Effects of green light spectrum on growth and gene expression profiles of green algae Haematococcus pluvialis

This study was carried out to reveal both growth and genetic effects of different ratios of green light on Haematococcus pluvialis cultures. H. pluvialis cells were grown and examined on 2 different experimental setups. Although there were differences in green light ratios in both experimental setups, cultures were grown at a total light intensity of 20 µmol m-2 s-1. In the first experiment setup, White light (W) treatment was used as the control group. In another treatment (G/2), the green light ratio in the white light illumination has been reduced by 50%. In the last treatment (G0), the rate of green light in white light was reduced to 4%. G0 treatment has increased in terms of cell number, chl-a amount, biomass and dry weight compared to other treatments, and there is a statistically significant difference compared to other treatments. In the second experiment setup, Red-Blue (RB) light mixture was used as the control group. In the other treatment has been used G10 as 10% green light supplementation to the RB light mixture. In the last treatment has been used G20 as 20% green light supplementation to the RB light mixture and the research was carried out. When the number of cells, chl-a amount, biomass and expressions of certain genes (PsaB, PsbS, PTOX2 and Rubisco) were examined, G10 treatment was observed more clear and higher growth and more expression levels of genes (except PTOX2 gene). In the G10 treatment was observed significant differences than other treatments as statistically.