A New Tomato leaf curl virus from Mayotte

Area of Science:

• Plant Pathology
• Virology
• Molecular Biology

Background:

• Tomato plants in Mayotte exhibited stunting and leaf curl symptoms in 2003.
• The whitefly Bemisia tabaci, a known vector, was observed on affected plants.

Purpose of the Study:

• To identify the begomovirus associated with the observed tomato disease symptoms in Mayotte.
• To characterize the genetic makeup of the virus using molecular techniques.

Main Methods:

• Leaf samples from symptomatic tomato plants were collected from five regions of Mayotte.
• Polymerase chain reaction (PCR) assays were performed using degenerate primers targeting begomovirus DNA.
• PCR products were sequenced and analyzed for nucleotide identity to known begomoviruses.

Main Results:

• PCR assays successfully amplified begomovirus DNA from six symptomatic leaf samples.
• Sequence analysis revealed that the Mayotte isolates shared 80-83% nucleotide identity with Tomato yellow leaf curl virus (TYLCMV) and South African cassava mosaic virus (SACMV).
• Based on sequence identity thresholds (<90% in the coat protein gene core region), the virus represents a new begomovirus species.

Conclusions:

• The begomovirus identified in Mayotte represents a new species, provisionally named Tomato leaf curl Mayotte virus (ToLCMV).
• This finding contributes to understanding begomovirus diversity in the region and potential threats to tomato production.