Perilous coexistence: Chilli Leaf Curl Virus and Candidatus Phytoplasma trifolii infecting Capsicum annuum, India

Abstract

Molecular computing was used to investigate the possible causal agents of chilli crop samples showing mixed symptoms of yellow leaf curl and little leaf type diseases in the Uttar Pradesh province, India. Total genomic DNA was extracted from twenty-five samples and amplified by PCR using a universal primer pair for begomovirus and phytoplasma. Mixed infection samples show positive amplified products for begomovirus (DNA-A and betasatellite) and phytoplasma (16S rRNA and Sec A). The identified begomovirus from chilli samples was identified as a strain isolate of the previously described Chilli Leaf Curl Virus (94.2% nucleotide sequence identity), which is known to infect Solanum lycopersicon, in Oman, whereas the 16S rRNA was identified from the source Candidatus Phytoplasma trifolii (99.04% nucleotide sequence identity), which is known to infect Helichrysum flowering plants in India. Subsequently, molecular computing research based on phylogenetic interweaves, putative recombination, amino acid selection, and genetic diversity were investigated, revealing divergent evolutionary patterns with significant variation and recombination events. The majority of the sequence variations observed in begomovirus and phytoplasma were caused via inter- and intra-specific recombination. These findings could be the first in silico combined infection analysis of ChiLCV and Ca.P.trifolii in a chilli crop in India, revealing the potential adaption and evolution of begomovirus and phytoplasma to a new geographic range and crop.