The larvae of click beetles, called wireworms, can cause major crop losses in many different crops. For their control in potato cultivation, a soil granule based on the insect pathogenic fungus (Metarhizium brunneum) was developed. A major challenge hereby are the soil temperatures at the time potatoes are planted. Because they are below the temperature optimum of the fungus, its growth and sporulation are inhibited. Since these factors are crucial for its effect, we investigated whether the growth, germination and virulence of a fungus can the influenced by its production conditions. We determined that an insect pathogenic fungus produced at higher temperatures subsequently grew better and germinated faster. However, the virulence of the fungus was independent of its production temperature. This finding demonstrates that the production process can already influence the quality of a biological plant protection agent.

Seib, T., Fischer, K., Sturm, A. M., & Stephan, D. (2023). Investigation on the Influence of Production and Incubation Temperature on the Growth, Virulence, Germination, and Conidial Size of Metarhizium brunneum for Granule Development. Journal of Fungi, 9(6), 668. https://doi.org/10.3390/jof9060668