Protected: Australian children worried about terrorism: study
Enter your password to view comments June 12, 2007
Can’t have it both ways
A 2005 study by Dr Donald Davis, research associate at the Biochemical Institute at Texas University, found concrete evidence of genetic trade-offs between yield and mineral concentration in broccoli (reduced calcium and magnesium); in wheat (iron, zinc, copper, selenium, phosphorus, and sulfur); and in 32 crop plant varieties.
Similarly, a study by Dr Danny Asami in the Journal of Agricultural and Food Chemistry found that successful strategies to increase production (such as selective breeding and nitrogen fertilisers) resulted in decreased nutrient density and less flavoursome produce, because accelerated growth promotes an excess of sappy tissue in plant cell walls.
And according to US agricultural scientist Dr Charles Benbrook, this excess of fast-growth sappy tissue means lower resistance to pests and disease. Dr Benbrook’s studies found that GM crops that have initial higher yields have, for this reasons, needed greater herbicide and pesticide application in the long term.
We’d all like to see greater yields and higher nutrition, but these studies might suggest that when you manipulate one trait in a genetic system as complex as a plant, something’s got to give.
Add comment June 8, 2007
Rethinking Objectivity
Brent Cunningham’s article in the Columbian Journalism Review.
Add comment May 17, 2007
