What is referred to as a pathogen that can negatively affect crops?

The term that refers to a pathogen negatively affecting crops is virus or bacteria. Both viruses and bacteria are microorganisms that can cause various diseases in plants, leading to reduced growth, yield losses, and in severe cases, death of the plant.

Viruses can disrupt the normal functioning of plant cells, often resulting in symptoms such as stunted growth, discoloration, or deformation of leaves. Bacterial infections can cause wilting, rot, and other forms of tissue damage, often facilitating further disease spread in a crop.

While weeds and pests can also negatively impact crops, they are not classified as pathogens. Weeds compete with crops for nutrients, water, and light but are not disease-causing microorganisms. Pests refer to insects or animals that may harm crops physically but do not fit the classification of pathogens causing disease at the cellular level. Fungi can be considered pathogens as well; however, in this context, focusing on both viruses and bacteria as specific examples highlights a broader category of crop-damaging pathogens.

Therefore, the emphasis on virus or bacteria encompasses a key aspect of crop pathology, reinforcing the significance of these pathogens in the context of crop management practices.