このウェブサイトではJavaScriptおよびスタイルシートを使用しております。正常に表示させるためにはJavaScriptを有効にしてください。ご覧いただいているのは国立国会図書館が保存した過去のページです。このページに掲載されている情報は過去のものであり、最新のものとは異なる場合がありますのでご注意下さい。
NIAES > Priority Research Areas (2006-2008) > Understanding the Ecological Impact of Genetically Modified Organisms
The planted acreage of genetically modified crops is increasing every year, crossing the 100 million hectare mark in 2006. This is more than 2.6 times as large as Japan's total land area. While in Japan no genetically modified crops have been cultivated commercially so far, we are conducting research in three major areas based on the objective of understanding the possible impact of such crops on agricultural ecosystems: (1) gene transfer from genetically modified crops to wild relatives; (2) gene transfer from genetically modified crops to non-genetically modified crops of the same species; and (3) monitoring of genetically modified crops. These studies will provide data that are needed for the development of technologies to ensure the safe use of genetically modified crops, as well as for the establishment of the rule-making processes for the coexistence of genetically modified crop growers and non-genetically modified crop growers.
Fig. 1 Experimental station for natural hybridization test of genetically modified soybean and Glycine soja
Concerns have been raised about possible hybridization of genetically modified soybean (Glycine max), if imported into Japan, with its wild relative Glycine soja that grows naturally in Japan and other East Asian countries. Accordingly, a genetically modified herbicide-resistant soybean that has been allowed for cultivation in Japan is grown at an experimental station, and Glycine soja is grown at 5 different distances from the soybean plants. The degree of possible hybridization will be analyzed with respect to the differences in the distance (Fig. 1).
Fig. 2 When the pollen of a yellow-grain corn plant drifts and comes into contact with the pistil of a white-grain corn plant, the white-corn grains turn yellow (the so-called xenia phenomenon).
If genetically modified corns or rice are grown, their pollen will drift and may hybridize with non-genetically modified crops of the same species that are grown in nearby uplands. Taking advantage of a phenomenon called “xenia” (Fig. 2) and the technique of pollen dyeing (Fig. 3), we will investigate how far pollens drift away from the source and, as a consequence, the extent of hybridization. Models will be developed to predict the hybridization ratio by collecting data on the weather conditions at the time of flowering (wind direction, wind velocity, etc.), and the pollen densities at pollen source and at farmlands downwind. Furthermore, techniques will be developed to contain hybridization by the use of windshield nets and other obstacles to reduce wind velocity.
Fig. 3 Dyeing the pollen with iodine-potassium iodide solution distinguishes nonglutinous rice from glutinous rice.
In a number of international ports in our country, the growth of genetically modified oilseed rape has been reported, apparently deriving from escaped seeds of imported rapeseed (Brassica napus L.) (Fig. 4). Accordingly, a monitoring station has been installed in the vicinity of Port of Kashima to carry out fixed-point observation of the emergence and seasonal prevalence of Brassica napus L. This study will clarify whether or not such rapeseeds are likely to advance into nearby plant communities and expand their geographical distribution.
Fig. 4 Brassica napus L. growing along a main road near the Port of Kashima. Holotype of Noctuidae
Research Project for Ecological Impact Assessment of Genetically Modified Organisms
National Institute for Agro-Environmental Sciences
3-1-3 Kannondai, Tsukuba, Ibaraki 305-8604, Japan
Tel: +81-29-838-8271