Transcriptomic Insights (3'-RNA-Seq) to deciphering drought resilience in field-grown Cassava Across Season Transitions

Cassava is a perennial plant cultivated in an annual cycle, and is, therefore exposed to stresses related to changes in temperature and water deficiency/excess before harvest. In this study, we investigated the molecular basis of field-grown cassava adaptation to the season transitions. We identified seasonally regulated differentially expressed genes from rainy to dry season and subsequent transition from the dry to rainy season through gene expression profiling of four genotypes at three timepoints. Gene Ontology terms and KEGG pathways enrichment analysis revealed an emphasis on stress response processes. Transcription factor (TF) enrichment analysis indicated a typical stress response regulation, with significantly represented TF target binding motifs in the differentially expressed gene sets. The study also highlights elements related to stress perception, signal transduction, and activation of stress-responsive pathways as a fingerprint of the stress-response cascade during seasonal changes. These findings contribute insights into climate-adaptive traits, aiding in identifying drought tolerance, pest and disease resistance, heat stress resilience, and high water-use efficiency. This knowledge also sets the foundation for future research on the molecular functional characterization of putative and uncharacterized co-associated genes in season transitions. This research will ultimately advance our understanding of cassava's response to environmental fluctuations and pinpoint potential gene targets for crop improvement strategies to deliver climate-resilient crops.