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1.
Vegetative compatibility (vc) and mating types and genetic diversity of Cryphonectria parasitica isolates were determined using 183 isolates obtained from 215 infected chestnut trees growing in 13 provinces of Turkey. Based on the cultural aspects, 143 of these isolates were evaluated as virulent whereas the remaining 40 isolates were hypovirulent. When vc types of 183 isolates were classically differentiated, 135 of them matched to EU-1 (82.3%), 29 of them to EU-12 (17.6%) vc type, whereas 19 of them did not match to the two. When molecular vic markers were used, all the isolates were assigned to two EU vc types; 149 to EU-1 (81.4%) and 34 (18.5%) to EU-12. Of the majority of the isolates, 134 (73.2%) had mating-type MAT-1, while 44 (24%) isolates had MAT-2 and 5 (2.8%) isolates had both mating types. The population analysis based on two DNA marker systems, Inter-Primer Binding Site and Start Codon Targeted Polymorphism, showed no intraspecific genetic variation among the C. parasitica isolates. The prevalence of two dominant vc types revealed by this study shows that biological control with hypovirulent EU-1 and EU-12 isolates will be significant for the country. The results might be helpful to chestnut breeders carrying out resistance breeding studies to manage this disease based on hypovirulence attributed to Cryphonectria hypovirus 1. 相似文献
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Gülsün Özyurt Yesim Özogul Caner Enver Özyurt Abdurrahman Polat Fatih Özogul Cengiz Gökbulut Beyza Ersoy Esmeray Küley 《Fisheries Science》2007,73(2):412-420
ABSTRACT: The effects of the different catching methods (gillnet, longline, harpoon) on sensory, chemical (pH, total volatile base nitrogen, K -value) and microbiological (total viable count [TVC]) changes in pike perch Sander lucioperca stored in ice were investigated. The same soaking time was used for both gillnet and longline fishing. The catching method had considerable influence on the freshness quality of pike perch. The acceptable shelf life was 15 days for pike perch caught by gillnet, and 22 days for longline and harpoon. The initial concentrations of inosine monophosphate (2.4 μmol/g) in pike perch caught by gillnet were significantly lower ( P < 0.05) than longline (4.1 μmol/g), and especially by harpoon (16.7 μmol/g). However, the initial K -values for fish caught by harpoon were significantly ( P < 0.05) lower (24.36%) than fish caught by longline and gillnet (57.69%, 64.41%, respectively). The average K , Ki, G and H -values at rejection day in terms of sensory assessment were approximately 90, 98, 156 and 40%, respectively, for all catching methods during ice storage. However, TVC reached 7.0 log cfu/g after approximately 11 days of storage for fish caught by gillnet, 19 days for fish caught by longline and 8 days for fish caught by harpoon. The result of this study suggests that the best catching method for preserving the freshness of pike perch is longline, based on the data obtained from the sensory and microbiological analysis. 相似文献
3.
İsmail Hamad Özlem Erol-Dayi Murat Pekmez Evren Önay-Uçar Nazlı Arda 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):44-49
The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular
oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed
a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC50 value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and
methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active
than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner.
Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate
that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used
as a natural additive in food, cosmetic and pharmaceutical industries. 相似文献
4.
Nılgün Kaba Özgül Özer Bengünur Çorapcı 《Journal Of Aquatic Food Product Technology》2017,26(10):1233-1243
In this study, the effects of natural and artificial colorants on the shelf life of hot smoked garfish were investigated in terms of its chemical, microbiological, and sensory quality. Turmeric and Sunset Yellow FCF were used as the natural and artificial colorants, respectively. The amount of total volatile basic nitrogen (TVB-N) and thiobarbituric acid (TBA), counts of total mesophilic aerobic bacteria, total psychrophilic aerobic bacteria, total yeast and molds increased during the storage (p < 0.05). The results showed that turmeric and Sunset Yellow FCF had a significant effect on pH value and salt content of hot smoked garfish samples during storage (p < 0.05). According to the sensory analysis results, the shelf life of hot smoked garfish stored at 4 ± 1ºC was determined as 17 days. 相似文献
5.
Muntala Abdulai Hüseyin Basım Esin Basım Derya Baki Nurhan Öztürk 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(2):471-484
Xanthomonas axonopodis pv. manihotis (Xam) is the causal agent of cassava bacterial blight (CBB) disease. CBB is a major constraint to cassava cultivation in Ghana. In this study, a survey was conducted in eight regions of Ghana to assess the presence of CBB disease. Out of the eight regions visited, CBB, though at different prevalence, was observed in five regions. Cassava plants samples showing suspected bacterial blight symptoms were collected for analysis by Polymerase Chain Reaction (PCR). The results of the analysis showed that Ashanti region had the highest prevalence in percentage of CBB, which recorded (70%), followed by Volta region (60%); Brong Ahafo region (40%); Eastern region (40%) and Greater Accra region (20%). Morphological examination of the putative pathogen was carried out on Cefazolin trehalose agar (CTA) and Nutrient agar (NA) media. The isolates were subjected to conventional PCR using Xanthomonas genus specific primer, RST2/RST3, Xam specific Variable Number Tandem Repeat (VNTRs) loci, XaG1_67F/R and X-gumD primers, which produced 840, 446 and 402 bp, respectively. The isolates also tested positive with SYBR Green fluorescent dye, using Real-time PCR. The resulting PCR products were sequenced and analyzed using a BLASTn program, which revealed homology between 93 and 100% with several other Xam strains retrieved from GenBank nucleotide database. The pathogenicity test of the isolates on the susceptible Esam cassava variety produced symptoms typical of Xam and the pathogen was consistently re-isolated from the inoculated cassava plants and thereby satisfying the Koch’s postulates. 相似文献
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7.
