Nutrient use efficiency in citrus

Abstract

Citrus production systems are inherently complex, which may hamper efficient resource management. This chapter aims to use a systems approach for structuring more efficient management options for citrus production. It starts by providing a brief overview of production trends in major production regions and outlining the use of a systems-based approach for structuring more sustainable management practices. Starting with the physiological processes and mechanisms controlling nutrient uptake of young seedlings, resource capture and utilization are presented including root growth dynamics and nutrient interception capacity as affected by diurnal crop water use, temperature, and nutrient supply. Uptake processes are scaled-up to a tree level and linked to specific environmental, crop development, and management aspects and integrated into generic conceptual models with special reference to the interactive effects of irrigation and fertility management as related to crop nutrient interception capacity. Then the scope is expanded to look at nutrient management at the field level on an annual basis including tree nutrient allocation, environmental emissions, and development of annual nutrient budgets. In the final section, future perspectives are provided for more effective use of modeling approaches for system design and more cost-effective and sustainable resource use.