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1.
Composting is an environmentally sound method for the disposal of on-farm livestock mortalities that generates material suitable for use as fertilizer; however, this method is not generally permitted for disposal of transgenic livestock mortalities during the research and development phase. This study has explored the application of the polymerase chain reaction (PCR) as a method for assessing the persistence of transgene and mitochondrial DNA markers during the composting of euthanized transgenic pig. There was at least a 10(7) fold reduction of genetic material to a level that not either transgene or mitochondrion markers were detectable. At the end of the composting period, only bone fragments that were completely demineralised and chalky were detected. Chemically the compost was similar to that from pig litter and poultry mortalities, except the copper content was lower. Based on these data, composting appears to be an appropriate method for the disposal of transgenic animals.  相似文献   

2.
Although cultivation of genetic modified (GM) annual crops has been steadily increasing in the recent 10 years, the commercial cultivation of GM fruit tree is still very limited and reports of field trials on GM fruit trees are rare. This is probably because development and evaluation of GM fruit trees require a long period of time due to long life cycles of trees. In this study, we report results from a field trial on three rolB transgenic dwarfing apple rootstocks of M26 and M9 together with non-transgenic controls grafted with five non-transgenic scion cultivars. We intended to investigate the effects of transgenic rootstock on non-transgenic scion cultivars under natural conditions as well as to evaluate the potential value of using the rolB gene to modify difficult-to-root rootstocks of fruit trees. The results showed that all rolB transgenic rootstocks significantly reduced vegetative growth including tree height regardless of scion cultivar, compared with the non-transgenic rootstocks. Flowering and fruiting were also decreased for cultivars grown on the transgenic rootstocks in most cases, but the fruit quality was not clearly affected by the transgenic rootstocks. Cutting experiment and RT-PCR analysis showed that the rolB gene was stably expressed under field conditions. PCR and RT-PCR analyses displayed that the rolB gene or its mRNA were not detectable in the scion cultivars, indicating no translocation of the transgene or its mRNA from rootstock to scion. Our results suggest that rolB modified rootstocks should be used in combination with vigorous scion cultivars in order to obtain sufficient vegetative growth and good yield. Alternatively, the rolB gene could be used to dwarf vigorous rootstocks of fruit trees or produce bonzai plants as it can significantly reduce the vegetative growth of plants.  相似文献   

3.
Apple, peach and plum rootstocks were inoculated with the arbuscular mycorrhizal fungus Glomus sp. strain A6 on transplanting from in vitro to in vivo culture. The optimal root length for effective infection, assessed in apple rootstock M 25, was 0.1–1.5 cm, corresponding to the beginning of root elongation. When inoculated at this stage, plants showed maximal growth increase and survival. Mycorrhizal infection of the Mr. S. 2/5 rootstock induced earlier growth renewal after transplanting than in the controls. These results confirm previous reports that mycorrhizal inoculation, performed during transplantation from in vitro to in vivo culture, can enhance both the growth and the survival of plants.  相似文献   

4.
The rootstock effect on the fruit yield of a grafted tomato variety was genetically analyzed under salinity using as rootstock two populations of F(9) lines developed from a salt sensitive genotype of Solanum lycopersicum var. cerasiforme, as female parent, and two salt tolerant lines, as male parents, from S. pimpinellifolium, the P population (123 lines), and S. cheesmaniae, the C population (100 lines). There were rootstock lines from the two populations (up to 65% in the P population) that raised the fruit yield of the commercial hybrid under saline conditions. It is shown that this salt tolerance rootstock effect is a heritable trait (h (2) near 0.3), governed by at least eight QTLs. The most relevant component was the number of fruits. Thus most detected QTLs correspond to this component. In general, QTL gene effects are medium-sized, with contributions from 8.5 up to 15.9% at most, and the advantageous allele comes from the wild, salt tolerant species. Only two fruit yield QTLs on chromosomes P9 and C11 might correspond to fruit yield QTLs of the non-grafted lines indicating their root system dependence. A fruit yield QTL on chromosome 3 is acting epistatically in both populations. The epistatic interactions found were dominant and they were unveiled using the associated marker as cofactor in the composite interval mapping methodology. Therefore, an efficient and profitable utilization of wild germplasm can be carried out through the improvement of rootstocks that confer salt tolerance in terms of fruit yield to the grafted variety.  相似文献   

