Carpantier reported bovine TB (BTB) in Iranian cattle. Some eighty years on with a national test-and-slaughter programme in place for over four decades, the efforts to vanquish Mycobacterium bovis (M. bovis) infection in cattle have been in vain as the vast majority of the 30 Iranian provinces still have reports of BTB in their cattle herds every year. This paper reviews the present epidemiology of BTB in Iran and in the region and evaluates the success of government policy in controlling this disease. 相似文献
100.
Ali Shabani Ali Reza Sepaskhah Ali Akbar Kamgar-Haghighi 《Archives of Agronomy and Soil Science》2013,59(7):951-969
The inadequacy of most models to simulate crop growth and yield is due to complexity, difficulty to understand, and lack of input data. Therefore, several simple crop growth models are presented to reduce these failures. In this investigation, yield and aboveground dry matter (DMabove) of rapeseed were simulated by two logistic growth models that were based on days after planting (DAP) and growing degree days (GDD) under water salinity and deficit irrigation, in a 2-year experiment. Data of first and second year were used for calibration and validation of the model, respectively. The coefficients of logistic function were determined as a function of irrigation water salinity and sum of applied water and rainfall in spring of the first year. Results indicated that logistic function based on GDD-predicted DMabove during growing season more accurately than logistic function based on DAP. Furthermore, seed yield of rapeseed was estimated based on harvest index with a good accuracy. Therefore, logistic function based on GDD that is based on the cumulative heat units can be used for different weather conditions and planting dates to determine rapeseed DMabove and yield under water salinity and deficit irrigation. 相似文献