Identifying New Species of Cassava Mosaic Begomovirus and Ageratum Leaf Curl Cameroon Virus on Pepper (Capsicum annuum L.) in Togo

Abstract

The most damaging and economically important diseases of crops, especially in tropical and subtropical regions are caused by whitefly-transmitted begomoviruses. These viruses are included in the genus Begomovirus of the family Geminiviridae and are responsible for causing crop losses ranging from 30% to 100%. Cassava mosaic disease caused by the white fly transmitted begomoviruses (family Geminiviridae) is a major threat to cassava (Manihot esculenta Crantz) production, which can be intercropped with other plants such as pepper (Capsicum annuum L.). This study aims to identify cassava begomoviruses on other crops in cassava intercropping systems. Thus, foliar samples showing typical symptoms of virus diseases in cassava intercropping systems were collected from pepper and submitted to PCR analysis and direct sequencing. Total DNA was extracted from collected leaves using the DNA minipreparation method. Three begomovirus species ACMV, EACMV and ALCCMV were identified and characterized in samples. Isolates of these species shared respectively 90%, 93%, 74% and 80% nucleotide identities with begomoviruses. These findings show that cassava begomoviruses can infect other crops and will help in understanding the epidemiology related to white fly transmitted begomoviruses in cassava intercropping systems. The occurrence of new begomovirus species on pepper could lead in case of mixed infections with already known begomoviruses infecting this crop to recombinant actions. This study suggests a change in Bemisia tabaci population or its feed habit. Further investigations need to bring more information about cassava mosaic begomoviruses and their relationships with pepper.