First report of Phasey bean mild yellows virus in Kenya with a new host record

Abstract

Genome studies in Australia reported a novel virus, Phasey bean mild yellows virus (genus Polerovirus; PBMYV), in mixed infections with Bean leaf roll virus, Faba bean polerovirus 1, Soybean dwarf virus and Turnip yellows virus naturally infecting phasey bean (Macroptilium lathyroides) (Sharman et al., 2021). Transmission studies with Aphis craccivora and by grafting with infected scions identified fabaceous hosts including chickpea, faba bean and pea as additional hosts of PBMYV (Wilson et al., 2012). In general, poleroviruses have narrow host ranges restricted to members of one or a few plant families, although exceptions exist (King et al., 2012). Sharman et al. (2021) found PBMYV in one non-legume host (Anagallis arvensis) suggesting that hosts outside the Fabaceae may be found. Previous field surveys in Kenya on leguminous crops observed mild yellowing symptoms and PBMYV was detected in pooled samples from these plants (Mukoye et al., 2020).