Effects of Elevated CO2 and Heat on Wheat Grain Quality.

Xizi Wang,Fulai Liu

doi:10.3390/plants10051027

Abstract

Wheat is one of the most important staple foods in temperate regions and is in increasing demand in urbanizing and industrializing countries such as China. Enhancing yield potential to meet the population explosion around the world and maintaining grain quality in wheat plants under climate change are crucial for food security and human nutrition. Global warming resulting from greenhouse effect has led to more frequent occurrence of extreme climatic events. Elevated atmospheric CO2 concentration (eCO2) along with rising temperature has a huge impact on ecosystems, agriculture and human health. There are numerous studies investigating the eCO2 and heatwaves effects on wheat growth and productivity, and the mechanisms behind. This review outlines the state-of-the-art knowledge regarding the effects of eCO2 and heat stress, individually and combined, on grain yield and grain quality in wheat crop. Strategies to enhance the resilience of wheat to future warmer and CO2-enriched environment are discussed.

Highlights

Global atmospheric concentration of carbon dioxide (CO2 ) is expected to reach levels of 420 ppm (RCP2.6) to 1300 ppm (RCP8.5) by the end of this century (IPCC, 2013) with a concomitant rise in mean global temperature of about 2 ◦ C by 2050 (IPCC, 2014)
Heat stress has a huge impact on both grain yield and grain quality during anthesis and grain-filling phase; most of the studies focused on the heat stress effects on grain yield components [18,81,82], only a few studies investigated the impact of heat stress on grain quality traits [17,18,35,83,84]
ECO2 increases wheat grain yield, its negative impact on grain quality poses a great threat to human nutrition

Summary

Introduction

Global atmospheric concentration of carbon dioxide (CO2 ) is expected to reach levels of 420 ppm (RCP2.6) to 1300 ppm (RCP8.5) by the end of this century (IPCC, 2013) with a concomitant rise in mean global temperature of about 2 ◦ C by 2050 (IPCC, 2014). A general increase in grain yield and a reduction of grain quality of plants grown under eCO2 , especially the decrease of nitrogen (N) concentration and protein contents, have often been reported, leading to the conclusion that eCO2 potentially exacerbates the prevalence of “hidden hunger” for human nutrition [7,8] Another environmental factor, heat waves, limits wheat yields globally [9]. Li et al [22] tested 15 quality parameters and found similar results that environmental factors have large effect on grain yield, while grain hardness and gluten quality-related traits are mainly controlled by genotype They found that drought and heat stress showed contrasting effects on dough rheological properties, where heat stress decreased dough tenacity (increased extensibility), slightly reduced dough strength and increased bread loaf volume while drought stress is the opposite. This review summarizes current knowledge regarding the effects of eCO2 and heat stress on grain yield and quality in wheat and aims to (i) introduce wheat quality traits that are sensitive to abiotic growth conditions, (ii) discuss the impacts of eCO2 and heat stress on wheat grain yield and quality and the underlying mechanisms

Wheat Quality and Grain Protein

The Effects of eCO2 on Wheat Plants and the Mechanisms Behind

The Effects of Heat Stress on Wheat Grain Quality

The Interactive Effects of eCO2 and Heat Stress on Wheat Plants

Findings

Conclusions