Phytohormone jasmonates (JA) play essential roles in plants, such as regulating development and growth, responding to environmental changes, and resisting abiotic and biotic stresses. During signaling, JA interacts, either synergistically or antagonistically, with other hormones, such as salicylic acid (SA), gibberellin (GA), ethylene (ET), auxin, brassinosteroid (BR), and abscisic acid (ABA), to regulate gene expression in regulatory networks, conferring physiological and metabolic adjustments in plants. As an important staple crop, rice is a major nutritional source for human beings and feeds one third of the world’s population. Recent years have seen significant progress in the understanding of the JA pathway in rice. In this review, we summarize the diverse functions of JA, and discuss the JA interplay with other hormones, as well as light, in this economically important crop. We believe that a better understanding of the JA pathway will lead to practical biotechnological applications in rice breeding and cultivation.

Diverse genetic background is essential for genetic analysis and functional genomics research in model plants. In this paper, four novel xiaomi-like mutants, named xiaomi3, xiaomi4, xiaomi5, and xiaomi6, were identified and characterized in different genetic backgrounds. These mutants exhibited an extremely early heading phenotype, with heading occurring around 30-40 days after sowing under natural long-day conditions. Significant reductions in plant height, leaf length, leaf width, panicle length, and panicle diameter were observed in the mutants compared to their corresponding wild-types. Notably, these mutants displayed diverse panicle architectures and hull colors, effectively preventing seed mixing between them. Subsequent investigation under controlled short-day and long-day conditions confirmed the significant early heading phenotype of the mutants. Molecular characterization revealed mutations in the Phytochrome C (SiPHYC) gene, including transposon insertions and a frame shift mutation, were responsible for the extremely early heading phenotype. RNA-sequencing (RNA-Seq) analysis identified 19 differentially expressed genes associated with the extremely early heading phenotype. Additionally, genome-wide InDels and SNPs were identified, providing valuable resources for marker-assisted breeding and genetic studies. These findings advance our comprehension of the genetic and molecular mechanisms underlying SiPHYC mediated photoperiod flowering, and provide valuable resources that will push xiaomi as a C₄ model plant.