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7.
Concerns about invasions by novel bioenergy feedstocks are valid, given the parallels between the traits of energy crops and those of many common invasive plants. As the bioenergy industry is poised to introduce nonnative bioenergy crops to large acreages in the United States under state and federal mandates, it is important to consider these concerns – and not simply in an academic sense. Instead, the prevention of invasions should be codified in statutes and regulations pertaining to bioenergy production on both the state and federal level. Unfortunately, this is not occurring regularly or consistently at this time. The few existing regulations that do consider invasiveness in bioenergy systems suffer from vague terminology that could have major economic, environmental, and legal consequences. Here, we discuss existing regulatory challenges and provide solutions to address invasion potential of bioenergy crops. We provide model definitions and provisions to be included in revised or new state and federal regulations, including an invasion risk assessment process, a permit and bond system for high‐risk crops, and a risk mitigation provision for all novel crops. Our proposal provides a consistent and transparent system that will allow the industry to move forward with minimal risk of invasion by novel feedstocks.  相似文献   

8.
魏祥东  蓝崇钰  卢志菁  叶长明 《生态学报》2005,25(12):3301-3306
对T 4代转基因番木瓜进行了分子生物学和果实品质分析,结果表明,筛选获得的转基因番木瓜均为转番木瓜环斑病毒(PRV)复制酶突变体基因(RP),且对PRV抗性达到了高抗或免疫,RP基因在转基因植物中能稳定遗传至后代并在RNA水平上表达。在田间种植时,转基因木瓜的生长状况普遍好于普通番木瓜,尤其在生长后期(10月以后),普通番木瓜100%发病(大规模种植时),而大部分(约91.8%)转基因植株生长良好,果实较多且表面光洁、基本上无环斑。与非转基因亲本相比,T 4代转基因番木瓜的果实长度增加2.6%~5%,果实直径变小0.6%~1.5%,果肉厚度增加了12%~15%,因而果实形状与亲本相近或更好,且信用价值更高。转基因番木瓜果实中水分、蛋白质、氮、脂肪、还原性糖、维生素A、维生素C和类胡萝卜素的含量与对照都无显著性差异,即转基因番木瓜与亲本具有实质等同性,这表明转入的外源基因对番木瓜果实品质没有不良影响。  相似文献   

9.
Molecular biological characterization,fruit characters,and nutrients were analyzed for T4 generation of transgenic papaya.All transgenic papaya plants with the mutated replicase (RP) gene from papaya ringspot virus (PRSV) showed high resistance or immunity against PRSV in the field.The RP transgene can be steadily inherited to,and expressed at RNA level,the progenies.The growth characteristics of transgenic papaya were much better than nontransgenic papaya in the field.The non-transgenic papaya seedlings began to show typical symptoms caused by PRSV after being inoculated with PRSV.They died quickly and never grew to produce fruit.The adult trees developed yellow leaves and produced smaller fruits and were doomed to a slow death after some time,while most oftransgenic papaya plants (about 91.8%) did not show any symptoms caused by PRSV,and produced more,bigger,and high quality fruits.Compared with non-transgenic plants,the fresh fruit length of T4 generation of transgenic papaya increased 2.6%-5%,and the diameter decreased 0.6%-1.5%.The flesh thickness of fresh fruit increased 12%-15%,which made it fitter for eating.Although the fresh fruit quality changed,there was no significant difference between transgenic and non-transgenic papaya.The quality characteristics of dry fruit including the contents of water,lipid,N,protein,reduced sugar,vitamin A,vitamin C,and carotene in the T4 generation of transgenic papaya were all the same as their non-transgenic parents.This means that transgenic plants and non-transgenic plants are substantially equivalent,and the transgene has no effect on dry fruit quality.In this study,we found that vitamin A and vitamin C in red-fleshed papaya were 1.4-1.8 and 1.78-2.07 times more than the yellow-fleshed ones,respectively,while N and protein were only 84.2%-92.1% and 82.1%-98.9% of the yellow-fleshed ones.  相似文献   

