Infectivity and the phylogenetic relationship of a mastrevirus causing chickpea stunt disease in India

Abstract

Dicot-infecting mastreviruses affect chickpea (Cicer arietinum) plants by causing extreme stunting of the plant and leaf lamina reduction. Chickpea stunt disease (CSD) is presently known to occur in Africa, the Middle East and Asia. Although the disease was first recorded in India, little was known about the pathogen causing the disease. In this study we determined the complete nucleotide sequence of the mastrevirus associated with CSD in the region of Delhi. The genomic component of the virus was cloned using a rolling circle amplification (RCA) method. The virus isolate was found to show 99% sequence identity with the Chickpea chlorotic dwarf Pakistan virus. The complete tandem dimeric construct of the virus was found to be highly infectious to chickpea, and induced severe stunting of the plant, leaf smalling, drying, and the eventual death of the plant. Phylogenetic analysis of all the chickpea-infecting mastreviruses helped to distinguish the current differences between viruses originating from Africa, the Middle East, Asia and Australia.