BEIJING, March 19 (Xinhua) -- Researchers have disclosed that long-term exposure to carbon dioxide could enhance grain yield but reduce grain quality in wheat.

　　A research group from Northeast Institute of Geography and Agroecology of Chinese Academy of Sciences cooperated with overseas researchers to investigate grain yield and quality in wheat.

　　The wheat experienced one generation which grew in elevated carbon dioxide concentration and was harvested in 2014 and four generations which were harvested in 2017.

　　Researchers found that the grain yield was enhanced by carbon dioxide concentration, while the exposure to carbon dioxide concentration over four generations caused a larger reduction in grain nitrogen, kalium, calcium, protein, and total amino acid concentrations, according to their study published in the journal Environmental and Experimental Botany.

　　The results indicated that the exposure to carbon dioxide concentration in multiple generations could enhance grain yield but exacerbate grain quality reduction in wheat.

　　The short-term plant response to carbon dioxide concentration could not estimate the long-term response of wheat crops to a future carbon dioxide enriched environment, said the study.