10.
Molecular biological characterization, fruit characters, and nutrients were analyzed for T4 generation of transgenic papaya. All transgenic papaya plants with the mutated replicase (RP) gene from papaya ringspot virus (PRSV) showed high resistance or immunity against PRSV in the field. The RP transgene can be steadily inherited to, and expressed at RNA level, the progenies. The growth characteristics of transgenic papaya were much better than non-transgenic papaya in the field. The non-transgenic papaya seedlings began to show typical symptoms caused by PRSV after being inoculated with PRSV. They died quickly and never grew to produce fruit. The adult trees developed yellow leaves and produced smaller fruits and were doomed to a slow death after some time, while most of transgenic papaya plants (about 91.8%) did not show any symptoms caused by PRSV, and produced more, bigger, and high quality fruits. Compared with non-transgenic plants, the fresh fruit length of T4 generation of transgenic papaya increased 2.6%–5%, and the diameter decreased 0.6%–1.5%. The flesh thickness of fresh fruit increased 12%–15%, which made it fitter for eating. Although the fresh fruit quality changed, there was no significant difference between transgenic and non-transgenic papaya. The quality characteristics of dry fruit including the contents of water, lipid, N, protein, reduced sugar, vitamin A, vitamin C, and carotene in the T4 generation of transgenic papaya were all the same as their non-transgenic parents. This means that transgenic plants and non-transgenic plants are substantially equivalent, and the transgene has no effect on dry fruit quality. In this study, we found that vitamin A and vitamin C in red-fleshed papaya were 1.4–1.8 and 1.78–2.07 times more than the yellow-fleshed ones, respectively, while N and protein were only 84.2%–92.1% and 82.1%–98.9% of the yellow-fleshed ones. Translated from Acta Ecologica Sinica, 2005, 25(12): 3301–3306 [译自: 生态学报]  相似文献   

11.
Biopharmaceuticals make up a significant proportion of medicinal products used for the treatment of diseases such as cancer, arthritis, cardiac dysfunctions and AIDS. Access to therapies based on the use of these products has been limited as a result of the high marketing costs. Cuba has a biopharmaceutical industry with great potential for innovation, capable of developing new products and to produce others, like the biosimilars destined to fulfill the needs of its National Health System. The Center for State Control on the Quality of Drugs (CECMED) the Cuban NRA, is facing the challenge of regulating the approval of biosimilar products manufactured locally. Consequently, CECMED has issued a position paper establishing the basic principles for regulation of these products and a specific guideline on this was elaborated.  相似文献   

12.
Brazil has a biosafety law that was approved in 1995. This law provides for a horizontal type of regulation that coordinates other existing regulatory frameworks in the areas of agriculture, health and environment. Various federal government departments are responsible for implementing the law. The National Technical Biosafety Commission is the national competent authority on biosafety with overall responsibility. In the case of Bt plants or any insecticidal organism, the Agrochemical Law also applies and authorization for laboratory, greenhouse and field studies must be obtained from the Plant Protection Secretariat, the Brazilian Institute of Environment and the National Agency of Health. Furthermore, the National Environmental Council must issue a license for commercialization of any GMO. There is pressure needed for capacity building and to harmonize the regulatory and administrative frameworks among the different federal departments involved. Some perspectives and challenges for the commercial registration of transgenic crops are discussed.  相似文献   

