Negative DIF conditions are reducing calcium deficiency in leafy vegetable crops

Under negative DIF conditions plants show fewer Ca deficiency symptoms. Under far red filter with plants the same happens.

Photo of Margit Olle
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I confirm that I am fully aware of the eligibility criteria, and based on its description, I am eligible to apply to the CSV Prize 2017.

  • Yes, I'm eligible

Preferred language

  • English

Organization name

Estonian Crop Research Institute

Year founded


Initiative stage

  • Growth (the pilot has already launched and is starting to expand)

Annual budget in 2017 (USD)

  • Less than $1k

Number of beneficiaries impacted so far

  • 1 - 10

Organization type

  • Nonprofit, NGO, or citizen sector

Secondary Focus Area

  • Rural development

Headquarters location: Country

  • Estonia

Headquarters location: City

Jõgeva alevik

Location(s) of impact

Negative DIF and far red filter have not been used to reduce the calcium deficiency yet. Maybe will be soon in United Kingdom.

Website Margit Olle book about calcium deficiency.

Problem: What problem is this initiative trying to address?

Physiological calcium deficiency is usually related to the inability of the plant to translocate adequate calcium to the affected plant part rather than insufficient Ca levels in the growing medium. Tipburn is a physiological calcium deficiency injury on leafy vegetable crops. Tipburn is a major limitation to production of lettuce. The unpredictability of tipburn and the absence and the absence of control procedures make the problem very serious.

Solution Summary: What is the proposed solution? What do you see as its most promising aspects for creating shared value?

In negative DIF conditions plants remain more compact (Roar Moe from Norway have lots of papers about it). Under negative DIF conditions if plants stay more compact they contain more Calcium and there are fewer Ca deficiency symptoms on plants (Margit Olle discovery, not a patent unfortunately). Negative DIF saves energy, because night lasts for some hours only, and then is the temperature higher, all day time (some 16-18 hours) the temperature is low, therefore the energy is saved. Negative DIF creates a condition when plants grow not very rapidly and since Ca is absorbed only through transpiration process the newly developed tissues can obtain more or adequate amount of calcium and therefore calcium deficiency symptoms does not appear. This disease is very serious, because leading in serius cases to the death of tissues, especially young tissues. Value for all: growers, and consumers. Growers can get more yield of healthy plants. Concumers can eat more healthy vegetables.

Impact: What is the impact of the work to date? Specify both the social and the environmental impact of your work

Social impact: All peoples over the world can benefit from it if they get from shops greenhouse grown vegetables, which store longer and are more nutritious. Environmental impact: Vegetables contain more calcium when they do not grow too fast, and get enough calcium for growth. Plants suffer fewer diseases and insect attacks. In plant nutrition, calcium is often referred to as the plant’s first line of defence. Increased calcium levels in leaf tissue can greatly decrease the pathogen’s ability to invade the leaf. Adequate levels of calcium in plants also aid the plant’s ability to isolate an infection. A plant grown in these conditions contains more calcium, i.e. has better storability. Plants containing more calcium have strong cell walls, which do not allow leakage of cell liquids.

Financial sustainability plan: How is this initiative financially supported? How will you ensure its financial sustainability long-term?

1. Individual donations or gifts 2. Grants - Pilot experiments were supported by Post-doc grant. 3. Corporate contributions 4. Earned income 5. Other Negative DIF saves energy, because night lasts for some hours only, and then is the temperature higher, all day time (some 16-18 hours) the temperature is low, therefore the energy is saved. In negative DIF conditions there is much less electricity or power usage, because long day has lower temperature and short night higher temperature. It means less finances needed for production. The system is very simple, does not need new equipment or investing, to existing greenhouse, just shift the teperature regimes. Easily replicable globally. I would like to start large scale experiments in order to showcase the method to stakeholders

Unique value proposition: What makes your initiative innovative? How does your project differ from other organizations working in the same field?

The method negative DIF is comparable only with my own second discovery: Under far red filter plants stay more compact (not my discovery). Under a far-red filter, such more compact plants contain more Calcium and show fewer Ca deficiency symptoms (my discovery). Other very good methods, such as spraying Ca solutions on leaves of lettuce or covering plants with plastic by night time, needs toomuch labour usage, which makes them very expensive to use.

Founding story: Share a story about the "Aha!" moment that sparked the beginning of this initiative.

I was studnig as Ph. D. student at Agricultural University of Norway and my theme was Ca deficiency in chervil. As I was reading much of this subject I did know that reducing growth rate will reduce Ca deficiency in plants. I also was reading professor Roar Moe article about compactness of plants (i.e. reduced growth rate) in negative DIF conditions. As calcium deficiency decreases with slower growth rate I got the other a'ha.

Where did you hear about the Nestlé Creating Shared Value Prize?

  • Upon recommendation from others


Join the conversation:

Photo of Mouhamadou Moustapha Seck

Interesting. Congratulations.

Photo of Margit Olle

Thank you!

Photo of Mouhamadou Moustapha Seck

You welcome.