What are the genetic eng techniques used for plants?

Question

teaching A level bio kids get lost in all the plant techiques used

Answer 1

The intentional creation of transgenic plants by laboratory based recombinant DNA methods is more recent (from the mid-70s on) and has been a controversial development in the field of biotechnology opposed vigorously by many NGOs, and several governments, particularly within the European Community. These transgenic recombinant plants (= biotech crops, modern transgenics) are transforming agriculture in those regions that have allowed farmers to adopt them, and the area sown to these crops has continued to grow globally in every years since their first introduction in 1996.[citation needed]

Transgenic recombinant plants are generated in a laboratory by adding one or more genes to a plant's genome,and the techniques frequently called transformation. Transformation is usually achieved using gold particle bombardment or through the process of Horizontal gene transfer using a soil bacterium, Agrobacterium tumefaciens, carrying an engineered plasmid vector, or carrier of selected extra genes.

Transgenic recombinant plants are identified as a class of genetically modified organism(GMO); usually only transgenic plants created by direct DNA manipulation are given much attention in public discussions.

Transgenic plants have been deliberately developed for a variety of reasons: longer shelf life, disease resistance, herbicide resistance, pest resistance, non-biological stress resistances, such as to drought or nitrogen starvation, and nutritional improvement (see Golden rice). The first modern recombinant crop approved for sale in the US, in 1994, was the FlavrSavr tomato, which was intended to have a longer shelf life. The first conventional transgenic cereal created by scientific breeders was actually a hybrid between wheat and rye in 1876 (Wilson, 1876). The first transgenic cereal may have been wheat, which itself is a natural transgenic plant derived from at least three different parenteral species.

Genetically modified organisms where prior to the coming of the commercially viable crops as the FlavrSavr tomato, only strictly grown indoors (in laboratories). However, after the introduction of the Flavr Savr tomato, certain GMO-crops as GMO-soy and GMO-corn where in the USA being grown outdoors on large scales.

Commercial factors, especially high regulatory and research costs, have so far restricted modern transgenic crop varieties to major traded commodity crops, but recently R&D projects to enhance crops that are locally important in developing counties are being pursued, such as insect protected cow-pea for Africa. [6], and insect protected Brinjal eggplant for India [7].

Transgenic plants have been used for bioremediation of contaminated soils. Mercury, selenium and organic pollutants such as polychlorinated biphenyls (PCBs) have been removed from soils by transgenic plants containing genes for bacterial enzymes[

Answer 2

The main technique for genetic engineering in plants today is Agrobacterium mediated transformation.  Agrobacterium is a unique prokaryote in that it carries a plasmid that is specially designed to introduce DNA into the nucleii of plants.  Scientists have modified this plasmid to remove its pathogenic characteristics yet retain the ability to inject DNA into plants.  Scientists typically will insert the DNA (typically a modified gene) into the plasmid then expose plants to suspensions of the Agrobacterium carrying this plasmid.  It works quite well with practice.  Seed produced by the plant can then be tested for the presence of the new gene (called a transgene).  Typically the new gene is linked to a gene confering resistance to an antibiotic.  Hence, plantlets that are resistant to the antibiotic can be assumed to be carrying the transgene.  Frequencies of seed transformation can be a few percent.  This may sound low but for a species making a lot of seed (like Arabidopsis) it is a quite good frequency.  You can also see the value of the antibiotic screen.