ABSTRACT
The environmental conditions that prevail in the rhizosphere during plant growth will determine root growth and development. The environmental conditions that are linked to climate are precipitation, temperature, and solar radiation, which can modify root growth and development. Soil properties that determine the rhizosphere environment and can affect root growth are physical, chemical, and biological processes operating during plant growth. However, climatic and soil properties are interrelated in changing or de‰ning the rhizosphere environment. Hence, management strategies for improving root growth involve optimizing climatic variables like the availability of water, temperature, and solar radiation, and the physical, chemical, and biological properties of the soil. This strategy is known as the modi-‰cation of soil to ‰t the plants. The use of crop genotypes with higher yield potential and better root geometry is another strategy. This strategy is known as the modi-‰cation of plants to ‰t the soil. In addition, the root growth of crop plants can also be improved with the adoption of appropriate cultural practices. All these strategies involve soil and plant management and should be used together rather than in isolation to get best results in optimizing root systems. Nielsen (1974) reported that if conditions are favorable to growth, the root system should be structurally and morphologically able to use as much carbohydrates as the tops can supply and in turn supply as much water and nutrients as the tops can use. This chapter is meant to discuss soil, plant, and cultural practices that can be modi‰ed in favor of higher root system of crop plants.
