Flowering onset time is regulated by microRNA-mediated trehalose-6-phosphate signaling in Cajanus cajan L. under elevated CO₂

CO₂ levels are known to have an impact on plant development and physiology. In the current study, we have investigated the effect of elevated CO₂ on flowering and its regulation through miRNA mediated sugar signaling. We also unraveled small RNA transcriptome of pigeonpea under ambient and elevated CO₂ conditions and predicted the targets for crucial miRNAs through computational methods. The results have shown that the delayed flowering in pigeonpea under elevated CO₂ was due to an imbalance in C:N stoichiometry and differential expression pattern of aging pathway genes, including SQUAMOSA PROMOTER BINDING PROTEIN-LIKE. Furthermore, qRT PCR analysis has revealed the role of miR156 and miR172 in mediating trehalose-6-phosphate dependent flowering regulation. The current study is crucial in understanding the responses of flowering patterns in a legume crop to elevated CO₂ which showed a significant impact on its final yields. Also, these findings are crucial in devising effective crop improvement strategies for developing climate resilient crops, including pigeonpea.