Macroptilium yellow vein virus (Begomovirus macroptilivenae) associated with Macroptilium plants is geographically structured into divergent subpopulations
摘要
The genus Begomovirus (family Geminiviridae) includes plant viruses that have a negative impact on the production of several economically important crops worldwide. Begomoviruses infect a wide range of non-cultivated plants, which may serve as alternative hosts or inoculum sources for epidemics in crops. In this study, we evaluated the genetic variability and population structure of Macroptilium yellow vein virus (MacYVV; Begomovirus macroptilivenae), associated with non-cultivated Macroptilium spp. in the state of Alagoas (AL), northeastern Brazil. Complete DNA-A sequences (n = 29) were obtained from symptomatic plants collected in different municipalities of AL during 2019 and 2020. Pairwise sequence comparisons indicated a low degree of genetic variability, with 93.9–100% identity to 18 previously characterized sequences. To better understand the population structuring of MacYVV in AL, the complete DNA-A data set (n = 47) was analyzed. Although the DAPC and STRUCTURE approaches yielded slightly divergent numbers of putative MacYVV subpopulations, the results are consistent with the phylogenetic relationships among MacYVV isolates, where five well-supported subgroups correlated with geographic location were observed. The low variability of the MacYVV population could be related to the small number of recombination events detected and be reflective of a long-term virus-host relationship in which the virus is very well adapted to the host.