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Partial root drying: delivering water saving and sustainable high quality yield into horticulture - HH3609TX

Approximately 70% of world-wide water use is committed to agriculture. Despite this, water shortages limit food production in many regions and if crop production is to be sustained and even increased in a changing environment then water must be used more efficiently. This is certainly the case in the UK where irrigation is required in most regions in most years to ensure reasonable crop yields of the required quality. The predicted impact of climate change on UK weather patterns will increase this reliance on irrigation and is focussing attention on irrigation techniques that allow more efficient use of water. Increasingly, higher value horticultural crops are grown in the UK under protected cropping. This increases yield quality but also provides opportunities both to save water and nutrient resources and to use modified supplies of these variables as regulators of growth and development. This type of ¡¥natural¡¦ growth regulation can replace the widespread use of growth regulating chemicals, an expensive and undesirable component of crop production. Deficit- or nutrient-induced growth regulation can also reduce labour costs for the industry. These highlighted features are all consistent with DEFRA policy for sustainable use of natural resources and labour (Horticultural Crop Sciences ROAME A HH36).
Partial Rootzone Drying (PRD) is a novel deficit irrigation technique which is designed to enhance water use efficiency in crop production by exploiting the plant¡¦s long-distance signalling mechanisms that modify plant growth, development and functioning as the soil dries. The novel science behind these mechanisms has been revealed in the last 15 years or so, largely by the members of this consortium. Exploitation of the science has been actively pursued in two projects in particular, namely the wine grape project centred on the South Australian wine industry based in Adelaide and an EU PRD consortium (IRRISPLIT) co-ordinated in Lancaster. PRD has delivered substantial water savings into the agricultural systems investigated by these projects (and increasingly into other agricultural systems around the world) and has also resulted in significant added value in terms of increased yield quality, labour saving and crop scheduling.
The main objective of this project is to deliver substantial saving of irrigation water in different sectors of UK Horticulture while maintaining or improving crop quality. This will be achieved through optimising the use of PRD technology. While many PRD trials have delivered very positive results, this is not always the case and we seek to understand why this happens. More information is needed on the basic science of long distance signalling and the interactive effects of variable climate and rooting medium with signalling. We will also address the mechanisms that contribute to changes in yield quality under PRD.
By the end of this project we will have:
„h Demonstrated potential water savings under deficit irrigation in a range of horticultural cropping systems.
„h Quantified the effects of PRD and deficit irrigation on yield, WUE and crop quality.
„h Identified the long distance signals that underlie the plant responses to PRD.
„h Established the environmental conditions that maximise the benefits of PRD.
„h Determined the optimum scheduling for implementation of deficit irrigation.
„h Transferred the results of the project to the horticultural industry in the form a decision support tool allowing application of PRD across a range of horticultural sectors
„h Developed a LINK consortium to facilitate further implementation within the horticultural industry

This consortium is uniquely placed to aid DEFRA in its perception and vision of future needs for horticulture and the environment. Expertise of different partners is varied but complementary and together we are able to offer an un-rivalled array of capabilities which, for reasons explained below, will be necessary for the successful completion of this project.
1. To quantify potential water saving under deficit irrigation and the impact of these treatments on yield and WUE (Lancaster, HRI and Dundee)
2. To determine and quantify signalling mechanisms under deficit irrigation (HRI as lead partner)
3. To determine the effects of PRD on resource partitioning and root and leaf functioning (Lancaster as lead partner)
4. To determine the environmental conditions and substrates that maximise the benefits of PRD (Dundee as lead partner)
5. To determine the optimal scheduling of deficit irrigation in the field (Dundee as lead partner)
6. To determine the 'quality' of deficit-grown produce. (HRI as lead partner)
7. To ensure effective technology transfer (Lancaster, HRI and Dundee)
Project Documents
• Final Report : Partial rootzone drying: delivering water saving and sustained high quality yield into horticulture   (1528k)
• Abstract : Partial rootzone drying: delivering water saving and sustained high quality yield into horticulture   (1528k)
• ANX - Annex : App1-TT-ALL   (50k)
• ANX - Annex : App2 - Methods-ALL   (1039k)
• Final Report - SID5A : Partial rootzone drying: delivering water saving and sustained high quality yield into horticulture   (270k)
Time-Scale and Cost
From: 2004

To: 2009

Cost: £1,117,553
Contractor / Funded Organisations
University - Lancaster, Horticulture Research International, University - Dundee, East Malling Research
Climate Change              
Natural Resource Use              
Protected Cropping              
Sustainable Farming and Food              
Fields of Study