The total global area of GM crops increased 12 percent in 2007 compared to the previous year, bringing total GM land area up to 114.3million hectares, said the Worldwatch Institute in its latest estimates published in its Vital Signs Update.
This means it accounts for nine percent of global primary crop production and four cash crops account for virtually all GM production: soybean (51 percent); corn (31 percent); cotton (13 percent); and canola (5 percent).
In a climate of rising food insecurity where food manufacturers face volatile commodity prices and supply issues, GM crops have been promoted as a way of helping to ease a food crisis.
Companies leading the GM march include Monsanto. The report said its GM crop traits are found in more than 85 percent of global GM crop hectares and the company controls 23 percent of the global proprietary seed market, said the report.
However, controversy over the benefits of genetic modification continues, including questions about the technology's ability to deliver on promises of enhanced yields and nutrition.
The report said: “Claims of potential benefits from GM crops include increased yields and nutritional value, although to date no commercially available crops have been modified for these purposes.
“Some studies have shown that GM crops reduce yield performance, including a 5- to 10-percent yield drag in GM soybeans.
“And although nutrition-related traits have been promised over the last decade, they are still at least five years away from market.”
It also highlighted several concerns surrounding GM crops, including the transfer of food allergens across crop species, the unintentional spread and gene flow of GM crops, contamination of organic and other non-GM crops, the development of weed and pest resistance, and toxicity to animals that may feed on or near the crops.
Alice McKeown, a researcher for the Worldwatch Institute and author of the report, said: "GM crops are definitely not a silver bullet. They sound good on paper, but we have yet to see glowing results."
"There are still many unanswered questions about GM crops. But the good news is that we have solutions to food security and other problems available today that we know work and are safe for humans and the environment, including organic farming."
The United States produced half of all GM land area in 2007 as biotech crops grew on 57.7m hectares, which was an increase of six percent on the previous year.
The second and third largest countries for GM crop area are Argentina and Brazil.
The report said that two GM crop traits continue to dominate worldwide herbicide tolerance (63 percent) and insect resistance (18 percent), with a combination of the two traits accounting for the rest.
The Worldwatch Institute says it is an independent research organization that offers accessible, fact-based analysis of critical global issues.