Field trial of insect-resistant and herbicide-tolerant genetically modified cotton (Gossypium hirsutum L.) for environmental risk assessment in Japan

Abstract

Japan imports cottonseed mainly from Australia and the USA where more than 96% of all cotton varieties grown are genetically modified (GM). GM crops undergo an environmental risk assessment (ERA) under the Law Concerning the Conservation and Sustainable Use of Biological Diversity before import into Japan. Potential adverse effects on biodiversity are comprehensively assessed based on competitiveness, production of harmful substances and outcrossing ability. Even though imported cottonseed is intended for food and feed uses and not for cultivation, the potential risks from seed spillage during transport must be evaluated. In most cases, the ERA requires data collected from in-country field trials to demonstrate how the GM crop behaves in Japan's environment. Confined field trials in Japan were conducted for the ERA of Lepidoptera-resistant and glufosinate-tolerant GM cotton (Gossypium hirsutum L.) lines GHB119 and T304-40. These lines were compared with conventional varieties for growth habit, morphological characteristics, seed dormancy, and allelopathic activity associated with competitiveness and production of harmful substances. Outcrossing ability was not a concern due to the absence of sexually compatible wild relatives in Japan. Although slight statistical differences were observed between the GM line and its conventional comparator for some morphological characteristics, transgenes or transformation were not considered to be responsible for these differences. The trial demonstrated that competitiveness and production of harmful substances by these GM cotton lines were equivalent to conventional cotton varieties that have a long history of safe use, and no potential adverse effects to biosafety in Japan were observed.

Environmental risk assessment of transgenic miraculin-accumulating tomato in a confined field trial in Japan

“…However, in most of these approvals, the procedures and details of the experimental results of the confined field trials conducted to assess environmental risks were not disclosed. In recent years, some of these product experiments have been published in scientific papers, such as those concerning soybean (Matsushita et al 2020), oilseed rape (Asanuma et al 2011), and cotton (Asanuma et al 2017), but the information available to the public is limited. Therefore, we hope that the information in this paper will contribute to regulatory science efforts for other crop species, including GM tomato.…”

“…While fresh soil is free of contaminants such as plant roots, it has smaller pores, making it more difficult for roots of subsequent plants to physically grow compared with plants in pre-cultivated soil. Asanuma et al (2017) also pointed out that the roots of test plants are susceptible to external factors and thus, they eliminated soil pores by using a 5-mm mesh screen to remove plant residues and make the soil particle size uniform. In the present study, we removed the major root residues visually.…”

“…In most of these studies, the details of the procedures and the results of the experiments conducted for environmental risk assessment in confined field trials are usually not disclosed. Although a few reports have described the details of confined field trials in soybean (Matsushita et al 2020), cotton (Asanuma et al 2017) and oilseed rape (Asanuma et al 2011), they are atypical. In addition, to date, there is no regulatory approval for the cultivation of GM tomato plants in Japan.…”