How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

Winter Wheat Yields in a Warmer Yangtze Delta Plain of China
Tian, Y., Chen, J., Chen, C., Deng, A., Song, Z., Zheng, C., Hoogmoed, W. and Zhang, W. 2012. Warming impacts on winter wheat phenophase and grain yield under field conditions in Yangtze Delta Plain, China. Field Crops Research 134: 193-199.

The authors write that "more than 20% of the world's food consumers depend on wheat (Triticum aestivum L.), which is produced on an area of over 200 million hectares worldwide (Ortiz et al., 2008)." In addition, they state that the "winter wheat area accounts for more than 80% of this total," and that "it is typically grown in the seasons of winter and spring where warming is mainly anticipated," further informing us that China is the world's largest producer of winter wheat, and that more than 70% of the crop is sown in the country's eastern provinces on the Yangtze Delta Plain.

What was done
In the words of Tian et al., they "conducted a five-year field warming experiment since 2004 with a facility of Free Air Temperature Increase (FATI) in Nanjing, Jiangsu province," where their objectives were "to investigate the actual responses of winter wheat phenophase, biomass production and grain yield to anticipated warming [~1.5°C] under field conditions," and where "there were no water and nitrogen limitations for winter wheat growth, which is common in East China." This they did for a major local cultivar (Triticum aestivum L. cv Yangmai 11) that they describe as having "high yield potential."

What was learned
The eight researchers report that the 1.5°C increase in temperature significantly advanced crop phenophases, leading to a reduction in the length of the entire growth period of about ten days, with the result that grain yields rose due to "the mitigation of low temperature limitation during the pre-anthesis phase and to the avoidance of hot-dry stress during the post-anthesis phase." In addition, they indicate that the areas of flag leaves and total green leaves at anthesis, as well as the 1000-grain weight of the plants, were 36.0, 19.2 and 5.9% higher in the warmed plots than in the unaltered control, respectively. And the net effect of these several warmth-induced changes was a mean grain yield increase of 16.3%.

What it means
Simply put, Tian et al. correctly conclude that "anticipated warming may facilitate winter wheat production in East China," where it will surely be needed in the years and decades ahead.

Ortiz, R., Sayre, K.D., Govaerts, B., Gupta, R. Subbarao, G.V., Ban, T., Hodson, D., Dixon, J.M., Ortiz-Monasterio, J.I. and Reynolds, M. 2008. Climate change: Can wheat beat the heat? Agriculture, Ecosystems and Environment 126: 46-58.

Reviewed 13 February 2013