Implications of exposing mungbean (Vigna radiata L.) plant to higher CO₂ concentration on seed quality

Understanding the crop response to elevated carbon dioxide (e[CO₂]) condition is important and has attracted considerable interest owing to the variability and crop-specific response. In mungbean, reports are available regarding the effect of e[CO₂] on its growth, physiology and yield. However, no information are available on the germination and vigour status of seeds produced at e[CO₂]. Therefore, in the present investigation, mungbean (Virat) was grown in the open top chamber during summer season of 2018 and 2019 to study the implications of e[CO₂] (600 ppm) on quality of the harvested seeds (germination and vigour). The exposure of mungbean plant to e[CO₂] had no major impact on seed quality as the percent viability (normal seedling + hard seeds) was not reduced. However, in one season (2018), the seed germination (normal seedling) was slightly reduced from 72 to 68%, attributed majorly to an increase in the hard seeds (from 13 to 19%), a predominant form of seed dormancy in mungbean. The changes in seed germination were apparent only in first year of the experiment. Accelerated ageing test (AAT) and storage studies revealed no differences in the vigour of seeds produced at ambient and e[CO₂] environments. Also, the seeds from e[CO₂] had low protein and sugar but recorded higher starch content than the seeds from ambient [CO₂].