제초제 저항성 GM 들잔디(Zoysia japonica Steud.)의 화분에 의한 유전자 이동성 평가

Abstract

This study was performed to estimate the possibility of pollen-mediated gene flow of a genetically modified (GM) herbicide-tolerant zoysiagrass, which is required for commercial cultivation of GM crops. Chapter 1, environmental factors affecting on anthesis and pollen viability have been checked. The pollens were released predominantly at 8:00~10:00 in day cycle, their viabilities were greatest as well. The pollen viability or longevity was best at the temperature and humidity of 15~20oC and 80~99%, respectively, which were varied depending on the atmospheric change. Under sunny condition, the pollen was germinable only up to about 120 min after anthesis, but under cloudy condition, up to 450 min after anthesis, extending at least above 2-times compared to that under sunny condition. In addition, no significant difference was found between GM and non-GM zoysiagrass in their pollen viability or longevity. Chapter 2, the pollen-mediated gene flow from the GM zoysiagrass to non-GM zoysiagrass species by measuring crossing-over rate of herbicide-resistant bar gene using three experimental models which include unidirectional population combination (UPC), field-to-field, and radial model have been checked from 2007 to 2011. In comparative close distance of below 5m, the gene flow rate was measured around 3~5.7% in the UPC and field-to-field models. The distance from the GM source was longer, the gene flow rate lower. The gene flow was found at very low frequency of 0.25% in 38m, but not found outward longer distance than it. In the radial model, the gene flow rate was 3.7% in the radius of 3m, and that was found to be high toward the directions of northeast, southwest, and west. The local meteorological data supported that the gene flow rate varying according to the position of pollen recipient (non-GM zoysiagrass) might be influenced by wind direction and speed during flowering season.