Pathogenicity of Heterobasidion annosum (Fr.) Bref. sensu stricto on coniferous tree species in Turkey

Two‐year‐old seedlings of Pinus brutia, P. brutia var. eldarica, Pinus pinea and 3‐year‐old seedlings of Pinus radiata, Pinus sylvestris, Pinus nigra and Cedrus libani were inoculated on the lower stem with isolates of Heterobasidion annosum s.s. collected from the Black Sea and Mediterranean regions of Turkey. In total, 315 seedlings were inoculated in April 2014 and incubated in a growth chamber for 7 weeks at 18–20°C. All isolates were pathogenic on the seven different hosts and had the ability to grow in living sapwood. The isolates had a greater growth on C. libani, P. sylvestris and P. radiata seedlings compared to plants of the other species tested. The least affected species were P. brutia and P. nigra. The isolates originating from the Black Sea region caused longer lesions on the hosts. Overall mortality during 7 weeks of incubation was 4%.     

Effects of melatonin on islet neogenesis and beta cell apoptosis in streptozotocin-induced diabetic rats: an immunohistochemical study

This investigation was carried out to explore the antidiabetic, antiapoptotic and neogenetic effects of melatonin (MLT) in streptozotocin-induced diabetic rats. Sixty-four male rats were assigned randomly to one of four groups for periods of 21 and 42 d as follows; i) control, ii) MLT, iii) diabetic (DM), and iv) DM + MLT. Immunohistochemical methods were used -with pancreatic tissue to determine the intensity of insulin, caspase-3 and Bcl-x(L) immune reactivities, and new islet formation. In untreated DM rats, BW loss, increased plasma glucose and MLT concentrations, as well as cytoplasmic degranulation and vacuolization were observed. We also observed a marked increase in the number of apoptotic caspase-3 positive cells and a few insulin- positive cells, but not antiapoptotic Bcl-x(L) positive cells. Observations in the DM + MLT-treated group revealed a high intensity of insulin- and antiapoptotic Bcl-x(L) immune reactivities at 21 and 42 d. Moreover, data indicated that MLT may cause beta cell proliferation and that new small islets originate from cells associated with ductal epithelium and from centroacinar cells by day 21. These data indicate that; i) MLT treatment may stimulate neogenesis in the pancreas of diabetic rats, and ii) MLT's antiapoptotic action may increase beta cell differentiation and caspase-3 inactivation or Bcl-x(L) activation.     

Thermodynamics and sorption characteristics of Zn(II) onto natural and chemically modified zeolites for agricultural and environmental using

Zeolites with high porous and cation exchange capacity have been widely used for agricultural and environmental purposes. This study was conducted to assess the thermodynamics and sorption characteristics of chemically modified zeolite (CMZ) from obtained natural zeolite (NZ), and to compare its properties. At first step of the sorption experiment, effects of pH, slurry concentration, stirring time, and heat on Zn removal were determined. Linear Langmuir isotherm was well fitted to data, and maximum sorption capacities (q _max) were calculated as 20.87 and 33.44 mg/g for NZ and CMZ, respectively. Dubinin-Redushkevich (D-R) isotherm showed that the adsorption process was probably controlled by chemical ion-exchange mechanism. The solubility of zinc DTPA should be so directly related to the model of D-R model. Therefore, zeolites can be used as carrier Zn in soils with insufficient zinc arid and semiarid regions. Enthalpy (ΔH°) and entropy (ΔS°) values were positive. The change values of Gibbs free energy (ΔG°) illustrated that the sorption of Zn ions onto zeolites was feasible and spontaneous. From the obtained results, it could be concluded that chemical modification increased q _max value of NZ, and the findings indicate clearly the possibility of using NZ and CMZ as Zn carrier in agricultural and also environmental treatments.     

Armillaria ostoyae in managed coniferous forests in Kastamonu in Turkey

Although several Armillaria species have been reported in Turkey, there is little information about their ecology in Turkish forests. In this study, we investigated five forest stands, approximately 5–74 ha in size, in Kastamonu province in the Black Sea Region of Turkey for the presence of Armillaria species in stumps and logs. The stands were mixed Abies nordmanniana ssp. bornmülleriana and Pinus sylvestris forests managed using a selective cuttings system; the proportion of fir in the total number of stems and stumps ranged from 36 to 98%. Based on sequence analysis of the internal transcribed spacer and intergenic spacer regions of the rDNA, all rhizomorphs sampled from the stumps and logs were of Armillaria ostoyae. The size of the genets was estimated with random amplified microsatellites analysis of the isolates and ranged from single stumps to approximately 450 m². One to seven genets were found in each stand. These results indicate that the genets had arisen from spores and vegetative spread was limited on most sites.     

Toxic Factor Produced by a Granulosis Virus in Armyworm Larva: Effect on Apanteles militaris

The internal parasitoid Apanteles militaris is affected by a proteinaceous toxic factor in the hemolymph of granulosis virus-infected armyworm larva. The hemolymph, after centrifugation to remove the virus particles and inoculation into the larval hemocoel, is still toxic to the parasitoids.     

Isolation of Dermatophilus congolensis from a cat

Dermatophilus congolensis was isolated from a cat with dermatitis. The isolate was sensitive to oxytetracyclin, streptomycin and penicillin but resistant to ampicillin, amoxicillin, gentamycin and cefoperazone.     

