Diseases in plants are caused by biological agents known as what?

Diseases in plants are primarily caused by biological agents known as pathogens. Pathogens include a wide range of microorganisms, such as fungi, bacteria, viruses, and nematodes, that can infect and cause diseases in plants. These organisms invade plant tissues, leading to various symptoms like wilting, chlorosis, lesions, and in severe cases, plant death.

Understanding pathogens and their role in plant diseases is crucial for effective disease management and control strategies. By identifying the specific type of pathogen involved, one can implement appropriate measures to prevent or mitigate the spread of the disease, such as improving plant health, rotating crops, or applying fungicides and bactericides when necessary.

In contrast, while insects and pests may contribute to plant health issues, they do not directly cause the diseases associated with pathogens. Similarly, parasites, although they can affect plants, are not the primary biological agents responsible for plant diseases in the same context as pathogens. Therefore, recognizing pathogens as the correct answer emphasizes their critical role in the biological processes that lead to plant disease.