Modulation of photosynthate supply by CO₂ elevation affects the post‐head‐emergence frost‐induced grain yield loss in wheat

Abstract

Post‐head‐emergence frost (PHEF) has a detrimental impact on grain yield of wheat, and an enhanced photosynthate supply could alleviate the negative impact. However, modulation of photosynthate availability at different growth stages may exert different effects on the plant physiology and grain yield. The objective of this study was to investigate the roles of the enhanced photosynthate supply by growing the plants at elevated [CO2] (800 ppm) during different growth stages on yield performance of wheat exposed to PHEF. The results showed that the PHEF caused a high grain yield loss in wheat, and an increase in photosynthate supply during the reproductive growth stage mitigated the negative impact, whereas that at vegetative growth stage exacerbated the negative impact of PHEF. The opposite effects exerted by the enhanced photosynthate supply at vegetative stage versus at reproductive stage on yield performance could be associated with its distinguished roles in influencing plant physiology at the two growth stages. The positive effect of the increased photosynthate supply at reproductive stage was due to an improved grain filling and regeneration of effective tillers upon recovery from frost, whereas the negative effects of the enhanced photosynthate supply at vegetative growth stage were primarily due to an accelerated early vegetative growth that increased the sensibility of the plants to PHEF.

Elucidating the source–sink relationships of zinc biofortification in wheat grains: A review

“…These impacts must be considered when designing sustainable or climate‐smart management actions (including breeding) to achieve the goal of biofortification, and to fully understand how forecasted scenarios of climatic change will affect the agricultural and nutritional potential of wheat worldwide. Drought and heat stresses, elevated atmospheric CO 2 concentration, and their interactive effects, influence wheat growth parameters (such as the stomatal conductance, plant water relation, ABA concentrations in leaf and spike, photosynthesis, leaf senescence, and grain yield components) (Li, Kristiansen, Rosenqvist, & Liu, 2019; Li, Li, et al, 2019; Li, Ulfat, et al, 2019). However, it is unclear how these parameters may affect the source–sink relationship of Zn, and what the underlying physiological, biochemical, and molecular mechanisms are.…”

Crop photosynthesis for the twenty-first century

“…Different ploidy levels of chromosomes probably play an important regulatory role in the photosystems and antioxidative systems of plants (Mao et al 2018;Chovancek et al 2021). Despite much successful research, there is still a lack of information on how plants can more efficiently transform solar energy and better fix CO 2 , how plants respond to combined environmental stress factors, and how they will be able to cope with the consequences of climate change in the twenty-first century (Li et al 2019). Therefore, there is a great necessity for reviving research into the ecophysiology of photosynthesis.…”

Impact of elevated CO2 on two contrasting wheat genotypes exposed to intermediate drought stress at anthesis

“…Drought stress at the flowering stage reduces plant performance through reduction in grain number and grain weight (Keipp, Hütsch, Ehlers, & Schubert, 2020; Rajala, Hakala, Mäkelä, & Peltonen‐Sainio, 2011). Elevated CO 2 is reported to maintain the grain number and weight under drought conditions at anthesis (Li, Li, et al, 2019; Li, Li, Zhu, Liu, & Liu, 2018). As expected, here decreases in NSP, number of grains pot −1 , thousand kernel weight (TKW) and grain yield pot −1 (GYP) were observed under drought stress; however, elevated CO 2 did not stabilize the plant yield under drought stress (Table ).…”