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Characterization of Pseudoperonospora cubensis isolates from Europe and Asia using ISSR and SRAP molecular markers 总被引:2,自引:0,他引:2
İlknur Polat Ömür Baysal Francesco Mercati Miloslav Kitner Yigal Cohen Ales Lebeda Francesco Carimi 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(3):641-653
Downy mildew caused by Pseudoperonospora cubensis is a major disease of cucurbits worldwide. New genotypes of the pathogen have recently appeared in the USA, EU and Israel causing breakdown of genetic resistance, expansion of host range, and the appearance of a new A2 mating type. Seventy-eight P. cubensis isolates were collected during 1996–2011 from cucurbits fields in different regions of Turkey, Israel and the Czech Republic and genetic diversity was analysed using highly polymorphic ISSR and SRAP molecular markers. The data acquired showed remarkable genetic diversity within and among the isolates. While isolates from Turkey and Czech Republic exhibited uniform genetic background, the isolates from Israel were clearly distinguished from the others. The results may indicate on migration and/or frequent sexual reproduction of the pathogen in Israel. Moreover the selected markers can be suggested for monitoring genetic diversity within P. cubensis isolates in further studies. 相似文献
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İhsan Çelik Pınar Çelik Şükran Cirik Mert Gürkan Sibel Hayretdağ 《Aquaculture Research》2012,43(9):1260-1275
The embryonic and larval development of black skirt tetra, Gymnocorymbus ternetzi, are described under controlled laboratory conditions. In addition, major histomorphological changes and the allometric growth patterns during larval development have been described. The laboratory‐reared broodstock, that is 1 year of age, were spawned. Hatching occurred 20–21 h after spawning at 24 ± 0.5°C. The cleavage was finished in 2 h and the early blastula stage occurred at 2:04 hours after spawning. The gastrulation started at 3:20 hours and 30% epiboly was observed at 3:34 hours after spawning. Eight‐somite stage was observed at 08:33 hours. And embryonic developmental stage was completed at 21 h after spawning. The newly hatched larvae were 1442 ± 14.3 μm in mean total length (TL). The mouth opened at 3 days after hatching (DAH). The yolk sac had been totally absorbed and the larvae started to swim actively within 3–4 days. Notochord flexion began at 11 DAH. The metamorphosis was completed and the larvae transformed into juveniles at 32 DAH. In this paper, the full developmental sequence from egg to juvenile of G. ternetzi is described for the first time. 相似文献
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Matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of several central nervous system (CNS) diseases. In this study, we investigated the presence of Listeria monocytogenes antigens and detected the expression of MMP-9 and MMP-7 in the brains of 22 sheep with clinical signs and histopathological findings characteristic of listerial meningoencephalitis. Archived sections from the brainstem, cerebrum, and cerebellum were stained for immunohistochemistry. L. monocytogenes antigens were located mainly in the cytoplasm of neutrophils and some macrophages and/or extracellularly within microabscesses of the brainstem. MMP-9 was mainly immunolocalised in the endothelial cells, microglial cells, and neurons especially in inflammatory areas. MMP-7 immunoreactivity was detected in perivascular cuffs, microglial cells, and only a few neurons. Overall, immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of encephalitic listeriosis caused by L. monocytogenes, and MMP-9 and MMP-7 may contribute to the pathogenesis of listerial meningoencephalitis. 相似文献
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İlhami Gülçin Riad Elias Akçahan Gepdiremen Khalil Taoubi Ekrem Köksal 《Wood Science and Technology》2009,43(3-4):195-212
Recently, a number of studies on health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. The fringe tree (Chionanthus virginicus) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. The potential antioxidant activities of two secoiridoids from root bark of fringe tree (Chionanthus virginicus L.) were investigated to evaluate their potential value as the natural products for foods or cosmetic applications. In this study, antioxidant activities were measured by 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O 2 ·? ) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H2O2) scavenging and ferrous metal chelating activity assays. These secoiridoids, as antioxidants neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analog of tocopherol, were used as the reference antioxidant compounds. Ligustroside (3.70 × 10?3 M) and oleuropein (3.80 × 10?3 M) showed 71.9, 82.4, 80.7 and 90.4% inhibition on lipid peroxidation of linoleic acid emulsion, at the concentrations of 10 and 20 μg/mL. On the other hand, 20 μg/mL of standard antioxidant such as α-tocopherol (4.64 × 10?3 M), trolox (7.98 × 10?3 M), BHA (10.08 × 10?3 M) and BHT (9.06 × 10?3 M) exhibited 61.5, 29.8, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, ligustroside and oleuropein had effective DPPH·, ABTS·+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA and BHT, α-tocopherol and trolox that are references antioxidants. 相似文献
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Eyüp Selim Köksal Tekin Kara Mehmet Apan Haluk Üstün Adem İlbeyi 《Irrigation and Drainage Systems》2008,22(3-4):209-223
Field experiments were carried out in the 2004 and 2005 growing seasons on drip irrigated dwarf green beans (Phaseolus vulgaris, humilis). Soil water content (SWC), spectral reflectance and yield were monitored. Based on these data crop evapotranspiration (ETc), soil water deficit index (SWDI), water use efficiency (WUE) and four separate spectral indexes were calculated. In order to determine use opportunities of spectral indexes for estimation of yield, SWDI and WUE, some statistical analyzes were made. Results showed that spectral indexes could be used for monitoring of yield, SWDI and WUE. Especially, Soil Adjusted Vegetation Index (SAVI) had the highest correlations with all three of the parameters. The estimation procedure which was given in this study has a potential use either during, or at the end of the growing season. Estimated values of WUE and SWDI were 3.2 (kg m?3) and 0.12, respectively, through SAVI and the given procedure, indicates the optimal water use and yield conditions for dwarf green beans. At this situation, probably ETc was 580 mm and yield was 25.5 t ha?1. 相似文献
