387,263 research outputs found
Spontaneous gene flow and population structure in wild and cultivated chicory, Cichorium intybus L.
No full textSpontaneous gene flow between wild and cultivated chicory, Cichorium intybus L., may have implications for the genetic structure and evolution of populations and varieties. One aspect of this crop-wild gene flow is the dispersal of transgenes from genetically modified varieties, e.g. gene flow from GM chicory to natural chicory could have unwanted consequences. With the purpose to identify and quantify crop-wild gene flow in chicory, we analysed introgression in 19 wild chicory populations and 16 accessions of chicory varieties and landraces distributed across Northern, Central and Mediterranean Europe. The analysis used 281 AFLP markers and 75 SSAP markers giving a total of 356 polymorphic markers. Results from model based assignments with the program STRUCTURE indicated many incidents of recent gene flow. Gene flow was observed both between cultivars and wild populations, between landraces and wild populations, between different wild populations as well as between cultivars. Population structure visualized by distance-based clustering showed a North–South geographical structuring of the wild populations, and a general grouping of the cultivars corresponding to known origin. The results indicated, however, that the structuring between the two groups of wild and cultivated types was weak. As crop and wild recipients are genetically close and genes are transferred between the two types rather frequently, focus on mitigating crop-wild gene flow should be increased, before transgenic varieties are cultivated openly
Über Schauspiele und Schaustellungen in Regensburg / von P. Wild
No full textÜBER SCHAUSPIELE UND SCHAUSTELLUNGEN IN REGENSBURG / VON P. WILD
Über Schauspiele und Schaustellungen in Regensburg / von P. Wild (1)
Cover (1)
Titelseite (2)
Illustration (4)
I. Quellen. (5)
II. Schauspiele und Schaustellungen in älterer Zeit bis 1748. (6)
III. Das Schauspiel an den Schulen. (37)
IV. Das Theater unter der Ägide des fürstlich Thurn- und Taxis'chen Hauses. (55)
V. Versuche ein selbständiges Theater zu gründen. (95)
VI. Von Erbauung des Theatergebäudes (Neues Haus) unter dem ... (107)
VII. Neuorganisation des Theaters als Aktienunternehmen. (126)
VIII. Das Theater als städtische Anstalt. (130
Vorstellung verschidener Chrono-Magischen Quadraten : Deren die erste Zehen von 25 Fächlein, und folgende Vier von 49 Fächlein, so man aufwerts, über die Seiten, und auch NB. über das Creutz (nemlich von A zum D, und vom B bis C) addirt, oder summiert, machen sammentlich 184. mahl das letzlich verflossene Jubel-Jahr aus, nemlich 1750. ...
No full textEntworffen Von P. Friderico Wild, p. t. Procuratore Ord. Min. S. Francisci Conv
Competition between wild and captive-bred Penaeus plebejus and implications for stock enhancement
No full textThe mechanisms that drive density dependence are rarely studied in the applied context of population management. We examined the potential for competition for food and shelter and the resulting demographic density dependence to influence how well populations of the eastern king prawn Penaeus plebejus Hess can recover following marine stock enhancement programmes in which captive-bred juveniles are released into the wild. Specifically, manipulative laboratory experiments were used to quantify the differential effects of competition for food and competition for shelter on survival of wild and captive-bred P. plebejus as densities were increased and as each category of P. plebejus (wild or captive-bred) was supplemented with the alternate category. Increasing population densities when food and shelter were limited lowered survival for both categories. When food was limited, survival of both categories was unaffected by addition of the alternative category. Adding wild P. plebejus to their captive-bred counterparts when shelter was limited under laboratory conditions resulted in significantly higher mortality in captive-bred individuals. In contrast, adding captive-bred P. plebejus to wild individuals under these conditions did not affect wild P. plebejus. We conclude that if the current results can be extended to wild conditions, competition for shelter may lead to the loss of captive-bred P. plebejus, thereby reducing the intended outcomes of stock enhancement. This highlights the importance of investigating interactions between wild and captive-bred animals prior to stock enhancement to predict long-term outcomes and identify situations where stock enhancement could be an effective response to the loss of populations or recruitment limitation
Ethnobotanical investigation of 'wild' food plants used by rice farmers in Kalasin, Northeast Thailand
No full textAbstract Background Wild food plants are a critical component in the subsistence system of rice farmers in Northeast Thailand. One of the important characteristics of wild plant foods among farming households is that the main collection locations are increasingly from anthropogenic ecosystems such as agricultural areas rather than pristine ecosystems. This paper provides selected results from a study of wild food conducted in several villages in Northeast Thailand. A complete botanical inventory of wild food plants from these communities and surrounding areas is provided including their diversity of growth forms, the different anthropogenic locations were these species grow and the multiplicity of uses they have. Methods Data was collected using focus groups and key informant interviews with women locally recognized as knowledgeable about contemporarily gathered plants. Plant species were identified by local taxonomists. Results A total of 87 wild food plants, belonging to 47 families were reported, mainly trees, herbs (terrestrial and aquatic) and climbers. Rice fields constitute the most important growth location where 70% of the plants are found, followed by secondary woody areas and home gardens. The majority of species (80%) can be found in multiple growth locations, which is partly explained by villagers moving selected species from one place to another and engaging in different degrees of management. Wild food plants have multiple edible parts varying from reproductive structures to vegetative organs. More than two thirds of species are reported as having diverse additional uses and more than half of them are also regarded as medicine. Conclusions This study shows the remarkable importance of anthropogenic areas in providing wild food plants. This is reflected in the great diversity of species found, contributing to the food and nutritional security of rice farmers in Northeast Thailand.</p
