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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.
Effects of stratification, desiccation, radicle pruning, and season of sowing on Quercus vulcanica germination and growth were studied to identify optimum nursery procedures for artificial regeneration of this species. Following stratification (0, 2, 4 and 8 weeks), acorns were germinated, and acorn moisture content and germination performance were also determined at various times during desiccation. In early December unsprouted acorns were planted in containers, and in early April sprouted acorns, which had been stored in polyethylene bags at 4 °C, with radicles left intact or with radicles pruned back to 1.0 cm were planted in containers.Stratification for 2 and 4 weeks did not increase germination percentage but significantly increased germination rate. Germination percentage of the seeds dropped when the moisture content of the seeds was reduced by desiccation, and the critical minimum moisture content of the recalcitrant Q. vulcanica acorns was found to be 11–16%. Spring sowing of sprouted acorns altered the morphology the containerized seedlings and caused the formation of significantly more main roots, but resulted in significantly less shoot height and shoot dry weight. Spring-sown sprouted acorns had also a significant advantage over the fall-sown unsprouted acorns in seedling survival, and thus nursery personnel should not be concerned if acorns sprout before sowing.  相似文献   
3.
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   
4.
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   
5.
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   
6.
Efficacy and mechanism of action of marine alkaloid 3,10-dibromofascaplysin (DBF) were investigated in human prostate cancer (PCa) cells harboring different levels of drug resistance. Anticancer activity was observed across all cell lines examined without signs of cross-resistance to androgen receptor targeting agents (ARTA) or taxane based chemotherapy. Kinome analysis followed by functional investigation identified JNK1/2 to be one of the molecular targets of DBF in 22Rv1 cells. In contrast, no activation of p38 and ERK1/2 MAPKs was observed. Inhibition of the drug-induced JNK1/2 activation or of the basal p38 activity resulted in increased cytotoxicity of DBF, whereas an active ERK1/2 was identified to be important for anticancer activity of the alkaloid. Synergistic effects of DBF were observed in combination with PARP-inhibitor olaparib most likely due to the induction of ROS production by the marine alkaloid. In addition, DBF intensified effects of platinum-based drugs cisplatin and carboplatin, and taxane derivatives docetaxel and cabazitaxel. Finally, DBF inhibited AR-signaling and resensitized AR-V7-positive 22Rv1 prostate cancer cells to enzalutamide, presumably due to AR-V7 down-regulation. These findings propose DBF to be a promising novel drug candidate for the treatment of human PCa regardless of resistance to standard therapy.  相似文献   
7.
The proximate properties, the fatty acid and mineral contents of different almond kernel varieties were determined. The crude protein contents of kernels ranged between 12.7% (guara) and 16.3% (cristomorto). The oil yields from these kernels were established between 48.8% (cristomorto) and 55.7% (ferragnes). The acidity value of oils were found between 1.389 and 3.559%. In addition, peroxide values were established between 7.586 (nonpareil) and 15.590 mequiv./kg (cristomorto). The major fatty acids of almond kernel oils were oleic (72.5–79.9%), linoleic (13.5–19.8%) and palmitic acids (5.9–6.7%). The predominant mineral in most kernel was potassium (13.1–15.1 mg/100 g). The mineral contents of the kernels were established as 7.94–9.38 mg/100 g potassium, 2.9–4.0 mg/100 g magnesium and 1.84–2.94 mg/100 g calcium. From the results of the present study, it can be concluded that the kernels of almond varieties are being potential sources of valuable oil which might be used for edible and other industrial applications.  相似文献   
8.
