PHOTOSYNTHETIC AND RESPIRATION RATE OF HAEMATOCOCCUS PLUVIALIS

Photosynthetic and respiration rate of Haematococcus pluvialis cultured in modified MCM medium under artificial conditions was calculated by measuring the rate of oxygen production and consumption in 1994 in Qingdao. The results show that 1) both photosynthetic rate and respiration rate are typically associated with light intensity and temperature; 2) light intensity at photosynthetic saturated point of motile cells is 260, 320, 320μE/(m 2·s),respectively when cultured at 17℃, 25℃ and 33℃, meanwhile, light intensity at photosynthetic compensation points is 80, 70, 100μE/(m 2·s); and 3) photosynthetic capacity increases with light intensity until light saturated point,and then decreases with further increase of illumination which is called photoinhibition. The results also indicate that cell development stages of this unicellular alga play an important role in photosynthetic and respiration rate, that light intensities at compensation point and saturated point of non motile cells are 90 and 360μE/(m 2·s),both higher than those of motile cells, whereas both photosynthetic capacity and respiration rate of non-motile cells are lower than those of motile cells. Based on the above results and exact natural environment discussed, radiation for each cell ranging from 200 to 320μE/(m 2·s) and large temperature difference between day and night are expected by various means of regulation such as cell density, culture depth, mixing and so on, and are valuable for the cultivation of this algae.