Agricultural concepts of roots: from morphogenetic to functional equilibrium between root and shoot growth.

Over the past century, emphasis has changed towards water and nutrient uptake by root system ('functional equilibrium') from relations between root and shoot growth, ('morphogenetic equilibrium'). Separate optima for root growth and shoot growth can often be distinguished. Relatively small root systems can suffice for maximum crop production, provided the supply of water and nutrients is plentiful. Deep tillage or water-table lowering, intended to increase rooting depth, can be counterproductive for plant growth. Larger root systems may, however, withstand rapidly changing environmental conditions better, and may increase nutrient use efficiency or reduce nutrient loss. (Abstract retrieved from CAB Abstracts by CABI’s permission)