Antifungal Activity and Role of Terminalia Extracts in Imparting Resistance in Barley against Spot Blotch by Modulating Metabolic Defence Mechanisms

The objective of the current investigation was to examine the effects of botanically induced resistance against the Bipolaris sorokiniana causing spot blotch disease in susceptible barley cultivar (PL 426). Different concentrations of botanical extracts prepared from leaf, fruit and bark of Terminalia bellerica and Terminalia chebula were tested against B. sorokiniana using poisoned food approach. The ethanolic and aqueous fruit extracts resulted in more than 70% mycelial inhibition of B. sorokiniana. The foliar spray of promising doses of botanical extracts was done 2 days prior to inoculation under in-vivo conditions. The physiological and biochemical variations were recorded after treatments from 1 to 7 Days After Treatment (DAT). Foliar spraying of botanical extracts resulted in an increase in total phenol content in inoculated barley plants from 1 to 7 DAT. The malondialdehyde content was significantly lower in plants treated with botanicals as compared to inoculated and un-inoculated controls. The activity of peroxidase and phenylalanine ammonia lyase was significantly higher in all plants sprayed with botanical extracts as compared to the controls. Furthermore, botanicals reduced the percentage of disease severity in the treated plants while increasing the percentage of yield increase. Plants treated with T. chebula fruit extracts had the highest yield increase, followed by T. bellerica fruit extracts. From the present study, it can be concluded that the fruit extracts of T. chebula and T. bellerica are a promising approach for the eco-friendly management of spot blotch.

Antifungal Activity and Role of Terminalia Extracts in Imparting Resistance in Barley against Spot Blotch by Modulating Metabolic Defence Mechanisms Keywords:

Bipolaris sorokiniana , Hordeum vulgare L. , Poisoned food approach , Resistance to spot blotch.