Role of Weed Hosts in the Epidemiology of Chilli Leaf Curl Virus (ChiLCV) in Chilli Ecosystems

Abstract

Chilli (Capsicum annuum L.) is an economically important spice and vegetable crop widely cultivated in tropical and subtropical regions. However, its productivity is severely constrained by several viral diseases, among which chilli leaf curl disease caused by begomoviruses is considered one of the most destructive. The present study investigated the role of weed hosts in the epidemiology of chilli leaf curl virus (ChiLCV) in chilli-growing ecosystems around Bengaluru, Karnataka, India. Field surveys were conducted during the 2023–2024 cropping season in major chilli-producing regions including Kolar, Chikkaballapura, and Bengaluru districts. Several weed species growing within and around chilli fields were collected and examined for begomovirus-like symptoms such as leaf yellowing, upward curling, puckering, mosaic patterns, and plant stunting. Molecular detection using coat protein gene-specific primers confirmed the presence of ChiLCV in multiple weed hosts. The results indicated that several weed species act as potential reservoirs of ChiLCV and may facilitate virus survival and dissemination through the whitefly vector Bemisia tabaci. These findings highlight the epidemiological importance of weed hosts in the persistence and spread of chilli leaf curl virus. Effective weed management in and around chilli fields, together with appropriate vector control strategies, is therefore essential for reducing virus inoculum sources and minimizing the incidence of chilli leaf curl disease.