Submitted to: Rice Technical Working Group Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 15, 2007
Publication Date: August 15, 2008
Citation: Ziska, L.H., Mcclung, A.M. 2008. Rising carbon dioxide as a selection factor in rice/red rice competition. Rice Technical Working Group Meeting Proceedings. 142.
Carbon dioxide (CO2), along with sunlight, water, and nutrients constitutes one of the four resources needed for plants to grow. As such, the sudden increase in its concentration in the atmosphere (up 22% since 1960) could be exploited in order to boost crop yields. However, the rise in CO2 is indiscriminate with respect to plant species and could stimulate not only the crop, but weed species as well. To determine if recent and projected increases in atmospheric carbon dioxide differentially affected crops and weeds, we examined six different varieties of cultivated and wild (weedy) rice to three different CO2 concentrations that correspond roughly to the 1950s, the current concentration, and the concentration anticipated by 2050. Overall, we found that as CO2 increases, the wild or weedy rice was stimulated more than the cultivated rice. This may increase the competitiveness of weeds in rice, with negative consequences for rice yield. However, since both wild and cultivated rice are closely related, it may be possible to transfer desirable, CO2 sensitive characteristics from the wild to cultivated rice plant. This data and its inference for food security will be of interest for policy makers, scientists, agronomists, and plant breeders