Which of the following are NOT affected by mosaic virus?

Mosaic viruses are a group of viral pathogens that commonly affect a wide range of plants, particularly vegetables and ornamentals. When considering which plants are not typically affected by mosaic viruses, potatoes stand out as the correct choice.

Potatoes are known for being damaged by other types of plant viruses, but they are less commonly affected by the specific group of mosaic viruses compared to the other options listed. For instance, tomatoes, cucumbers, and soybeans are all susceptible to various strains of mosaic viruses, which can lead to distinct symptoms such as mottling and leaf distortion. Tomatoes are notably affected by the Tobacco Mosaic Virus (TMV), and cucumbers by Cucumber Mosaic Virus (CMV), both of which can severely impact plant health and yield.

Therefore, potatoes do not commonly exhibit issues due to mosaic viruses, making them the correct answer in this context. Understanding the specific viral interactions with different crops is key for effective management and mitigation strategies in agricultural practices.