Xianming Yang, Shengyuan Zhao, Bing Liu, Yu Gao, Chaoxing Hu, Wenjing Li, Yizhong Yang, Guoping Li, Lili Wang, Xueqing Yang, Haibin Yuan, Jian Liu, Dazhong Liu, Xiujing Shen, Kris A. G. Wyckhuys, Yanhui Lu, Kongming Wu*. Bt maize can provide non-chemical pest control and enhance food safety in China. Plant Biotechnology Journal, 2022.

Summary

China is the world's second largest maize producer and consumer. In recent years, the invasive fall armyworm  Spodoptera frugiperda (J.E. Smith) has adversely affected maize productivity and compromised food security. To mitigate pest-inflicted food shortages, China's Government issued biosafety certificates for two genetically modified (GM) Bt maize hybrids, Bt- Cry1Ab DBN9936 and Bt- Cry1Ab/Cry2Aj Ruifeng125, in 2019. Here, we quantitatively assess the impact of both Bt maize hybrids on pest feeding damage, crop yield and food safety throughout China's maize belt. Without a need to resort to synthetic insecticides, Bt maize could mitigate lepidopteran pest pressure by 61.9 ~ 97.3%, avoid yield loss by 16.4 ~ 21.3% (range -11.9 ~ 99.2%) and lower mycotoxin contamination by 85.5 ~ 95.5% as compared to the prevailing non-Bt hybrids. Yield loss avoidance varied considerably between experimental sites and years, as mediated by on-site infestation pressure and pest identity. For either seed mixtures or block refuge arrangements, pest pressure was kept below established thresholds at 90% Bt maize coverage in Yunnan (where  S. frugiperda was the dominant species) and 70% Bt maize coverage in other sites dominated by  Helicoverpa armigera (Hübner) and  Ostrinia furnacalis (Guenée). Drawing on experiences from other crop/pest systems, Bt maize  in se can provide area-wide pest management and thus contribute to a progressive phase-down of chemical pesticide use. Hence, when consciously paired with agroecological and biodiversity-based measures, GM insecticidal crops can ensure food and nutrition security, contribute to the sustainable intensification of China's agriculture and reduce food systems’ environmental footprint.

Plant Biotechnology Journal, IF: 13.263

https://onlinelibrary.wiley.com/doi/10.1111/pbi.13960