A 12‐week feeding trial was conducted to estimate the effects of supplemented amino acids (lysine and methionine) with different dietary protein levels on growth, haematology and liver histology in meagre (Argyrosomus regius) at two different sizes: fingerling (15.2 g) and juvenile (44.4 g). Six practical diets were prepared, and three of these practical diets were formulated with 40 (P40), 44 (P44) and 48% (P48) crude protein without supplementation of amino acids. Other three diets having same protein levels were supplemented with lysine and methionine (P40AA, P44AA and P48AA) to bring these amino acids level up to that estimated to be at the least in the 48% protein diet. Final mean weight (FMW) and specific growth rate (SGR) of P48AA in fingerlings were higher than that of 40AA. According to FMW and SGR of juveniles, there was interaction found between dietary protein levels and the supplementation of amino acids. The FMW and SGR of meagre fed P44AA were higher than that of fish fed the other diets, except fish fed the P48. Economic profit index, packed cell volume and haemoglobin for juvenile meagre were significantly improved with the dietary protein level and amino acid supplementation. The liver tissues of the P48 group in both sizes displayed better structure compared with the other groups. In conclusion, dietary crude protein content of practical diets for juvenile meagre could be reduced from 48% to 44% by adding essential amino acids with an enhancement in growth, health and economic profit.  相似文献   
9.
Cancer is a lethal disease that is characterized by uncontrolled cell division and proliferation, and it results in death in many organisms. Doxorubicin (DOX) is a therapeutic agent used for treatment of many cancer types, but it induces serious hepatotoxicity. In this study, we aimed to determine possible hepato-therapeutic effects of thymoquinone (THQ) on DOX-induced hepatotoxicity in rats. Rats were divided into five groups (n = 8): Control, THQ (10 mg/kg/day/i.p for 14 days), Olive Oil (equal volume with THQ for 14 days), DOX (single dose, 15 mg/kg/i.p on 7th day) and DOX + THQ (10 mg/kg/day/i.p and DOX 15 mg/kg/i.p on 7th day). At the end of the experiment, liver tissues were extracted and evaluated histopathologically. eNOS, iNOS and Cas-3 immunostaining were performed to determine the expression levels. TUNEL method was used to determine apoptotic index. Furthermore, liver tissue total antioxidant status (TAS), total oxidant status (TOS), TNF-α and TGF-β levels were measured by ELISA assay. The DOX group showed histopathological deterioration compared to Control group. Moreover, apoptotic index, eNOS, iNOS and Cas-3 expressions increased in DOX group. While TAS level of the DOX group decreased, TOS level increased. TNF-α and TGF-β levels increased in DOX group. However, there was improvement in DOX + THQ group compared to DOX group. Moreover, apoptotic cell number, eNOS, iNOS and Cas-3 expressions decreased in DOX + THQ group compared to DOX group. We concluded that thymoquinone can be used as a phytotherapeutic for reducing DOX-induced liver damage.  相似文献   
10.
A new dagger nematode, Xiphinema tica n. sp., is described and illustrated from several populations extracted from soil associated with several crops and wild plants in Costa Rica. The new dagger nematode is characterised by a moderate body size (3276–4240 μm), a rounded lip region, ca 13.5 μm wide, separated from body contour by a shallow depression, amphidial fovea large, stirrup-shaped, a moderately long odontostyle ca 135 μm long, stylet guiding ring located at ca 122 μm from anterior end, vulva almost equatorial (50–54%), well-developed Z-organ, with heavy muscularised wall containing in the most of specimens observed two moderately refractive inclusions variable in shape (from round to star-shaped), with uterine spines and crystalloid bodies; female tail short, dorsally convex-conoid, with rounded end and a small peg, with a c’ ratio ca 0.8, bearing two or three pairs of caudal pores and male absent. The unique and novel uterine differentiation based on the coexistence of a well-developed Z-organ mixed with uterine spines and crystalloid bodies in Xiphinema prompted us to update and include this combination of characters in the polytomous key of Loof and Luc (1990). Integrative diagnosis was completed with molecular data obtained, using D2-D3 expansion segments of 28S rDNA, ITS1-rDNA, partial 18S–rDNA and the partial mitochondrial gene cytochrome c oxidase subunit 1 (coxI). The phylogenetic relationships of this species with other Xiphinema spp. indicated that X. tica n. sp. was monophyletic to the other species from the morphospecies Group 4, Xiphinema oleae.  相似文献   
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