Growth Performance and Fitness Analysis of Backcross Progenies of Herbicide-Tolerant Transgenic Soybean and Wild Soybean.

Gene escape from genetically modified (GM) soybean may have ecological and genetic effects on wild populations. To assess the potential risks associated with backcrossing GM soybean with wild soybean, seed dormancy, inheritance of herbicide resistance, and plant growth in F1, BC1F1, and BC2F1 lines were comprehensively analyzed. The results showed that, compared with those of wild soybean, the seeds of BC1F1 and BC2F1 also exhibited dormancy, albeit at significantly lower levels. BC1F1 and BC2F1 showed reduced biomass (by 6-7%; p > 0.05) and inferior reproductive performance, with the numbers of pods, seeds, and filled seeds per plant decreasing by 27.02-29.57% (p < 0.05). However, glyphosate spraying tests demonstrated that 46.3% of the BC1F1 plants and 30.6% of the BC2F1 plants were resistant to glyphosate. Moreover, exogenous protein assay results confirmed that the exogenous gene was stably inherited in these plants, which confers a significant growth advantage under selection pressure. These findings provide new scientific evidence for assessing the ecological risks associated with the environmental release of GM soybean.