Title : Optimization of light intensity for growth and essential oil production of Mint (Mentha spp.) in controlled environments
Abstract:
Controlled Environment Agriculture (CEA) is a versatile technology that has the potential to reduce the environmental impact of commercial farming while simultaneously enhancing crop yield and quality. This technology is particularly promising for medicinal plants, as it offers opportunities to increase the content of valuable compounds. Innately antimicrobial, medicinally active, and valued for its desirable flavor and aroma, mint (Mentha species) is a historically and economically significant herb of the Lamiaceae family. The essential oil, which is mainly found in glandular trichomes on leaf and stem surfaces, is the most economically important component of the plant for its use in food, cosmetics, and hygienic products. Challenges presented by traditional field farming of mint, namely diseases such as verticillium wilt and increasingly unpredictable weather extremes, may be addressed in CEA. This research was conducted to optimize environmental parameters such as light intensity, photoperiod, and carbon dioxide concentration for mint growth and production of high-quality essential oil. The capital (e.g., fixtures) and energy costs associated with crop lighting are substantial crop inputs for all CEA production systems. Therefore, to optimize lighting inputs, it is necessary to determine how the quantity of photosynthetically active radiation (PAR) affects mint growth and essential oil production in CEA. A gradient design was employed in which a mint crop was grown in a heterogeneous lighting environment where individual plants were exposed to unique and well-characterized light levels. Key growth and yield parameters were collected and related to individual plants’ light levels using regression-style analyses. A subset of plants representative of the various light level acclimations were subjected to whole-plant net carbon exchange rate (NCER) measurements to assess the reliability of extrapolating short-term NCER measurements to model longer term mint growth and yield dynamics.
Audience Take Away Notes:
- I will explain the complexities of light intensity research in controlled environments, describe how the experimental design mitigates these limitations, and highlight the value of providing accurate data on plant growth responses to varying light intensities.
- Attendees may consult the data presented to make informed decisions on how their lighting will affect the growth and physiology of mint. Furthermore, the data may be used to infer the lighting costs required to reach the desired crop output.
- The presentation will outline the benefits of cultivating mint in controlled environments for producing high-quality essential oil, while addressing the remaining challenges.
- Many of the challenges associated with the traditional farming of mint are shared by other crops and medicinal plants. This presentation will show the progress being made to increase the feasibility of controlled environment agriculture systems and seeks to inspire interest within the field.
