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141.
Aksu Neslihan Samadi Afshin Yalçınkaya Ahmet Çetin Tuğçe Eser Burcu Lay İncilay Öziş Türkan Nadir Öztaş Yeşim Sabuncuoğlu Suna 《Molecular and cellular biochemistry》2020,466(1-2):117-128
Molecular and Cellular Biochemistry - Aberrant structural formations of Cu/Zn superoxide dismutase enzyme (SOD1) are the probable mechanism by which circumscribed mutations in the SOD1 gene cause... 相似文献
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İlker Kurbetli Görkem Sülü Mehmet Aydoğdu Stephen Woodward Süleyman Bayram 《Journal of Phytopathology》2020,168(9):533-541
Since the summer 2017, severe decline symptoms have been observed on 10- to 25-year-old avocado trees in almost all commercial orchards planted in the Mediterranean coastal region of Turkey. Young, newly planted trees in infected orchards were also affected by the disease. Affected trees showed wilting, leaf discoloration, defoliation and severe dieback. Some trees were completely desiccated. Although fine roots of symptomatic trees usually were decayed, reddish brown cankers also occurred on taproots and lateral roots of heavily infected trees. The pathogens were isolated from necrotic root and soil samples of symptomatic trees, using selective medium and soil baiting, and were identified based on morphological features and DNA sequences of the internal transcribed spacer (ITS) region. One isolate each of Phytophthora cryptogea and P. palmivora was identified, while all other isolates were P. cinnamomi. In addition, a subcortical fan-shaped mycelium, characteristic of Armillaria spp., was observed in the stem base of a symptomatic tree and identified as Armillaria gallica by DNA sequences of the internal transcribed spacer (ITS) and the translational elongation factor 1-α (EF 1-α) gene regions. Pathogenicity of Phytophthora isolates was tested by stem inoculation on one-year-old avocado seedlings. Two months after inoculation, canker lesions developed on stems of seedlings inoculated by any of the three Phytophthora spp. In contrast, collenchyma callus formed over the wound points on control plants over the same time period. This is the first report of P. cinnamomi, P. cryptogea, P. palmivora and A. gallica causing root rot of avocado trees in Turkey. In addition, P. cryptogea and A. gallica are reported for the first time associated with disease on this host. Due to the severe symptoms and widespread occurrence, P. cinnamomi should be considered a potential threat to avocado cultivation and natural ecosystems of this region of Turkey. 相似文献
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A survey was conducted in Ankara and Eskisehir provinces of Turkey for determining anastomosis groups and pathogenicity of Rhizoctonia species associated with root and crown rot of wheat. Pathogenicity tests revealed that Rhizoctonia solani AG 8 caused the common symptoms of damping‐off and stunting. 相似文献
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TUBA BUCAK ECE SARAOĞLU ETİ E. LEVİ Ü. NİHAN TAVŞANOĞLU A. İdİl ÇAKİROĞLU ERIK JEPPESEN MERYEM BEKLİOĞLU 《Freshwater Biology》2012,57(8):1631-1642
1. Water‐level fluctuations are typical of lakes located in the semi‐arid Mediterranean region, which is characterised by warm rainy winters and hot dry summers. Ongoing climate change may exacerbate fluctuations and lead to more severe episodes of drought, so information on the effects of water level on the functioning of lake ecosystems in such regions is crucial. 2. In eutrophic Lake Eymir, Turkey, we conducted a 4‐month (summer) field experiment using cylindrical 0.8‐m‐ (low‐water‐level) and 1.6‐m‐deep (high‐water‐level) mesocosms (kept open to the sediment and atmosphere). Fish (tench, Tinca tinca, and bleak, Alburnus escherichii) were added to half of the mesocosms, while the rest were kept fishless. Ten shoots of Potamogeton pectinatus were transplanted to each mesocosm. 3. Sampling for physicochemical variables, chlorophyll a (chl‐a), zooplankton and per cent plant volume inhabited (PVI%) by macrophytes was conducted weekly during the first 5 weeks, and subsequently biweekly. Macrophytes were harvested on the last sampling date. During the course of the experiment, the water level decreased by 0.41 ± 0.06 m. 4. Throughout the experiment, fish affected zooplankton abundance (?), nutrient concentrations (+), chl‐a (+) and water clarity (?) most strongly in the low‐water‐level mesocosms and the zooplankton community shifted towards dominance of small‐sized forms. The fishless mesocosms had a higher zooplankton/phytoplankton ratio, suggesting higher grazing. 5. Greatest macrophyte growth was observed in the low‐water‐level fishless mesocosms. However, despite high nutrient concentrations and low water clarity, macrophytes were also abundant in the fish mesocosms and particularly increased following a water‐level decrease from midsummer onwards. Macrophyte growth was poor in the high‐water‐level mesocosms, even in the fishless ones with high water clarity. This was ascribed to extensive periphyton development reducing light availability for the macrophytes. 6. Our results indicate that a reduction in water level during summer may help maintain the growth of macrophytes in Mediterranean eutrophic shallow lakes, despite a strong negative effect of fish predation on water clarity. It is therefore probable that an expected negative effect of global climate change on water clarity because of eutrophication and enhanced top‐down control of fish may be, at least partly, counteracted by reduced water level, provided that physical disturbance is not severe. 相似文献
146.
