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1.
To study the bark beetle attacks on Turkish fir stands and to determine the principle site and stand factors influencing beetle attacks, trap log method was used in the Western Black Sea Region of Turkey. The study was carried out in ten different locations prior to flying time in February 2003. On each experimental plot, three healthy fir trees with 30–50 cm diameter and 200 m apart were cut down with a chainsaw. From each sampling tree, needles were sub-sampled for determination of specific leaf-area and macro-nutrient concentrations. In addition, on each experimental plot, crown closure, basal-area, and stand density were measured. To determine the bulk density and nutrient concentrations of the soil, samples were taken around trees on each plot. The relationship between measured stand variables, the number of beetle species and beetle populations were evaluated using correlation and stepwise multiple regression procedure. Eight different species belonging to four different families from Coleoptera were identified in examining the trap logs. Six of these eight species (Pissodes piceae Illig., Pissodes notatus Fabr., Cryphalus piceae Ratz., Pityophthorus pityographus Ratz., Xyloterus lineatus Oliv., Pityokteines curvidens Germ.) were identified as harmful beetles (HB). The other two (Thanasimus formicarius L. and Rhizophagus dispar Payk.) were identified as predator species. The analysis showed that the total number of HB increased as the site’s slope and needle specific leaf area increased. However, as needle N concentrations increased, HB population decreased. Increased Ca concentration in fir needle reduced total insect attack.  相似文献   
2.
The fatty acid, sn-2 fatty acid, triacyglycerol (TAG), tocopherol, and phytosterol compositions of kernel oils obtained from nine apricot varieties grown in the Malatya region of Turkey were determined ( P<0.05). The names of the apricot varieties were Alyanak (ALY), Cataloglu (CAT), C?loglu (COL), Hacihaliloglu (HAC), Hacikiz (HKI), Hasanbey (HSB), Kabaasi (KAB), Soganci (SOG), and Tokaloglu (TOK). The total oil contents of apricot kernels ranged from 40.23 to 53.19%. Oleic acid contributed 70.83% to the total fatty acids, followed by linoleic (21.96%), palmitic (4.92%), and stearic (1.21%) acids. The s n-2 position is mainly occupied with oleic acid (63.54%), linoleic acid (35.0%), and palmitic acid (0.96%). Eight TAG species were identified: LLL, OLL, PLL, OOL+POL, OOO+POO, and SOO (where P, palmitoyl; S, stearoyl; O, oleoyl; and L, linoleoyl), among which mainly OOO+POO contributed to 48.64% of the total, followed by OOL+POL at 32.63% and OLL at 14.33%. Four tocopherol and six phytosterol isomers were identified and quantified; among these, gamma-tocopherol (475.11 mg/kg of oil) and beta-sitosterol (273.67 mg/100 g of oil) were predominant. Principal component analysis (PCA) was applied to the data from lipid components of apricot kernel oil in order to explore the distribution of the apricot variety according to their kernel's lipid components. PCA separated some varieties including ALY, COL, KAB, CAT, SOG, and HSB in one group and varieties TOK, HAC, and HKI in another group based on their lipid components of apricot kernel oil. So, in the present study, PCA was found to be a powerful tool for classification of the samples.  相似文献   
3.
Macrolides are considered to be one of the safest anti-infective groups in clinical use, with severe adverse reactions being rare. However, there are limited data about their embryotoxicity and teratogenicity. We aimed to investigate and compare the effects of these agents on embryonic growth and development. Rat embryos were cultured in vitro for 48 h in rat serum. Whole rat serum was used as a culture medium for the control group while different concentrations of spiramycin and azithromycin (1.25-6.25 microg/ml), and clarithromycin (2.5-30 microg/ml) were added to rat serum for the experimental groups. Dose-dependent effects of macrolides on embryonic developmental parameters were compared using morphological methods. Embryos were evaluated for the presence of any malformations. After morphological examination of the embryos, total DNA was extracted from the cells using standard procedures to determine fragmentation of nuclear DNA of embryonic cells. When compared with the control embryos, the macrolides significantly decreased all growth and developmental parameters dose dependently. While clarithromycin was found to cause more developmental toxicity than spiramycin and azithromycin, azitromycin was determined to have more teratogenicity potential. Compared with controls, there was no difference regarding the fragmentation of nuclear DNA of all the agents used. According to these results, when the toxic and teratogenic potential of the used agents compared, because of the lower toxic and teratogenic effects observed with spiramycin, this agent may be preferred for parturients.  相似文献   
4.
