Plants under stress are more susceptible to pests; which outcome is most likely?

Plants under stress are more susceptible to pests; which outcome is most likely?

• A. Pest pressure remains stable
• B. Pest resistance increases
• C. Insects and disease susceptibility increases
• D. Pest populations disappear

Answer: (C)

When plants are under stress, their defense systems are weakened, so they’re easier targets for pests and diseases. Stress from drought, heat, cold, or nutrient shortage diverts energy from defense toward coping with the stress, leading to lower production of protective chemicals and weaker physical barriers. Defense signaling pathways can also become unbalanced, further reducing resistance. With defenses down, insects can feed more effectively and pathogens can invade more easily, so susceptibility increases. The idea that pest pressure would stay the same, pests would become more resistant, or pests would disappear doesn’t fit because stressed plants are generally harder to defend and more prone to damage.

When plants are under stress, their defense systems are weakened, so they’re easier targets for pests and diseases. Stress from drought, heat, cold, or nutrient shortage diverts energy from defense toward coping with the stress, leading to lower production of protective chemicals and weaker physical barriers. Defense signaling pathways can also become unbalanced, further reducing resistance. With defenses down, insects can feed more effectively and pathogens can invade more easily, so susceptibility increases. The idea that pest pressure would stay the same, pests would become more resistant, or pests would disappear doesn’t fit because stressed plants are generally harder to defend and more prone to damage.