Spatial distribution of two potyvirus in Puerto Rico

Viruses that affect crops have been intensively studied, but its unknown how these viruses affect non-cultivated plants. To develop the best strategies for crop protection, the diversity of viruses in non-cultivated plants needs to be understood. This work focuses on the occurrence of potyvirus in Momordica (Cucurbitaceae), an wild naturalized vine in Puerto Rico. We sampled 347 Momordica plants across Puerto Rico including adjacent islands of Culebra and Vieques. We used an enzyme-linked immunosorbent assay for detection of potyviruses and RT-PCR to amplify the CP region using MJ1 and MJ2 primers. Maps of both symptomatic and asymptomatic plants were developed using the species distribution model algorithm MaxEnt and screening of 20 environmental variables for the most informative layers inferring potential places of occurrence. The viruses PRSV and ZYMV were the most commonly encountered potyviruses. The presence of disease symptoms in Momordica was closely associated with the occurrence of PRSV and ZYMV. The distribution of PRSV, ZYMV and symptoms (found in Momordica) is clearly related to nearby cucurbit crop sites. Phylogenetic relationships among PRSV reported in 42 samples of Momordica were complex, yet no biogeographical signal was evident. This study provides insights into the interactions of virus with cultivated plants and non-cultivated plants and the impact of viruses introduced into natural environments should be further studied.