Occurrence and molecular characteristics of pedilanthus leaf curl virus complex from the new hosts fenugreek and night jessamine in Pakistan

Abstract

Leaf samples of fenugreek plants with leaf yellowing and night jessamine plants with leaf curling symptoms were collected from the vicinity of the University of the Punjab, Lahore, Pakistan. Two complete begomovirus isolates (QM1A and QM3A) and three complete alphasatellite isolates (QM1-a1, QM1-a2, and QM3-a1) were isolated from fenugreek plants. While two complete begomovirus isolates (RR1A and RR2A) and defective betasatellites were identified from night jessamine plants. The isolates QM1A, RR1A, and RR2A shared maximum nucleotide sequence identities of 92–92.9% with pedilanthus leaf curl virus (PeLCV; AM948961) reported from soybean in Pakistan, while QM3A shared 94.1% nucleotide sequence identity with PeLCV. According to the current recommended guidelines for begomovirus species and strain demarcation, the isolates QM1A, RR1A, and RR2A are new PeLCV strains, hence named “Fenugreek strain.” The alphasatellites isolates QM1-a1 and QM1-a2 shared maximum nucleotide sequence identities of 98.8–98.9% with ageratum yellow vein India alphasatellite (AgYVIA; HG515071) whereas, the QM3-a1 isolate was 98.9% identical with ageratum enation alphasatellite (AEA; HE599396) reported from cotton in Pakistan. The recombination analysis revealed the presence of potential recombination events in the isolated begomovirus and alphasatellites. Sequence variation dynamics results showed that alphasatellites populations are more divergent than PeLCV populations. The study identified a new natural complex between PeLCV and DNA-satellites in two distinct plant species. Co-inoculation of agro-infectious clones confirmed the infectivity potential of all DNA-components in the model plant N. benthamiana. The findings of this study highlight the ongoing spread of PeLCV, lending credence to recent reports that PeLCV is an emerging threat to crop production in the Indo-Pak subcontinent.