Abstract: Pteridophytes (lycophytes and ferns) are the second most diverse lineage of vascular plants on the earth, exceeded only by angiosperms. These plants share several morphological and physiological traits with other vascular and sporophyte plants, and play a vital role in the evolutionary progression of land plants from lower to higher forms. Pteridophytes exhibit many unique biological processes different from other plant groups, and play a pivotal role in the study of plant genome evolution, organ development, reproductive phenomena, and adaptation to changing environment. The swift advancement and implementation of modern sequencing technology has greatly accelerated the sequencing and assembly of whole genomes, and greatly promoted the exploration gene function of pteridophytes. To gain an enhanced comprehension of the present interesting fields and noteworthy development in functional genomics research of pteridophytes, this article provides a thorough overview of the functional investigation of pteridophyte genes from various perspectives. It mainly focuses on the development of organs, reproductive processes, adaptability to the environment, and the synthesis of secondary metabolites. It presents a systematic exploration of the molecular functions of multiple genes, highlighting the practical implementation of gene function research in clarifying the unique biological processes specific to pteridophytes. This highlights the significance of investigating the unique biological phenomena of pteridophytes at the molecular level, as it facilitates a better understanding and utilization of this diverse group of plants. In addition, this article puts forward several recommendations on how to expedite the research on gene function of pteridophytes, and to take advantage of molecular function studies in exploring the biological characteristics of terrestrial plants and expanding the application scope of pteridophytes.

Key words: fern plants, lycophytes, gene, function study, biological trait