Genome‑wide Characterization of the cotton FAR gene family reveals a positive role of GhFAR3 in Verticillium dahliae resistance

Fatty acyl-CoA reductase (FAR) proteins play a crucial role in plant growth and development. Previous studies on FAR proteins primarily focused on their involvement in the synthesis of suberin and waxes, while limited attention has been given to their roles in biotic and abiotic stress responses. In this study, 31 FAR genes were identified across Gossypium arboreum , G. raimondii , G. hirsutum , and G. barbadense . Bioinformatics analyses revealed that cotton FAR genes cluster into three distinct groups, with conserved motifs, exon-coding sequences, and domains among genes within the same group. Promoter analysis identified numerous cis-acting elements associated with plant hormone regulation in GhFAR genes, highlighting their regulatory potential. Gene family expansion was predominantly driven by whole-genome duplication events. Expression profiling demonstrated that FAR genes are expressed in various cotton tissues, with most showing reduced expression under abiotic stresses but significantly increased expression following Verticillium dahliae infection. Functional analysis using virus-induced gene silencing (VIGS) of GhFAR3 revealed that its silencing compromises disease resistance by reducing suberin accumulation in roots. This study provides a comprehensive genome-wide identification and characterization of FAR genes in cotton, emphasizing their potential biological functions. Furthermore, it establishes GhFAR3 as a key player in enhancing cotton resistance to V. dahliae , mediated through suberin biosynthesis in roots.