35)The history of investigations of the genetic transformation of animal cells

In 1974 Rudolf Jaenisch created the first genetically modified animal by inserting a DNA virus into an early-stage mouse embryo and showing that the inserted genes were present in every cell.^[1] However the mice did not pass the transgene to their offspring. In 1981 the laboratories of Frank Ruddle from Yale, Frank Constantini and Elizabeth Lacy from Oxford, and Ralph Brinster and Richard Palmiter from University of Pennsylvania and University of Washington injected purified DNA into a single-cell mouse embryo and showed transmission of the genetic material to subsequent generations. During the early eighties the technology used to generate genetically modified mice was improved into a tractable and reproducible method.Transformation of animal and plant cells was also investigated with the first transgenic mouse being created by injecting a gene for a rat growth hormone into a mouse embryo in 1982

41	)Green biotechnology

Green biotechnology makes use of modern technologies such as recombinant-DNA technology to explore the potential of plants to build a sustainable world. In laboratories all over the world such modern technologies are being uses to unravel the basic mechanisms of the behaviour of plants, such as its growth, or its reactions to biotic and abiotic stresses. Reductionistic approaches have been replaced by looking at the plant as a whole. High-throughput technologies and bio-informatics are used to create understanding of the complex interactions between numerous genes, proteins and metabolites. The knowledge generated, can be used in different ways and in different types of applications. It can lead to changes in crop management, but also lead to new directions in plant breeding, and also to the development of genetically engineered crops.

In a world of global warming green biotechnology can contribute in different ways to decrease carbondioxide emissions. I will shortly discuss two approaches:

- Create significant rises in the per hectare yield of crops to prevent further deforestation.

- Improve the potential of plants as a source for bio-energy, such as bio-ethanol or other types of fuel.

Plants for bio-energy

Plants are already used quite a bit for the production of different biofuels, such as biodiesel or bio-ethanol. Traditionally plants have been developed for providing healthy foods, and that is why corn nowadays have very big stalks, and wheat and rice are not very tall. Crops have not been seriously selected as a source of bio-energy. That means that there is still a lot of breeding potential to develop crops that have far better characteristics for bio-energy. One example that can be given is wood. Wood – or to be more precise: the cellulose and hemicellulose in wood – can be converted to bio-ethanol or other types of biofuel, but the conversion today is still inefficiënt. One technological strategy which also involves modern biotechnology is to develop better enzymes to do the conversion. A second strategy is to alter the wood properties to make it more suitable for the conversion. Poplar trees have been made that have less lignin. This is a sort of glue that is responsible for the enzymes not being able to do their work efficiently. Wood produced in a greenhouse has been shown to produce up till 50% more bio-ethanol than conventional wood. Also traditional breeding can help to improve performance, for instance by developing varieties that are better suited for growing in socalled ‘short rotation’. In short rotation you don’t want one dominant stem, but many equally good growing branches. Short rotation is a modern way of growing woody biomass and yields can go up to 30 tons of dry mass per hectare per year, depending on the circumstances.

 

The way green biotechnology can contribute to reducing carbondioxide emissions may seem somewhat indirect, but it is real and meaningful. Besides working on yield and the suitability for bio-energy there are other approaches, such as developing crops that can still grow and capture carbondioxide under harsh conditions such as drought, salinity or cold. At least one thing is certain: to fight climate change and become more sustainable we literally have to become greener. We have to grow as much plants as possible.

Green biotechnology is biotechnology applied to agricultural processes. An example would be the selection and domestication of plants viamicropropagation. Another example is the designing of transgenic plants to grow under specific environments in the presence (or absence) of chemicals. One hope is that green biotechnology might produce more environmentally friendly solutions than traditional industrial agriculture. An example of this is the engineering of a plant to express a pesticide, thereby ending the need of external application of pesticides. An example of this would be Bt corn. 

47)The methods of experimental Haploid technology The most commonly used method to create haploid plants in a method of in vitro androgenesis - formation of haploid plants from anther cells cporogennoy usually in the phase of vacuolated microspores. However, this process is depends on several interrelated factors, each of which has an influence on the morphogenetic processes when cultured anthers isolated microspores in vitro. For some crops showed that embryogenesis depends on genetic, physiological reasons bud stage of development, and microspores, and environmental factors such as composition of the nutrient medium (mineral and hormonal composition), and culturing conditions (liquid, solid nutrient medium and light temperature regimes) [2,3,9]. The results showed that still embryogenesis in anther culture in vitro occurs spontaneously and has a low frequency output of haploid plants (1 - 4%), and the proposed technology is difficult and poorly reproducible studied at each stage androgenesis [1, 5, 7, 8]. Therefore, the development and improvement of existing methodological approaches, it is necessary to carry out, given the genotypic characteristics of the samples.

The development of these structures occur in two ways: 1) formation of embryos, 2) the formation of elongated cells and their subsequent destruction. Visually it was observed that the formation of embryos occurred only if the structure to fall medium after anther rupture. If the structures remained within the anther, it was observed the formation of elongated cells, which was similar to the process of pollen germination in vivo. One can assume that the lowest frequency of embryogenesis in the culture isolated anther associated with low cell yield structures medium.