Promoting microbial immobilization of soil nitrogen during restoration of abandoned agricultural fields by organic additions

Application of organic materials to soils to enhance N immobilization into microbial biomass, thereby reducing inorganic N concentrations, was studied as a management option to accelerate the reestablishment of the native vegetation on abandoned arable fields on sandy soils the Kiskunság National Park, Hungary. Sucrose and sawdust were used at three different topographic sites over 4 years. N availability and extractable inorganic N concentrations were significantly reduced in all sites. Soil microbial biomass C and microbial biomass N increased significantly following C additions, but the microbial C to microbial N ratio remained unaffected. It is concluded that the combined application of the rapidly utilized C source (sucrose) promoted N immobilization, whereas the addition of the slowly utilized C source (sawdust) maintained the elevated microbial biomass C and microbial biomass N in the field.     

Changes induced by powdery mildew in the salicylic acid and polyamine contents and the antioxidant enzyme activities of wheat lines

Investigations were made on four wheat (Triticum aestivum L.) lines under greenhouse conditions, in order to reveal the role of stress-protective materials, namely salicylic acid, polyamines and antioxidant enzymes in the level of tolerance to powdery mildew infection caused by Blumeria graminis (DC.) Speer f.sp. tritici ém. Marchal. The four lines showed different levels of tolerance, assessed on the Saari-Prescott scoring scale: TC26 and TC33 proved to be susceptible and TC9 and TC19 resistant. In most of the lines, infection caused changes in the activities of antioxidant enzymes, especially in the case of guaiacol peroxidase. Four peroxidase isoenzymes, which responded differently to powdery mildew infection could be detected by gel electrophoresis. Infection had only a slight effect on the levels of salicylic acid (free and bound forms) in inoculated plants; while the levels of polyamines, especially spermidine and spermine increased after infection. Correlation analysis was also performed to examine how close a relationship exists between the parameters investigated. It was concluded that salicylic acid, polyamines and antioxidant enzymes have an important role in plant responses and defence mechanisms during this biotic stress and that in some cases there were significant relationships between them. However the levels of these compounds either initially or after pathogen inoculation, could not explain the degree of tolerance to powdery mildew in the four wheat lines investigated.     

Effect of added barley chromosomes on the flowering time of new wheat/winter barley addition lines in various environments

The heading characters and morphological traits of two partial sets of wheat–barley disomic addition lines, namely Mv9kr1/Igri and Asakaze/Manas, were evaluated under controlled environmental conditions in a phytotron under long-day, short-day and non-vernalised conditions and in field-sown experiments. The winter barley chromosome additions significantly influenced the flowering time of wheat both in the controlled environment test and under field-sown conditions. Of all the barley addition lines, the effect of the 4H and 7H additions was the most characteristic. The 7H addition lines were the earliest in both cultivar combinations in each treatment. In the Mv9kr1/Igri combination the 4H addition was the latest under all the environmental conditions. In the Asakaze/Manas combination 4H addition was the latest under short-day and long-day illumination in the phytotron but the 6H addition was the latest without vernalisation and in the field in 2012. There was 12 and 11 days difference between the flowering times of the 7H and 4H Mv9kr1/Igri and Asakaze/Manas addition lines in the field in 2012, which increased to 52 and 44 days under short-day illumination in the phytotron. In the winter wheat background, the addition of 2H carrying the photoperiod sensitivity gene Ppd-H1 decreased the flowering time under the short photoperiod regime, but had a very strong delaying effect under field-grown conditions. Considering the yield components under field conditions, 4H was the most fertile of the addition lines, while 7H showed the highest tillering capacity, and Igri 3H had good tillering capacity and the highest number of seeds per plant.     

