Identification of two new GRAS transcription factors and expression analysis of these genes in Chenopodium quinoa

<i>Chenopodium quinoa</i> is a relatively new and excellent crop, and its growth is frequently threatened by abiotic stress. <i>GRAS</i> genes are considered to be a plant-specific transcriptional regulatory family, which is essential for controlling aboveground and root development, as well as enhancing tolerance to abiotic stress. Phylogeny, gene structure, genomic location, conserved motif, cis-element, protein interaction, and expression pattern were all comprehensively investigated in this research of the quinoa <i>GRAS</i> genes. According to its structure and phylogenetic characteristics, the identified quinoa 54 GRAS members were divided into 10 subgroups. The distribution of <i>CqGRAS</i> genes on 19 quinoa chromosomes is uneven, with Chr07 and Chr18 having the largest number of genes. The quinoa GRAS family's evolution has been driven by duplication and collinearity among members. Under abiotic stress, 12 selected <i>CqGRAS</i> genes showed significant differential expression. <i>CqGRAS1</i> and <i>19</i> were most sensitive to low temperatures, H₂O₂ treatment highly induced the expression of <i>CqGASS20</i>, and Na₂CO₃ treatment highly induced the expression of <i>CqGRAS23</i>. After conducting tissue quantification, we found that some <i>CqGRAS</i> genes exhibit tissue-specific expression patterns, with <i>CqGRAS19</i> and <i>45</i> being highly expressed in stems and <i>CqGRAS3</i> and <i>32</i> being highly expressed in leaves. In summary, this work gives valuable information for a comprehensive understanding of the functional analysis of the <i>Chenopodium quinoa</i> genome's <i>GRAS</i> gene family and the identification of candidate genes to improve quinoa's resistance to abiotic stress.