@JS19
...I must admit that the species creep is anecdotal, the crop is Roundup Ready (tm) cotton and the weed species is Bindweed, which looks like morning glory. I heard this from farmers and from the agricultural extension guy, neither has any reason to lie about it.
The discussion led me to a little further research:
http://pubs.acs.org/doi/abs/10.1021/bk-1996-0645.ch021
"Resistance to herbicides, pathogens and insects may occur in wild plant species through mutation and introgression with other species. The movement of genes among plants provides weeds with the opportunity to express new properties and modify their invading potential. Examples of gene flow within and between weed populations, between weed species, and between crops and weeds are reviewed. Special attention is given to herbicide resistance genes and gene flow between genetically engineered crops, that display new highly adaptive genes, and weeds."
http://agribiotech.info/details/Stewart-GeneFlow%20Mar%208%20-%2003.pdf (warning PDF)
"Horizontal gene flow is the movement of genes between disparate, unrelated species, such as between plants and microbes. [...] there is good evidence that genes have moved between species in evolutionary time. One well-characterized case is the movement of genes from the soil bacterium Agrobacterium tumefaciens to plants"
By whatever mechanism, the introduction of herbicide resistance to weed species IS taking place to the extent that, in the words of the aggie agent, "It Looks we won't have Roundup any more."
The short term danger to farmers, however is economic, for example, pollin from GMO soybeans is carried to non GMO crops. Two things happen to the farmer:
1. The crop may not be exported to countries where GMOs are prohibited.
2. If the farmer saves and plants his own seeds, he is sued for patent infringement by Monsanto.
Biting the hand that feeds IT
