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71.
The objective of the current study was to characterize Fusarium oxysporum f. sp. radicis-cucumerinum isolates from cucumbers in Turkey in terms of pathogenicity, vegetative compatibility and amplified fragment length polymorphism (AFLP) variation. In the 2007 and 2008 greenhouse cucumber-growing seasons, surveys were conducted in Adana, Antalya, Hatay and Mersin provinces of the Mediterranean region of Turkey. Forty-seven fungal isolates of F. oxysporum were recovered from diseased cucumber plants. The pathogenicity of each isolate was tested on cucumber seedlings at the one-true-leaf stage. Forty of the 47 isolates of F. oxysporum were virulent on cucumber seedlings. Based on disease symptoms, the differential effect of temperatures of 17°C and 29°C on disease development, and the virulence on cucumber seedlings, these 40 isolates were identified as F. oxysporum f. sp. radicis-cucumerinum. Nitrate non-utilizing mutants were generated on minimal medium containing 1.5% KClO3 and their phenotypes were determined. Mutants in different phenotypic classes were paired on minimal medium; of 40 F. oxysporum f. sp. radicis-cucumerinum isolates, thirty-eight were placed into VCG 0260. Remaining two strains were assigned to VCG 0261. The AFLP primers produced a total of 180 fragments between 200 and 500 bp in length for the 30 isolates tested. At a genetic similarity of 0.71, the UPGMA analysis separated the isolates into two distinct clusters. The first cluster, AFLP I, included 28 isolates, of which all belonged to VCG 0260. Two strains in the second AFLP cluster both belonged to VCG 0261.  相似文献   
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A two year field experiment was conducted in field conditions using wheat (Triticum aestivum ssp. vulgare L. cv. Bezostaja) as the test plant for the evaluation of phosphate solubilizing (+PS) microorganisms. Bacterial strains significantly (P < 0.05) increased plant biomass (by 13 to 36%) without plant P enrichment. Only Bacillus sp. #189 significantly (P < 0.05) raised plant P-content, biomass and rhizosphere soil Olsen P at Zadoks Scale 62 simultaneously. Inoculations variably increased plant potassium (K-), magnesium (Mg-), zinc (Zn-), and managenese (Mn-) contents at harvest (Zadoks 92) but not earlier (Zadoks 31 and 61). The enrichment of the inoculated plants with nutrients other than P indicates the presence of alternative plant growth promoting mechanisms. This study showed that promising phosphate solubilizing microorganisms could increase not only the P content of the plants, but also the soil available P in rhizosphere transiently.  相似文献   
75.
Lack of bone formation-related health problems are a major problem for the aging population in the modern world. As a part of the ongoing trend of developing natural substances that attenuate osteoporotic bone loss conditions, dioxinodehydroeckol (DHE) from edible brown alga Ecklonia cava was tested for its effects on osteoblastogenic differentiation in MC3T3-E1 pre-osteoblasts. DHE was observed to successfully enhance osteoblast differentiation, as indicated by elevated cell proliferation, alkaline phosphatase activity, intracellular cell mineralization, along with raised levels of osteoblastogenesis indicators at the concentration of 20 μM. Results suggested a possible intervening of DHE on the bone morphogenetic protein (BMP) signaling pathway, according to elevated protein levels of BMP-2, collagen-I, and Smads. In addition, the presence of DHE was also able to raise the phosphorylated extracellular signal–regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) levels which are also activated by the BMP signaling pathway. In conclusion, DHE is suggested to be a potential bioactive compound against bone loss that could enhance osteoblastogenesis with a suggested BMP pathway interaction.  相似文献   
76.
The theoretical basis of the proposed technique is the cumulative variation of 137Cs measurements’ squared-differences between a reference and other sites. The change of the cumulative squared-differences with distance from the reference site is referred to as the point cumulative semivariogram (PCSV), which provides appropriate measure of cumulative similarity. Inspection of individual experimental PCSV provides local interpretation about the 137Cs radioactivity concentration around each site, whereas collective inspections provide possibility for grouping similar sites and hence identifying homogeneous sub-areas within the study area. It is also possible to prepare 137Cs radioactivity concentration maps based on pre-specified distances in each experimental PCSV, which lead to similarity levels. Such maps provide appreciation of 137Cs radioactivity concentration regional dependence in Keban Dam Lake, Turkey. Apart from the individual PCSV interpretations, the whole lake is divided into four distinctive classes.  相似文献   
77.
Citrus family especially Grapefruit, has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties. The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties. The total soluble solids (TSS), titratable acidity (TA) and pH of juice samples extracted from various grapefruit varieties differed significantly. The refractive index, specific gravity and optical rotation values for the oil varied from 1.473 to 1.396, 0.863 to 0.847 and +93 to +86, respectively. The percent 2,2-diphenyl-1-picrylhydrazyl radical activity (% DPPH activity) and ferric reducing antioxidant power (FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79, 2.91 to 1.44 mmol g–1 and 84.87 to 74.73, 7.76 to 5.73 mmol g–1, respectively. There were significant differences in physicochemical, antioxidant properties and volatile profiles of extracted juice and oil. The oil exhibited higher DPPH and FRAP values than the juice. Among different components identified which accounted for over 99% of the volatile fraction, limonene, myrcene, and benzopyran were major components in all oil samples.  相似文献   
78.
The effects of sodium borate (100 mg/kg body weight, p.o., 15 days) from a month before expected calving until a month after calving were evaluated in dairy cows susceptible to fatty liver. Cows received either sodium borate (n = 13) or no treatment (n = 10). All cows had mild fatty livers and increased plasma triglycerides and very low density lipoprotein (VLDL) concentrations at the beginning of the experiment. The control group of cows developed significant fatty liver after calving, and 2 of them had severe fatty liver associated with clinical and biochemical abnormalities. There were no clinicopathological signs related to sodium borate administration. Serum triglycerides and VLDL concentrations before calving decreased significantly at calving and after calving in controls, and they were within the normal range only after calving. There were significant alterations during the experiment in some hematological and chemical variables between groups, within period, but they were within the normal range. Unlike treated cows, serum triglycerides and VLDL concentrations correlated with liver fat content after calving in untreated cows. Our results document that sodium borate decreases the degree of fatty liver in dairy cows during early lactation.  相似文献   
79.
The efficacy of two-way combinations of Trichoderma endochitinase (CHIT42), synthetic peptide ESF12 and resveratrol upon the control of growth of Botrytis cinerea and Penicillium digitatum were evaluated in vitro. CHIT42 had effective concentration for 50% growth inhibition (EC50) values of 1.5 and 0.5 µM against B. cinerea and P. digitatum, respectively. CHIT42 also caused swelling, hyperbranching and bursting of P. digitatum at concentrations as low as 0.003 µM. The EC50 values of ESF12 were 30.9 and 29.2 µM against B. cinerea and P. digitatum, respectively. Resveratrol had EC50 values of 178.6 and 343.2 µM against B. cinerea and P. digitatum, respectively. Combinations of CHIT42 + ESF12, CHIT42 + resveratrol and ESF12 + resveratrol showed additive activity (interaction ratios between 0.5 and 1.5) against B. cinerea and P. digitatum.  相似文献   
80.
Two new coumarins, 7-methoxy-5-prenylcoumarin (isocedrelopsin) (1) and 3',4'-dihydrobraylin (2), were isolated from the trunk bark of Cedrelopsis grevei, along with five known coumarins, microfolicoumarin (6,7-dimethoxy-5-prenylcoumarin, (3), obliquin (4), 8-methoxyobliquin (5), aesculetin (6), cedrelopsin (7) and scoparone (8).  相似文献   
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