13.
Experiments were carried out to evaluate the effects of 4/2 light-dark cycles (4 h of light followed by 2 h of dark) on the rooting responses of shoots cultivated in vitro of the fruit tree rootstocks GF 677 (peach × almond hybrid), Mr.S. 2/5 (Prunus cerasifera), MM 106 (apple Nothern Spy × Paradise M1) and BA 29 (Cydonia oblonga). Under this light regime rooting percentage of GF 677, Mr.S. 2/5 and MM 106 shoots reached 100 % as in the control treatment (16/8), while in BA 29 shoots, short light-dark cycles increased rooting response by about 65 %. Moreover, the shoots of all rootstocks submitted to the 4/2 cycle showed an appreciable increase in root number and length, and an earlier root emergence of about 4 – 5 d compared to the 16/8 cycle. Finally, rooting percentage of BA 29 shoots submitted to the 4/2 light regime and treated with 0.2 mg dm−3 indolebutyric acid (IBA), was equal to that reported with 0.4 mg dm−3 IBA under the 16/8 regime, indicating that the former light regime also amplified the rhizogenic effect of auxin.  相似文献   

14.
Characterization of the ColE1 mobilization region and its protein products   总被引:6,自引:0,他引:6  
Summary A third of the 6.6 kb genome of ColE1 is devoted to mobilization (mob) genes necessary to promote its specific transfer in the presence of conjugative plasmids. Themob region is genetically complex: twomob genes are entirely overlapped by a third. Oligonucleotide-directed mutagenesis was used to insert an amber codon into one of the overlapped genes and make possible a full complementation analysis ofmob. Fourmob genes essential for mobilization by R64drd11 were thus identified. Fragments ofmob were subcloned under control of the Ptac promoter in a suitable vector, overexpressed in minicells and the mobilization proteins visualized. A comprehensive alignment of themob region of ColE1 with those of its close relatives ColK and ColA demonstrating that the four essentialmob genes are conserved is also presented.  相似文献   

15.
Abstract

The effect of Azospirillum brasilense Sp245 on the micropropagation of three fruit rootstocks: Mr.S 2/5 plum (Prunus cerasifera×P. spinosa), GF 677 hybrid (Prunus persica×P. amigdalus), and MM 106 apple (Northen Spy×M1) was assessed. Rooted shoots were treated with 3×107 of Sp245 cells during transplantation from in vitro cultures to the acclimatization phase. After 60 days, growth parameters were positively affected by Sp245 inoculum. In the case of Mr.S 2/5, an increase in rootstock stem length and node number by 37% and 42%, respectively, compared to the control was noted. In the case of GF 677, the bacterial inoculum increased stem length and node number by up to the 75% and 65%, respectively, compared to the control. The inoculum did not exert on MM 106 for both parameters suggesting that the effects of Sp245 could depend on a specific clone-microbe association. In all cases, however, a higher vigor, consistent with a wider leaf area, was present in the inoculated plantlets demonstrating that the use of Azospirillum can significantly contribute to optimize plant performance during the phase of adaptation of plants to post-vitrum conditions.  相似文献   

16.
MOTIVATION: Our goal is to construct a model for genetic regulatory networks such that the model class: (i) incorporates rule-based dependencies between genes; (ii) allows the systematic study of global network dynamics; (iii) is able to cope with uncertainty, both in the data and the model selection; and (iv) permits the quantification of the relative influence and sensitivity of genes in their interactions with other genes. RESULTS: We introduce Probabilistic Boolean Networks (PBN) that share the appealing rule-based properties of Boolean networks, but are robust in the face of uncertainty. We show how the dynamics of these networks can be studied in the probabilistic context of Markov chains, with standard Boolean networks being special cases. Then, we discuss the relationship between PBNs and Bayesian networks--a family of graphical models that explicitly represent probabilistic relationships between variables. We show how probabilistic dependencies between a gene and its parent genes, constituting the basic building blocks of Bayesian networks, can be obtained from PBNs. Finally, we present methods for quantifying the influence of genes on other genes, within the context of PBNs. Examples illustrating the above concepts are presented throughout the paper.  相似文献   

