Differently expressed ‘Early’ flavonoid synthesis genes in wheat seedlings become to be co-regulated under salinity stress

Synthesis of flavonoid compounds in plants is associated with their response to environmental stress; however, the way in which the transcription of the relevant structural genes is regulated in stressed plants is still obscure. Transcription of the ‘early’ flavonoid synthesis genes Chi-1 and F3h-1 in the wheat coleoptile was investigated by quantitative real-time PCR in seedlings exposed to 100 mM or 200 mM NaCl. Under mild stress, transcript abundance of both Chi-1 and F3h-1 was increased significantly after six days of exposure. Under severe stress, the level of transcription was the same or even lower than that seen in nonstressed seedlings. In non-stressed conditions, the transcription patterns of Chi-1 and F3h-1 were quite distinct from one another, whereas under stress they became similar. An observed alteration in structural genes regulation mode under stress conditions may optimize flavonoid biosynthesis pathway to produce protective compounds with maximum efficiency