Adaptive significance of intermittent shoot growth in Douglas-fir seedlings

We tested the hypothesis that intermittent (lammas) shoot growth in Douglas-fir (Pseudotsuga menziesii var menziesii (Mirb.) Franco) seedlings from dry regions of southwest Oregon is adaptively significant. Seedlings from open-pollinated families (160 total) from two inland (dry) and two coastal (wet) sources were grown under either well-watered or intermittent drought conditions (temporary drought followed by rewatering) for two growing seasons. In the first growing season, the results supported the hypothesis: the frequency of a second flush was genetically controlled (although weakly, h(f) (2) 相似文献   

Effects of medetomidine and xylazine on intraocular pressure and pupil size in healthy Beagle dogs

ObjectiveTo determine the effects of intramuscular (IM) administration of medetomidine and xylazine on intraocular pressure (IOP) and pupil size in normal dogs.Study designProspective, randomized, experimental, crossover trial.AnimalsFive healthy, purpose-bred Beagle dogs.MethodsEach dog was administered 11 IM injections of, respectively: physiological saline; medetomidine at doses of 5, 10, 20, 40 and 80 μg kg⁻¹, and xylazine at doses of 0.5, 1.0, 2.0, 4.0 and 8.0 mg kg⁻¹. Injections were administered at least 1 week apart. IOP and pupil size were measured at baseline (before treatment) and at 0.25, 0.50, 0.75, 1, 2, 3, 4, 5, 6, 7, 8 and 24 hours post-injection.ResultsA significant decrease in IOP was observed at 6 hours after 80 μg kg⁻¹ medetomidine compared with values at 0.25 and 0.50 hours, although there were no significant changes in IOP from baseline. In dogs treated with 8.0 mg kg⁻¹ xylazine, significant reductions in IOP were observed at 4 and 5 hours compared with that at 0.25 hours after administration. In dogs treated with 5, 10, 20 and 40 μg kg⁻¹ medetomidine and 0.5, 1.0 and 2.0 mg kg⁻¹ xylazine, there were no significant changes in IOP. Pupil size did not change significantly after any of the medetomidine or xylazine treatments compared with the baseline value.Conclusions and clinical relevanceLow or moderate doses of medetomidine or xylazine did not induce significant changes in IOP or pupil size. In contrast, high doses of medetomidine or xylazine induced significant changes up to 8 hours after treatment, but values remained within the normal canine physiological range. The results of this study suggest a lack of significant change in IOP and pupil size in healthy dogs administered low or moderate doses of xylazine or medetomidine.     

Summer cover crops for weed management and yield improvement in organic lettuce (<Emphasis Type="Italic">Lactuca sativa</Emphasis>) production

Over the last two decades, the demand for organic products has grown rapidly in the world due to increased concern about side effects of pesticides on the environment and human health. Studies were conducted in organic lettuce (Lactuca sativa L.) from 2004 to 2005 at the Black Sea Agricultural Research Institute in Samsun, Turkey, to determine the suppressive effects of summer cover crops on weeds. The experiment was arranged in a randomized complete block design with four replications. Treatments consisted of grain sorghum [Sorghum bicolor (L.) Moench.], sudangrass [Sorghum vulgare Pers. var. sudanense (Piper) Hitchc.], hairy vetch (Vicia villosa Roth.), grain amaranth (Amaranthus cruentus L.), pea (Pisum sativum L.) and bare ground with no cover crop. Weed density and total weed dry biomass were assessed before and at 14, 28, and 56 days after incorporation (DAI) of the cover crops. The cover crops produced between 1.2 and 3 t ha⁻¹ biomass and grain sorghum produced more dry matter than any other species in both years. After incorporation of the cover crops, hairy vetch and sorghum treatments showed fewer weed species, and lower weed density than the other cover crops in both years. Hairy vetch, grain sorghum, and sudangrass were the most effective cover crops and reduced total weed dry biomass by 90.3%, 87.4%, and 86.9% in 2004, and by 88%, 86.3%, and 85.2% in 2005, respectively. Cover crop residue suppressed many broadleaved weed species but failed to control grass weeds. Hairy vetch treatments produced the highest yield, followed by sudangrass and grain sorghum. Yields with grain amaranth and pea were similar to that of the control. These results indicate that hairy vetch, grain sorghum, and sudangrass can be used to suppress weeds in early season of organic lettuce production.     

Biological control potential of Turkish entomopathogenic nematodes against the Mediterranean fruit fly <Emphasis Type="Italic">Ceratitis capitata</Emphasis>

The entomopathogenic nematodes Steinernema weiseri, S. feltiae, S. carpocapsae and two strains of Heterorhabditis bacteriophora, isolated from Turkish soils, were evaluated against larvae of the Mediterranean fruit fly (medfly) Ceratitis capitata in plastic cups under laboratory conditions with sandy loam soil and 10% moisture level. At a rate of 100 infective juveniles (IJs)/cm², the last instar larvae of C. capitata were susceptible to the entomopathogenic nematodes: the S. feltiae 09-31 strain recovered from Aydin provided 78% mortality, whereas S. weiseri and S. carpocapsae killed 50% and 56% of the larvae, respectively. Both strains of H. bacteriophora species caused less than 50% mortality. Except for S. feltiae, the majority of infected medflies died as prepupae or pupae within the puparia. More than 90% larval mortality was recorded at 200 and 400 IJs/cm² for S. feltiae. None of the nematode isolates infected the medfly pupae within the puparia. In pot experiments containing soil, S. feltiae caused 96% and 97% mortality at 100 and 200 IJs/cm², respectively. In pot experiments with grass present, more than 94% mortality was obtained in the presence of grass roots.