Characterizing the expression patterns of short-day flowering genes, the manipulation of their expression using red-far red wavelengths, and the resulting phenotype/ chemotype inCannabis sativa

Abstract

Cannabis is a short day (SD) plant whose inflorescences produce valuable medicines. By studying the mechanisms of photoperiodic flowering initiation in cannabis, we may develop new methods of improving cultivation. In SD plants, CONSTANS, which is enhanced by CDL gated proteins that are expressed during short days, acts as a bifunctional regulator of flower inhibition or genesis via FT (florigen). These genes are downstream of phytochrome, which may be activated by horticultural lighting conditions like red (R, 660nm) to far red (FR, 700+nm) wavelength ratios. This study demonstrates that gene expression can be manipulated using high and low R:FR ratios, and characterizes the expression levels of CONSTANS, FT, PRR37, and SOC1 in cannabis over the first 14 short days. It also demonstrates the resulting effect on cannabinoid production and biomass yields.