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51.
Nutrient deficiency may be a reason for citrus decline in many countries. In the current investigation, soil and leaf samples of 63 Washington Navel orange orchards in arid lands of southern Iran (Darab region) were analyzed to study the nutritional status of orange orchards and to find relationships between soil properties and nutrients content of soils and orange leaves. The soils differed widely in clay content (3–37%), pH value (7.04–7.95), calcium carbonate equivalent (18–86%), and organic matter content (0.3–12%). These soils represented a wide range of plant nutrients concentration. Majority of the studied soils had sufficient concentrations of all nutrients (except Fe). Results indicated that pH, organic matter, clay, and calcium carbonate contents are the most important characteristics that control the soil nutrients availability. The mean contents of N, K, P, Fe, Mn, Zn, and Cu in leaves were 2.59, 0.84, and 0.14% and 66, 44, 17, and 12?mg?kg?1, respectively. Most orchards showed K, Fe, and Zn deficiencies. We found no relationships between nutrients content in leaf and soil (except for K, Mn, and Zn); and this indicated that soil analysis may not be a reliable method for most nutrient deficiency diagnosis.  相似文献   
52.
In the present research, a method of assessing relative compatibility rating of single and binary mixtures of walnut green shell, cochineal, and weld natural dyes on aluminum pre-mordanted woolen yarns was proposed, where a proportion of the calculated diffusion coefficients of dyes was postulated. To calculate the diffusion coefficient values, the uptake behavior of dyes was derived as the K/S and the exhaustion curves by dyeing the woolen yarn samples with the individual dye as well as with the mixtures of dyes obtained from practical conditions of dyeing. A typical method was employed to dye the samples at two temperatures of 80 and 95 oC. The method proposed for determination of the compatibility of dyes was more verified at higher temperature, that is, 95 oC, against a conventional method of solution analysis. The results of compatibility showed that the selected binary mixtures of cochineal-weld have an excellent compatibility. The other mixtures, that is, walnut green shell-cochineal and walnut green shell-weld showed weak-moderate and very weak compatibility, respectively.  相似文献   
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In this study, botanicals extracted from two the species of family Scrophulariaceae, Verbascum cheiranthifolium Boiss and Verbascum speciosum Schard, were examined for their effect on mortality and progeny production against adults of Sitophilus oryzae (L.). The plant extracts were applied at five dose rates, which 0.25, 0.5, 1.0, 2.0 and 3% (w/v). Adults of S. oryzae was exposed to the treated wheat at 25 degrees C and 65% RH and mortality was assessed after 24 h, 48 h, 7 day, 14 day and 21 day of exposure. Then all adults were removed and the treated substrate remained at the same conditions for an additional 45 day after this interval, the commodity was checked for progeny production. In use two extracts the mortality of adults increased with the increase of dose and exposure interval so that; mortality was 100% after 21 days of exposure at the highest dose rate. Results indicated that applied of V. cheiranthifolium extract was more effective than V. speciosum against adult insects. Interestingly, in two cases complete suppression (100% reduction) of the progeny production (F1) was observed in the treated wheat than in control even in the lowest dose rate. Therefore, our results indicate that these medicinal plants can be used for protection of stored grain from infestations of stored-product insect pests.  相似文献   
55.
This research was aimed to investigate the prevalence and clinical impact of occult HBV infection in thalassemic patients with chronic HCV infection. In this cross-sectional study we have totally examined 60 patients suffering HBV and HCV infections by PCR and RT-PCR methods, respectively, in Kerman province of Iran. ELISA technique (RADIM, Italy) was used to detect anti-HBc, anti-HBs and HBsAg. The serum level of liver enzymes (SGOT, SGPT, DB, TB and ALK) were analyzed in the HCV infected patients (MAN, IRAN). Statistical analyses performed using t-test and Chi-square. We found that 27 cases (out of 60) were infected by HCV but HBV-DNA was not seen in HCV infected patients. Present findings also showed that none of samples were HBsAg positive but 9 (33%) (out of 27) HCV-RNA positive patients were anti-HBc positive and 11 (40.7%) were positive for anti-HBs. We found that SGOT, SGPT, DB, TB and ALK are above normal in 27 (100%), 19(70.3%), 12(44.5%), 15 (55.5%) and 15 (55.5%) RNA-HCV positive patients, respectively. The prevalence of hepatitis C infection is very high in thalassemic patients and based on other studies our results showed that the prevalence of HCV infection in Kerman is more than other provinces of Iran. In contrast with other studies HBV-DNA in these patients could not be detected, hence, it seems that occult HBV infection isn't frequent in Iranian thalassemic patients who suffering from chronic HCV infection.  相似文献   
56.
Eurasian Soil Science - Arid and semiarid soils of southern Iran may fix a large content of applied potassium (K), but the fixed K may be gradually supplied to plants. Sixteen representative soils...  相似文献   
57.
ABSTRACT

