Optimizing Application of Phosphorus and Potassium to Processing Tomatoes under Drip Irrigation
IPNI-2007-CAN-ON28
25 May 2007
Impact/Benefits
Nutrient management has a major influence on crop, soil and water quality, especially the field vegetable crops which are highly nutrient-demanding and sensitive to application rate and timing, but very little research has been carried out. The requirement of high fertilizer rates vs. short growing season of field vegetable crops can make the efficiency of fertilizer use even lower than field crops. In the intensive vegetable production areas, such as southern Ontario, losses of nutrients (N and P) from soil-crop ecosystems is a major contributor to the deterioration of water quality. This issue can become more severe when supplemental irrigation is applied. Increasing efficiency of fertilizer use under optimum irrigation would reduce energy consumption in production, transport and application of fertilizer materials and improve economics of crop production, by reducing input costs and increasing yield. Increasing efficiency of fertilizer use will benefit the environment and long-term agricultural sustainability, since increased fertilizer use efficiency reduces the likelihood of excess P accumulation in the soil and P movement into fresh water. Fertilization can also influence crop quality and nutritional value, the important factors influencing the desirability and competitiveness of our crops in domestic and international markets.
Research is required to improve our ability to predict nutrient requirements of crops and synchronize nutrient supply with crop demand. Environmental benefits would include improved soil quality and soil ecological diversity, improved sustainability of agro-ecosystems, reduced risk of excess movement of nutrients (P &N) to surface water. Social benefits would include enhanced sustainability of rural economies, improved nutritional quality of food, and enhanced value of agricultural commodities entering both national and international markets. Information generated in this study supports the goals of APF, the development of water quality agri-environmental indicators (eg. phosphorus) in the NAHARP program, and the provincial nutrient Management Legislation.
The project is encompassed by the multiple-priorities of AAFC and approved studies, including OPs 120.3 (Safe and Efficient Use of Inorganic and Organic Fertilizer Products); 120.1 (Enhanced Understanding of Nutrient Cycling Processes in soil ); 120.5 (Beneficial (agricultural) Management Practices to Preserve / Improve Water Resources); and 120.4 (Impacts of Agriculture-Food Production Systems on Water Resources).