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Tobacco curly shoot virus (TbCSV), a begomovirus, causes significant economic losses in tobacco and tomato crops across East, Southeast, and South Asia. Despite its agricultural importance, the evolutionary dynamics and emergence process of TbCSV remain poorly understood. This study analyzed the phylodynamics of TbCSV by examining its nucleotide sequences of the coat protein (CP) gene collected between 2000 and 2022. Using various combinations of priors, Bayes factor comparisons identified heterochronous datasets (3 × 100 million chains) generated from a strict molecular clock and Bayesian skyline tree priors as the most robust. The mean substitution rate of the CP gene was estimated at 6.50 × 10−4 substitutions/site/year (95% credibility interval: 4.74 × 10−4–8.50 × 10−4). TbCSV was inferred to have diverged around 1920 CE (95% credibility interval: 1887–1952), with its most probable origin in South Asia. These findings provide valuable insights for the phylogeography and evolutionary dynamics of TbCSV, and contribute to a broader understanding of begomovirus epidemiology.

Rice stripe virus (RSV) is one of the most important viral pathogens of rice in East Asia. The origin and dispersal of RSV remain poorly understood, but an emerging hypothesis suggests that: (i) RSV originates from Yunnan, a southwest province of China; and (ii) some places of eastern China have acted as a center for the international dissemination of RSV. This hypothesis, however, has never been tested rigorously. Using a data set comprising more than 200 time-stamped coat protein gene sequences of RSV from Japan, China and South Korea, we reconstructed the phylogeographic history of RSV with Bayesian phylogeographic inference. Unexpectedly, the results did not support the abovementioned hypothesis. Instead, they suggested that RSV originates from Japan and Japan has been the major center for the dissemination of RSV in the past decades. Based on these data and the temporal dynamics of RSV reported recently by another group, we proposed a new hypothesis to explain the origin and dispersal of RSV. This new hypothesis may be valuable for further studies aiming to clarify the epidemiology of RSV. It may also be useful in designing management strategies against this devastating virus.

Cherry leaf roll virus (CLRV) is an important plant pathogen that causes severe and detrimental effects on cherry and other fruit plants. Despite recent progress in plant pathology, molecular biology, and population genetics of CLRV, the spatiotemporal spread of this virus remains poorly studied. In this study, we employed a Bayesian phylodynamics framework to investigate the spatial diffusion patterns of CLRV by analyzing the coat protein gene sequences of 81 viral isolates collected from five different countries. Consistent with the trade of cherry, our Bayesian phylodynamic analyses pointed to viral origins in New Zealand and identified multiple migration pathways between Germany and other countries, suggesting that Germany has played an important role in CLRV transmission. The results of our study will be useful in developing sustainable management strategies to control this pathogen.