The aim of the present research was to investigate the fruit quality of twenty different local pear varieties (Pyrus communis L.), namely Ahlat, Ankara, Arpa, B?ld?rc?n, Çermai, Cinci, Gelin Bo?an, Hac? Hamza, Hah?r, Kabak, K?z?l, Kokulu, Mehrani, Menendi, Sulu, ?algam, Tokat Sultan?, Tur?u, Yaz, and Yaz Meyri?i, grown in Gumushane province in terms of pomological and morphological characteristics and chemical compositions. The fruit mass, fruit width and length, fruit stem thickness and length, fruit kernel width and length, hardness of pulp, number of seeds, leaf width and length, leaf stem length and thickness, and water soluble dry matter (WSDM) of the pear fruits have been determined as pomological and morphological characteristics. On the other hand, the chemical compositions of the pear varieties have been evaluated in terms of protein, ash, sucrose, fructose, glucose, total sugar, titratable acidity, moisture, and mineral element levels.Both pomological and morphological results demonstrated that the local pear varieties are important in terms of rehabilitation studies and detailed selection studies on these local varieties should be performed. The chemical analyses result of the pear varieties revealed that there is no component that may be harmful to human health when consumed, and also these varieties contains the necessary amount of mineral elements.  相似文献   
5.
The present study was conducted in order to determine the pomological and morphological characteristics and chemical compositions of some local apple varieties grown in Gumushane. As a result of field work in Gumushane province, sixteen different apples, which are Summer Apple, English apple, Green Belly, Black Belly and Yellow Belly Apples, Amasya Marble, Bey Apple, Chest Apple, Mahsusa, Arabian Girl, Willow Apple, Tav?anba??, Yellow H?d?r, Local Marble, Bride Apple, and Fatty Apple were collected in order to analyze. The average results of pomological and morphological properties and chemical compositions were obtained as following: fruit mass; 127.36 g, fruit width; 65.23 mm, fruit length; 57.30 mm, fruit stalk thickness; 2.17 mm, fruit stalk length; 17.63 mm, stalk pit depth; 12.75 mm, flower pit depth; 10.29 mm, fruit firmness; 13.79 kg/cm2, seed house width; 15.89 mm, seed house length; 17.39 mm, number of seeds; 4.3, water soluble dry matter content; 14.53?%, ash content; 1.11?%, pH; 3.8, titratable acidity; 0.69 g/L, water content; 83.8?%, reducing sugar; 5.04 g/100 g, sucrose; 2.25 g/100 g, and the amount of total sugars; 7.29 g/100. The fruit peel color was determined by considering the light transmittance (L). The average L values were ranged between 112.06 and 66.32. On the other hand among the mineral elements, potassium and manganese amounts were determined as the highest and the lowest, respectively.  相似文献   
6.
Thirty one pears genotypes from east blacksea region were evaluated for genetic relationships by using Randomly Amplified Polymorphic DNA (RAPD) and ISSR (Inter-Simple Sequence Repeats) markers from total 70 RAPD and ISSR primer investigated, 22 could amplify clearly and consistently. Cluster analysis of the pears genotypes was performed based on data from polymorphic bands RAPD and ISSR by using Jaccard’s similarity coefficient and the Unweighted pair-group method with arithmetic average (UPGMA) clustering method. The 31 pear genotypes were classified into two major groups. Cluster A was divided into 2 subclusters: Gumushane pears and Trabzon pears. Cluster B consisted of Artvin pears. The similarity matrix values ranged between 0.105 and 0.968.  相似文献   
7.
