Whiteflies pose a major threat to crops worldwide, primarily because they transmit begomoviruses with which they have evolved intricate mutualistic...

Begomoviruses are some of the most damaging threats to tomato crops globally. To fight these viruses, scientists breed specific protective genes, known as Ty-genes, into tomato plants. However, relyin...

Tomato yellow leaf curl disease is a major viral disease severely affecting tomato crops in the Mediterranean region, leading to reduced crop yield and significant economic losses. The disease is caused by monopartite begomoviruses belonging to the Geminiviridae family, primarily tomato yellow leaf curl Sardinia virus (TYLCSV) and tomato yellow leaf curl virus (TYLCV), which often co-infect tomato plants, promoting the emergence of recombinant viral genomes. To investigate the diversity and evolutionary dynamics of these viruses, symptomatic plants collected from agricultural sites in Sicily between 2020 and 2022, along with archived plant samples from 1994 to 1999, were analysed. For each collection site, leaves from symptomatic plants were pooled to form representative samples. Total nucleic acids were extracted and subjected to rolling circle amplification to enrich circular viral genomes. The amplified products were sequenced using Oxford Nanopore Technologies (ONT) long-read sequencing to obtain full-length viral genomes. Bioinformatic analyses revealed that archived samples mainly contained TYLCSV-related sequences, confirming its historical predominance in Sicilian agroecosystems. Recent samples, by contrast, were dominated by TYLCV-derived recombinants such as TYLCV-IS141- and TYLCV-IS76-like variants, indicating a temporal shift in the structure of the viral population. Furthermore, a distinct group of newly emerged recombinants, provisionally referred to as TYLCV-IMS54, was identified in the most recent samples. Their genome comprises a TYLCV backbone, a 54-nt segment from TYLCSV located downstream of the stem-loop region and a 341-nt region derived from TYLCV-Mild. These results demonstrate the importance of continuous viral population monitoring through ONT-based sequencing to detect emerging variants that may influence disease management strategies in tomato crops and highlight the central role of recombination in shaping begomovirus populations.

Begomoviruses are globally distributed plant pathogens that significantly limit crop production. The

RNA-dependent RNA polymerases (RDRs) are key players in the antiviral defence mediated by RNA silencing in plants. RDR6 is one of the major components of the process, regulating the infection of certa...

The research team tested tomato plants against three begomoviruses that differed in virulence.

Tomato yellow leaf curl disease (TYLCD) was reported in western Mediterranean basin since the late 1

In recent years, cassava, a staple food crop in many parts of Africa, has been subject to increasing challenges posed by a myriad of diseases. Among these, cassava mosaic disease (CMD) stands out due to its significant impact on agricultural output and food security in regions such as Burkina Faso. The disease, caused by a group of viruses known collectively as cassava mosaic begomoviruses, has escalated in incidence and severity, leading researchers to delve deep into its epidemiology and management strategies.

The Abutilon mosaic virus (AbMV) encodes a nuclear shuttle protein (NSP), and a movement protein (MP) which cooperatively accomplish viral DNA transpo…

Even with today's advanced agricultural technologies, plant diseases can still be extremely devastating to crops, causing billions of dollars in losses worldwide every year. Begomoviruses represent a…

Tomato yellow leaf curl disease (TYLCD) was reported in western Mediterranean basin since the late 1

Begomoviruses are globally distributed plant pathogens that significantly limit crop production. The

Granier, Martine1, 2 ; Faize, Mohamed3 ; Passera, Sandie4; Urbino, Cica1, 2 ; Peterschmitt, Michel1, 2 1 CIRAD, UMR PHIM, F-34398 Montpellier, France 2 PHIM, Univ Montpellier, CIRAD, INRAE, Institut…