Fig. 7

Expression pattern of the five salt-induced PPR genes. A Phylogenic analysis of the rice PPR genes identified in this study using the neighbor-joining method with MEGA version 11 by alignment of the gene sequences with MUSCLE algorithm. B Confirmation of the salt-induced PPR genes of RNA-seq data by qPCR assays. Hydroponic cultured two-week-old seedlings were treated with 0 or 140 mM NaCl for 2d followed by RNA extraction and cDNA synthesis. Expression level of each gene without salt stress was taken as 1. Actin1 was used for internal control and all the values are means ± SE from three independent biological determinations. Student’s t test was used for comparing the relative expression of each PPR genes of wild-type plants under salt stress with those of wild-type plants grown under non-stressful conditions. C Expression of the five salt-induced PPR genes in response to ABA, PEG, drought and cold treatment. Hydroponic cultured two-week-old seedlings were treated with 0 or 10 µM ( ±) ABA, 100 mM PEG and cold stress for 5 h or drought stress for 2 h. The material was collected at the indicated time and used for total RNA extraction. Expression level of each gene without stress treatment was taken as 1. Actin1 was used for internal control and all the values are means ± SE from three independent biological determinations. Student’s t test was used for comparing the relative expression of each PPR genes of wild-type plants under stress treatments with those of wild-type plants grown under non-stressful conditions. D Expression level the five PPR genes were detected in different tissues by qPCR assays. Expression level of each gene in root was taken as 1. Actin1 was used for internal control and all the values are means ± SE from three independent biological determinations. Duncan’s multiple range test was used and different letters represent significant differences at P < 0.05