Prevalence and molecular characterization of root-knot nematodes (Meloidogyne spp.) and pepper mottle virus (PepMoV) infecting chilli in Punjab

Abstract

Chilli (Capsicum annuum L.), an economically important crop of the Solanaceae family, is highly susceptible to various biotic stresses, particularly root-knot nematodes (RKN) and viral diseases, leading to significant yield losses. A comprehensive survey was conducted across major chilli-growing districts of Punjab to assess the prevalence of RKN and pepper mottle virus (PepMoV). The highest incidence of RKN (70%) was recorded in Malerkotla, whereas the lowest incidence (19.20%) was observed in Ferozepur. Similarly, PepMoV incidence was highest in Malerkotla (74%) and lowest in Bathinda (10.67%). Morphological characterization of RKN populations was performed through perineal pattern analysis, and species identification was further confirmed using sequence characterized amplified region (SCAR) species-specific primers targeting Meloidogyne incognita and M. javanica. Detection of PepMoV was initially carried out using enzyme-linked immunosorbent assay (ELISA) and subsequently validated through immunocapture reverse transcription polymerase chain reaction (IC-RT-PCR) using potyvirus-specific primers. The findings reveal the widespread occurrence and high incidence of RKN and PepMoV in Punjab, emphasizing the urgent need for developing and implementing integrated disease management strategies to minimize yield losses and ensure sustainable chilli production.