The aim of the study was to determine the boron contents of some wild-growing mushrooms collected from the vicinity of several
boron mines located in Balikesir, Turkey and compare the boron contents of some mushroom and soil samples. The locations of
the mushroom samples collected were within the distance of 0–100, 100–500, and 500–1,000 m to the mines. Soil samples were
taken from beneath randomly selected fungal fruit bodies. A total of 40 mushroom samples were found in the study area and
37 different species were identified. Among the 40 samples analyzed, the highest boron content was detected to be 273 mg kg−1 in Suillus collinitus. Also, Tricholoma terreum (69.52 mg kg−1), Myxomphalia maura (36.52 mg kg−1), Otidea concinna (30.70 mg kg−1), Sepultaria arenosa (28.94 mg kg−1), Melanoleuca paedida (28.33 mg kg−1), and Lycoperdon lividum (28.31 mg kg−1) relatively have high levels of boron and these species are proposed as candidates for boron accumulation. The boron contents
of the other mushrooms varied and a pattern was observed where the boron content was found to be decreased as the distance
from the mines increased. 相似文献
147.
The impact of ozone (O3) on European vegetation is largely under‐investigated, despite huge areas of Europe are exposed to high O3 levels and which are expected to increase in the next future. We studied the potential effects of O3 on photosynthesis and leaf area index (LAI) as well as the feedback between vegetation and atmospheric chemistry using a land surface model (ORCHIDEE) at high spatial resolution (30 km) coupled with a chemistry transport model (CHIMERE) for the whole year 2002. Our results show that the effect of tropospheric O3 on vegetation leads to a reduction in yearly gross primary production (GPP) of about 22% and a reduction in LAI of 15–20%. Larger impacts have been found during summer, when O3 reaches higher concentrations. During these months the maximum GPP decrease is up to 4 g C m?2 day?1, and the maximum LAI reduction is up to 0.7 m2 m?2. Since CHIMERE uses the LAI computed by ORCHIDEE to estimate the biogenic emissions, a LAI reduction may have severe implications on the simulated atmospheric chemistry. We found a large change in O3 precursors that however leads to small changes in tropospheric O3 concentration, while larger changes have been found for surface NO2 concentrations. 相似文献
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İsmail Yapıcı Ahmet Altay Beyza Öztürk Sarıkaya Mustafa Korkmaz Alptuğ Atila İlhami Gülçin Ekrem Köksal 《化学与生物多样性》2021,18(3):e2000812
In this study, phenolic composition, and in vitro biological activities of ethyl acetate (EAE) and methanol (ME) extracts obtained from the aerial parts of endemic Tanacetum erzincanense were investigated. Total phenolic and flavonoid content of the extracts were determined by Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. Antioxidant capacity of the extracts was evaluated over radical scavenging (DPPH and ABTS) and metal ion reducing power (FRAP and CUPRAC) tests. Individual phenolic compounds in ME was analyzed by high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS). Cell inhibitory potential of the extracts was tested against colorectal adenocarcinoma (HT-29), breast adenocarcinoma (MCF-7), and hepatocarcinoma (HepG2) cells by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. The results showed that ME contains higher TPC (64.4 mg GAE/g) and TFC (62.2 mg QE/g) than those of EAE (41.5 mg GAE/g and 40.0 mg QE/g). LC-ESI-QTOF/MS analysis revealed that ME is rich in phenolic compounds, namely, chlorogenic acid, apigenin, quercetin, luteolin, and diosmetin. Antioxidant assay results indicated that ME possess stronger activity than EAE and a power that competes with synthetic antioxidants. XTT assay results demonstrated that although both extracts displayed a considerable cytotoxicity against the tested cancer cell lines in a time and dose-dependent manner, ME expressed its selective inhibitory action towards MCF-7 cells with an IC50 value of 20.4 μg/mL for 72 h. These results may serve as a basis for further in vivo studies to examine the potential applications of T. erzincanense in food and pharmaceutical industries. 相似文献
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