Incidence and Distribution of Iris yellow spot virus on Onion in Serbia

Abstract

In a survey to determine the presence and distribution of Iris yellow spot virus (IYSV) in greenhouse ornamentals and onion field crops in 14 districts of Serbia as well as on imported ornamental plants, 1,574 samples were collected and analyzed by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). IYSV was not detected in nearly 1,200 plant samples collected from 39 genera of ornamentals grown in greenhouses in Serbia or imported from other countries during 2005 to 2007. The virus was detected in samples from an onion seed crop in the Sirig locality (South Bačka District) that showed symptoms resembling those caused by IYSV and in samples without IYSV-like symptoms from an onion bulb crop in the Obrenovac locality (City of Belgrade District). Mechanical transmission of IYSV isolates was difficult, and only the isolate 605-SRB could infect four plant species, but not in all replications. No virus transmission could be demonstrated in 5,000 tested seeds originating from IYSV-infected onion crops. For further confirmation of IYSV, the nucleotide sequence of its nucleocapsid (NC) gene was obtained by reverse transcription–polymerase chain reaction (RT-PCR) in symptomatic onion samples as well as in symptomless leaves of Nicotiana benthamiana. Four previously developed primers were tested to determine their suitability for routine detection of Serbian IYSV isolates. Phylogenetic analysis showed clustering of isolates 605-SRB and 622-SRB from the onion seed crop and isolate 283-SRB from the onion bulb crop into two distant clades. The analysis indicated that Serbian isolates of IYSV do not share a recent common ancestor and that they represent two distinct lineages of IYSV in Serbia. Considering that onion is one of the most important and traditionally grown vegetable crops in Serbia, IYSV represents a potentially devastating pathogen in this country.

Molecular epidemiology of Impatiens necrotic spot virus on greenhouse ornamental plants in a local area of Japan

“…Genetic relationships between the virus isolates have been investigated in tospoviruses such as TSWV (Bhat et al 1999;Heinze et al 2001;Lee et al 2011;Pappu et al 1998;Sivparsad and Gubba 2008;Tentchev et al 2011;Tsompana et al 2005) and iris yellow spot virus (IYSV) (Bulajić et al 2009;Nischwitz et al 2007;Pappu et al 2006;Smith et al 2006) but not in INSV. Members of the genus Tospovirus are characterized by an RNA genome composed of three RNA segments: small (S), middle (M), and large (L).…”

Evaluation of Seed Transmissibility of Soybean Vein Necrosis-Associated Virus in Two Soybean Cultivars Grown Under Field Conditions

“…Hence, late growth stage infection of soybean with SVNaV, where pods are already formed, further reduces the chance of SVNaV for being seed transmissible. One should also take into account the lack of evidence for seed transmissibility of all known tospoviruses in general [39][40][41][42]. Interestingly, TSWV is detectable in pod shells and seed testa of infected peanut; however, sowing such seeds did not result in virus transmission [28,43].…”

Detección de Iris yellow spot virus en cebolla cultivada en Tepalcingo, Morelos, México

“…Its presence has been detected since 1981 in Brazil and the United States (Cortês et al, 1998.). IYSV has exteded to important onion-producing regions worldwide (Bulajić et al, 2009;Córdoba et al, 2005;Du Toit et al, 2004;Gent et al, 2006;Gera et al, 2004;Nischwitz et al, 2007;Pozzer et al, 1999;Schwartz et al, 2002;Smith et al, 2006).…”