Sequence analyses of Wheat dwarf virus isolates from different hosts reveal low genetic diversity within the wheat strain

Abstract

Wheat dwarf virus (WDV) causes disease in wheat ( Triticum aestivum ) and barley ( Hordeum vulgare ) in many parts of Europe. The host range also includes many species of the family Poaceae. WDV is only transmitted by the leafhopper Psammotettix alienus . During a five-year period (2001)(2002)(2003)(2004)(2005), grass samples were collected in central Sweden in the vicinity of fields with WDV-infected winter wheat. Screening with ELISA and PCR identified WDV in a low number of samples (8/1098) from only three grass species: Apera spica-venti , Avena fatua and Poa pratensis . In addition, triticale was found to be positive. Fourteen WDV isolates from Avena fatua , Apera spica-venti , Triticum aestivum , Lolium multiflorum , Poa pratensis , triticale and the insect vector Psammotettix alienus , were partially sequenced ( ca. 1200 nucleotides), providing the first published WDV sequences from the insect vector. All isolates belonged to the wheat strain of WDV and the genetic diversity was low. Phylogenetic analyses showed no clear grouping according to geographical location or host species. The results suggest that the same WDV genotypes are infecting both wheat and grasses in Sweden. Interestingly, one group of isolates (subtype B) formed a distinct clade in the phylogenetic tree. Subtype B was always found in mixed infection with the main genotype. Complete sequencing of a subtype B isolate showed that it was 98·6% identical to a typical wheat isolate from the same plant.

Discrimination and genetic diversity of Wheat dwarf virus in the Czech Republic

“…These isolates present a high degree of identity throughout the full genome. This low level of divergence confirms the previous report about the variability of the wheat strain of WDV, regardless of their host plants [27]. Although it has been proven that the LIR is the most variable genome segment of the wheat strain [13], our wheat isolates further underscore the low diversity in this region.…”

“…In conclusion, the results presented in this work have shown that the Czech isolates were divided into two distinct groups: wheat and barley strains. All three restriction profiles and sequence analyses confirm that the barley strain is restricted to the barley host, but the wheat strain seems to have multiple hosts [27], and our study having detected it in both wheat and barley plants.…”

Comparison of the potential rate of population increase of brown and green color morphs of Sitobion avenae (Homoptera: Aphididae) on barley infected and uninfected with Barley yellow dwarf virus

“…This aphid damages the host not only by feeding, but also by transmitting Barley yellow dwarf virus (BYDV) (Luteoviridae: Luteovirus), which is one of the most serious viral diseases of cereal crops worldwide (Stern, ; Fereres et al ., ; Jiménez‐Martínez et al ., ; Powell & Bale, ). In the last two decades, S. avenae has caused substantial economic losses by transmitting BYDV, which has reduced barley and wheat production in many countries, for example, Germany and China (Bishop & Sandvol, ; Huth, ; Wu et a1 ., ; Ramsell et al ., ).…”

Modification of Non-Vector Aphid Feeding Behavior on Virus-Infected Host Plant

“…The diseases caused by WDV and Barley yellow dwarf virus (BYDV), including CYDV, have been recognized as two of the most serious viral diseases of crops (Jiménez-Martínez et al 2004), threatening barley and wheat production and causing significant economic losses throughout the world (Bishop and Sandvol 1984; Huth 2000; Wu et al 2002; Ramsell et al 2008). …”