First Report of Tomato yellow leaf curl virus in Hawaii

Abstract

Tomato yellow leaf curl disease, caused by the begomovirus Tomato yellow leaf curl virus (TYLCV; family Geminiviridae), is an economically important disease of tomato (Solanum lycopersicum L.) that can be very destructive in tropical and subtropical regions (1). In October 2009, tomato plants showing stunted new growth, interveinal chlorosis, and upward curling of leaf margins were reported by a residential gardener in Wailuku, on the island of Maui. Similar symptoms were observed in approximately 200 tomato plants at a University of Hawaii research farm in Poamoho, on the island of Oahu in November 2009. The similarity between these symptoms and those of tomato yellow leaf curl disease and the presence of whiteflies (Bemisia spp.), the vector of TYLCV, suggested the causal agent was a geminivirus such as TYLCV. Total nucleic acids were extracted from a tomato plant sample from Wailuku and Poamoho and used in a PCR assay with degenerate primers PAR1c715 and PAL1v1978 for geminivirus detection (4). The ~1.5-kbp amplicon expected to be produced from a geminivirus template was generated from the symptomatic tomato plant samples but not from a greenhouse-grown control tomato plant. The amplicons were cloned by the pGEM-T Easy vector (Promega, Madison, WI). Three clones from each sample were sequenced, revealing 97 to 99% nucleotide identity to TYLCV sequences in GenBank and a 98.9% nucleotide identity between the Wailuku (Accession No. GU322424) and Poamoho (Accession No. GU322423) isolates. A multiplex PCR assay for the detection and discrimination between the IL and Mld clades of TYLCV was also performed on these isolates (2). A ~0.8-kbp amplicon was generated from both isolates confirming the presence of TYLCV and their inclusion into the TYLCV-IL clade (2). Seven symptomatic and three asymptomatic tomato plant samples from Poamoho were tested for TYLCV using a squash-blot hybridization assay (3) utilizing a digoxigenin-labeled probe derived from the ~1.5-kbp PCR amplicon. All symptomatic tomato plants and one asymptomatic tomato plant were found to be infected with TYLCV. How the virus entered Hawaii and how long it has been present is unknown. The most plausible route is through infected plant material such as an asymptomatic alternative host rather than viruliferous whiteflies. It appears TYLCV is not a recent introduction into Hawaii since the Wailuku gardener observed similar disease symptoms for a few years before submitting samples for testing. In January 2010, TYLCV was also detected in two commercial tomato farms on Oahu, posing a serious threat to the state's $10 million annual tomato crop. References: (1) H. Czosnek and H. Laterrot. Arch. Virol. 142:1392, 1997. (2) P. Lefeuvre et al. J. Virol. Methods 144:165, 2007. (3) N. Navot et al. Phytopathology 79:562, 1989. (4) M. R. Rojas et al. Plant Dis. 77:340, 1993.

Ongoing geographical spread of Tomato yellow leaf curl virus

“…We also detected two movements of TYLCV-IL from East Asia to the North American region (but also possibly directly to Hawaii), between 2006 and 2009 and between 2000 and 2010, which is consistent with the first reports of TYLCV-IL in Hawaii in 2009 (Melzer et al, 2010). An additional movement from East Asia, which further underlines the importance of this region as a major hub of global TYLCV dissemination, was to the Caribbean between 2006 and 2011.…”

“…We also inferred one movement of a Brisbane group TYLCV-IL virus from Australia to East Asia between 2000 and 2011 (most likely to Japan) and another to the USA (to either Hawaii or California) (Melzer et al, 2010;Rojas and Kon, 2007) between 2004. These movements coincided with outbreaks of TYLCV in Arizona and Texas (Isakeit et al, 2007), which were previously thought to have an independent, possibly EastAsian, origin to the TYLCV-IL variants found in the Caribbean (Duffy and Holmes, 2008;Lefeuvre et al, 2010).…”

Evolutionary and Molecular Aspects of Indian Tomato Leaf Curl Virus Coat Protein

“…Whiteflies harboring virus can nonspecifically infect a wide spectrum of plant crops and weeds including eggplant, potato, tobacco, pepper, and common bean. Infected plants seem healthy but develop symptoms leading to enormous economic loss [2]. …”

Gene-Based Markers for the Tomato Yellow Leaf Curl Virus Resistance GeneTy-3

“…Tomato yellow leaf curl virus (TYLCV) disease transmitted by the whitefly (Bemisia tabaci) is one of the most devastating diseases causing quality and yield reduction in tomato (Liu et al 2013). According to recent reports, TYLCV disease is spreading due to global warming, with current outbreaks in the United States and China (Rojas et al 2007;Zhang et al 2009;Melzer et al 2010). Recently, TYLCV incidence was also reported in Korea (Lee et al 2010).…”