Molecular characterization of genetic diversity of tomato (Solanum lycopersicum L.) begomovirus in Togo

摘要

Geminiviruses, in particular the members of the genus begomovirus, are considered to be a major phytosanitary problem for tomato crops production in the world. They are responsible for yield losses of up to 20 to 100% and Togo is not spared from this situation. The present study aimed to investigate the genetic diversity of the begomoviruses affecting tomato crops production in Togo and their relationship with other begomoviruses. To achieve these objectives, 307 samples of tomato leaves and wild plant species with typical virus symptoms were collected in the Maritime, Plateau, Central, Kara and Savannah regions and subjected to polymerase chain reaction (PCR) analysis. The results revealed the presence of begomovirus in 25.40% of the analyzed samples. The PCR products obtained were subjected to direct sequencing. Phylogenetic analysis of the sequences of the different regions of the DNA-A of the begomovirus identified in this study with that of other begomoviruses showed a nucleotide identity of 96% respectively to Tomato leaf curl Togo virus-Fontem, Tomato Leaf Curl Togo Virus, and Ageratum leaf curl Cameroon Alphasatellite; 98% respectively to Tomato leaf curl Nigeria virus, Ageratum leaf curl Cameroon virus, Tomato leaf curl Cameroon virus-Fontem, Ageratum leaf curl Cameroon virus and 99% respectively to Tomato leaf curl Kumasi virus, Pepper yellow vein Mali virus Bazegahot, and Pepper yellow vein Mali virus-Ouaga. These results suggest a high degree of genetic diversity of tomato begomoviruses identified in Togo.