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Zhanerke Akhatayeva Cui Mao Fugui Jiang Chuanying Pan Chunjian Lin Kunjie Hao Tianxin Lan Hong Chen Qingfeng Zhang Xianyong Lan 《Reproduction in domestic animals》2020,55(11):1470-1478
Growth hormone and prolactin belong to the class of peptide hormones that have a wide range of regulatory functions. In this study, polymorphisms of growth hormone receptor (GHR) and prolactin (PRL) genes were analysed as candidate genes, which are responsible for the litter size in Australian White (AUW) sheep. According to the statistical analyses results, the polymorphism information content (PIC) values of the PRL-P1-ins-23 bp, GHR-P2-del-23 bp and GHR-P8-del-23 bp were 0.371, 0.366 and 0.375, respectively, which indicates the high genetic polymorphism in AUW sheep. Moreover, all indel loci are not conformed to the HWE (p < .05). Further, our findings revealed that the PRL-P1-ins-23 bp polymorphism in the ovine PRL gene was significantly related to the first parity litter size (p = .001) and the DD genotype displaying the highest genotypic mean. Meanwhile, the GHR-P2-del-23 bp and GHR-P8-23 bp indels in the ovine GHR gene were significantly correlated with first parity litter size (p < .05), and the individuals with the genotype II showed significantly higher litter size than others. Collectively, these results demonstrated that our findings could be useful for future sheep breeding strategies based on the molecular-assisted selection (MAS). 相似文献
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İlker Kurbetli 《Phytoparasitica》2014,42(5):627-630
Sweet cherry is a major commercial crop in Turkey, the most important producer of the fruit worldwide. Sweet cherry decline was observed in an orchard in Ankara province of Turkey. Affected young trees exhibited reduced tree vigor, yellowing and wilting of leaves, and dieback symptoms resulted in tree death. A Phytophthora sp. was consistently isolated from necroses that appeared on taproots and crowns. The pathogen was identified as Phytophthora cryptogea based on several morphological features and DNA sequence of the internal transcribed spacer (ITS) region. P. cryptogea was pathogenic on excised shoots and 1-year-old cherry rootstocks. This is the first report of P. cryptogea causing disease of sweet cherry in Turkey. 相似文献
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İsmail Çelik Hikmet Günal Mert Acar Nurullah Acir Zeliha Bereket Barut Mesut Budak 《Soil Use and Management》2020,36(2):223-239
Current agricultural practices and their impacts on the sustainability of crop production can be evaluated by simple and reliable soil structure assessment tools. The study was conducted to determine the effects of long-term (2006–2017) tillage systems on structural quality of a clayey soil using the visual evaluation of soil structure (VESS) and classical field and laboratory measurements. A field experiment with seven tillage systems, representing both traditional and conservation tillage methods, was conducted on a clayey soil in the Cukurova region, Turkey. Soil samples from 0–10, 10–20 and 20–25 cm depths were analysed for mean weight diameter (MWD), porosity and organic carbon. Penetration resistance (PR) was determined in each treatment plot. The VESS scores (<2) of upper 0–5 cm indicated a good structural quality for all tillage systems. The VESS scores were positively related to PR and MWD and negatively to macroporosity (MaP) and total porosity. In reduced and no-till systems, poorer soil structures were observed in subsurface layers where firm platy and angular blocky structures were defined. Mean VESS score (3.29) in 20–25 cm depth where PR was 3.01 MPa under no-till indicated a deterioration of soil structural quality; thus, immediate physical interventions would be needed. Lower VESS scores and PR values under strategic tillage which was created by ploughing half of no-till plots in November 2015 indicated successful correction of compaction caused by long-term no-till. The results suggest that the VESS approach is sensitive and useful in distinguishing compacted layers within the topsoil. 相似文献
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The tomato borer, Tuta absoluta (Meyrick), was first recorded in Turkey in August 2009 and rapidly became a serious pest in the Mediterranean and Aegean coastal regions in field and greenhouse grown tomatoes. Currently, insecticides are considered one of the major tools for the management of T. absoluta in Turkey. This study, investigated the efficacy of 7 different insecticides, against T. absoluta in laboratory bioassays. To determine the lethal concentration (LC) values and feeding activity of the larvae, tomato leaf parts mined by 1–3 day old L1 larvae were dipped into different insecticide concentrations. Mortality was recorded 5 days after insecticide treatments. Spinosad, chlorantraniliprole + abamectin or indoxacarb treatment resulted in 100% mortality with minimal or no feeding in all populations at their recommended doses of 120, 50.4 and 60 mg a.s. L?1, respectively. In general, the LC99 values of populations for these insecticides were similar and also lower than that of the recommended field doses. The effect of pyridalyl was low, resulting in low mortality with serious feeding damage at the dose of 125 mg a.s. L?1. The efficacies of abamectin, metaflumizone and azadirachtin were found to be moderate to low at the recommended doses (4.5, 240 and 50 mg a.s. L?1, respectively). However, these insecticides may affect pupation and adult emergence rates hence further studies are recommended to investigate these insecticides. 相似文献