Occurrence and Geographical Distribution of Tospovirus Species Infecting Tomato Crops in Argentina

Abstract

“Peste negra” is a disease, caused by tospoviruses, that affects tomato crops in Argentina. Knowledge of the diversity, frequency, and distribution of different tospoviruses is essential for developing a rational control program based on genetic resistance sources. A study of the geographical distribution of tospoviruses affecting tomato crops in Argentina is presented in this paper. The areas surveyed were between the Tropic of Capricorn and 40°S and between longitude 58°W and 70°W. Tospovirus species were identified through double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA), using polyclonal antisera against Tomato spotted wilt virus (TSWV), Groundnut ringspot virus (GRSV), and Tomato chlorotic spot virus (TCSV). From tomato samples that reacted positively with any of the used antisera, 63% were GRSV, 28.2% were TCSV, and 8.8% were TSWV. A differential geographical distribution of tospoviruses was determined. Every plant that tested positive for GRSV was from central and northwest Argentina, while every plant TCSV-positive was from the northeast. TSWV was found only in the Río Negro Valley region in the south of the country. The wide dispersion of GRSV may be related to the spread of Frankliniella shultzei, which transmits this virus more efficiently than other vectors.

Transmission of Tomato spotted wilt virus by the dark form of Frankliniella schultzei (Thysanoptera: Thripidae) originating in tomato fields in Paraguay

“…F. schultzei adults originating in Brazilian populations efficiently transmit both TCSV (Wijkamp et al, 1995) and CSNV (Nagata and de Ávila, 2000), and the wide dispersion of GRSV in Argentina may also be attributed to F. schultzei (Williams et al, 2001). The findings reported in the present study strongly suggest that TSWV should also be added to the list of tospoviruses efficiently vectored by the dark form of F. schultzei in South America.…”

“…On the other hand, the pale form has been reported to be an inefficient vector of TSWV and TCSV and a non-vector of GRSV (Sakimura, 1969;Cho et al, 1988;Mau et al, 1991;Wijkamp et al 1995). The dark form is widespread throughout South America and is indicated as an important vector of tospoviruses in both Brazil (de Ávila et al, 1998) and Argentina (Williams et al, 2001).…”

Development of a locus-specific, co-dominant SCAR marker for assisted-selection of the Sw-5 (Tospovirus resistance) gene cluster in a wide range of tomato accessions

“…A number of related Tospovirus species (family Bunyaviridae) are responsible for the disease known as ''spotted wilt'', ''peste negra'' (Williams et al 2001), and ''vira-cabeça'' (Silberschmidt 1937), that causes severe annual yield losses of fresh-market and processing tomatoes (Solanum lycopersicum L.) around the world (Gordillo et al 2008). These viruses are transmitted by thrips (Thysanoptera: Thripidae) in a circulative-propagative manner (Wijkamp et al 1995).…”

“…Early infection of highly susceptible cultivars often leads to complete decay and death. Tomato spotted wilt virus (TSWV), Tomato chlorotic spot virus (TCSV), Groundnut ringspot virus (GRSV) and Chrysanthemum stem necrosis virus (CSNV) are the four prevalent Tospovirus species infecting tomatoes in tropical and sub-tropical areas of South America Giordano et al 2000;Williams et al 2001).…”

First report of Tomato chlorotic spot virus on Mirabilis jalapa

“…The isolate from P. peruviana clustered with Argentinean isolates, corroborating the findings of Eiras et al (2012). It is important to note that Rio Grande do Sul borders Argentina, possibly facilitating the spread of TCSV, and that the virus is highly prevalent in the border region between Brazil and Argentina (Williams et al 2001).…”