Preventing wild boar "Sus scrofa" damage - considerations for wild boar management in highly fragmented agroecosystems
No full textDuring the last three decades wild boar populations have grown rapidly and the range of the species has increased steadily, covering almost the whole European continent today. The huge spread of the wild boar and the high population densities pose major problems, particularly to agriculture. Wild boars cause considerable damage to fields and grassland, but also pose a potentially high threat to livestock, as carrier of the pathogen of the classical swine fever, which may be transmitted to domestic pigs and can cause huge losses. To prevent economic problems by high wild boar populations, an effective wild boar management has to be established. Besides the regulation of the populations by means of hunting, vulnerable crop fields have to be protected adequately. Crop protection is usually achieved by the use of electric fences. Alternatively, various methods are available that claim effective deterrence of wild boars, however, most of which lacking scientific proof of effectiveness.
This thesis, based on a field study conducted in the Canton Basel-Land, northwestern Switzerland, presents research results on the effectiveness of three different deterrent systems: solar-powered blinkers, an odour repellent, and a gustatory repellent. The aims of the study were: (1) to investigate three means to deter wild boars from agricultural land representative for other deterrents based on optic, olfactory, or gustatory effects; (2) to provide relevant and evidence-based data, which contribute to the policy and practice of wild boar management and damage prevention in the Canton Basel-Land, also applicable to other regions. I discussed the results in a broader context, also considering the role of hunting in damage prevention.
Solar blinkers and the odour repellent, which were investigated at baited luring sites, reduced the probability of wild boar visits by 8.1% and by 0.4% respectively. Both deterrents were not effective in preventing wild boars from accessing the lure food. Additionally, we did not find any initial deterrence effect. The gustatory repellent, which was investigated in experimental fields, did not have a significant effect on the frequency of damage events. Although we observed a slight trend towards a damage reduction, the results show, that the repellent was not able to prevent damage. We further could not detect any area avoidance by the wild boars as a response to the repellent.
The present study revealed, that none of the deterrents investigated was able to prevent wild boars from entering the experimental sites. Hence the deterrents in question are no effective means for field protection. Moreover, I suggest that any other deterrent basing on startling response, neophobia, fear-evocation, or conditioned avoidance would not be effective in preventing wild boars from entering agricultural land. To date, the only recommendable means for damage prevention is the electric fence, which should be taken into account by the responsible authorities. Based on the findings of the present study, farmers must be discouraged from the use of other deterrents than electric fences to protect their fields. Additionally, damage compensation should be subject to the condition of fencing of the fields.
Besides the protection of vulnerable crops the reduction of wild boar populations by means of hunting is crucial for damage prevention. Hunting rates have to be increased and hunting effort should focus on females of all age classes, but especially on juvenile females, which have shown to be highly reproductive and substantially contribute to population growth. For this purpose, selective hunting techniques like hide hunting and stalk hunting should be prioritised and promoted.
The highly reproductive wild boar possesses the ability to recover from population losses in a very short time. Hence, both effective hunting management and field protection will remain the most important tools for damage control. Further research is required to investigate and compare different wild boar management systems including also damage prevention under an economic perspective. Stakeholders like farmers, hunters, and authorities must be involved.
The omnivore wild boar is enabled to adapt to various environments. Wild boar populations are expected to increase further and to spread into areas not yet populated. In Switzerland, the spread into the central parts of the country will also be supported by additional wildlife crossings that are in construction or in process of planning which will pose a challenge for wildlife management in these regions
Biogenesis of multisubunit RNA polymerases
No full textGene transcription in the nucleus of eukaryotic cells is carried out by three related multisubunit RNA polymerases, Pol I, Pol II and Pol III. Although the structure and function of the polymerases have been studied extensively, little is known about their biogenesis and their transport from the cytoplasm (where the subunits are synthesized) to the nucleus. Recent studies have revealed polymerase assembly intermediates and putative assembly factors, as well as factors required for Pol II nuclear import. In this review, we integrate the available data into a model of Pol II biogenesis that provides a framework for future analysis of the biogenesis of all RNA polymerases
- …
