Role of Antioxidants in the Management of Chilli Leaf Curl Virus in Chilli Using Beneficial Fungal Root Endophyte Piriformospora indica

Chilli leaf curl virus disease caused by Chilli leaf curl virus (ChiLCV) is considered as the most damage-causing for chilli crop, resulting in a cent per cent yield loss when affected at the early crop stage. Piriformospora indica (synonym Serendipita indica), a root endophytic fungus, enhances plant resilience against biotic and abiotic stresses. This study analyses the effect of P. indica against ChiLCV as a pot culture study under green net house conditions using Completely Randomized Design (CRD) layout in the Department of Plant Pathology, College of Agriculture, Padannakkad from August 2022 to January 2023. Chilli seeds colonized in P. indica-enriched potting mixtures exhibited earlier germination than non-colonized seeds. ChiLCV was introduced to chilli plants pre and post-colonized with P. indica and observed for disease incidence. Chlamyodspores of P. indica were observed in the root cortical region five days after co-cultivation (DAC). In the two pot culture experiments conducted, plants pre-colonized with P. indica followed by graft transmission of the virus after 15 days expressed a low vulnerability index (V.I. - 25) against non-colonized, grafted plants (V.I. – 64). Colonization of P. indica (2 days) after graft transmission of the virus recorded a V.I. (36), while non-colonized grafted plants recorded a V.I. of 65. The endophyte colonized plants exhibited elevated ROS scavenging enzyme activity (Catalase, Peroxidase, Superoxide dismutase and Phosphatase) compared to non-colonized ones which was confirmed by enzyme activity analyses and ROS staining techniques. Endophyte colonized chilli plants had exhibited more resilience towards ChiLCV thereby proving that it could be exploited in future towards cultivating disease resistant plants. This study underscores the role of P. indica in managing chilli leaf curl disease by boosting ROS-scavenging enzyme production, offering a promising avenue for disease mitigation.