The root transcriptome analyses of peanut wild species Arachis correntina (Burkart) Krapov. & W.C. Gregory and cultivated variety Xiaobaisha in response to benzoic acid and p -cumaric acid stress

Allelopathy is the main cause of continuous cropping obstacles. Peanut wild species Arachis correntina (Burkart) Krapov. & W.C. Gregory is more resistant to continuous cropping obstacle than cultivated peanut, but its molecular mechanism in response to allelochemicals remains unknown. Benzoic acid (BA) and p -cumaric acid (PCA) are known allelochemical. To gain more insight into cellular response to BA and PCA, we applied high-throughput genetic sequencing to study the transcriptome changes of peanut cultivated variety Xiaobaisha and wild species A. correntina in the presence of 2 mM BA and PCA. The result showed that A. correntina resistance to BA and PCA stress was more weaker than Xiaobaisha. BA and PCA decreased significant shoot length and dry matter weight of A. correntina . Differentially expressed genes (DGEs) related to flavonoid biosynthesis, phenylpropanoid biosynthesis, plant–pathogen interaction and plant hormone signal transduction were transcribed less in A. correntina than Xiaobaisha under BA and PCA stress, including the less up-regulated genes involving in phenylpropane and flavonoid biosynthesis, detoxifying enzymes, Auxin responsive protein, WRKY family and Ef-hand, which might contribute to A. correntina ’s weak resistance to BA and PCA stress. The results showed that the resistance to single allelopathic substance might not be the reason for A. correntina resistance to continuous cropping obstacle. In addition, DGEs of both A. correntina and Xiaobaisha were significantly enriched in the pathways associated with isoflavonoid biosynthesis and glutathione metabolism under BA and PCA stress. This was the first report on identification of DGEs under BA and PCA stress between peanut cultivated variety and wild species. The result would be great helpful to insight into the mechanisms of peanut response to allelochemicals stress.