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Peanut is an important oil and economic crop widely cultivated in the world. It has special characteristics such as blooming on the ground but bearing fruits underground. During the peg penetrating into the ground, it is subjected to mechanical stress from the soil at the same time. It has been proved that mechanical stress affects plant growth and development by regulating the ethylene signaling-related genes. In this study, we identified some genes related to ethylene signal of peanut, including 10 ethylene sensors, two constitutive triple responses (CTRs), four ethylene insensitive 2 (EIN2s), four ethylene insensitive 3 (EIN3s), six EIN3-binding F-box proteins (EBFs), and 188 Apetala2/ethylene-responsive factors (AP2/ERFs). One hundred and eighty-eight AP2/ERFs were further divided into four subfamilies, 123 ERFs, 56 AP2s, 6 Related to ABI3/VP1 (RAVs), and three Soloists, of them one hundred and seventy AP2/ERF gene pairs were clustered into segmental duplication events in genome of Arachis hypogaea. A total of 134, 138, 97, and 150 AhAP2/ERF genes formed 210, 195, 166, and 525 orthologous gene pairs with Arachis duranensis, Arachis ipaensis, Arabidopsis thaliana, and Glycine max, respectively. Our transcriptome results showed that two EIN3s (Arahy.J729H0 and Arahy.S7XF8N) and one EBFs (Arahy.G4JMEM) were highly expressed when mechanical stress increased. Among the 188 AhAP2/ERF genes, there were 31 genes with the fragments per kilobase of exon model per million mapped fragments (FPKM) ≥ 100 at least one of the 15 samples of Tifrunner. Among them, three AhAP2/ERFs (Arahy.15RATX, Arahy.FAI7YU, and Arahy.452FBF) were specifically expressed in seeds and five AhAP2/ERFs (Arahy.HGAZ7D, Arahy.ZW7540, Arahy.4XS3FZ, Arahy.QGFJ76, and Arahy.AS0C7C) were highly expressed in the tissues, which responded mechanical stress, suggesting that they might sense mechanical stress. Mechanical stress simulation experiment showed that three AhAP2/ERFs (Arahy.QGFJ76, Arahy.AS0C7C, and Arahy.HGAZ7D) were sensitive to mechanical stress changes and they all had the conservative repressor motif (DLNXXP) in the C-terminus, indicated that they might transmit mechanical stress signals through transcriptional inhibition. This study reveals the regulatory landscape of ethylene signal-related genes in peanut, providing valuable information for the mining of target genes for further study.

Additional file 5: Figure S5. Distributions of Ka, Ks, and Ka/Ks values between landrace and improved cultivar alongside the chromosome.

Additional file 11: Figure S11. Distributions of Gene Ontology terms between landrace and improved cultivar barley. Yellow, green and pink columns represent biological process, cellular component and molecular function, respectively. Terms with P

Additional file 8: Figure S8. Comparisons of genomic features between PSGs and NSGs during the process of barley improvement. The line in the box is the median value, and the lines at the bottom and top of each box are the first (lower) and third (higher) quartiles. Violin plots represent the density of gene numbers. a-n The plots display of Ka, Ks, Ka/Ks, gene length, intron length, exon length, first exon length, exon number, GC content, CAI, CBI, FOP, expression level (FPKM) and tissue specificity (τ) between two selections. Blue and purple boxes represent positively and negatively selected genes, respectively.

Additional file 6: Figure S6. Frequency distributions of genomic features between PSGs and NSGs during the process of barley domestication. a-l The density plots display Ka, Ks, Ka/Ks, gene length, intron length, exon length, first exon length, exon number, GC content, CAI, CBI and FOP between two selections. Blue and purple lines represent positively and negatively selected genes, respectively.

Additional file 9: Figure S9. Identification of TFs and functional enrichment analysis of PSGs between landrace and improved cultivar. a Frequency distributions of transcription factors. Blue and purple columns represent positively and negatively selective genes, respectively. b Word clouds of GO terms of PSGs. The larger word of the term indicates gene numbers that were more enriched. Terms with P

Additional file 7: Figure S7. Frequency distributions of genomic features between PSGs and NSGs during the process of barley improvement. a-n The plots display of Ka, Ks, Ka/Ks, gene length, intron length, exon length, first exon length, exon number, GC content, CAI, CBI, FOP, expression level (FPKM) and tissue specificity (τ) between two selections. Blue and purple lines represent positively and negatively selected genes, respectively.

Additional file 3: Figure S3. Correlations among substitution rates, gene features, codon usage bias and expression patterns between landrace and improved cultivar. Upper Right: the size of the circle represents the magnitude of the correlation coefficient, red reveals positive correlation, and blue reveals negative correlation. One asterisk (*), double asterisk (**) and triple asterisk (***) indicate 0.05, 0.01 and 0.001 significant difference level, respectively. Bottom Left: correlation coefficients are presented as Spearman’s rank correlation test ρ.

Additional file 4: Figure S4. Distributions of Ka, Ks, and Ka/Ks values alongside the chromosome with a bin size of 50 consecutive orthologs. a-c The genomic distributions of Ka, Ks and Ka/Ks values alongside chromosome blocks between wild barleyand landrace. d-e The genomic distributions of Ka, Ks and Ka/Ks values alongside chromosome blocks between landrace and improved cultivar.

Additional file 2: Figure S2. Frequency distributions and correlation analysis of Ka, Ks and Ka/Ks between landrace and improved cultivar. a-c The frequency shows of Ka, Ks and Ka/Ks, respectively. d The correlation between Ks (x-axis) and Ka. e The correlation between Ks (x-axis) and Ka/Ks. f The correlation between Ka (x-axis) and Ka/Ks.