MDARD Michigan Core Pesticide Applicator Practice Exam

What is defined as phytotoxicity?

1. Plant growth stimulation

2. Plant injury due to chemical exposure

3. Increased soil fertility

4. Soil erosion control

The correct answer is: Plant injury due to chemical exposure

Phytotoxicity refers specifically to plant injury or damage that results from exposure to certain chemicals, particularly pesticides or herbicides. This phenomenon occurs when the concentration of a chemical is high enough to harm plants, leading to symptoms such as leaf burn, stunted growth, or even death of the plant. Understanding phytotoxicity is crucial for pesticide applicators because it emphasizes the importance of proper application rates and techniques to prevent unintended harm to desirable plant species. The other options outline processes that are beneficial or unrelated to plant damage. Plant growth stimulation refers to enhancing plant growth through various means, such as fertilizers or specific growth regulators. Increased soil fertility pertains to the richness and availability of nutrients in the soil, which supports healthy plant growth. Soil erosion control involves practices that prevent the loss of soil, contributing to environmental health, but does not directly relate to the concept of plant injury. Thus, the emphasis on injury due to chemical exposure distinguishes phytotoxicity from these other agricultural concepts.