Does moisture stress condition drought heat stress or irrigated condition affect on protein content of grain. The size of grain differs but what is the effect on protein content per gm wt of grain.
Also check https://www.researchgate.net/publication/222033799_Protein_accumulation_and_composition_in_wheat_grains_Effects_of_mineral_nutrients_and_high_temperature
Which study conducted on the effect of drought stress on protein changes of five wheat genotypes and found that in all genotypes the effects of drought stress on seed storage proteins were significant, and in drought stress treatment the seed storage proteins were more than irrigated treatment. Therefore it concluded that seed protein bands are very stable in front of environmental changes.
Also kindly check the following RG link entitled (Heat and Drought Stresses in Wheat (Triticum aestivum L.): Substantial Yield Losses, Practical Achievements, Improvement Approaches, and Adaptive Mechanisms):
Chapter Heat and Drought Stresses in Wheat ( Triticum aestivum L.): ...
I doubt that a definite answer can be given here. Moisture environment is not the only factor that should be taken into account here, What about sunlight? What about fertilization? etc.