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171.
172.
T. HytÖnen P. Palonen K. Mouhu O. Junttila 《The Journal of Horticultural Science and Biotechnology》2013,88(3):466-471
SummaryWhen strawberries (Fragaria ananassa Duch.) are produced in a greenhouse, usually two crops a year are obtained; in the fall and in the spring. To increase productivity, new cultivation techniques are needed. The aim of this study was to examine the effect of daylength treatments on the performance of strawberry plants to improve plant production protocols. The possibility of obtaining two successive crops during forcing was explored by exposing plants of cultivar Korona to two successive short day (SD) treatments followed by cold storage. The following daylength treatments were studied: 3 wk SD + 2 wk long day (LD) + 3 wk SD (3SD2LD3SD), 3 wk SD + 4 wk LD + 3 wk SD (3SD4LD3SD), and 10 wk SD (10SD). In addition, crown branching was studied in plants subjected to SD treatments. Two successive SD treatments enabled two successive flowering and cropping periods during greenhouse forcing after eight weeks of cold storage.The first SD treatment caused crown branching and induced flowering in the apical meristem of the main-crown and in the oldest axillary meristem(s), whereas younger axillary meristems were induced during the second SD treatment. Marketable yield and the number of inflorescences were comparable in 3SD4LD3SD and 10SD, but considerably lower in 3SD2LD3SD. However, this study demonstrated the high cropping potential of artificially SD treated plants, which makes them a potential alternative for greenhouse strawberry cultivation. Multi-crowned plants of ‘Korona’ can be produced by subjecting young plants to a three week SD treatment, and crown branches can be induced to flowering by a new SD treatment resulting in a very high cropping potential. Induced plants can be stored at –1°C for later forcing. 相似文献
173.
Lihui Xu Sabine Ravnskov John Larsen R. Henrik Nilsson Mogens Nicolaisen 《Soil biology & biochemistry》2012
Soil fungi and oomycetes (syn. peronosporomycetes) are the most common causes of pea diseases, and these pathogens often occur in complexes involving several species. Information on the dynamics within this complex of pathogens, and also between the complex of pathogens and other fungi in the development of root disease is limited. In this study, next-generation sequencing of nuclear ribosomal internal transcribed spacer-1 was used to characterize fungal communities in agricultural soils from nine pea fields, in which pea roots showed different degrees of disease. Fungal species richness, diversity, and community composition were analyzed and compared among the different pea soils. After filtering for quality and excluding non-fungal sequences, 55,460 sequences clustering into 434 operational taxonomic units (OTUs), were obtained from the nine soil samples. These sequences were found to correspond to 145–200 OTUs in each soil. The fungal communities in the nine soils were strongly dominated by Ascomycota and Basidiomycota. Phoma, Podospora, Pseudaleuria, and Veronaea, at genus level, correlated to the disease severity index of pea roots; Phoma was most abundant in soils with diseased plants, whereas Podospora, Pseudaleuria, and Veronaea were most abundant in healthy soils. No correlation was found between the disease severity index and the abundance of some of the other fungi and oomycetes normally considered as root pathogens in pea. 相似文献
174.
Tarlinton RE Yon L Klisch K Tötemeyer S Gough KC 《Journal of veterinary medical education》2011,38(3):305-310
Problem-based or case-based learning is a popular method of instruction in clinical degrees such as veterinary science, nursing, and medicine. It is difficult, however, for students to adapt to this learning method, and this difficulty has been well described. The present study surveyed first-year undergraduate veterinary students at the University of Nottingham about the challenges they faced upon beginning problem-based learning sessions. A surprisingly large percentage of students (36% of females and 38% of males) reported a lack of confidence in speaking in front of the other students as a concern they experienced during their first term. Conversely, only 10% of the female students (and none of the male students) reported overconfidence as a problem. This is in contrast to the perceptions of the staff members who facilitated the sessions who reported that 14% of the students exhibited underconfidence and 14% exhibited overconfidence. The difference between the female and male students' responses as well as the difference between the perceptions of students and those of facilitators is statistically significant (G-test p<.05). 相似文献
175.
S Gür G Türk E Demirci A Yüce M Sönmez Ş Özer EH Aksu 《Reproduction in domestic animals》2011,46(2):289-295
The aim of this study was to determine the changes in diameter of corpus luteum (CL), maternal progesterone (P) concentration, lipid peroxidation and non‐enzymatic antioxidant levels along with enzymatic antioxidant activities in pregnant ewes bearing single and twin foetuses. The ewes were selected from healthy animals that were brought to the abattoir for slaughtering. The ewes were divided into three groups: Group 1 (non‐pregnant, non‐oestrous, n = 30), Group 2 (pregnant bearing a single foetus, n = 30) and Group 3 (pregnant bearing twin foetuses, n = 12) after they were slaughtered. Pregnant ewes were in the first half of the pregnancy. The diameter of CL and P concentration of pregnant ewes bearing a single foetus or twin foetuses were found higher than that found in non‐pregnant ewes. Similarly, the P concentration of pregnant ewes bearing twin foetuses was higher than that found in pregnant ewes bearing a single foetus. Malondialdehyde (MDA) level in pregnant ewes bearing twin foetuses was higher than that found in both non‐pregnant and pregnant ewes bearing a single foetus. The serum glutathione (GSH) level and glutathione‐peroxidase (GSH‐Px) activity of pregnant ewes bearing twin foetuses were found lower than that found in non‐pregnant ewes. Additionally, the GSH‐Px activity of pregnant ewes bearing twin foetuses was found lower than that found in pregnant ewes bearing a single foetus. No significant difference was found between pregnant ewes bearing female and male foetus with respect to diameter of CL, P concentration and oxidative stress parameters. There were significant positive correlations between foetal number (0, 1, 2) and diameter of CL, P concentration, MDA level, and between P concentration and diameter of CL, MDA level. However, significant negative correlations were found between foetal number (0, 1, 2) and GSH level, GSH‐Px activity, and between P concentration and GSH‐Px activity. In conclusion, the diameter of CL enlarges, P production increases and oxidant/antioxidant balance impairs because of the gestation stress in ewes during pregnancy. 相似文献
176.
