A crop problem is a type of agricultural issue that can arise from a variety of causes, such as pests, diseases, or environmental factors. Three common crop problems are ROT, SMUT, and ERGOT. ROT is a type of decay caused by fungi or bacteria that can affect the quality of crops. SMUT is a type of fungal disease that can cause discoloration and deformity in plants. ERGOT is a type of fungus that can cause grain to become toxic and can lead to serious health issues if consumed.