A systematic review of single-cell RNA sequencing applications and insights in Oryza sativa response to environmental stresses.

The use of single-cell RNA sequencing (scRNA-seq) in plant research has improved our capacity to identify transcriptional heterogeneities across diverse tissues. This method has been extensively used for numerous plant species in recent years. While many reviews have focused on single-cell research in Arabidopsis, there is a notable absence of comprehensive reviews addressing scRNA-seq applications in rice. This review provides a systematic overview of scRNA-seq studies conducted in rice between 2017 and 2024. It highlights recent advancements in transcriptomic technologies, including ATCT-seq, snRNA-seq, and Stereo-seq. The review also elucidates the role of single-cell transcriptomics across various rice tissues-roots, leaves, florets, and seeds-focusing particularly on the plant's responses to different stresses such as low nitrogen availability, high salinity, and iron deficiency, and resistance to the brown planthopper (BPH). The mesophyll cell population and chlorophyll abundance per mesophyll cell were reduced on high-salinity treatment (200 mM additional NaCl for three days). The cell numbers of procambium, guard cell, mestome sheath cell, and phloem were different between the BPH-susceptible and BPH-resistant rice varieties. Collectively, this review provides insights into how the integration of scRNA-seq technology can contribute to crop improvement strategies.