The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), is a major pest of pepper. In this study, we collected data on the development, survival, fecundity, and proportion of apterous and alate forms of green peach aphid reared on five commercial pepper cultivars (Amiral, Erciyes, Mert, Mertcan, and Naz) at 25?±?1°C, 60?±?5% RH, and a photoperiod of 16:8 (L:D) h. We analyzed the life history raw data by using the age-stage, two-sex life table. The shortest development time (6.66 days) and highest fecundity (62.68 individuals) occurred on the Erciyes cultivar. The highest intrinsic rate of increase (r?=?0.332 d?1), finite rate of increase (λ?=?1.394 d?1), net reproductive rate (R0?=?62.7 offspring) and shortest mean generation time (T?=?12.45 d) also occurred on the Erciyes cultivar; while the lower fitness occurred on the Amiral, Mertcan and Naz cultivars. Our results compared differences in the population growth rate of M. persicae on different pepper cultivars. This information will be useful to individuals working in pest management programs particularly those involving M. persicae. 相似文献
8.
Polypropylene (PP) fabrics were activated by an atmospheric pressure, dielectric barrier discharge to optimize the effects
of some discharge parameters on the dyeability of PP fabrics. Air and argon plasmas were used to modify the surfaces of the
fabrics, and the effects on dyeability were investigated when the treated fabrics were dyed by leuco and pigment forms of
vat dyestuffs. Surface properties of plasma-treated samples were characterized by Fourier transform infrared spectroscopy
(FTIR-ATR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Vat-dyed samples showed a significant
increase in color strength when PP fabrics were pretreated with atmospheric pressure plasmas of either argon or air. 相似文献
9.
Emel Alkan Fatih Kapukıran Elif Öztürk Er Dotse Selali Chormey Seyfullah Keyf Nizamettin Özdoğan Sezgin Bakırdere 《Water, air, and soil pollution》2018,229(9):298
The potential risk of pesticides to cause harm to humans and other organisms even at trace levels calls for sensitive and accurate analytical techniques for their simultaneous qualitative and quantitative determinations. In this study, a sensitive binary dispersive liquid-liquid microextraction (B-DLLME) strategy was developed for the simultaneous determination of phorate and oxyfluorfen by gas chromatography mass spectrometry after extraction/preconcentration from aqueous solution. An experimental design was used to optimize parameters of the B-DLLME method to obtain maximum outcome. Under the optimum conditions of B-DLLME, the limit of detection (LOD) for phorate and oxyfluorfen were found to be 0.41 μg L?1 and 0.54 μg L?1, respectively. The detection limits correlate to about 37 and 73 folds enhancement in detection powers when compared to direct GC-MS determination of phorate and oxyfluorfen, respectively. In order to find out the applicability of developed method to real samples, recovery tests were performed for 20 μg L?1 of phorate and oxyfluorfen spiked in well water samples. Percent recovery values were found to be 94.5% for phorate and 101.9% for oxyfluorfen. 相似文献
10.
Bülent Öztürk 《Fibers and Polymers》2010,11(3):464-473
This research work was concerned with the evaluation of the effect of fibre content on the mechanical properties of composites.
Composites were fabricated using jute/phenol formaldehyde (PF), rockwool/PF, and jute/rockwool hybrid PF with varying fibre
loadings. Jute and rockwool fibre reinforced PF composites were fabricated with varying fibre loadings (16, 25, 34, 42, 50,
and 60 vol.%). The jute/rockwool hybrid PF composites were manufactured at various ratios of jute/rockwool fibres such as
1:0, 0.92:0.08, 0.82:0.18, 0.70:0.30, 0.54:0.46, 0.28:0.72, and 0:1. Total fibre content of the hybrid composites was 42 vol.%.
The results showed that tensile strength of the composite increased with increasing fibre content up to 42 vol.% over which
it decreased for jute and rockwool fibre reinforced PF composites. Flexural strength of the composite was noted to peak at
a fibre loading of 42 vol.% for jute/PF composites, and 34 vol.% for rockwool/PF composites. Impact strength of jute/PF composites
increased with increasing fibre loading but that of rockwool/PF composites decreased at higher (>34 vol.%) fibre loadings.
Tensile, flexural, and impact strengths of jute/PF composites were found to be higher than those of rockwool/PF composites.
The maximum hardness values were obtained 42 vol.% for jute/PF composite, and 34 vol.% for rockwool/PF composite. Further
increase in fibre loading adversely affected the hardness of both composites. For jute/rockwool hybrid PF composites, tensile
and impact strengths decreased with increasing rockwool fibre loading. The maximum flexural strength of jute/rockwool hybrid
PF composites was obtained at a 0.82:0.18 jute/rockwool fibre ratio while maximum hardness was observed at a 0.28:0.72 jute/rockwool
fibre ratio. The fractured surfaces of the composites were analysed using scanning electron microscope in order to have an
insight into the failure mechanism and fibre/matrix interface adhesion. 相似文献