Extension of practical solutions for efficient nitrogen management of vegetable crops: A comprehensive guide developed using a unique approach

Nitrogen (N) application often exceeds crop needs, particularly in vegetable production, in which the cost of lost yield far outweighs the cost of additional N fertilisation. Yet excessive N use may lead to negative health and environmental effects. While researchers and agronomists agree that many standard methods of making N recommendations do not adequately integrate the N-influencing characteristics of a given field, a comprehensive guide to sustainable N management in vegetable crops has been lacking. The need for such a guide was the impetus for this work, a collaboration between researchers in Quebec and Germany. The guide (Tremblay et al. 2001) demonstrates the use of the N balance approach in tailoring recommendations to crop needs. In so doing, it discusses the behaviour of N in the soil-plant-air system, methods for estimating and measuring the various N inputs and outputs, and the practical use of these in making efficient N recommendations on a per field basis. Also discussed are the environmental and health effects of excessive N fertilisation, and how these effects may be mitigated practically. A unique approach to the development of the guide involved its review by agronomists and researchers across the world to guarantee completeness. Its release as an electronic publication facilitates distribution and navigation within the text, and permits frequent updates that will ensure its continued relevance.