What is the fundamental problem with genetic plant modification (GE/GM)? The answer is relatively simple. The DNA of cotton, corn, soy, canola and other plants can all be made resistant to specific herbicide/s, or otherwise changed in an attempt to harvest from them fuel oils, drugs etc.
Many plants are already resistant to certain herbicides, e.g. many grasses are unaffected by broadleaf herbicides (BH), so BH-resistant cereals are 'oversprayed' with BH on to the crop without killing them. The extent to which conventional, non-GM, non-organic farmers rely on these is something many organic growers may not realise.
Indeed, some of our most vocal opponents of GM are actually these same 'conventional' non-organic farmers (eg anti-GM spokesperson Julie Newman from WA). But many farmers do not realise the ultimate threat emanting from GM: loss of food security, and possible financial security, arising from potential contamination/cross-pollination from adjacent GM crops.
Giant GM monopolies hold individual farmers responsible for any contamination arising, setting the scene for drawn-out 'David and Goliath'-style legal conflicts (such as the infamous case Monsanto vs. Percy Schmeiser (photo). Whether it be an environmental factor (drought, wet, heat, cold, soil type) or a disease (fungal, viral, bacterial etc) or a chemical (ie herbicide), there will always be an individual member of a species (be it human, animal or plant) which has, or develops, a resistance to something in order to enhance its survival chances. It may be only 1:100 to begin with.
The reason for this is a function of epigenetics. Epigenetics means a change in gene function. In genetic modification this adaption is artificially engineered, i,e it is not a natural function which would lead to selection for plant beeding. Epigenetics means that an individual organism adjusts itself in that environment, due to non-genetic factors that influence the behaviour of cells traits and functions. At any one time, maybe only a small number of genes are actually "switched on" as a response to external factors. Most genes are simply dormant, but will switch on, if and when required to respond to the environment.
A good example is when a species shrinks in size as a response to shrinking resources. It is known that horses did this in North America about 55 million years ago in response to the altered environment of high CO2 and subsequent soaring temperatures. The environmental causation may vary, but the result is similar, and other examples have been found. In approx. 8,000 years of plant breeding, selections have been made which have led to specific crosses (or hybrids) which can also be naturally occurring.
However, in GM there is a 'forced mutation', whereby a gene is inserted by a 'shotgun' method into plant DNA. Sometimes this gene comes from a virus, bacteria or other non-plant species. The method creates a 'forced entry' and it is energetically unstable. Epigenetics, on the other hand is 'crosstalk' between the genes and the environment.
A genome is a 'full complement of genetic material within an organism'; it can change within one generation (called a fluid genome). This assists a species to develop natural resistance to new diseases, insects, weed competitors, etc. Fusarium wilt is becoming more endemic in crops sprayed with, and resistant to, glyphosate. As these GM glyphosate-resistant plants are just one genotype, they may not be able to develop a resistance to fusarium. They are really only one individual multiplied, and GM scenarios can only further reduce the biodiversity of crop seed stocks.
A film titled "Outfoxed" explores the 'missing link' between production and environmental understanding, ie reductionist science and technological power dominating ecological understanding and human wisdom. The result of business interest steering technology is GM, the stated aims of which are reduction of chemical use and increasing crop yields, neither of which have materialised.
The real agenda is business promotion. GE/GM however is an extraordinarily experimental procedure. Unravelling DNA cannot explain how it works, so shooting or injecting foreign DNA at random into other DNA carries a risk. If you don't know how it works, how can you be assured of a specific outcome? As life is biologically active, the outcome cannot be guaranteed. GM is altered DNA, but it is far from clear what exactly has been altered.
The above article is partly sourced from notes taken during a talk by Dr Maarten Stapper, ex-CSIRO, BSc, AgEng,PhD, Adelaide, Tuesday 18th September 2007
Deb Guildner
You might also want to visit http://www.organicconsumers.org/monlink.cfm for futher information.
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