Effects of Elevated CO2 on a Pair of Plant Diseases of Trees
Runion, G.B., Prior, S.A., Rogers, H.H. and Mitchell, R.J. 2010. Effects of elevated atmospheric CO2 on two southern forest diseases. New Forests 39: 275-285.
With respect to the pine Fusarium rust study, Runion et al. report that "percent infection was not significantly affected by CO2 concentration," but that in spite of this fact "the percentage of loblolly pine seedlings which died as a result of rust infection was generally significantly lower under elevated CO2 in both runs of the experiment." With respect to the oak Fusarium rust study, they say "the percent of oak seedlings with uredia was consistently lower for seedlings exposed to elevated CO2 in both runs," and that "the percent of oak seedlings with telia was significantly lower for seedlings exposed to elevated CO2 at the 16 and 19 days evaluations in both runs of the experiment." Last of all, with respect to the pine pitch canker study, the four researchers indicate that "the percent of loblolly pine seedlings which developed cankers following inoculation with the pitch canker fungus was consistently lower for seedlings grown under elevated CO2 in both runs of the experiment ... with infection in elevated CO2-grown seedlings remaining about half that of ambient-grown seedlings."
Runion et al. state that the results of their study suggest that "disease incidence -- regardless of pathogen type -- may be reduced as atmospheric CO2 concentration continues to rise," which phenomenon should significantly benefit the two species of trees in the high-CO2 world of the future we seem destined to inherit.