Virginia Commercial Pesticide Applicators CORE Exam

How do plant parasitic nematodes affect plants?

1. By improving nutrient uptake.

2. By interfering with water and nutrient absorption.

3. By promoting natural growth processes.

4. By spreading beneficial bacteria.

The correct answer is: By interfering with water and nutrient absorption.

Plant parasitic nematodes affect plants primarily by interfering with their ability to absorb water and nutrients. These microscopic roundworms invade plant roots and establish feeding sites, which can lead to physical damage of the root structure and dysfunction. The infestation results in reduced root mass and compromised root integrity, making it difficult for the plant to uptake essential nutrients and water from the soil. When nematodes feed on the roots, they disrupt the plant’s vascular system, which transports water and nutrients, consequently leading to symptoms such as stunted growth, wilting, and overall reduced vigor. This interference can also predispose plants to secondary infections by pathogens, compounding the negative effects on plant health. In contrast, the other options incorrectly imply beneficial roles of nematodes in plant growth or nutrient uptake, which does not align with the damaging nature of plant parasitic nematodes.