Study the expression pattern of PdumiR160a, PdumiR168 and PdumiR171a and their target genes in reproductive tissues of almond in response to cold stress

Cold spring frost is considered as the most important environmental constraint for almond and due to damage to reproductive tissues annually, it causes significant damage to its product. Since little information is available regarding the molecular response of this plant to the frost stress and considering the important role of regulatory microRNA (miRNAs) in many regulatory networks, based on the data from RNA and sRNA sequencing analysis of almond, three microRNA namely, PdumiR160a, PdumiR168 and PdumiR171a with their target genes were selected as cold stress-responsive microRNA. Confirmation of miRNAs expression patterns by quantitative real-time PCR (RT-qPCR) was performed in reproductive tissues of cold-tolerant genotype (H) alongside a sensitive variety (Sh12) under two stress conditions of 0 and -2 ° C. The results showed the negative regulatory role of two miRNAs in response to both cold stresses, but unlike the H genotype, the positive regulatory role of PdumiR168 and PdumiR171a were revealed under cold stress in both reproductive tissues of Sh12 variety. Pearson correlation test showed a negative correlation between PdumiR160a and PduARF18 under both cold stress treatments in the reproductive tissues of Sh12 variety. However, the negative correlation was observed between PdumiR168 and PduAGO1 in ovary tissue of H genotype under two cold stress conditions. Also, in this study, the negative regulatory role of PdumiR171a on the PduSCL6 target gene was revealed under -2 ° C in ovary tissue of H genotype and both reproductive tissues of Sh12 variety.