Effects of ketamine-xylazine intravenous bolus injection on cardiovascular function in rabbits

The direct effects of ketamine-xylazine (KET-XYL) on vascular function have not been investigated in rabbits. The short-term cardiovascular effects of intravenous (IV) KET-XYL bolus injection, therefore, should be investigated using vascular ultrasonography.In this prospective experimental study, KET-XYL anesthesia was induced IV in 9 female New Zealand White rabbits before 3 defined test bolus injections of KET-XYL were given IV. Before and for 10 min after each KET-XYL injection vascular and hemodynamic variables were recorded at the left common carotid artery (ACC) after the 1st injection, and at the abdominal aorta (AA) after the 2nd injection. Echocardiography was performed after the 3rd injection to investigate changes in cardiac parameters.Ketamine-xylazine IV caused a significant increase in vessel diameter at the ACC and AA. Average volumetric flow significantly decreased at the ACC and pulsatility index significantly decreased at the AA. Fractional shortening (FS) and heart rate significantly decreased, while mean arterial blood pressure initially increased.Bolus injections of KET-XYL IV produced a transient vasodilatation at the ACC and AA. Despite central vasodilatation, bradycardia, and decrease of FS and average volumetric flow (VFave), mean arterial blood pressure did not significantly decrease indicating well-preserved cardiovascular compensatory mechanism after the ratio and doses of KET-XYL IV bolus injections used in this study.     

Effects of urbanization on ground-dwelling spiders in forest patches,in Hungary

Effects of urbanization on ground-dwelling spiders (Araneae) were studied using pitfall traps along an urban-suburban–rural forest gradient in Debrecen (Hungary). We found that overall spider species richness was significantly higher in the urban sites compared to the suburban and rural ones. The increased diversity was due to the significantly more open-habitat species in the assemblages at the urban sites. This suggests that species from the surrounding matrix (grasslands and arable lands) penetrated the disturbed urban sites. The ratio of forest species was significantly higher in the rural sites than in the suburban and urban ones, suggesting that forest species are indeed sensitive to the disturbance caused by urbanization. Canonical correspondence analysis revealed that the species composition changed remarkably along the urbanization gradient. Open-habitat spiders were associated with the urban sites of higher ground and air temperature. Forest spiders were characteristic of the rural sites with higher amount of decaying woods. Our findings suggest that the overall diversity was not the most appropriate indicator of disturbance; species with different habitat affinity should be analyzed separately to get an ecologically relevant picture of the effect of urbanization.     

Improving the fertility of sandy soils in the temperate region by combined biochar and microbial inoculant treatments

Achieving a sustainable increase in the fertility of sandy soils is a major problem. The application of biochar (BC) is a relatively new method, but results for a temperate climate are scarce. This work investigates various combined doses of BC and plant growth-promoting rhizobacteria inoculants on the fertility of acidic and calcareous sandy soils, hypothesising that joint application could have a synergistic impact. The effects were followed by measuring chemical (pH, organic matter, nutrient availability) and microbiological properties of the soil and maize biomass. 30 t ha^?1 BC increased both pH (by 1 unit) and nitrification in acidic soil (causing a 60% drop in NH₄-N concentration), and the phosphorus and potassium availability (by 53 and 80%, respectively) in both soils. Substrate-induced respiration increased by up to 100% and 50% in acidic and calcareous soil, respectively, in treatments involving both BC and inoculant. In acidic soil a BC dose of 3 t ha^?1 resulted in a 70% decrease in arbuscular mycorrhizal fungal infection. Changes in maize grain yield were not significant, but the increase in above-ground biomass indicated that the combined application of BC and inoculant is more beneficial than separate application of these yield-increasing agents, primarily on acidic sand.     

Efficacy of Chondroprotective Food Supplements Based on Collagen Hydrolysate and Compounds Isolated from Marine Organisms