17.
The aim of the present work was to evaluate the effects of water stress and different rootstocks on the quality indices and nutritional characteristics of peach fruit, cv. Suncrest. The results show how pre‐harvest factors, such as the type of rootstock and water stress, can influence the quality indices and nutritional properties of peach fruits. Rootstocks type influenced both quality indices such as flesh firmness (FF) and soluble solid content (SSC), but it is unclear how rootstock exerted its influence. Also water stress induced changes in quality indices of peach fruit grafted on GF 677 and Montclar whereas minor effects were recorded when water stress was applied on Penta. The content of hydroxycinnamic acids was similar in control fruits of GF677, Montclar and Penta and it increased significantly only in fruit of trees grafted on GF 677 following water stress. Anthocyanins content in fruit of control plants was higher in Montclar in comparison with the fruit grafted on the other two rootstocks while procyanidin content was higher in fruit of control plants grafted on Penta. Following the water stress an increase in total anthocyanins was observed in GF 677 and Penta whereas no significant differences were found for Montclar. Water stress induced a significant decrease in procyanidin content in Penta. In conclusion in fruits of trees grafted on Penta following water stress quality indices did not show changes but significant variations in some phytochemicals, i.e. anthocyanins and procyanindins were observed. The results suggest that the regulation of water management is an important factor to maintain a good quality of the fruits. In fact, if irrigation stress can induce a higher biosynthesis of phytochemical compounds and an increase of SSC, at the same time, it can change fruit quality traits, such as a lower FW in Montclar, a higher titratable acidity (TA) in GF 677 and Penta and a lower FF in Gf 677 and Montclar.  相似文献   

18.
The potato has tremendous potential as a transgenic crop and is a good model system by which to analyse metabolic regulation and gene expression. The potato’s difficult genetics, but ease of genetic transformation and its clonal means of propagation make it ideal for applied agricultural molecular genetics. Thus, the next 4 years promise to put the potato (with a diversity of transgenic constructs expressed) in the limelight as many of the first transgenic agricultural products enter the marketplace.  相似文献   

19.
Biotechnology affords opportunities to develop new tools to treat pest and disease problems. When a given pest or disease problem has no satisfactory cure or treatment, usually only a technological breakthrough can provide one, but the process whereby this happens can be undefined and unpredictable. Furthermore, it is difficult to predict which methods will work at the outset, meaning that it is also difficult for funding agencies to determine which proposals to support. When a proposed solution is new and may involve genetic manipulation, it may also be hard for the public, as represented by regulatory agencies, to accept. In addition, when the application market is small, funding is modest. When the problem is major but periodic, as in the case of migratory locusts, funding, interest and attention cannot be easily found, focused or sustained. It is only when a problem is severe and economically compelling, such as Pierce's Disease of grapevine in southern California, that it is possible to concentrate funding, attention and sustained interest long enough to have a chance of finding a lasting solution.  相似文献   

20.
Calling the tunes on transgenic crops: the case for regulatory harmony   总被引:1,自引:0,他引:1  
Genetically modified (GM) crops are now grown commercially in 23 countries, with another 29 granting approval for import and release into the environment. Despite the socio-economic and environmental benefits of the technology, further development is being hampered by differences in national regulatory frameworks relating to research, biosafety, and to the trade and use of GM crops. The biosafety regulations in different countries are based on five main international instruments that influence the development of national biosafety systems in terms of field trial permit requirements, risk assessment criteria, labeling, traceability, transparency, public awareness, post-monitoring and import regulations. The global harmonization of data collection, testing procedures and information exchange would help to remove artificial trade barriers, expedite the adoption of GM crops, foster technology transfer and protect developing countries from exploitation, instilling confidence and bringing the benefits of GM products to the consumer.  相似文献   

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