The effect of elevated carbon dioxide concentration on cyanophage PP multiplication and photoreactivation induced by a wild host cyanobacterium

One trend resulting from global climate change is the apparent increase in atmospheric carbon dioxide concentration. The effect of elevated carbon dioxide concentration on the relationship between cyanophages and their hosts in the aquatic ecosystem is far from enough. Using a wild host (cyanobacterium, Leptolyngbya sp.) of cyanophage PP, we investigated the multiplication and photoreactivation of cyanophage PP induced by the wild host at two carbon dioxide concentrations (370 ppm (low) and 740 ppm (high)). The wild host's growth rate and cyanophage PP's adsorption ratio and burst size were greater at the high carbon dioxide concentration. The photoreactivation ratio of cyanophage PP induced by the wild host also increased at a high concentration. These results indicated that the infection capability of cyanophage PP was improved at the same time that growth of its host was enhanced at a high carbon dioxide concentration. Further research should be carried out to test whether the natural balance of the cyanophage–host system could be affected by elevated carbon dioxide concentrations.