Krautwald-Junghanns ME Ellerich R Mitterer-Istyagin H Ludewig M Fehlhaber K Schuster E Berk J Dressel A Petermann S Kruse W Noack U Albrecht K Bartels T 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(1-2):8-16
Within the framework of a cooperative research project, turkey health as well as numerous aspects of animal welfare were examined in various intensive commercial farms with varying rearing forms. The present study demonstrates the prevalence of skin injuries concerning living animals as well as carcasses of slaughtered turkeys of both sexes. Although all turkeys were debeaked, prevalences of skin injuries at a value of 12.8% with male turkeys and 13.8% with female turkeys could be found at the age of 16 weeks. Within the scope of medically inspections skin injuries were mainly established in the head region, especially the snood as well as in the region of the back. By means of their clinical picture pecking wounds and scratch injuries could be distinguished. Skin lesion produced primary as a result of scratching the skin surface, could be enlarged by the animal itself or by conspecifics by beak pecking, especially after bleeding, in spite of debeaked upper beak. Injuries in the head region, especially of the snood, could be explained mainly as a result of pecking by conspecifics by reason of their clinical picture and were found mainly in male turkeys. Skin injuries in the region of the back, especially at the coxal tuberosity, were identified primarily as scratch marks. They were found mainly in female turkeys. A statistically significant correlation of the injury prevalence to particular husbandry parameters discussed in the literature as "predisposing" or "limiting" factors (e.g., population density, light regime or offer of employment material) could not be established in this study. At the meat inspection fresh scratching injuries at the chest and the hind legs were diagnosed most often. Especially fresh injuries of the carcass point to a misguided behaviour of the staff concerning animal handling during loading and transport which is not conform to animal welfare. 相似文献
177.
Sutor A Schwarz S Conraths FJ 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(11-12):457-464
Some invasive wildlife species have the potential to act as additional host and vector species for parasitic and other infectious diseases. We used the raccoon dog (Nyctereutes procyonides), a carnivore species that has its origin in Asia, as an example to demonstrate biological and ecological prerequisites which enables an invasive species to occupy a new habitat permanently. Studies conducted during the last ten years identified a total of 23 endoparasites, two ectoparasites, six bacterial or protozoan species and five viruses, found in the Nyctereutes procyonoides ussuriensis subspecies in its newly occupied range or in N. procyonoides koreensis in its original range. Results of studies in Finland and Germany furthermore showed that biological characteristics of the raccoon dog make this carnivore an appropriate host or vector for a variety of parasites and infectious diseases. This may result in a growing importance of this invasive carnivore for the epidemiology of transmissible diseases in Germany. Especially with regard to zoonotic disease outbreaks, the raccoon dog should therefore be paid more attention in disease prevention and eradication strategies. 相似文献
178.
Zorn J Schwamberger S Panzer W Adler H Kolb HJ 《Veterinary immunology and immunopathology》2011,144(1-2):27-35
Human leukocyte antigen (HLA)-haploidentical stem cell transplantation is an opportunity for nearly all patients lacking an HLA matched stem cell donor. However, graft rejection and graft-versus-host disease (GvHD) as well as infectious complications still result in high treatment-related mortality. Here, we used the dog as a preclinical model for the study of tolerance induction with the aim to optimize and to improve a clinical protocol of haploidentical stem cell transplantation. For this purpose CD6-depleted peripheral blood stem cells (PBSCs) were transfused 6d after transplantation of unmodified bone marrow from dog leukocyte antigen (DLA)-haploidentical littermate donors in order to induce immune tolerance. Besides hematopoietic stem cells CD6-depleted PBSC contain, NK cells and a minority of suppressive CD8-positive cells that may suppress activated T lymphocytes. Recipients were conditioned with, cyclophosphamide and antithymocyte globulin (ATG) preceded by a transfusion of donor buffy coat and either 1, 2 or 3 × 3.3 Gy total body irradiation (TBI). Postgrafting immunosuppression was limited to 30 d of cyclosporine and methotrexate. The additional administration of CD6-depleted PBSCs after unmodified marrow could not prevent GvHD, but it may improve engraftment and chimerism after conditioning with 2 × 3.3 Gy TBI. Reasons for incomplete suppression and possible improvements for clinical applications are discussed. 相似文献
179.
Hanno Zielke Thomas-Benjamin Seiler Sabine Niebergall Erik Leist Markus Brinkmann Denise Spira Georg Streck Werner Brack Ute Feiler Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2011,11(2):352-363