The ozone stress transcriptome of pepper (Capsicum annuum L.).

We used cDNA microarrays to monitor the transcriptome of ozone stress-regulated genes (ORGs) in two pepper cultivars [Capsicum annuum cv. Dabotop (ozone-sensitive) and Capsicum annuum cv. Buchon (ozone-tolerant)]. Ozone stress up- or down-regulated 180 genes more than three-fold. Transcripts of 84 of these ORGs increased, transcripts of 88 others diminished, and those of eight either accumulated or diminished at different time points in the two cultivars or changed in only one of the cultivars. 67% (120) of the ORGs were regulated differently in ozone-sensitive and ozone-tolerant peppers, most being specifically up-regulated in the ozone-sensitive cultivar. Many were also represented in the plant defense transcriptome against non-host pathogen infection, and some in the transcriptomes for cold, drought, and salinity stresses.