Weed Hosts Represent an Important Reservoir of Turnip Yellows Virus and a Possible Source of Virus Introduction into Oilseed Rape Crop

Abstract

Turnip yellows virus (TuYV) is one of the most important pathogens of oilseed rape worldwide. The virus has a large host range including many crop species (e.g., oilseed rape, pea, chickpea) and weeds from more than twenty plant families. Other than oilseed rape, we detected TuYV in many commonly grown weed species that share the fields and vegetation period together with canola crops in Czech and Slovak Republics. TuYV was detected by reverse-transcription polymerase chain reaction (RT-PCR) in at least 26 species including main crop hosts (oilseed rape), intercrops and weeds such as Amaranthus retroflexus, Atriplex patula (Amaranthaceae), Arctium lappa, Lactuca serriola, Taraxacum officinale, Tripleurospermum inodorum (Asteraceae), Phacelia tanacetifolia (Boraginaceae), Brassica napus, Capsella bursa–pastoris, Descurainia Sophia, Raphanus raphanistrum, Sinapis alba, Sisymbrium officinale, Thlaspi arvense (Brassicaceae), Silene alba, Stellaria media (Caryophyllaceae), Euphorbia helioscopia (Euphorbiaceae), Geranium rotundifolium (Geraniaceae), Lamium purpureum (Lamiaceae), Fumaria officinalis, Papaver rhoeas (Papaveraceae), Veronica persica (Plantaginaceae syn. Scrophulariaceae), Fallopia convolvulus (Polygonaceae), Solanum nigrum (Solanaceae), Urtica dioica (Urticaceae) and Viola arvensis (Violaceae). The detection of TuYV was further confirmed by RT-qPCR as well as Sanger sequencing of the PCR fragments. We discovered four new weed species as hosts of TuYV such as T. inodorum, S. alba, G. rotundifolium and E. helioscopia, representing their three respective plant families. The readthrough domain (RTD) gene sequence analysis of the Czech and Slovak TuYV isolates from oilseed rape and weed species showed similar within-group nucleotide divergence (7.1% and 5.6%, respectively) and the absence of geographical- or host-based phylogenetic clustering. The high-throughput sequencing of the P. rhoeas sample enabled the obtention of a nearly complete genome of TuYV and revealed the mixed infection of TuYV with turnip mosaic virus and cucumber mosaic virus. Our results thus show that weed species are an important TuYV reservoir and play a significant role in the spread and incidence of the disease in field crops such as oilseed rape.

¿Malezas o arvenses? Una propuesta conceptual para su manejo agroecológico

“…Algo similar ocurre con varios patógenos importantes. Una razón para controlar una maleza, aunque se encuentre sólo en el borde del área agrícola, es evitar la multiplicación de plagas y enfermedades que luego afectarán al cultivo (Slavíková et al, 2022).…”

Evaluation of Resistance of Oilseed Rape Genotypes to Turnip Yellows Virus

“…Three individual experiments were conducted to observe the resistance of oilseed rape genotypes associated with TuYV infection based on virus titres (virus copy number) determined 4 weeks after infection using RT-qPCR [11]. The one-way ANOVA revealed a statistically significant difference (F (22, 149) = 16.64), (p < 0.0001) in the mean TuYV titre levels between the genotypes.…”

“…One of the most devastating and economically important viral diseases in oilseed rape is turnip yellows virus (TuYV) [4,5]. TuYV belongs to the genus Polerovirus in the family Solemoviridae [6] and infects a wide host range, including economically important crops, intercrops, weeds and pasture hosts [7][8][9][10][11]. TuYV causes yellowing, dwarfing, leaf redness, interveinal chlorosis and stunted growth, which can lead to significant yield losses of 11 to 46% in all major oilseed rape growing regions of the world [12][13][14][15][16][17].…”

“…Our results provide information on the level of resistance of commercially available varieties, as well as of newly developed breeding lines of oilseed rape, and therefore may contribute to reducing the yield losses caused by the virus infection and finding new sources of resistance for crop improvement. Three individual experiments were conducted to observe the resistance of oilseed rape genotypes associated with TuYV infection based on virus titres (virus copy number) determined 4 weeks after infection using RT-qPCR [11]. The one-way ANOVA revealed a statistically significant difference (F (22, 149) = 16.64), (p < 0.0001) in the mean TuYV titre levels between the genotypes.…”

Turnip Yellows Virus Field Infection in Oilseed Rape: Does It Impact the Yield and Quality?

“…The TuYV has a wide host range, including many crop species (e.g., OSR, Indian mustard, cauliflower, and many other species of Brassica) and weeds from more than twenty plant families (e.g., Amaranthaceae (Amaranthus retroflexus), Asteraceae (Taraxacum officinale), Brassicaceae (Brassica napus, Capsella bursa-pastoris, Descurainia sophia, Raphanus raphanistrum, Sinapis alba)) [15,16]. TuYV was detected in the pod components of OSR seeds (ELISA test), as it was present in the pod wall, septum, and seed coat; however, it was present in only 2 out of 78 embryos [15,17].…”