Responses of wheat and rice to factorial combinations of ambient and elevated CO₂ and temperature in FACE experiments

Abstract

Elevated CO2 and temperature strongly affect crop production, but understanding of the crop response to combined CO2 and temperature increases under field conditions is still limited while data are scarce. We grew wheat (Triticum aestivum L.) and rice (Oryza sativa L.) under two levels of CO2 (ambient and enriched up to 500 μmol mol(-1) ) and two levels of canopy temperature (ambient and increased by 1.5-2.0 °C) in free-air CO2 enrichment (FACE) systems and carried out a detailed growth and yield component analysis during two growing seasons for both crops. An increase in CO2 resulted in higher grain yield, whereas an increase in temperature reduced grain yield, in both crops. An increase in CO2 was unable to compensate for the negative impact of an increase in temperature on biomass and yield of wheat and rice. Yields of wheat and rice were decreased by 10-12% and 17-35%, respectively, under the combination of elevated CO2 and temperature. The number of filled grains per unit area was the most important yield component accounting for the effects of elevated CO2 and temperature in wheat and rice. Our data showed complex treatment effects on the interplay between preheading duration, nitrogen uptake, tillering, leaf area index, and radiation-use efficiency, and thus on yield components and yield. Nitrogen uptake before heading was crucial in minimizing yield loss due to climate change in both crops. For rice, however, a breeding strategy to increase grain number per m(2) and % filled grains (or to reduce spikelet sterility) at high temperature is also required to prevent yield reduction under conditions of global change.

Regional disparities in the beneficial effects of rising CO2 concentrations on crop water productivity

“…These include one additional site for rice at Ibaraki, Japan (Zhang et al, 2013) and two additional sites for wheat at Jiangsu and Beijing, China (Liu et al, 2008, Yang et al, 2006, 2009. We also collected additional data for soybean (Morgan et al, 2005), rice (Kim et al, 2003, Shimono et al, 2008 and wheat (Cai et al, 2015, Han et al, 2015 at the sites reported in Table S1.…”

Nitrogen Use Efficiency in Rice

“…Growth and yield of rice plants are markedly affected by increased CO 2 concentration and temperature [109,110]. Numerous studies have indicated that an increase in CO 2 generally stimulates photosynthesis, reduces stomatal conductance, and changes the rhizosphere conditions of plants, leading to increases in biomass and yield of crops [111][112][113], whereas an increase in temperature accelerates crop phenological development and shortens grainfilling period of crops, leading to decrease grain yield and reduce crop production in many regions of the world [114,115].…”

“…Furthermore, high temperature, if occurring at critical stages of crop development (such as meiosis and flowering stages), reduces spikelet fertility [115]. Owing to elevated CO 2 under future climate change is associated with an increase in air temperature, many studies about plant response to the interaction of CO 2 and temperature have been reported [109,110,116]. Increases in CO 2 were unable to compensate for the negative impact of increases in temperature on biomass and yield in rice [109,110].…”

Managing Water and Soils to Achieve Adaptation and Reduce Methane Emissions and Arsenic Contamination in Asian Rice Production

“…Cheng et al [20], also using controlled environment chambers, showed that high night temperatures limit grain setting of the IR-72 cultivar, thus reducing the yield enhancing advantages of higher CO 2 concentrations. Cai et al [36] found that higher temperatures fully offset the potential gains in rice yields from higher levels of CO 2 , in a two-year, free-air CO 2 enrichment (FACE) experiment in Jiangsu Province, China. Rice yields were reduced by 35% in 2013 and by 17% in 2014, at increased levels of both CO 2 and temperature.…”

“…The number of filled grains per m 2 was significantly smaller in the presence of higher CO 2 and higher temperature. The authors recommend research to increase the proportion of filled grains (or spikelet fertility) and grain number per m 2 , to prevent yield reductions due to climate change [36]. Wang et al [37] report an average 4.7% reduction in rice yield, when both CO 2 and temperature were increased, over the course of a four-year field experiment with a japonica hybrid cultivar, also in Jiangsu Province.…”