status: Active

Controlling water imbalances to reduce tomato losses

Learning about physiological water imbalances within tomato plants through the use of sap flow and diameter variation sensors

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Field Lab Timeline

    10/24/2020 11:00:00 PM
  • Development of field lab

    Development of field lab
  • 1/4/2021 12:00:00 AM
  • Sensors fitted to beef crop

    Sensors fitted to beef crop
  • 3/15/2021 12:00:00 AM
  • All sensors fitted

    All sensors fitted
  • 3/15/2021 12:00:00 AM
  • Ongoing refinement of climate and irrigation settings

    Ongoing refinement of climate and irrigation settings
  • 4/30/2021 11:00:00 PM
  • Group meeting

    Group meeting
  • 6/30/2021 11:00:00 PM
  • Group meeting

    Group meeting
  • 8/31/2021 11:00:00 PM
  • Group meeting

    Group meeting
  • 11/1/2021 12:00:00 AM
  • Group meeting

    Group meeting
  • 11/30/2021 12:00:00 AM
  • Final report and next steps

    Final report and next steps
For further information hover over the above milestone marks
  • Discussion

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  • Achievements

    July 2021

    Update on progress

    The group met and consolidated and reviewed the last eight weeks data. The key points are:

    • We were not able to pick up the situation where blossom end rot occurs in the beef tomato in advance of it actually happening.
    • There are a number of situations at the site in Yorkshire where the irrigation starting strategy could be improved (either earlier or later).
    • Investigations are being made into automating the starting of irrigation in relation to EC, sap flow, stem diameter and water content.

    Other actions:

    • We should have a new widget to allow a faster interpretation of the data
    • We will send plant data to 2Grow (the sensor company) to see if any relation can be seen with shrinking/ increasing stems with flowering speed
    • Investigate if ‘dangerous’ occurrences can be marked or alarms set.

    Milestone: Group meeting

    March 2021

    All sensors installed

    The sensors have been fitted on the beef and piccolo tomato crops on the Isle of Wight and the cherry tomato crop at the site near Hull. The sensors were fitted when tomato plant stems exceeded 10mm thickness. There have been some issues with getting the stem diameter sensor at the Yorkshire site fitted correctly. This is now in place and reading well. They have seen some ‘knocks’ to the sensors during the weekly crop husbandry. Although these are frustrating all sensors have been adjusted and reading correctly.

    The growers have weekly virtual meetings with the sensor providers to discuss learnings and also maintain an active WhatsApp group for immediate feedback regarding unexpected spikes or drops in sap flow or stem diameter occur.

    Milestone: All sensors fitted

    January 2021

    First sensors installed

    Just a couple of weeks after the sensors were installed into the beef tomato crop, the sensors have enabled the growers to identify some crucial areas to make adjustments:

    • Night screens help avoid light escaping from artificial light in greenhouses and causing night pollution. In the mornings, this is removed. The growers identified that they had been removing the night screen too fast, which decreased transpiration (the sensors showed that stem diameter increased and flow reduced). They believe the stomata were closing as cold air hit the plants when the screen was removed. They have slowed down removal and are seeing less scorch.

    • They are able to keep stem diameter more constant than previously by watering earlier in the day

    Sensors will be fitted onto the piccolo crop and cherry tomato crop in late February.

    Milestone: Sensors fitted to beef crop

    January 2021



    • Reduce splitting in Piccolo vine
    --> Ensuring the irrigation is applied at the right time
    --> Ensuring that the supply is in line with transpiration

    • Reduce Blossom End Rot (BER) in beef tomatoes CV Jack Hawkins
    --> Ensuring that the plant has enough water at all times
    --> Ensuring that the plant is able to recover at the end of the day

    LOCATIONS: Farms located in Yorkshire and the Isle of Wight

    • Stem diameter and sap flow sensors
    • Used to indicate physiological water imbalances in real time
    • Growers and data analysis specialists have constant access to the technology and offer advice as part of their service

    • Fortnightly catch ups and presentations on progress
    • Whatsapp group

    Milestone: Development of field lab

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