Identification and distribution of novel badnaviral sequences integrated in the genome of cacao (Theobroma cacao)

Muller, Emmanuelle; Ullah, Ihsan; Dunwell, Jim M; Daymond, Andrew J; Richardson, Megan; Allainguillaume, Jo�l; Wetten, Andy

Abstract

Theobroma cacao is one of the most economically important tropical trees, being the source of chocolate. As part of an ongoing study to understand the diversity of the badnavirus complex, responsible for the cacao swollen shoot virus disease in West Africa, evidence was found recently of virus-like sequences in asymptomatic cacao plants. The present study exploited the wealth of genomic resources in this crop, and combined bioinformatic, molecular, and genetic approaches to report for the first time the presence of integrated badnaviral sequences in most of the cacao genetic groups. These sequences, which we propose to name eTcBV for endogenous T. cacao bacilliform virus, varied in type with each predominating in a specific genetic group. A diagnostic multiplex PCR method was developed to identify the homozygous or hemizygous condition of one specific insert, which was inherited as a single Mendelian trait. These data suggest that these integration events occurred before or during the species diversification in Central and South America, and prior to its cultivation in other regions. Such evidence of integrated sequences is relevant to the management of cacao quarantine facilities and may also aid novel methods to reduce the impact of such viruses in this crop.

• Journal Article Type: Article
• Acceptance Date: Mar 22, 2021
• Online Publication Date: Apr 15, 2021
• Publication Date: Apr 15, 2021
• Deposit Date: Aug 11, 2021
• Publicly Available Date: Aug 11, 2021
• Journal: Scientific Reports
• Electronic ISSN: 2045-2322
• Publisher: Nature Research (part of Springer Nature)
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 1
• Article Number: 8270
• DOI: https://doi.org/10.1038/s41598-021-87690-1
• Public URL: https://uwe-repository.worktribe.com/output/7260629
• Publisher URL: www.nature.com/scientificreports/