Comparison of salinity effects and medium of TMRL, Gillard and Conway cultivations on density and bloom of Chlorella vulgaris alga in vitro

In order to compare the effect of cultivation medium and salinity on the growth process of Chlorella vulgaris alga, we used a factorial design 3 × 4 (4 is salinity level, 15, 20, 25 and 30 ppt and 3 types of TMRL cultivation medium, Gillard and Conway). In these experiments, 12 treatments were compared. All of treatments had three repeats. The experiments lasted 12 days. According to the results, the most density was for the Gillard at salinity of 25 ppt with average of 125/30×106 ±0/87×106 cell/ml and the lowest density was for Conway in salinity of 15 ppt with average of 37/18×106 ±1/39×106 cell/ml, and there was a significant difference between them (p<0/05). Also the most growth rate in the first day was to the tenth was for Gillard with average 0/536 ±0/5 at salinity of 20 ppt and the lowest of it was for Conway with average of 0/401 ±1/39 at salinity 15 ppt, and a significant difference was seen (p<0/05). This significant difference was also between Gillard, TMRL and Conway (P<0/05). So to produce biomass and high density of Chlorella, salinity of 15 ppt and 20 ppt was better than the other salinities and Gillard cultivation medium at 200 ppt provides better conditions than others to produce a higher and better Chlorella in vitro; but at out cultivation conditions, TMRL medium at salinity of 20 ppt can be better than Conway medium.