| Scientific Name | Bremia sonchicola (Schltdl.) Sawada, Descript. Cat. Formosa Fungi: 47 (1927) |
|---|---|
| Synonyms | 2 synonyms= Botrytis sonchicola Schltdl., Bot. Zeitung (Berlin) 10: 620 (1852)
= Bremia lactucae f. sonchicola (Schltdl.) L. Ling & M.C. Tai, Trans. Brit. Mycol. Soc. 28: 24 (1945) |
| Disease | Downy mildew |
| Taxonomic Rank | |||
|---|---|---|---|
| Order | Peronosporales | Family | Peronosporaceae |
| Host Plant | |||
|---|---|---|---|
| Common Name | Prickly Sowthistle (큰방가지똥) | Scientific Name | Sonchus asper |
| Common Name | Common Sow-Thistle (방가지똥) | Scientific Name | Sonchus oleraceus |
| Distribution | Brazil, China, Germany, Greece, Korea, Spain, Taiwan, Ukraine |
|---|---|
| Characteristics | Lesions commonly present on leaves, initially pale green to yellow, later becoming brown to greyish. Down present on leaves, consisting of conidiophore outgrowth forming patches. Conidiophores (270–)301–412–523(–670) μm long, with the trunk 9–12 μm wide below the first branch, dichotomously branched, and with the first branch arising at 2/10–5/10 of the total conidiophore length. Branching occurs in 5–6(–7) orders. Callose plugs are rarely present in the trunk but common in the branches. Ultimate branchlets are slightly curved to substraight and 8–25 μm long. Vesicles (n = 50) are spherical, 9–13 μm in diameter, and bear 4–6 extensions, each 4–10 μm long; the tips of the extensions are mostly swollen but rarely obtuse and 2–3 μm wide. Conidia (n = 30) are subglobose to globose, rarely ovoid, subhyaline, (14.6–)16.6–18.8–21.0(–22.1) × (13.7–)15.7–17.9–20.1(–21.1) μm, with a length/width ratio of (0.94–)0.99–1.05–1.11(–1.18); the pedicel is absent or, rarely, short and conical. |
| Notes | Bremia sonchicola is a host-specialized downy mildew associated mainly with Sonchus spp. Although historically included in the broad concept of B. lactucae, morphological and multilocus phylogenetic analyses supported its recognition as a distinct species (Choi et al., 2011). Multigene analyses revealed closely related lineages from geographically distant populations and supported strong host-associated diversification within Bremia (Choi and Thines, 2015). Molecularly confirmed records from Germany, Greece, Spain, Korea, and, most recently, Brazil indicate that B. sonchicola is widely distributed on Sonchus, particularly S. oleraceus. The Brazilian record represents the first molecularly confirmed occurrence of the species in South America (de Moraes et al., 2026). |
| Economic importance | Sonchus spp. are primarily wild or weedy plants, and B. sonchicola is therefore of limited direct economic importance. No substantial crop losses caused by this species have been documented. |
| References | Choi, Y. J., et al. 2011. Fungal Biol. 115:102. Choi, Y. J., and Thines, M. 2015. PLoS ONE 10:e0133655. de Moraes, G. S., et al. 2026. Mycol. Prog. 25:56. |
