Detection and identification of viruses in the Polish black locust (Robinia pseudoacacia L.) population

Black locust (Robinia pseudoacacia L.) is characterized by fast growth, low environmental requirements and aesthetic values and therefore it has become a very popular tree planted in forest and urban areas. In recent years, altered shape trees with virus-like symptoms on their leaves have been observed. Therefore, the aim of this work was to identify the virus species potentially causing visible symptoms. During the surveys carried out in 2016–2019, 683 black locust samples were collected. Out of 223 identified virus isolates peanut stunt virus (PSV) (58.7%) was predominant, followed by strawberry latent ringspot virus (SLRSV) (27.8%) and tomato black ring virus (TBRV) (13.5%). The occurrence of mixed infection was also recorded. Annual observation of infected trees confirms the negative impact of viruses on their growth and general condition, leading in many cases to dieback and felling of trees.