The Cancer-Kale Connection: What's CO2 Got To Do With It?
La, G.-X, Fang, P., Teng, Y.-B, Li, Y.-J and Lin, X.-Y. 2009. Effect of CO2 enrichment on the glucosinolate contents under different nitrogen levels in bolting stem of Chinese kale (Brassica alboglabra L.). Journal of Zhejiang University Science B 10: 454-464.
Working with seedlings of Chinese kale (Brassica alboglabra L. var. Sijicutiao), the five scientists placed them in pairs in 1.8-L pots "fixed in a foam cavity with sponge" within growth chambers maintained at either 350 or 800 ppm CO2, where the plant's roots were immersed in culture solutions treated with either 5.0 mmol nitrogen (N) per L (low N), 10 mmol N per L (medium N), or 20 mmol N per L (high N) and allowed to grow for 35 days, after which the plants were separated into their primary morphological parts and weighed, while their bolting stems were ground into powder for glocosinolate analyses.
"Regardless of N concentration," say the researchers in describing their findings, the elevated CO2 treatment "significantly increased plant height [15.64%], stem thickness [11.79%], dry weights of the total aerial parts [11.91%], bolting stems [15.03%], and roots [16.34%]." In addition, they report that the elevated CO2 increased the total GS concentrations of the bolting stems in the low and medium N treatments by 15.59% and 18.01%, respectively, compared with those at ambient CO2, although there was no such effect in the high N treatment. Thus, in terms of the total amount of GS production within the bolting stems of Chinese kale, these results suggest that increases of 33 to 36% may well be obtained for plants growing in low to medium N conditions in response to a 450-ppm increase in the atmosphere's CO2 concentration.
These results certainly bode well for people who are wise enough to generously partake of Chinese kale -- and, in all probability, other cruciferous vegetables as well -- especially in the CO2-enriched world of the future that seems destined to become a reality, in spite of all that some might perversely do in striving to prevent it.
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