文档介绍：Methods of producing transgenic plants
Part II
Plant Biotechnology
Traditional crossbreeding
binant
DNA techniques
ngreso/ponencias/5
The results of traditional Agbiotech are not that bad, but they are time-consuming
teosinte
cob
corn
John Doebley photo
Wild tomato
(Lycopersicon pimpinellifolium )
D= 1 cm
ign/ Samples/plant-
Hybrid plants
(heterosis)
Agricultural Biotechnology
Crossbreeding
binant DNA
Species
Related
Related/unrelated
Efficiency
Susceptibility to external gene influences
Genes shuffled in one exepriment
10s of 1000s
1 – few
Random insertion
+
+
Insecti and herbicides
Fertilizers
Pollution/run off
Potential toxins/risk
+
+
ngreso/ponencias/5
Introducing genes into plants
infecting plant cells with plasmids
as vectors carrying the desired gene;
2) shooting microscopic pellets
containing the gene directly into the cell.
ic engineering of plants with Agrobacterium tumefaciens
A. tumefaciens: used extensively for ic engineering of plants.
Contains T-DNA (bacterial plasmid)
Genes colud be integrated into the plant chromosomes when the T-DNA is transferred.
Tumor induced by
A. tumefaciens
gall is not a tiny thing
Biology of A. tumefaciens
/teknik/ djup/
Well known to induce crown gall tumor
lives around
root surfaces (in rhizosphere)
where it using nutrients
that leak from the root tissues
infects only through wound sites
and actively chemotactic to them
Plant wound produces
acetosyringone
Bacterial T-plasmid produces
receptors for acetosyringone