Impact of Elevated CO<sub>2</sub> on Wheat Growth and Yield under Free Air CO<sub>2</sub> Enrichment

Abstract

Impact of elevated CO 2 (free air CO 2 enrichment) was studied on wheat (Triticum aestivum L. var Kundan) growth, yield and proteome. Elevated CO 2 significantly impacted both underground (+24%) and aboveground (+15%) biomass. Grain weight/plant and harvest index were increased by 35% and 11.4%, respectively under high CO 2 . On the other hand, seed protein content was decreased by 19% under CO 2 enrichment while seed starch and soluble sugar contents were increased by 8% and 23%, respectively. Wheat leaf proteomics revealed that 50 proteins were showing differential expression. Twenty proteins were more abundant while 30 were less abundant. Thirty two proteins were identified by MALDI TOF TOF. More abundant proteins were related to defense, photosynthesis, energy metabolism etc. While less abundant proteins were related to glycolysis and gluconeogenesis. Wheat grain proteomics revealed that out of 49 differentially abundant proteins, 24 were more in abundance and 25 were less in abundance in wheat grains under eCO 2 condition. Thirty three proteins were identified and functionally characterized. They were found to be involved mainly in carbon metabolism, storage, defence and proteolysis. Gluten proteins are the major component of wheat storage proteins. Our results showed that both high and low molecular weight glutenins were more in eCO 2 wheat seeds while there was no change in gliadin evels. This might alter wheat dough strength. Concentration of grain Cr and As was increased at eCO 2 while that of Fe, Cu, Zn and Se were found to be decreased. Dynamics of carbon utilization and metabolic abilities of soil microbes under eCO 2 were significantly altered. Our study showed that altered wheat seed composition is cause for concern vis-à-vis nutrition and health and for industries which may have implications for agriculturally dominated country like India.

Effect of Elevated CO2 on the Growth, Physiological Traits and Biological Yield of Three Genotypes of Wheat (Triticum aestivum L.)

“…The biomass production and water use efficiency of the plants exposed to elevated CO 2 condition too increased. The corresponding results were reported by (Barnes et al, 1995;Kannojiya et al, 2019;Lamichaney et al, 2021;Prakash et al, 2022;Pandey et al, 2017;Singh et al, 2018. Enhanced CO 2 level can lead to positive effects more in C 3 plants compared to C 4 plants (Mishra et al, 2013;Rawat and Melkania., 2015;Pleijel and Hogy, 2015).…”

Propagation of climate model biases to biophysical modelling can complicate assessments of climate change impact in agricultural systems

“…Although this rate was still less than a rate measured through an experimental approach reported by Pandey et al . (), SBCMnSD outputs exhibited positive CO 2 coefficients across almost the entire region, instead of largely negative CO 2 coefficients with NonSBC outputs. Second, the coefficients associated with NonSBC yields varied dramatically, while those with SBCMnSD were much more consistent and closer to those previously reported.…”

Effects of Elevated CO2 and Heat on Wheat Grain Quality

“…It means that proteins and minerals are diluted by the increased photosynthetic assimilation of carbon, which poses a great threat to future food security because the calories in the food may be sufficient but undernourishment with essential mineral nutrients. For example, eCO 2 greatly increased the ratio of C to N by increasing the starch and total NSC concentrations and decreasing grain N concentration in wheat [63]. However, Taub et al [54] found that the magnitude of the negative eCO 2 effect on wheat grains was smaller under high soil N conditions than under low soil N with the decrease of grain protein concentrations by 9.8% and 16.4%, respectively, suggesting that the dilution effect may be compensated by a higher nutrient supply.…”