Type of disease caused by living organisms, multiply, and are transmitted from plant to plant?

• A. Noninfectious diseases
• B. Environmental stress
• C. Pesticide resistance
• D. Infectious diseases

Answer: (D)

Infectious diseases are caused by living organisms that multiply and can be transmitted from plant to plant. Pathogens like fungi, bacteria, viruses, and nematodes fit this description because they reproduce and spread to new hosts through water splash, wind-dispersed spores, contaminated tools, soil, or insect vectors. That contagious, multiplying, plant-to-plant spreading behavior is what sets infectious diseases apart. Noninfectious diseases come from nonliving factors such as nutrient deficiencies, chemical injuries, or environmental stress and don’t spread between plants. Pesticide resistance isn’t a disease type at all; it’s a pest’s adaptation to control measures.