Next-gen organic tomato cultivation system with peppermint companion planting

Abstract

Volatile compounds emitted by herbivore-damaged plants enhance the defense responses of neighboring, undamaged plants. However, the practical application of such damaged plants in agriculture has yet to be realized due to various constraints. To address this challenge, recent studies have demonstrated that komatsuna and soybean plants grown near peppermint or candy mint, which continuously and abundantly release volatile organic compounds, exhibit increased expression of defense-related genes, such as pathogenesis-related 1(PR1), in their leaves, thereby strengthening their resistance to pests and diseases. However, the potential effects of this approach on tomato, a globally significant crop in the Solanaceae family, remain unexplored. In this study, young tomato plants were cultivated for seven days in a growth chamber, positioned 10 cm from peppermint. The results revealed an upregulation of PR1 expression in tomato leaves, indicating that peppermint effectively enhances tomato defense responses. Additionally, a field experiment was conducted in which tomato plants were placed at varying distances from peppermint and grown for three weeks. The findings showed that tomatoes positioned 20 cm, 50 cm, and 100 cm from peppermint experienced damage rates of 20.9%, 37.4%, and 74.3%, respectively, compared to control plants grown 200 cm away. These results suggest that peppermint may serve as an effective companion plant for pest management in tomato cultivation.