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21.
Stem analysis data of 432 trees were obtained from even-aged, pure natural stands of Calabrian pine in the central Mediterranean Region of Turkey. Eight dynamic site equations derived with the Generalized Algebraic Difference Approach (GADA) were compared, based on autoregressive analysis and a thorough evaluation of the goodness of fit. We used generalized nonlinear least squares methods for model fitting. The adjusted coefficients of determination (0.9825–0.9842), root-mean-square errors (0.8004–0.8435 m), and Akaike’s information criterion differences (0–145) indicated a good fit of the eight site index equations. The Hossfeld equation (M3) provided the best result. The Durbin-Watson test statistic did not reveal an autocorrelation issue while the Hossfeld equation provided a satisfactory solution to the serial correlation problem in stem analysis data as time series using autoregressive modeling. This study presents new site index models for Calabrian pine forests in the central Mediterranean region of Turkey where it is the most important commercial tree species. The site index equation, based on the Hossfeld model is recommended for height growth prediction and site classification of Calabrian pine stands in the central Mediterranean region of Turkey, providing a new basis for growth prediction and yield estimation in these important forest ecosystems. 相似文献
22.
Ozluk A 《Pakistan journal of biological sciences: PJBS》2010,13(15):748-752
The purpose of this study is to examine the effects of neurosecretory material (NSM) in Corpus Allatum (CA) of endoparasitic Pimpla turionellae L. on reproduction. For this purpose, the egg maturation of the insect and the amount of the NSM in CA of the serial section of the brain were studied. Egg maturation was determined by measuring the terminal oocyte length. In order to determine the amount of the NSM in CA the neurosecretory granules of which were stained by paraldehyde fuchsin are considered. The egg maturation of P. turionellae have performed twice. The NSM intensity in CA continued increasingly from the first day of egg development until the first oviposition days; and reached the maximum level before the second egg maturation phase. These observations showed that the NSM in CA of this insect may be related to egg development. 相似文献
23.
Hugo Ferney Gomez-Becerra Atilla Yazici Levent Ozturk Hikmet Budak Zvi Peleg Alexey Morgounov Tzion Fahima Yehoshua Saranga Ismail Cakmak 《Euphytica》2010,171(1):39-52
Nineteen wild emmer wheat [Triticum turgidum ssp. dicoccoides (Körn.) Thell.] genotypes were evaluated for the grain concentrations of phosphorous (P), potassium (K), sulfur (S), magnesium (Mg), calcium (Ca), zinc (Zn), manganese (Mn), iron (Fe) and cooper (Cu) under five different environments in Turkey and Israel. Each mineral nutrient has been investigated for the (1) genotype by environment (G × E) interactions, (2) genotype stability, (3) correlation among minerals and (4) mineral stability. Among the macronutrients analyzed, grain concentrations of Ca (range 338–2,034 mg kg?1) and S (range 0.18–0.43%) showed the largest variation. In the case of micronutrients, the largest variation was observed in the grain Mn concentration (range 13–87 mg kg?1). Grain concentrations of Fe and Zn also showed important variation (range 27–86 and 39–115 mg kg?1, respectively). Accessions with higher nutrient concentrations (especially Zn and Fe) had also greater grain weight, suggesting that higher grain Zn and Fe concentrations are not necessarily related to small grain size or weight. Analysis of variance showed that environment was the most important source of variation for K, S, Ca, Fe, Mn and Zn, explaining between 44 and 78% of the total variation and G × E explained between 20 and 40% of the total variation in all the minerals, except for S and Zn where its effect accounted for less than 16%. Genotype was the most important source of variation for Cu (explaining 38% of the total variation). However, genotype effect was also important for Mg, Mn, Zn and S. Sulfur and Zn showed the largest heritability values (77 and 72%, respectively). Iron exhibited low heritability and high ratio value between the G × E and genotype variance components \( \left( {\sigma_{\text{GE}}^{2} /\sigma_{G}^{2} } \right) \), suggesting that specific adaptation for this mineral could be positively exploited. The wild emmer germplasm tested in the current study revealed some outstanding accessions (such as MM 5/4 and 24-39) in terms of grain Zn and Fe concentrations and environmental stability that can be used as potential donors to enhance grain micronutrient concentrations in wheats. 相似文献
24.
Emel Topuz Egemen Aydin Elif Pehlivanoglu-Mantas 《Water, air, and soil pollution》2012,223(9):5793-5802
N-nitrosodimethylamine (NDMA) is one of the most important disinfection by-products (DBPs) due to its carcinogenicity even at low concentrations which correspond to the levels occurring in drinking water and wastewater effluents. Therefore, NDMA is a candidate DBP that is expected to be regulated in the near future. However, the measurement of NDMA in the low nanogram per liter range is challenging because of the limitations of analytical techniques including both the sample preparation and the LC-MS/MS. Moreover, the accuracy of most of the current methods is only tested for drinking water and no information is present for other matrices. In this study, a combination of solid-phase extraction (SPE) and LC-MS/MS method that does not require high-resolution MS or advanced techniques for sample pretreatment is developed. Moreover, important factors that affect the optimization of the SPE method are provided to enable readers to optimize their own SPE procedures if necessary. The proposed method was validated for surface water, groundwater, and wastewater samples and the method quantification limit was 2?ng/L. In addition, the proposed method was used to determine the concentration of NDMA precursors measured as NDMA formation potential (NDMAFP) throughout a drinking water treatment plant at two different sampling periods. NDMAFP decreased by approximately 40?% in both samples. The concentrations ranged between 4 and 11.5?ng/L and the presence of these low concentrations underlines the need for an easy to use, yet sensitive method for the determination of NDMA in environmental matrices. 相似文献
25.
