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Opiate Production by Poppies
Ziska, L.H., Panicker, S. and Wojno, H.L. 2008. Recent and projected increases in atmospheric carbon dioxide and the potential impacts on growth and alkaloid production in wild poppy (Papaver setigerum DC.). Climatic Change 91: 395-403.

The authors write that "among medicinal plants, the therapeutic uses of opiate alkaloids from poppy (Papaver spp.) have long been recognized," and that "the overall goal of the current investigation was to evaluate the growth and production of opiates for a broad range of recent and projected atmospheric carbon dioxide concentrations using wild poppy (P. setigerum) as a surrogate for P. somniferum.

What was done
Ziska et al. grew well watered and fertilized plants from seed (one plant per 2.6-liter pot filled with a 4:1:1 mixture of sphagnum, perlite and vermiculite) within growth chambers maintained at four different atmospheric CO2 concentrations - 300, 400, 500 and 600 ppm - for a period of 90 to 100 days, while quantifying plant growth and the production of secondary compounds including the alkaloids morphine, codeine, papaverine and noscapine, which were derived from latex obtained from capsules produced by the plants.

What was learned
The three researchers' data indicate that relative to the plants grown at 300 ppm CO2, those grown at 400, 500 and 600 ppm produced approximately 200, 275 and 390% more aboveground biomass, respectively, as best we can determine from their bar graphs. In addition, they report that "reproductively, increasing CO2 from 300 to 600 ppm increased the number of capsules, capsule weight and latex production by 3.6, 3.0 and 3.7 times, respectively, on a per plant basis," with the ultimate result that "all alkaloids increased significantly on a per plant basis."

What it means
Ziska et al. conclude that "as atmospheric CO2 continues to increase, significant effects on the production of secondary plant compounds of pharmacological interest (i.e. opiates) could be expected," which effects, in their words, "are commonly accepted as having both negative (e.g. heroin) and positive (e.g. codeine) interactions with respect to public health." It is the duty of everyone to see that the positive effects prevail.

Reviewed 24 December 2008