ABSTRACT

Transgene escape into natural ecosystems through seed spraying or transgene introgression may potentially cause environmental biosafety problems. In this study, we assessed the environmental risk of insect-resistant transgenic rice entering farmland margins or natural ecosystems adjacent to farmland. Transgenic Cry1C* rice (T1C-19) was used to study the effects of exogenous Cry1C* expression on vegetative and reproductive growth indices under different growing conditions using the following four combined treatments of land use and weeds: farmland and uncultivated land without weeds (F–NW and U–NW, respectively), and farmland and uncultivated land with weeds (F–W and U–W, respectively). The expression of Cry1C* protein under the U–NW, F–W, and U–W conditions was significantly lower than under the control condition, F–NW. Tiller number, biomass, filled grain number, filled grain weight, and other vegetative and reproductive indices were significantly lower in the rice line TIC-19 than in MH63 under F–NW and U–NW conditions, indicating a significant fitness cost. However, under F–W and U–W conditions, vegetative growth indices such as plant height, tiller number, and biomass, as well as reproductive growth indices such as filled grain number per plant, filled grain weight per plant, and seed setting rate in TIC-19 were similar to those in MH63, indicating a long-term coexistence. These results indicate a lower ecological risk of T1C-19 compared to MH63 under F–NW and U–NW, although their long-term coexistence may lead to potential ecological risks under F–W and U–W.

摘要

转基因通过种子喷洒或转基因渗入逃逸到自然生态系统中可能会导致环境生物安全问题。在这项研究中，我们评估了抗虫转基因水稻进入农田边缘或农田附近自然生态系统的环境风险。转基因Cry1C*水稻 (T1C-19) 用于研究外源Cry1C的影响* 使用以下四种土地利用和杂草组合处理在不同生长条件下的营养和生殖生长指数的表达：农田和无杂草荒地（分别为F-NW和U-NW），以及有杂草的农田和荒地（分别为 F-W 和 U-W）。Cry1C* 蛋白在 U-NW、F-W 和 U-W 条件下的表达显着低于对照条件 F-NW。在 F-NW 和 U-NW 条件下，水稻品系 TIC-19 的分蘖数、生物量、饱满粒数、饱满粒重和其他营养和繁殖指标显着低于 MH63，表明适应性成本显着。然而，在 F-W 和 U-W 条件下，植物高度、分蘖数和生物量等营养生长指数，TIC-19的单株饱满粒数、单株饱满粒重、结实率等生殖生长指标与MH63相似，表明长期共存。这些结果表明，与 MH63 相比，F-NW 和 U-NW 下 T1C-19 的生态风险较低，尽管它们的长期共存可能导致 F-W 和 U-W 下的潜在生态风险。