Biotech Updates

TaCAD12 Gene Contributes to Resistance to Sharp Eyespot Disease in Wheat

November 3, 2016

Sharp eyespot, caused by Rhizoctonia cerealis, is a destructive disease in wheat (Triticum aestivum L.). In Arabidopsis, certain cinnamyl alcohol dehydrogenases (CADs) are known to be related to monolignol synthesis and in plant response to bacterial pathogens. However, little is known about CADs in wheat defense. A research team from the Chinese Academy of Agricultural Sciences, led by Wei Rong, isolated a wheat CAD gene, TaCAD12 and studied its defense role in wheat.

Transcript levels of TaCAD12 in sharp eyespot-resistant wheat lines were significantly higher compared to the gene's transcript levels in susceptible lines. Analysis revealed that TaCAD12 protein is an authentic CAD enzyme and possesses catalytic efficiencies towards both coniferyl aldehyde and sinapyl aldehyde.

A TaCAD12 knockdown in wheat plants significantly repressed the plants' resistance to sharp eyespot, while TaCAD12 overexpression enhanced resistance of the transgenic wheat. Furthermore, certain defense genes and monolignol biosynthesis-related genes were also upregulated in the TaCAD12-overexpressing wheat plants, but down-regulated in TaCAD12-silencing plants.

These results suggest that TaCAD12 positively contributes to resistance against sharp eyespot through regulation of the expression of certain defense genes.

For more information, read the full article in Frontiers of Plant Science.