15-Year Study Finds Bt Rice Has Minimal Impact on Soil Microbes

A 15-year study conducted by researchers from China National Rice Research Institute found that Bt rice had minimal effects on the bacteria living in the soil. Instead, factors such as the time of sampling, crop growth stage, and soil depth had a greater influence on soil bacterial communities. Researchers combined long-term field monitoring with interpretable machine learning to assess how Bt rice cultivation affects soil microbiomes.

The analysis found no significant differences in bacterial diversity between soils planted with Bt and non-Bt rice. Instead, changes over time and differences in soil depth were the strongest factors shaping microbial communities. Machine learning identified several bacterial groups that consistently helped distinguish Bt from non-Bt soils, although their abundance differences were small and their ecological roles remain unclear.

The researchers concluded that Bt rice has a relatively minor influence on overall soil bacterial community structure. They highlighted the value of long-term monitoring and transparent machine-learning approaches for evaluating the environmental effects of genetically modified (GM) crops and recommended further research to determine whether the identified microbial changes have meaningful ecological functions.

For more information, read the study from Environment International.