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101.
102.
Potential decrease of grass tetany risk in rangelands combining N and K fertilization with MgO treatments 总被引:1,自引:0,他引:1
The most practical and effective method to increase dry matter production in rangelands is by adequate fertilization. N and K fertilizers have commonly been used worldwide to increase yield in rangelands. Fertilizers have a significant effect on mineral concentration in the forage. Risk of tetany, causing yield decrease and death in cattle, increases by feeding forage with a ratio of K/(Ca + Mg) ≥ 2.2. The fertilizers containing N and K are the most important factors increasing K/(Ca + Mg) ratio in forages. The present study has aimed to determine whether the tetany risks caused by K and N fertilization may be compensated by Mg fertilization. For this purpose, N (0 and 120 kg ha−1), K (0 and 100 kg ha−1) and Mg (0 and 30 kg ha−1) were applied as combinations of each other. Each plot was separated into three sub-plots sampled on 25 April, 15 May and 5 June to determine Ca, Mg, K concentrations and K/(Ca + Mg) ratio.In this 2-year study, dry matter production in the control plot was 2064 kg ha−1 and nitrogen application increased the dry matter production of the plots by about 100%. Dry weight ratios of grasses increased while legume dry weight ratios decreased drastically in response to N fertilization. An increase was observed in K/(Ca + Mg) ratio with N fertilization due to the fact that legumes have higher concentrations of Ca and Mg than grasses. K fertilization resulted in an approximately 30% increase of K concentration in dry matter. K/(Ca + Mg) ratio in plots where N and K were applied separately was lower than 2.2. However, K/(Ca + Mg) ratio in plots to which N and K were applied in combination was over 2.2, resulting in tetany risk. It is interesting to determine that Mg fertilization did not change Mg concentration in pasture. It was noted that tetany risk did not decrease with the advance of harvest dates. The results indicated that tetany risk caused by N and K fertilizations could not be compensated by Mg treatment. Therefore, it can be concluded that fertilization programmes avoiding legume decrease in rangelands may be useful to prevent the tetany risk. 相似文献
103.
A. Uzun O. Gulsen G. Kafa U. Seday O. Tuzcu T. Yesiloglu 《Scientia Horticulturae》2009,122(4):556-561
‘Mal secco’ is a serious disease of lemon and other citrus species, reduces lemon production, and limits the use of susceptible cultivars especially in the Mediterranean countries, against which there is no effective management system to control the disease. The objective of this study was to determine yield efficiency, tree and fruit characters, and molecular profiles of the selected promising genotypes in lemon breeding program to develop ‘mal secco’ tolerant lemon cultivars. After 4 years of evaluation, ‘Tuzcu 894’, a progeny of ‘Finike Yerli Yuvarlak’ and ‘Kutdiken’, was designated as promising genotype with high yield, fruit weight, juice content and low seed number contrary to ‘Kutdiken’ as control. ‘Tuzcu 8911’ was suitable for dense planting having the highest yield in CV. In addition, these two promising genotypes survived after many years being subjected to artificial and natural P. tracheiphila infections and harsh winter temperatures, which were attractive to the citrus industry. Molecular analysis, as assessed with 11 inter-simple sequence repeats (ISSR) primers, indicated that ‘Tuzcu 09 Aklimon’ and its selections, ‘Tuzcu 896’, ‘Tuzcu 897’ and ‘Tuzcu 898’, were distinct from the other genotypes with similarity value of 0.82. Genetic variation among the other lemon genotypes was low and some of the genotypes were identical. It was concluded that variations in the agronomical characters are mainly due to mutations. 相似文献
104.
Sequence related amplified polymorphism (SRAP) markers were used to detect molecular marker polmorphisms among 86 citrus and their relatives in Aurantioidea. Twenty-one SRAP primer combinations produced a total of 376 polymorphic fragments with an average of 17.9 per primer combination and an average polymorphism information content (PIC) of 0.86. The unweighted pair group method arithmetic average (UPGMA) analysis demonstrated that the accessions had a similarity range from 0.28 to 1.00 with a mean of 0.64. The subtribe Clauseninae (tribe Clauseneae) separated from the subtribes of the tribe Citreae. The subtribe Balsamocitrinae (tribe Citreae) was the most distant from the others. In the Citrinae, ‘primitive citrus fruit trees’ and ‘near citrus fruit trees’ groups did not clearly separate from each other but all genera in these groups were distinct. On the other hand, subgenus Papeda and subgenus Citrus were not separated clearly in the dendrogram. C. maxima, C. medica and C. reticulata separated into three distinct clusters in agreement with three ‘true basic species’ thesis. Similarity-based analyses supported the theory of few ancestral species in Aurantioidea. 相似文献
105.
An experiment was conducted to determine the effects of chloride (Cl) and reduced forms of nitrogen (N) on the nitrate (NO3), total N, and Cl concentrations in onion (Allium cepa L.) plants using a non‐recirculating nutrient film growing system. The reference treatment was a nutrient solution containing 19 mM NO3 and 1.25 mM ammonium (NH4). The results from this treatment were compared with that obtained using mixed amino acid, urea, and glycine treatments with or without additional Cl (10 mM) in which 20% of the NO3 in the reference treatment was substituted with one of these reduced forms of N. Fresh and dry weights of the onion plants were not affected by the treatments. The NO3 content was considerably lower in the mixed amino acid treatment, being 4236 mg NO3/kg FW as compared to either the reference, urea, or glycine treatments. The NO3 contents of the plants in these treatments were 5393, 5339, and 5261 mg NO3/kg FW, respectively. The presence of Cl in the nutrient solution also reduced the NO3 content of the plants from 5816 to 4299 mg NO3/kg FW. The reduced‐N treatments increased the total N contents of the plants. The Cl content of the plants was increased by the Cl supplied and by the reduced forms of N in the nutrient solution. 相似文献
106.
