The tomato ‘marchitez’ disease in Mexico is caused by a new virus
In Mexico, tomato growers in Sinaloa, Sonora and Baja California recently observed the emergence of a new disease which was called ‘marchitez’ or ‘marchitez manchada’. Symptoms commonly include necrotic growing apices, elongated necrotic lesions on stems, and less commonly, ringspots on green fruits. Initially, the disease was thought to be caused by a new strain of Tomato spotted wilt virus (Tospovirus) but studies revealed the presence of a new virus. A virus with small isometric particles was isolated and characterized from tomato samples showing severe symptoms of ‘marchitez’ and collected from the Culiacan area (Sinaloa state). In the Culiacan area, this new virus was found to be widely distributed in symptomatic tomato plants. Whiteflies and aphids were present throughout the season when samples were collected but their involvement in ‘marchitez’ epidemics is not known. Molecular studies showed that this new virus showed greatest similarity with members of the Sequiviridae family and was tentatively called Tomato apex necrosis virus (Turina et al., 2007).
Almost simultaneously, another team of researchers isolated a new virus with small isometric particles from tomato plants affected by ‘marchitez’ in the state of Sinaloa, Mexico. This new virus was found related to, but distinct from, Tomato torrado virus and was tentatively called Tomato marchitez virus. It is also proposed that it should be assigned to a new plant virus genus called Torradovirus (Verbeek et al., 2008).
Sources
Turina M, Ricker MD, Lenzi R, Masenga V, Ciuffo M (2007) A severe disease of tomato in the Culiacan area (Sinaloa, Mexico) is caused by a new picorna-like viral species. Plant Disease 91(8), 932-941.
Verbeek M, Dullemans AM, van den Heuvel JFJM, Maris PC, van der Vlugt RAA (2008) Tomato marchitez virus, a new plant picorna-like virus from tomato related to tomato torrado virus. Archives of Virology 153(1), 127-134 (abst.).