Effect of pesticides on rhizosphere fungal diversity and community composition

Pesticide use has continued to rise worldwide as a primary strategy for crop protection, with herbicides, insecticides, fungicides, and bactericides widely applied in various forms, including seed treatments. However, this reliance on chemical inputs comes at a significant cost. Pesticides are known to harm the environment, contaminating soil and water, and disrupting ecosystems. In particular, they can damage soil microbial communities, which are essential for maintaining soil health and fertility. Beyond environmental concerns, pesticides also pose risks to human health. Farmers and agricultural workers are directly exposed during application, often facing increased risks of acute poisoning and long-term health issues. Consumers, too, may be affected through pesticide residues on food, raising concerns about chronic exposure and its potential links to health problems. These consequences highlight the urgent need to reduce pesticide dependence and promote safer, more sustainable agricultural practices. We report the findings of one year of a field study assessing the effect of seed treatment on key agronomic parameters and bacterial and fungal rhizosphere composition. The research is conducted in collaboration with farmers who intend to decrease the usage of pesticides on their farms. We compared pesticides and alternative treatments such as Thermoseed to untreated wheat plants . Cereal monitoring occurred at the time of emergence, the winter after seeding, and at harvest. Long-read PacBio Revio sequencing was utilized to characterize the diversity and composition of the fungal rhizosphere communities. The results show no significant improvement of the agronomic parameters between treated and untreated seeds regarding emergence, Septoria leaf blotch, yield, or protein quality. In addition, our sequencing data show no significant impact of seed treatment on alpha diversity . Moreover, the microbial community composition was not affected by seed treatment but was shaped primarily through soil properties. These findings support the viability of farming strategies that eliminate seed treatments without compromising yield or microbial health, reinforcing the potential for more sustainable and environmentally conscious cereal production.