Re: Can the roots of plants utilize CO2?

Hi, 

Sorry for replying so late. I searched some information sources, but to my 
knowledge there is no strong evidence that CO2 can be significantly absorbed 
by roots and increase plant growth. Normally the CO2 released from 
respiration will be hydrolized into H2CO3 and then produce H+ as well as 
HCO3-, and the H+ will be exchanged with K+ in soil, let K+ enter the roots. 
So CO2 can help roots absorb inorganic cation. But excess CO2 will result in 
the decrease of pH of soil, and this is harmful for root, just as you said, 
"will cause an anaerobic condition"; I think to provide more CO2 is not a 
good method to increase plant growth. 

Based on some research results, it is believed that the CO2 absorbed by root 
can also take part in photosynthesis by be reduced into malate, when under 
light, the malate can be used for photosynthesis. But the CO2 absorbed by 
root is not in big amount. 

Based on my previous knowledge, CO2 is mainly absorbed and used by 
photosynthetic organ, and usually CO2 will cause acidic environment which is 
not good for plant roots. Actually I am very curious about that ads and the 
theory which it was based on. I am willing to get to know the relative 
research, becuse obviously if it is strong enough, to increase plant growth 
will be very easy. But before I see strong evidence, I would rather no make 
conclusion on their remark.