Free access article

Issue Environ. Biosafety Res. Volume 5, Number 3, July-September 2006 Page(s) 169 - 173 DOI 10.1051/ebr:2007003 Published online 28 March 2007

Environ. Biosafety Res. 5 (2006) 169-173
DOI: 10.1051/ebr:2007003

Gene flow from GM glyphosate-tolerant to conventional soybeans under field conditions in Japan

Yasuyuki Yoshimura, Kazuhito Matsuo and Koji Yasuda

National Institute for Agro-Environmental Sciences, Tsukuba, Ibaraki 305-8604, Japan

(Received August 16, 2006; accepted January 6, 2007; published online 17 April 2007)

Abstract - Natural out-crossing rates were evaluated for conventional soybeans (Glycine max (L.) Merr.) cultivated adjacent to genetically modified (GM) glyphosate-tolerant soybeans under field conditions during a four-year period in Japan. A total of 107 846 progeny of 2772 plants harvested from conventional varieties were screened for glyphosate herbicide tolerance. The highest out-crossing rates, 0.19% in 2001 and 0.16% in 2002, were observed in adjacent rows 0.7 m from the pollen source. The highest rate in 2004 was 0.052%, which was observed at 2.1 m. No out-crossing was observed in the rows 10.5 m from the pollen source over the four-year period. The farthest distances between receptor and pollen source at which out-crossing was observed were 7 m in 2001, 2.8 m in 2002, and 3.5 m in 2004. The greatest airborne pollen density during the flowering period, determined by Durham pollen samplers located between the rows of each variety, was 0.368 grains.cm^-2.day^-1, with the average value at 0.18 grains.cm^-2.day^-1, indicating that the possibility of out-crossing by wind is minimal. Thrips species and predatory Hemiptera visited the soybean flowers more frequently during the four-year period than any other common pollinators, such as bees.

Key words: gene flow / soybean / glyphosate-tolerant / out-crossing / pollen

Corresponding author: yyoshi@niaes.affrc.go.jp

© ISBR, EDP Sciences 2007

What is OpenURL?