Chapter 31.3, Problem 2CC

Summary Introduction

To describe: The importance: Mycorrhizae in colonization of land.

Concept introduction: The term Mycorrhizae is derivative of Greek words "mukés", which means fungus, and "rhiza," which meaning roots. Mycorrhizal fungi first arrived on earth about 450 million years ago. Life on land before the evolution of plants has been labeled as "green slime”, because it was predominated by cyanobacteria, algae, various heterotrophic species, and fungi.

Mycorrhiza forms symbiotic relationships with roots of the plant. They form close association with the plant roots in order they can draw nutrients from the soil. This association between fungus and plant promotes plant growth. Similar associations might have been essential for the earliest land plants that did not have roots. Thus, beneficial relationships between plants and fungi existed from the early period and thus helped plants in colonization of land.