A nutrition trial was conducted to investigate the effects of dietary lipid levels and supplemental Ulva meal on growth performance, feed efficiency, nutrient utilization, and body composition of juvenile Nile tilapia, Oreochromis niloticus. Four isonitrogenous (CP 40%) diets containing 0% and 5% Ulva meal were formulated to contain 10% (low-lipid; LL) and 20% (high-lipid; HL) crude lipid. Triplicate groups of fish (~10 g) were fed to apparent satiation three times daily for 16 weeks. Fish fed 5% Ulva meal showed an increased growth performance (P < 0.05) compared with fish fed non-Ulva supplemented diets, irrespective of dietary lipid level. In particular, the incorporation of Ulva meal improved specific growth rate (SGR), feed conversion ratio (FCR), and protein efficiency ratio (PER). Feeding fish 5% Ulva meal diets resulted in significantly lower carcass lipid content. The results indicate that 5% inclusion of Ulva meal at both dietary lipid levels improves growth performance, feed efficiency, nutrient utilization, and body composition of Nile tilapia.  相似文献   
8.
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   
9.
This experiment was carried out in a mature (>100-year-old) eastern beech forest in the Eastern Black Sea Region (BSR) of Turkey. The effects of experimental practices to control the woody plant Rhododendron flavum Don., including grubbing, manual cutting, and foliar and cut-stump spraying with imazapyr and triclopyr, were assessed on understory and forest floor biomass and nutrients, as well as soil bulk density and nutrient content. The cut plots had 5, 15, and 38 times greater competing vegetation biomass than did the plots treated with triclopyr, grubbing, and imazapyr, respectively. Because of the increased biomass, the amount of understory N, P, Ca, K, S, and Mg content on the cut plots was also substantially higher when compared to the grubbed, imazapyr-treated, and triclopyr-treated plots. Triclopyr and imazapyr applications brought about two- and threefold greater dead organic matter on the forest floor than did cutting and grubbing, respectively. As a result, forest floor macronutrient contents on the imazapyr- and triclopyr-treated plots were significantly greater than on the cut plots. Five years after treatments, soil bulk density at the 10–20 cm depth on the imazapyr-sprayed plots was about 14% higher than that on other treatments. Herbicides, especially imazapyr and grubbing were effective in controlling rhododendron. Macronutrients stored in the rhododendron were released to the forest floor after vegetation was controlled with herbicides.  相似文献   
10.
Otoliths are calcareous anatomical structures in the inner ear of fishes, and they can be used in the discrimination of fish species and stocks due to their species-specific shape. Sagittal otoliths in the Lepidorhombus whiffiagonis and Lepidorhombus boscii, two flatfish species of the same genus distributed in the Aegean Sea, were compared using morphology, morphometry and contour shape analyses. Blind and eyed side otoliths of Lepidorhombus species were evaluated separately due to their morphological features and statistical differences in morphometric measurements (p < 0.05). Four analysis groups were formed: blind side otolith of L. whiffiagonis, eyed side otolith of L. whiffiagonis, blind side otolith of L. boscii and eyed side otolith of L. boscii. Morphometric differences in otolith shape were performed by canonical discriminant analysis, and the first discriminant axis explained 97.4% (Wilks λ = 0.270) of the variance between the groups, and the second axis explained 2.3% (Wilks λ = 0.620). Classification success between Lepidorhombus species based on CDA is 100%, and the overall CDA classification score between groups is 76.5%. The wavelet functions obtained in the contour analysis showed high variability in the anterior, posterior-dorsal, antero-dorsal and ventral regions of the otoliths among these four analysis groups. Consequently, it is thought that this study will contribute to the taxonomic classification of fish with the morphological and morphometric differences in the blind and eyed side otoliths and the analyses made with the high discrimination success obtained in Lepidorhombus species.  相似文献   
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