Flavonoid biosynthetic pathway and cereal defence response: An emerging trend in crop biotechnology

The flavonoid pathway, derived from the phenylpropanoid and acetyl CoA and malonyl CoA pathways, gives rise to a diverse array of compounds such as is oflavonoids, anthocyanins, proanthocyanidins, etc. that are attributed with a multitude of biological functions. There is an increasing evidence on th e role of flavonoids in defence response in many plant species though the e xact mechanism is yet to be defined unequivocally. On the contrary, there i s very little information on the role of flavonoids in cereal defence respo nse. A novel strategy to improve disease resistance in cereals is by the en gineering of the flavonoid pathway for enhancement of specific flavonoids i n selected tissue under pathogen attack. Recent developments in molecular b iology and genetics of flavonoid pathway in several plants would allow one to test its potential in improving disease resistance. Further, the powerfu l molecular techniques and reproducible transformation protocols would enab le the manipulation of the flavonoid pathway in cereals. Transferring allie d pathways, or a part of pathways to target plants seem to be within the re ach of many groups. It is. therefore, time for a second look at this second ary pathway particularly in the context of disease resistance phenomenon.