Bacterial ring rot is a highly destructive plant disease affecting potato crops, caused by the pathogen $Clavibactermichiganensis$.

Which of the following statements correctly describe how this pathogen is transmitted between potato plants or tubers?

1. Direct contact between infected and healthy potato tubers during storage.
2. Transfer of bacterial cells via contaminated agricultural machinery and harvesting equipment.
3. Dissemination of wind-blown endospores that infect healthy leaf foliage during dry weather.