In which geographic region is clubroot disease most commonly found?

Clubroot disease, caused by the pathogen Plasmodiophora brassicae, is predominantly found in temperate regions. This is because the conditions in temperate areas—such as moderate temperatures and adequate moisture—are ideal for the disease pathogen to thrive and spread. Clubroot primarily affects members of the Brassica family, including crops like cabbage, cauliflower, and broccoli.

In temperate climates, the soil conditions often support the survival of the pathogen in cyst form, allowing it to persist in the soil for several years, impacting crop rotation strategies. Moreover, the life cycle of the disease coincides with the growing seasons typical of temperate regions, when host plants are most susceptible.

In contrast, tropical regions usually experience a different set of climatic and soil conditions, making the development of clubroot less favorable. Desert and arctic regions present extreme environments—either overly arid or extremely cold—which do not support the pathogen's lifecycle or the growth of susceptible host plants. This distinction underscores why temperate zones are specifically associated with the prevalence of clubroot disease.