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The Photosynthetic Response of Muskmelon to Increases in the Air's Temperature and CO2 Concentration
Reference
Chen, N., Gan, Y. and Wang, G.  2003.  Photosynthetic responses of muskmelon (Cucumis melo L.) to photon flux density, leaf temperature, and CO2 concentration.  Canadian Journal of Plant Science 83: 393-399.

What was done
In both field and greenhouse experiments in northwest China, the authors measured the photosynthetic response of two varieties of muskmelon (Cucumis melo L.) to atmospheric CO2 enrichment, while holding photon flux density and leaf temperature constant at 1400 mol m-2 s-1 and 28°C, respectively.  They also measured the photosynthetic response of muskmelon to leaf temperature, while holding photon flux density constant as before and maintaining the air's CO2 concentration at a constant value of 350 ppm.

What was learned
The authors report that muskmelon photosynthesis responded positively to atmospheric CO2 concentration as it rose from a low of 33 ppm to a high of 1060 ppm, and that it responded positively to leaf temperature as that parameter rose from a low of 8°C to a high of 47°C.

What it means
If the air's CO2 concentration were to rise by another 200 ppm, the authors say this increase "would have positive effects on muskmelon production, because crop photosynthesis would increase by 30 to 40%."  And if the air's temperature was to rise concurrently, the results of their work suggest that muskmelon photosynthesis would increase even more.  For this much-prized plant, therefore, continued increases in the air's temperature and CO2 concentration would be welcome developments.


Reviewed 3 September 2003