Insights into Emerging Begomovirus–Deltasatellite Complex Diversity: The First Deltasatellite Infecting Legumes

Abstract

Begomoviruses and associated DNA satellites are involved in pathosystems that include many cultivated and wild dicot plants and the whitefly vector Bemisia tabaci. A survey of leguminous plants, both crops and wild species, was conducted in Venezuela, an understudied country, to determine the presence of begomoviruses. Molecular analysis identified the presence of bipartite begomoviruses in 37% of the collected plants. Four of the six begomoviruses identified constituted novel species, and two others had not been previously reported in Venezuela. In addition, a novel deltasatellite (cabbage leaf curl deltasatellite, CabLCD) was found to be associated with cabbage leaf curl virus (CabLCV) in several plant species. CabLCD was the first deltasatellite found to infect legumes and the first found in the New World to infect a crop plant. Agroinoculation experiments using Nicotiana benthamiana plants and infectious viral clones confirmed that CabLCV acts as a helper virus for CabLCD. The begomovirus–deltasatellite complex described here is also present in wild legume plants, suggesting the possible role of these plants in the emergence and establishment of begomoviral diseases in the main legume crops in the region. Pathological knowledge of these begomovirus–deltasatellite complexes is fundamental to develop control methods to protect leguminous crops from the diseases they cause.

RETRACTED: Emergence of Asian endemic begomoviruses as a pandemic threat

“…They replicate by rolling circle amplification (RCA) using a double-stranded DNA (dsDNA) intermediate ( Yadava et al, 2010 ). Begomoviruses are classified into four categories based on their genomic structure and evolutionary relationships: New World (NW), Old World (OW), Sweepoviruses, and Legumoviruses ( Fiallo-Olivé et al, 2021 ). In OW and NW, pepper, tomato, and cucurbit plants are common hosts for begomoviruses ( Seal et al, 2006 ).…”

“…This has nonanucleotide sequence which is found in all geminiviruses, and it is their speciality ( Roshan et al, 2017 ). Begomoviruses in the OW can be both monopartite or bipartite and are associated with betasatellites, alphasatellites and deltasatellites ( Fiallo-Olivé et al, 2021 ). Alphasatellites, which are mostly found in monopartite OW begomoviruses, have a genome that encodes a replication-associated protein that is required for replication.…”

Begomoviruses: what is the secret(s) of their success?

“…In most cases, deltasatellites do not affect the symptoms caused by the helper begomoviruses [57][58][59][60][61]. However, it is not unusual that they influence accumulation of the helper virus.…”

Mixed infection of a new begomovirus, Jatropha leaf curl Guntur virus and recombinant/chimeric jatropha leaf curl Gujarat virus in Jatropha gossypiifolia

“…The association of deltasatellites extends to both monopartite Old World begomoviruses and bipartite New World begomoviruses reports suggest that deltasatellites can decrease or increase the amount of associated helper begomovirus in the host, but they rarely affect the symptoms caused by them (Fiallo‐Olivé and Navas‐Castillo 2020; Fiallo‐Olivé et al . 2021).…”