ABSTRACT
Plant productivity is affected by many factors, some of which are associated with plant roots. Roots provide anchorage, synthesize certain essential hormones and amino acids, and absorb most of the water and mineral elements used in maintenance, growth, and reproduction of the plant. In some but not all situations, characteristics of the root system control productivity, especially when soil concentrations of available water or essential minerals are low. Roots also host symbiotic rhizobia and mycorrhiza, which often enhance plant growth. Conversely, factors that have adverse effects on top growth will have detrimental effects on root growth.