Prof. Dr. Aydin Gunes Ali Inal Mehmet Alpaslan Nuray Cicek Esra Guneri Figen Eraslan 《Archives of Agronomy and Soil Science》2013,59(6):687-695
Abstract It has been proposed that salicylic acid (SA) acts as an endogenous signal molecule responsible for inducing environmental stress tolerance in plants. In this study, the effects of seed soaked (1.0 mM for 24 h) and soil incorporated (0.1 mM and 0.5 mM) salicylic acid (SA) supply on growth and mineral concentrations of maize (Zea mays L., Hamidiye F1) grown under either salt, boron toxicity or drought-stressed conditions were investigated. Exogenously applied SA either with seed soaked (SS) or soil incorporated (SI) increased plant growth significantly in all the stresses conditions. Salicylic acid inhibited Na and Cl accumulation in saline conditions, and 0.5 mM of soil incorporated SA decreased B significantly in boron toxicity treatment. Except in drought condition, SA treatments stimulated N accumulation in plants. And P, K, Mg and Mn concentrations of SA received plants were increased in the stress conditions. These results suggest that SA regulates the response of plants to the environmental stresses and could be used as a plant growth regulator to improve plant growth and stimulate mineral nutrient concentrations under stress conditions. 相似文献
26.
The effect of varying hydrogel (0, 0.5, and 1.0% w/w) supply on some agro-physiological properties, such as dry matter, nutrient contents, chlorophyll contents, proline content, and ionic balance of bean plants in different salt sources and stress due to doses were investigated. Plants were treated with eight salt sources [sodium chloride (NaCl), sodium sulfate (Na2SO4), calcium chloride (CaCl2), calcium sulfate (CaSO4), potassium chloride (KCl), potassium sulfate (K2SO4), magnesium chloride (MgCl2), magnesium sulfate (MgSO4)] and four concentrations (0, 30, 60, and 120 mM doses) for 60 days in a growth media. Salt type, doses, and hydrogel (HG) affected the soil electrical conductivity. Soil salinity affected the parameters considered, and changed the nutrient balance of plants. High salt concentration caused substantial reduction in plant growth. Different salt concentrations negatively affected plant dry weight. The highest decrease of plant root dry weight was obtained with NaCl application followed by Na2SO4, CaCl2, CaSO4, MgCl2, MgSO4, KCl, and K2SO4, and similarly NaCl, Na2SO4, CaCl2, CaSO4, KCl, K2SO4, MgCl2, and MgSO4 in root dry weight. Total chlorophyll and nitrate contents of plants decreased with increasing salt doses, and the lowest value was obtained for NaCl application. Proline contents of plants were increased with increasing salt doses, and the highest value was obtained with the NaCl application. The effects of salt concentrations in nitrogen (N), potassium (K), and phosphorus (P) content of plants were significant. The presence of salt in the growth medium induced an important decrease the macro nutrient of the root and shoot part of plant such as N, P, K, calcium (Ca), and magnesium (Mg) content, but the N and P content of root and shoot part of the plant were increased with increasing of the HG application doses. The highest N and P increases were obtained with the 1.0 HG application for all salt types for both the root and shoots of plants. The HG added to saline soil significantly improved the variables affected by high salinity and also increased plant N and P, reduced soil electricity conductivity, nitrate, proline, and electrolyte leakage of plants, enhanced plant root and shoot dry weight by allowing nutrients and water to release to the plant as needed. The results suggested that HG has great potential for use in alleviating salinity stress on plant growth and growth parameters in saline soils of arid and semi-arid areas. This HG appears to be highly effective for use as a soil conditioner in vegetable growing, to improve crop tolerance and growth in saline conditions. It is intended to confirm the results of these studies by field trials. 相似文献
27.
