Enhanced Gene Expression in the Biosynthetic Pathway of 2-Acetyl-1-pyrroline in “Hom Bon” Fragrant Native Rice in Response to Varied Light Wavelength Conditions

Abstract

The development of the Automated Agricultural Cabinet (AAC) prototype was driven by the goal of improving the aromatic qualities of locally grown rice. This compact prototype, designed with attention, employed Arduino programming to investigate genes related to the production of aromatic compounds in rice seedlings under different light conditions, including red, blue and white light. To ensure the reliability of experiments, a controlled environment was maintained at 25 °C and 75 % humidity, and rigorous testing confirmed precise light intensity measurements within the AAC. Results indicated specific light values: 9.25 ± 0.602 for red light, 11.47 ± 0.055 for blue light and 0.91 ± 0.027 µmol·m−²·s−¹ for white light. The study focused on up-regulated genes in 7-day-old ‘Hom Bon’ rice seedlings, revealing a significant increase in P5CS and 1Δ-pyrroline gene expression. These genes are crucial in the biosynthesis pathway of 2-acetyl-1-pyrroline (2-AP), with P5CS acting as a precursor and 1Δ-pyrroline as the final step. Interestingly, the study discovered that when 7-day-old ‘Hom Bon’ rice seedlings were exposed to both red and blue light, gene expression rose dramatically, contrasting when exposed to white light. This finding demonstrates that the wavelength of light exposure influences gene expression in the 2-acetyl-1-pyrroline (2-AP) biosynthetic pathway of ‘Hom Bon’ rice seedlings throughout the 7-day growth stage. This study demonstrates the feasibility of improving the smell of indigenous rice varieties by changing pre-planting light conditions, giving a promising avenue for increased commercial appeal. Furthermore, this project aims to improve the local community’s financial well-being by supporting better farming methods. HIGHLIGHTS The Automated Agricultural Cabinet (AAC) prototype has the capability to select the optimal light wavelength, inducing the up-regulation of genes associated with the 2-AP biosynthetic pathway in “Hom Bon” a fragrant native rice variety In the fragrant native rice variety “Hom Bon” the up-regulated gene in the direct 2-AP pathway, P5CS, exhibited an expression level that was twice as high as that of the housekeeping gene The red and blue wavelengths directly elevated the expression of up-regulated genes associated with the 2-AP biosynthetic pathway GRAPHICAL ABSTRACT