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81.
Potential for simultaneous improvement of grain and biomass yield in Central European winter triticale germplasm 总被引:1,自引:0,他引:1
Manje GowdaVolker Hahn Jochen C. ReifC. Friedrich H. Longin Katharina AlheitHans P. Maurer 《Field Crops Research》2011,121(1):153-157
Winter triticale, an abundant biomass source for producing biogas in Central Europe, has been bred until now for increased grain yield but not for early biomass yield. Therefore, our objectives were to assess the feasibility of breeding triticale for simultaneous improvement of early biomass and grain yield as well as to predict the early biomass yield using an index of traits measured at maturity stage. A representative sample of 100 triticale lines was evaluated in Experiment I at four locations in Germany. Traits were measured at two growth stages (early dough and full maturity). Genetic variances were significantly different from zero for all traits. The correlated response for early biomass yield estimated from grain yield (0.53) was high, which points to the efficiency of indirect selection. A multiple regression model was developed to predict early biomass yield. The reliability of the model was confirmed in an independent Experiment II with 49 lines. The calibration model explained 55% of total variation for early biomass yield. This clearly underlines that at least during earlier stages of selection, field testing can be carried out for grain yield and related traits to select potential genotypes with high biomass yield based on the developed regression model. 相似文献
82.
Sustainable development and sustainable forestry: analogies,differences, and the role of flexibility 总被引:2,自引:1,他引:1
Various approaches have been developed to achieve sustainability in forestry, under changing social needs and, consequently,
changing definitions of sustainability. This has led to the confusing situation in which various groups have different understandings
of the meaning of ‘sustainability’. Likewise, the concepts utilized to achieve sustainability, often with a poorly defined
objective, are sometimes not clear and/or inconsistent as a systematic overview regarding definitions and concepts is lacking.
Based on a literature review, this paper discusses related terms such as sustainability, sustained yield management, sustainable
forestry, sustainable forest management and sustainable development: their history, concepts and relationships, from a European
perspective. Finally, flexibility is proposed as a solution to overcome the identified shortcomings at all scales, while focussing
on the enterprise level. The origin of the sustainability concept in forestry was first driven by forest experts, while participatory
elements have been considered since the more recent idea of sustainable development. Since then, much effort has been made
to achieve intragenerational fairness by creating an improved participatory process. Concurrently, the original idea of sustainable
forestry as long-term and future-oriented management, considering future generations’ needs fell behind. An increasing standing
timber volume in Europe and the discussion on climate change brought new interest in how to cope with risks in the context
of pervasive future uncertainties within the scope of promoting sustainable development. Although the consideration of risk
has been concentrated on as a topic in forest science in recent years, studies have mainly focused on the enhancement of forest
resistance against disturbances. However, precaution and risk avoidance alone are probably insufficient to achieve an improved
sustainable development that focuses on intergenerational fairness, as these more defensive approaches may disregard important
management opportunities involved with an uncertain future. A perhaps more promising approach, the idea of future options
and the ability to respond to changing social and biophysical circumstances (i.e. flexibility) as criteria for sustainable
development have only shown a shadowy existence up to now. To further develop the consistency of sustainability concepts,
a shift of sustainability approaches from continuity towards flexibility options is proposed. 相似文献
83.
Wallace RJ Oleszek W Franz C Hahn I Baser KH Mathe A Teichmann K 《British poultry science》2010,51(4):461-487
1. Plants and their biologically active chemical constituents, sometimes called secondary metabolites or bioactives, present numerous opportunities for the improvement of livestock production by inclusion in the diet. 2. Many such plant derived materials have well established therapeutic values in man; however, their potential as feed additives in animal production, particularly of poultry, remains largely unexploited. 3. There is increasing evidence indicating that they can be efficient in controlling diseases, and plant bioactives may also influence production parameters such as feed efficiency and product quality. 4. It has been reported that they may even replicate some of the effects of antibiotic growth promoters, which were banned from use in Europe from 2006. 5. This review assesses the status of plant bioactives in poultry production and their mode of action on avian physiology, particularly in the digestive tract. 相似文献
84.