ABSTRACT Phosphorus (P) efficiency (shoot dry weight at low P/shoot dry weight at high P) of a cultivar is the ability to produce a high yield in a soil that is limited in that element for a standard genotype. The large variation in P efficiency of different crops provides opportunities for screening crop species that perform well on low phosphorus soil. To explain the differences in P efficiency of sunflower (Helianthus annuus L.) cultivars a glasshouse pot experiment was conducted by using P-deficient soil [0.5 M sodium bicarbonate (NaHCO3)-extractable P 8.54 mg kg?1] treated with 0 (low P) and 100 mg P kg?1 soil (high P). The relationship between P efficiency and P, calcium (Ca), iron (Fe), zinc (Zn), and manganese (Mn) nutrition and anthocyanin accumulation was investigated in ten sunflower cultivars. Phosphorus deficiency resulted in significant decreases in the shoot and root yield. Phosphorus-efficient cultivars have the ability to produce higher yield than the inefficient cultivars in a limited P conditions. Our results showed that P-efficient cultivars had lower P concentrations, but higher P content in low P conditions. Phosphorus-efficient cultivars also have lower Ca and Fe concentrations in low P conditions but not in P-sufficient conditions. Applied P resulted in significant decreases in Zn concentrations in the shoots of the cultivars. Anthocyanin concentrations showed an accumulating pattern in all cultivars under P deficiency. The results demonstrated that phosphorus efficiency of the sunflower cultivars depends on their ability to produce higher yield and take up more P, and lower the concentration of Ca and Fe in shoots under low P conditions. 相似文献
28.
Melahat A. Birsin M. Sait Adak Ali Inal Abbas Aksu Aydin Gunes 《Journal of plant nutrition》2013,36(2):267-284
Growth stage effects on distribution of mineral nutrients or beneficial elements phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), chloride (Cl), iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), molybdenum (Mo), sodium (Na), silicon (Si) and nickel (Ni), and the elements bromine (Br), rubidium (Rb), strontium (Sr), barium (Ba), lanthanum (La), cerium (Ce), and uranium (U) in two barley (Hordeum vulgare L.) cultivars and how the distribution of these elements changed were determined during the 2006–2007 growing season in a field experiment. Barley plants were sampled from the field at shooting, heading, soft dough, hard dough and harvest stages, and mineral nutrients and other elements concentrations of spike, flag leaf, old leaf, and stem samples were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Distribution patterns varied considerably from element to element. At the end of the season much of the Ca, Mg, S, Si, Fe, Mn, Cu, Ni, Sr, Ba, La, Ce, and U were located in the spikes. However, much of the P, K, Zn, Cl, Na, Br, and Rb remained in the old leaves or stem. 相似文献
29.
Ozge Sahin Mehmet B. Taskin Yusuf K. Kadioglu Ali Inal David J. Pilbeam Aydin Gunes 《Journal of plant nutrition》2014,37(3):458-468
Poultry manure (PM) has been traditionally applied to crops for decades as an organic fertilizer, because it is a good and balanced source of plant nutrients. Its effect on plant growth and yield has been widely investigated and is well known. However, there has been little effort to relate elemental compositions of the manure applied to their concentrations in the plants. The objective of this study was to examine the effects of PM on the growth, and essential and non-essential element composition of pepper (Capsicum annuum) leaves and also fruits. Pepper plants were grown in soil with 0, 10, 20, and 40 g kg?1 PM under greenhouse conditions. Concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), silicon (Si), aluminum (Al), iron (Fe), zinc (Zn), copper (Cu), manganese (Mn), molybdenum (Mo), chloride (Cl), nickel (Ni), bromine (Br), rubidium (Rb), strontium (Sr), barium (Ba), lanthanum (La), and cerium (Ce) in leaves at the flowering stage and in fruits were determined by polarized energy dispersive X-ray fluorescence (PEDXRF). Poultry manure fertilization significantly improved pepper shoot growth and also fruit yield, and increased leaf and fruit P concentrations but not N, K, Mg, Si, Al, Ni, and Fe. Leaf Ca was significantly reduced by increased rate of PM application. Applied PM increased the concentrations of leaf and fruit Zn and Cl. Poultry manure applications had a positive effect on the concentrations of leaf Cu, and fruit Mn. The concentrations of Rb and Ce in fruits and Br in fruit and leaves were increased by PM treatments. Applied PM levels had no clear effect on the concentrations of Ba and La in pepper leaves. The leaf Ba was the highest with 10 g kg?1 PM, and leaf La was higher in 20 and 40 g kg?1 PM treatments than in the control. 相似文献
30.
Murata vortex spinning system is based on the air jet spinning system. The vast majority of previous works deal with the properties
of vortex spun (VS) yarn and the spinning system. In this study, we investigated knitted fabrics from VS yarn in comparison
with fabrics from ring (RS), compact (CS) and open-end rotor (OES) spun yarns made from viscose. The effect of yarn spinning
system on dimensional and physical properties of knitted fabrics was explained with specific attention to fabrics from VS
yarn. Shrinkage of fabrics from VS yarn has the lowest at widthwise direction, while having the highest at lengthwise direction.
It is shown that the order of fabric spirality and twist liveliness for yarns from different spinning systems are quite similar.
However, relation between loop shape factor and angle of spirality is inconsistent. Angle of spirality of fabrics from VS
yarn is higher than fabrics from OES yarn, but lower than that of others. The bursting strength of fabrics from VS yarn is
lower than that of those from RS and CS yarns and higher than that of those from OES yarn. From this study, it is also evident
that fabrics from VS yarn have the lowest pilling tendency and highest resistance to abrasion. 相似文献