Biomass degradation after harvest of genetically modified products compared to conventional counterparts

Abstract

Conventional breeding and modern biotechnology tools have been successfully combined over the years to generate GM crops. Single events have been crossed to generate stacked products and these combinations have proven to be an effective way to combine different gene products and associated characteristics which are agronomically relevant and result in yield increase. Regulatory agencies around the world still require risk assessment data for these products while no evidence-based additional biosafety concerns have emerged in over 20 years of global use. As part of the environmental risk assessment to evaluate the biosafety of GMOs, the Brazilian regulatory agency requests biomass degradation analyses of GM plants compared to their conventional counterparts. Here we present results on the evaluation of biomass degradation of GM and non-GM crops for soybean, maize and cotton, including single events and stacked products. Field trials were performed in representative cultivated areas in Brazil to generate biomass samples after harvest. Stalks, senescent leaves and stems after harvest were considered the biomass assessed. Collected samples were used in degradation studies conducted in a greenhouse setting from 2012 to 2019. For each product, data was subjected to analysis of variance and pairwise differences between GM and conventional counterparts were assessed with a 5% significance level. Our results show that single events and stacked products of soybean, maize and cotton presented no significant differences from their conventional counterparts for biomass degradation. This adds to the existing weight of evidence that indicates that single and stacked GM crops follow the same pattern of biomass degradation compared to conventional counterparts.