In the United States of America, Aujeszky's disease (pseudorabies) has been eradicated from all domestic swine. Some re-emergence of infection occurred as vaccine use diminished. Sporadic outbreaks have also occurred because of the reservoir of infection in feral swine that have spread across the southern two-thirds of the country and Hawaii. In order to be able to understand the origins of re-emerging virus, sequence analysis of variable genes in pseudorabies virus (PRV) has been used to differentiate strains. Most PRV from feral swine can be distinguished from virus circulating in domestic pigs during the national epizootic. However, several feral swine isolates of PRV from south central states are closely related or identical in sequence to strains from domestic pigs. Extensive study by PCR for the presence of virus in the oral cavity of feral pigs disclosed that the viral DNA is distributed widely in tonsils salivary glands, taste buds and even mucosa in the vicinity of tusks. Clearly the virus in feral swine has multiple mechanisms of transmission to insure persistent infection and the threat of re-emergence in domestic swine continues. 相似文献
85.
The successful development of phenology models from field studies depends on many factors, some of which are entirely under the control of pest managers. For example, one such factor is the choice of method for calculating thermal units. In this study, we have demonstrated that four methods for calculating thermal units provided for acceptable predictions of one phenological event of one insect species, while another method for calculating thermal units did not. The measure of central tendency (mean or median) that is used to estimate lower developmental temperatures and required thermal summations is another factor that pest managers can control when developing phenology models from field studies. Here, we show that predictions that were made when using phenology models based on median lower developmental temperatures and median required thermal summations were superior to predictions that were made when using phenology models based on mean lower developmental temperatures and mean required thermal summations. The use of bootstrap vs. non-bootstrap estimates of lower developmental temperatures and required thermal summations is yet another factor that pest managers can control when developing phenology models from field studies. In this study, we found that calculating and using bootstrap estimates of lower developmental temperatures and required thermal summations in phenology models did not improve the predictions of one phenological event for one insect species. The implications of these and other findings are discussed. 相似文献
86.
Truong LQ Kim JT Yoon BI Her M Jung SC Hahn TW 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(12):1597-1601
Brucella infections in wildlife originate either from contact with infected livestock or from a natural sustainable reservoir in wildlife populations. As South Korea has set a goal of brucellosis eradication by 2013, it is necessary to determine the prevalence of Brucella in wildlife and wild rodents. This information will play an important role in the control of brucellosis. Because of the absence of prominent clinical signs, direct and indirect laboratory tests are essential for diagnosing brucellosis. In this study, tissue and blood samples were taken from wild animals, abandoned dogs, a cat and wild rodents, and they were tested for Brucella or Brucella-specific antibodies by isolation, PCR and serology. Results showed that 18.6% (33/177) of blood samples were positive by PCR, and 5.7% (11/194) were positive by C-ELISA. However, none of these samples yielded culturable bacteria. Of the tissue samples, 9.7% (8/82) were positive by PCR. Brucella was isolated from only one tissue culture from a Chinese water deer carcass. This Brucella species was identified as Brucella abortus biovar 1 by biotyping, 16S rRNA PCR and the Bruce-ladder PCR assay. In this study, we reported the prevalence of Brucella in wildlife, dogs, a cat and rodents by using serological and molecular methods, and we report the first isolation of B. abortus in wild Chinese water deer in South Korea. 相似文献
87.
This report describes the clinical, ultrasonographic and radiographic findings in an 8‐year‐old Icelandic mare with unilateral shoulder luxation after general anaesthesia. Reduction of the luxated humerus was performed in a closed fashion using a calving jack under general anaesthesia. The horse recovered well and ultimately returned to its previous level of performance. 相似文献
88.
Araújo MM Marchioni E Bergaentzle M Zhao M Kuntz F Hahn E Villavicencio AL 《Journal of agricultural and food chemistry》2011,59(4):1244-1248
This study attempts to examine the folic acid stability after irradiation treatment, under different physical states, pH values, and atmosphere conditions. Aqueous folic acid samples, folic acid in powder, and wheat flour fortified with folic acid were irradiated by an electron beam (E-beam) between 0 (control) and 10.0 kGy. It was realized that the physical state of folic acid plays an important role on its stability toward E-beam processing, being largely unstable in solution, no matter the pH and atmosphere conditions assayed. Otherwise, folic acid in powder showed huge irradiation stability, even when mixed in a dry food matrix, such as fortified wheat flour samples. 相似文献
89.