Genetic transformation is an important strategy for enhancing plant biomass or resistance in response to adverse environments and population growth by imparting desirable genetic characteristics. Research on plant genetic transformation technology can promote the functional analysis of plant genes, the utilization of excellent traits, and precise breeding. Various technologies of genetic transformation have been continuously discovered and developed for convenient manipulation and high efficiency, mainly involving the delivery of exogenous genes and regeneration of transformed plants. Here, currently developed genetic transformation technologies were expounded and compared. Agrobacterium-mediated gene delivery methods are commonly used as direct genetic transformation, as well as external force-mediated ways such as particle bombardment, electroporation, silicon carbide whiskers, and pollen tubes as indirect ones. The regeneration of transformed plants usually involves the de novo organogenesis or somatic embryogenesis pathway of the explants. Ectopic expression of morphogenetic transcription factors (Bbm, Wus2, and GRF-GIF) can significantly improve plant regeneration efficiency and enable the transformation of some hard-to-transform plant genotypes. Meanwhile, some limitations in these gene transfer methods were compared including genotype dependence, low transformation efficiency, and plant tissue damage, and recently developed flexible approaches for plant genotype transformation are discussed regarding how gene delivery and regeneration strategies can be optimized to overcome species and genotype dependence. This review summarizes the principles of various techniques for plant genetic transformation and discusses their application scope and limiting factors, which can provide a reference for plant transgenic breeding.

MicroRNAs (miRNAs) are key post-transcriptional regulators of gene expression and play important roles in plant development and reproduction. Liriodendron chinense, a representative woody species of Magnoliaceae, produces a large quantity of pollen but exhibits low natural seed set. Despite numerous studies on factors influencing its low seed production, the molecular mechanisms underlying this reproductive limitation remain poorly understood. Here, we performed small RNA sequencing and transcriptome analyses across five tissues of L. chinense, including leaf, calyx, petal, pistil, and pollen. Genome-wide identification yielded 688 miRNAs, comprising both conserved and species-specific members. Expression-based clustering revealed that miRNAs are organized into distinct, tissue-associated modules rather than being uniformly expressed across organs. Among these, a pollen-enriched miRNA module was clearly separated from those associated with leaves and other floral tissues. By integrating sRNA-seq and RNA-seq data, we identified miRNA–target pairs displaying anticorrelated expression patterns, providing expression-level support for miRNA mediated regulation. In pollen, two complementary regulatory modes were observed: low-abundance miRNAs associated with highly expressed target genes, and highly expressed miRNAs associated with repressed targets. The predicted targets of pollen-associated miRNAs were enriched in biological processes central to pollen development, including signal transduction, polarity establishment, vesicle trafficking, and cell wall biogenesis. Overall, this study provides a comprehensive, tissue-resolved view of miRNA expression and pollen-associated miRNA–target relationships in L. chinense, offering candidate regulatory modules for future functional studies of pollen development.