Light spectrum is a crucial environmental factor influencing plant growth and secondary metabolite production in controlled-environment agriculture. This study investigated the combined effects of light spectral composition on growth performance and andrographolide accumulation in Andrographis paniculata (Burm.f.) cultivated in a plant factory system. Two Thai cultivars, RBR and TTT, were grown under white light and various red–green–blue (R:G:B) LED ratios during the vegetative and flowering stages. Plant morphological traits, biomass accumulation, and andrographolide derivatives (AP1, AP4, AP6, and total AP) were quantified. Growth and biomass production were significantly enhanced under white light and red-enriched spectra, particularly during the vegetative stage, whereas stem elongation exhibited reduced sensitivity to light spectral quality during the flowering stage. In contrast, andrographolide accumulation showed a strong cultivar-dependent response to light spectrum. The TTT cultivar showed pronounced increases in AP1, AP4, AP6, and total AP under blue-enriched spectra, with the 60B:10G:30R treatment producing the highest total diterpenoid content in both cultivars, while the RBR cultivar displayed limited responsiveness to spectral variation. These results demonstrate light spectrum affecting both biomass production and phytochemical accumulation. Optimization of light spectral composition combined with appropriate cultivar selection offers an effective strategy for enhancing pharmaceutical-grade andrographolide production in plant factory systems.

Holy basil (Ocimum tenuiflorum L.) is an extensively utilized herb, encompassing numerous bioactive compounds that hold significant interest in the food and pharmaceutical industries. High-throughput phenotyping is a rapid and non-invasive technique, providing diverse phenotypic trait observation and measurement. However, basic knowledge regarding the diversity among varieties beneficial for large-scale production in terms of yield and secondary metabolites under a controlled greenhouse environment is limited. Hence, we assessed and classified 12 Thai accessions and two commercial cultivars by evaluating growth, yield, and secondary metabolites at each harvesting time using an advanced NSTDA-Plant Phenomics platform. Notably, accessions OC130, OC141, OC072, and OC059 demonstrated stable metabolite production and antioxidant activity, highlighting their potential as superior accessions for further cultivation and utilization. These findings underscore the potential for tailored cultivation practices to manipulate secondary metabolite synthesis, thereby enhancing the medicinal properties and market value of Thai holy basil. The implications of this study extend to farmers, providing valuable insights into the phenotypic variation and practical avenues under consistent environmental conditions. Breeders can observe genetic diversity to improve basil varieties with desirable traits for specific environmental niches. Moreover, modern agricultural practices can benefit from understanding the impact of controlled environments on secondary metabolite synthesis.