Osteoarthritis belongs to the most common joint diseases in humans and animals and shows increased incidence in older patients. The bioactivities of collagen hydrolysates, sulfated glucosamine and a special fatty acid enriched dog-food were tested in a dog patient study of 52 dogs as potential therapeutic treatment options in early osteoarthritis. Biophysical, biochemical, cell biological and molecular modeling methods support that these well-defined substances may act as effective nutraceuticals. Importantly, the applied collagen hydrolysates as well as sulfated glucosamine residues from marine organisms were strongly supported by both an animal model and molecular modeling of intermolecular interactions. Molecular modeling of predicted interaction dynamics was evaluated for the receptor proteins MMP-3 and ADAMTS-5. These proteins play a prominent role in the maintenance of cartilage health as well as innate and adapted immunity. Nutraceutical data were generated in a veterinary clinical study focusing on mobility and agility. Specifically, key clinical parameter (MMP-3 and TIMP-1) were obtained from blood probes of German shepherd dogs with early osteoarthritis symptoms fed with collagen hydrolysates. Collagen hydrolysate, a chondroprotective food supplement was examined by high resolution NMR experiments. Molecular modeling simulations were used to further characterize the interaction potency of collagen fragments and glucosamines with protein receptor structures. Potential beneficial effects of collagen hydrolysates, sulfated glycans (i.e., sulfated glucosamine from crabs and mussels) and lipids, especially, eicosapentaenoic acid (extracted from fish oil) on biochemical and physiological processes are discussed here in the context of human and veterinary medicine.     

ENVIRONMENTAL EFFECTS ON SYMPTOM EXPRESSIONS OF VIRUS DISEASES IN GRASSES

Viruss damage was observed on plants of Lolium perenne L. and Dactylis glomcrata L. undergoing growth-analysis studies. On the basis of visual symptoms the damage was presumed to be caused by barley-yellow-dwarf virus (BYDV) in ryegrass and by streak virus (CSV) in cocksfoot. The number of plants which could be clinically diagnosed as infected and the degree of damage were both positively correlated with temperature. It was inferred that at low temperatures both viruses could remain relatively inactive, or even latent. This was subsequently confirmed by removing cocksfoot plants from a heated glasshouse (19°–23°C) to a cold environment (6–10°C) which resulted in a progressive loss of symptoms in newly developing leaves. Some possible explanations and practical implications are briefly discussed.     

Long-term radiographic comparison of tibial plateau leveling osteotomy versus extracapsular stabilization for cranial cruciate ligament rupture in the dog

OBJECTIVE: Comparison of 2 methods of surgical management of cranial cruciate ligament (CCL) injury in large-breed dogs using a radiographic osteoarthrosis (OA) scoring system. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n=66). METHODS: Radiographs were evaluated from dogs weighing >/=22.7 kg, with surgical management of CCL rupture using extracapsular repair (ECR) or tibial plateau leveling osteotomy (TPLO). Radiographs were taken immediately before surgery and >/=12 months later. An OA score was assigned to each set of radiographs taken at the preoperative and final examinations by evaluating 32 specific features of stifle OA. The difference between preoperative and final OA scores were subtracted and 2 final score categories of a change 5 were created. A logistic regression model was used to evaluate the effect of right versus left pelvic limb, age, preoperative weight, postoperative weight, days from surgery until final radiographic recheck, cranial cruciate status at surgery, medial meniscus status at surgery, and ECR versus TPLO. RESULTS: The ECR group had 27 stifles (22 dogs) and the TPLO group had 52 stifles (44 dogs). ECR dogs had a preoperative weight of 33.4+/-9.3 kg (range 22.7-54.1 kg) and a preoperative OA score of 13.0+/-8.4 (range 1-34) compared with TPLO dogs that had a preoperative weight of 38.9+/-9.1 kg (range 25-63.9 kg) and preoperative OA score of 15.9+/-8.4 (range 4-44). Postoperative weights for ECR and TPLO dogs were 33.6+/-9 kg (range 21.8-54.6 kg) and 39.4+/-10.1 kg (range 24-72 kg), respectively. Final OA scores were: ECR dogs, 26.3+/-10.8 (range, 10-54); TPLO dogs, 23.3+/-9.5 (range, 12-50). Dogs with a final change in OA score of >/=6 were 5.78 times more likely to have had ECR compared with those that had TPLO as stabilization procedure (odds ratio=5.78; Log-likelihood test P-value=.025). Other dependent variables were not significant. CONCLUSIONS: Based on logistic regression analysis, dogs with larger OA score differences were 5.78 times more likely to have had ECR than TPLO. CLINICAL RELEVANCE: Prospective, randomized surgical trials with pre-defined objective measures would be required to further evaluate the clinical importance of these preliminary findings which suggest that TPLO may help stabilize the cranial tibial thrust as originally proposed.