Red Seal Landscape Horticulturist Practice Exam

How does drought stress typically affect plant growth?

1. It encourages growth and flowering

2. It leads to wilting, reduced growth, and potential death of plants due to insufficient water

3. It improves root development

4. It enhances photosynthetic activity

The correct answer is: It leads to wilting, reduced growth, and potential death of plants due to insufficient water

Drought stress negatively impacts plant growth primarily because it creates a lack of sufficient water, which is crucial for several physiological processes within the plant. When plants experience drought stress, they often begin to wilt as they lose water faster than they can absorb it. This wilting occurs because the plant's tissues lose turgor pressure, which is necessary for maintaining structure and firmness. Additionally, insufficient water supply diminishes the plant's ability to perform photosynthesis, as water is a vital component in the photosynthetic process. The lack of water also affects nutrient uptake from the soil, leading to reduced growth. In extreme cases, prolonged drought stress can result in the death of the plant, as it is unable to sustain its metabolic functions without adequate water. This concept underscores the critical importance of water availability in promoting healthy plant growth and longevity.