Berrin Ziyadanoğullari Firat Aydin Işil Aydin Hasan Bingöl 《Archives of Agronomy and Soil Science》2013,59(4-5):371-376
Removal of Cd (II) from aqueous solution by a soil containing magnesite and thermal activated soil containing magnesite was investigated. Maximum activation temperature was determined at 700°C for 2?h and maximum adsorption capacities were determined as 4.20?mg/g for natural magnesite, 38.91?mg/g for thermal activated magnesite at 25°C respectively. Equilibrium contact time of cadmium was determined for 2?h. Adsorption of Cd (II) on soil containing magnesite conforms to Langmuir's isotherm. 相似文献
107.
Aydin Adiloglu 《Archives of Agronomy and Soil Science》2013,59(6):553-556
It is widely accepted that plants absorb more Cd when they suffer from Zn deficiency, as the Zn deficiency is a critical problem in the world. The effect of increased Cadmium (Cd) application (0 and 15 mg kg-1 Cd) on growing and Cd concentration in some cereal species was investigated at the increasing rate of Zinc (Zn) applications (0 and 15 mg kg-1 Zn). The experiment was carried out under greenhouse conditions using a Zn deficient soil. According to the results, that increased Cd applications severely reduced dry matter production of plants. Dry matter production decreased in the following order: bread wheat > oat > maize > barley. These decreases were determined to be statistically significant (P < 0.01). Cd concentration of cereal species increased with the application of increasing rate of Cd, with a similar trend to that of the dry matter. Dry matter production of plants increased and Cd concentrations of plants decreased with the application of increasing rate of Zn. These results show that Cd accumulation of plant increase in Zn deficient soils. Cd accumulation in plants is hindered with the application of Zn. 相似文献
108.
Arcobacter cryaerophilus was isolated from naturally infected rainbow trout (Oncorhynchus mykiss Walbaum), and its pathogenicity was tested by intramuscular injection into 40 healthy 1-year-old rainbow trout at 16 degrees C. The lethal dosage of 50% end point (LD50) for A. cryaerophilus was calculated 2.25 x 10(4) viable cells. Experimental infection caused deaths with gross clinical abnormalities such as degenerated opercula and gills, liver damage, haemorrhagic kidney and serous fluid in swollen intestines. The counts of A. cryaerophilus in kidney, liver and gills of experimentally infected fish ranged from 1.59 x 10(10) colony forming units (cfu)/g to 7.41 x 10(12) cfu/g. The means of erythrocyte (RBC) count, haematocrit level, serum cholesterol, triglyceride, albumin and total protein concentrations in the blood of the experimentally infected rainbow trout group were significantly lower than in the healthy fish. Leukocyte (WBC) counts of the experimentally infected rainbow trout were significantly higher than those of healthy fish. The present work shows that the selected blood characteristics may be good indicators of response to infections in rainbow trout. 相似文献
109.
Effects of curcumin on tumour necrosis factor-alpha and interleukin-6 in the late phase of experimental acute pancreatitis 总被引:6,自引:0,他引:6
Gulcubuk A Altunatmaz K Sonmez K Haktanir-Yatkin D Uzun H Gurel A Aydin S 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2006,53(1):49-54
Summary Inflammatory cytokines have been demonstrated to play an important role in the induction and severity of acute pancreatitis (AP) in the recent studies. The aim of this study was to investigate the effects of curcumin on inflammatory cytokines, such as tumour necrosis factor (TNF)-alpha and interleukin (IL)-6 in the late phase of AP. The study was conducted on 40 male Wistar Albino rats. The animals were divided randomly into four equal groups. AP was induced by the infusion of 3% sodium taurocholate into the biliopancreatic duct (in groups I and II). Starting on day 20 prior to the induction of AP, rats in group I received daily dose of 100 mg/kg of curcumin, dissolved in 9% ethanol via an intragastric tube. The same procedure was repeated for 6 days following the onset of AP. Group III was infused only on saline solution. Group IV (curcumin control group) received 9% ethanol via an intragastric tube, during the experimental period (totally 26 days). All the animals were sacrificed on day 6 after the collection of blood samples and serum TNF-alpha and IL-6 levels were determined. Tissue samples were taken from pancreas, mesenteric lymph nodes, liver, lungs, spleen and the kidneys for histopathological evaluation. Serum TNF-alpha and IL-6 levels in the group, which received curcumin (group I), were determined to be significantly lower than those of the untreated group (group II) (P<0.05). No statistically significant difference was detected in terms of total histopathological scores in the treatment group versus untreated group. Curcumin has been shown to markedly reduce serum TNF-alpha and IL-6 levels in the late phase of AP, but failed in the prevention of tissue injury. 相似文献
110.
The present study was carried out to investigate the modulating effects of thyme and its major components against the oxidative DNA damage induced by H(2)O(2). The human lymphocytes with thymol, carvacrol, and gamma-terpinene incubated with or without 0.1 mM H(2)O(2) for 30 min at 37 degrees C and the DNA damage were evaluated by singe cell gel electropheresis (comet assay). Concentrations above 0.1 mM thymol and gamma-terpinene and 0.05 mM carvacrol significantly induced DNA damage in human lymphocytes, but at the smaller concentrations no additional DNA strand breakage has been observed. At the all concentrations studied, gamma-terpinene did not show any protective effect against H(2)O(2) induced oxidative DNA damage, but the phenolic compounds thymol and carvacrol at concentrations below 0.2 and 0.1 mM, respectively, significantly reduced the oxidative DNA damage (p < 0.001). The n-hexane and ethyl acetate fractions prepared from the methanolic extracts of Thymus spicata also were found to inhibit DNA damage. 相似文献