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Optimising interactions between N, P, and K supply. - HH3507SFV

Quality vegetable crops require a balanced supply of important plant nutrients, either from mineral fertilisers or organic nutrient sources. Use of unbalanced applications of major plant nutrients (particularly N, P and K) affects plant growth, encourages unacceptable nutrient accumulation in edible tissues, and may create unsightly nutrient disorders which reduce yields. They also waste fertiliser, and can lead to nutrient pollution from inefficient crop recoveries of one or more nutrients. Previous work to assess the N, P and K fertiliser requirements of a range of vegetable crops has focussed on predicting their responses to a single nutrient when the supply of the others is non-limiting, for example in RB209, the latest version of UK Fertiliser Recommendations. Mechanistic models of crop responses to individual nutrients have also been developed to determine the underlying principles, and some have been converted into simple decision support systems for providing advice on fertiliser applications. While these developments have been well received by both researchers and the industry alike, an important limitation to their wider exploitation is that their recommendations are restricted to individual nutrients. The aim of this project is to investigate the effects of interactions in the N, P and K supply on the yield and quality of vegetable and some arable crops (including potatoes) and to devise and validate a model to describe them. The results of the research will help to develop more sustainable strategies of nutrient use in conventional, low input and organic production systems, for example by providing advice on whether it would be more environmentally beneficial to raise the level of the most deficient nutrient to optimise production, or to adjust applications of other nutrients to achieve a better overall balance in supply. The model will be developed from the existing HRI models of N, P and K response respectively, and will incorporate new or improved routines from other models, where appropriate. These will be parameterised using data from the literature, although provision has also been made to carry out a limited number of field experiments to help parameterise the model, in addition to providing independent data for its validation. The final version of the model, which will be made available free of charge on the internet, will provide a single source of advice (a ‘one stop shop’) on NPK fertiliser use, providing the industry and their representatives with access to the latest research developments in this area, and encouraging wider take up of environmentally beneficial practices. Separate guidelines to growers for improving NPK use in vegetable production will also be produced.
01 Update individual N, P and K models to ensure that existing routines are fully inter-compatible, and carry out a preliminary parameterisation of the new soil and crop routines using existing data and information from the literature02 Develop and construct a model to describe the combined effects of the N, P and K supply on the response of a range of vegetable and some arable crops03 Design and conduct field experiments to parameterise the model and to validate key aspects of its performance using the results of sensitivity tests 04 Construct an internet version of the model and the associated programs for implementing it on a server05 Promote the results of the research to growers and consultants in the industry
Project Documents
• Annual Report : Optimising interactions between N, P and K supply   (433k)
Time-Scale and Cost
From: 2004

To: 2008

Cost: £567,768
Contractor / Funded Organisations
Warwick - HRI
Allocated - WHRI              
Climate Change              
Environmental Change              
Natural Resource Use              
Sustainable Farming and Food