The effects of combined infrared-vacuum drying parameters, including infrared power (300–400 W), pressure (5–25 kPa) and time (0–140 min) on the drying kinetics of grapefruit slices were investigated. Both the infrared lamp power and vacuum pressure influenced the drying time of grapefruit slices. The regression results showed that the quadratic model satisfactorily described the drying behavior with highest R and lowest SE values. The effective moisture diffusivity increases as power increases and range between 5.83 × 10–10 and 2.13 × 10–9 m2/s. The color scale parameters, including redness (a*), yellowness (b*) and lightness (L*) values of dried grapefruit slices increased during drying. The rise in infrared power has a negative effect on the color change intensity (?E) and with increasing in infrared radiation power it was increased. Different kinetic models were used to fit the experimental data and the results revealed that the power model was the most suitable to describe the ?E.  相似文献   
58.
The effects of super absorbent polymers (SAPs) on growth characteristics and seedlings survival of Artemisia sieberi (under two soil textures, three irrigation levels and seven hydrogel compositions with three replications) were investigated. The studied traits were shoot height, shoot dry weight, root dry weight, ratio of root/shoot, root length, root perimeter, root area and root volume. SAPs successfully enhanced growth capability of A. sieberi in two soil textures compared to the controls. Ideally, 5 g kg?1 Aquasorb? (SNF Company, France) with 100% irrigation and 10 g kg?1 Stockosorb® (Evonik Corporation, Germany) with 75% irrigation in a sandy loam texture and 10 g kg?1 Boloorab A? (Boloorab Company, Iran) with 75% irrigation in a loamy texture significantly affected all traits, resulting in 100% survival for A. sieberi seedlings. Aquasorb? and Stockosorb® showed the best results in the sandy loam texture and preferable outputs were obtained by Boloorab A? application in the loamy texture. In other words, because of the basic differentiation among soils in terms of mineralogy, temperature and moisture content, different SAPs should be applied. Production of dense root network and root aggregation stimulated by SAPs increased root contact with moisture. Therefore, improving the growth and survival of the plants is accessible using SAPs under water stress condition.  相似文献   
59.
60.
ABSTRACT

Recently, the use of biochars for stabilization of soil heavy metals has been expanded due to their adsorption characteristics, low cost and carbon storage potential. A factorial experiment was performed to investigate the effects of two plant residue biochars (licorice root pulp and rice husk biochar each applied at 2.5% (w/w)) produced at two temperatures (350 and 550 °C), and three Ni application rates (0, 150 and 300 mg Ni kg?1) on bioavailability and chemical fractions of Ni in a calcareous soil after spinach cultivation. Application of all the biochars significantly reduced Ni bioavailability factor (5–15%) and spinach Ni concentration (54–77%) in Ni-treated soil. The biochars produced at 550 °C were more effective at reducing Ni mobility and Ni uptake by spinach than those produced at 350 °C, attributed to higher CaCO3 and lower acidic functional group content, which resulted in greater enhancement of soil pH. When comparing the biochars produced at the same temperature, the rice husk biochars were the most effective in reducing Ni bioavailability, likely due to their lower acidic functional group content and higher nano-silica content which resulted in higher soil pH values and potentially promoted the formation of Ni-silicates and hydroxides.

Abbreviations : Ni: Nickel; RHB: rice husk biochar; LRB: licorice root pulp biochar; WsEx: water soluble and exchangeable; CARB: carbonate form; RES: residual; MnOx; manganese oxides bound; AFeOx; amorphous iron oxides bound; CFeOx: crystalline iron oxides bound; OM: organic bound.  相似文献   
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