What type of plant disease do nutrient deficiencies and environmental extremes represent?

Nutrient deficiencies and environmental extremes fall under non-pathogenic diseases because they do not arise from infectious agents such as bacteria, viruses, or fungi. Instead, these issues emerge due to adverse growing conditions or lack of essential nutrients in the soil, affecting the plant's health and development. Non-pathogenic diseases typically result from physiological and environmental stressors, leading to symptoms like chlorosis, necrosis, or stunted growth without involving any pathogens. Understanding this distinction is crucial for effective horticultural management, as addressing nutrient deficiencies or modifying environmental conditions can often rectify these issues, unlike infectious diseases that require different control strategies.