The greatest difference in health between two groups of plants of the same species, one group with mycorrhizae and one group without mycorrhizae, would be in an environment a. where nitrogen-fixing bacteria are abundant. b. that has soil with poor drainage. c. that has hot summers and cold winters. d. in which the soil is relatively deficient in mineral nutrients.

Verified step by step guidance

1. Identify the role of mycorrhizae: Mycorrhizae are symbiotic relationships between fungi and plant roots that help plants absorb more water and nutrients, especially phosphorus, from the soil.
2. Analyze the options: Consider each environment and how the presence or absence of mycorrhizae might impact plant health in those conditions.
3. Eliminate irrelevant options: Option a, where nitrogen-fixing bacteria are abundant, primarily affects nitrogen availability, which is not directly related to mycorrhizae function. Option b, poor drainage, primarily affects water logging tolerance, and option c, temperature extremes, is more related to climate adaptation rather than nutrient uptake.
4. Focus on nutrient availability: Mycorrhizae significantly impact nutrient uptake. In an environment where nutrients are scarce, plants without mycorrhizae would struggle more compared to those with mycorrhizae.
5. Choose the correct answer: The greatest difference in health between the two groups would be observed in option d, where the soil is relatively deficient in mineral nutrients, as mycorrhizae help in enhancing nutrient uptake from poor soils.

Key Concepts

Mycorrhizae

Mycorrhizae are symbiotic associations between fungi and plant roots that enhance nutrient uptake, particularly phosphorus, and improve water absorption. This relationship allows plants to thrive in nutrient-poor soils by extending their root systems and accessing resources that would otherwise be unavailable.

Nutrient Deficiency

Nutrient deficiency occurs when plants lack essential minerals required for growth, such as nitrogen, phosphorus, and potassium. In environments with low mineral availability, plants often struggle to perform vital functions, making the role of mycorrhizae crucial for improving nutrient acquisition and overall health.

Environmental Stressors

Environmental stressors, such as poor drainage or extreme temperatures, can significantly impact plant health. These conditions can exacerbate nutrient deficiencies and limit root function, making the presence of mycorrhizae even more beneficial as they help plants cope with these stresses by enhancing nutrient and water uptake.