Exploring the mechanisms of plant resistance to insect pests in organic and conventional hemp systems

After a nearly fifty-year hiatus, the 2018 United States Farm Bill reintroduced industrial hemp (Cannabis sativa L.) into the agricultural landscape. Although hemp has significant profit potential, there are still numerous knowledge gaps regarding best management practices. Recently, a nationwide group of hemp stakeholders and producers identified key research priorities, with many noting the dearth of information on organic production systems and insect management. Hence, the long-term goal of our research is to equip hemp producers with information that supports the development of robust and resilient organic hemp management systems, especially with regards to insect management. The specific goal of our study is to characterize plant resistance to insect pests and overall plant quality in organic versus conventional production systems. To achieve this, we conducted arthropod surveys, 16S rRNA microbial sequencing, and analyzed the phytohormones, cannabinoids, and yield of the same variety of commercially available hemp grown under organic and conventional management systems. We hypothesize that differences in beneficial insect populations, microbial taxa, and phytohormone expression will lead to distinct variation in plant quality and insect resistance between the two systems. Preliminary results show a higher abundance of both pest insects and natural enemies in the organic field relative to the conventional field. Despite this, the organic field produced greater yields across two consecutive seasons. By integrating classical entomological approaches with modern molecular techniques, our research seeks to elucidate the benefits of organic management and deliver evidence-based recommendations to hemp producers.