Drought stress has become increasingly significant in the context of climate change, as rising temperatures and altered pre- cipitation patterns exacerbate its impact on crop productivity. MicroRNAs (miRNAs) are a class of small, endogenous RNA molecules, which control the expression of multiple genes and influence plant responses to drought stress. In view of this, the present study was carried out to investigate the involvement of HvmiR396 in the inflorescence growth of barley cultivar Fajr 30, both in normal and drought stress growth conditions. The results showed a significant upregulation of both HvmiR396 and its target gene HvGRF3a in inflorescences of 20 to 40 mm in length, specifically under drought stress. Furthermore, the correlation between HvmiR396, HvGRF3a, and physiological traits during inflorescence development suggests their involvement in regulating genes that encode enzymes responsible for the biosynthesis of osmoprotectants such as proline and photosynthetic pigments, as part of the plant’s response to drought stress. Overall, the findings of this study highlight the importance of HvmiR396 and its target gene (HvGRF3a) as genetic factors contributing to the development of barley inflorescences, while also playing a role in conferring tolerance to drought stress by modulating physiological traits during both vegetative and reproductive growth stages.

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