Ammonia reduction for improved growth of organic basil
One of our ‘Deutschlandstipendium’ scholarship holders wins Green Challenge
Improving the growth of organic basil ‑ specifically, by reducing the concentration of ammonia in organic fertilisation ‑ was the focus of a Master’s thesis by Christian Frerichs. Frerichs, who studied agribusiness and food industry management at Osnabrück University of Applied Science and was one of our ‘Deutschlandstipendium’ scholarship holders, explains the significance of ammonia in growing organic basil. Joining him for our interview is his mentor Eckhard Schlüter, one of Klasmann-Deilmann’s product advisers who specialises in substrates for organic cultivation.
You won first prize for your project in the Green Challenge. How did that feel?
Christian Frerichs: It’s a great honour for me to have won the first prize at an academic conference. The best thing about it for me was that I am now known in horticultural-research circles, which means networking opportunities.
What did you find out in your experiments with organic basil?
Christian Frerichs: This research showed that potted basil is a crop which is sensitive not only to ammonium but also to ammonia. In organic cultivation, it’s necessary to fertilise with nitrogen ‑ a crucial nutritional element ‑ in organic form. However, organic nitrogen can’t be taken up directly by the roots but is converted into ammonium subsequent to fertilisation, and converted into nitrate only after several days or weeks have elapsed. As ammonium levels build up, the pH of the growing medium frequently rises, which may lead to increased release of gaseous ammonia.
In the ‘real world’, how can a plant nursery put your findings into practice?
Christian Frerichs: My findings can be translated into specific measures in terms of the nature and level of organic fertilisation and how a substrate should be put together. I was also able to substantiate the positive influence of high-quality green compost.
Eckhard Schlüter: Hypotheses had already been formed on certain aspects of this topic, and we have explored these propositions in the past. Thanks to Christian Frerichs’ painstaking and systematic research, we now have scientifically supported facts to enhance our advisory services and product development activities in the organic cultivation of potted herbs.
Why did you settle on this topic?
Christian Frerichs: I had already investigated the ammonium sensitivity of potted basil in my Bachelor’s thesis. Following on from this, I then wanted to find out the extent to which ammonia ‑ a different substance, which is also released after organic fertilisation ‑ is causal for lower yields and crop damage. A particular challenge in my Master’s project was measuring the ammonia. This is a gaseous compound for which an established measurement technique is not yet available. I therefore had to develop a metrological system for my own use. Thanks to financial support from Klasmann-Deilmann, I was indeed able to put my ideas into practice. The company provided me with both the equipment I needed for this system, and the substrates and fertilisers that I used in the fertilisation experiments.
Eckhard Schlüter: Organic-grade basil is by far the most important of all potted-herb crops. So we have a long track record of joining forces with Osnabrück University of Applied Science to explore issues relating to its cultivation ‑ involving fertilisation, substrates and sciarid infestation. And, in some respects, Christian Frerichs’ research ‑ both his Bachelor’s and his Master’s ‑ builds on this groundwork.
How did the contact with Klasmann-Deilmann come about with your scholarship under the ‘Deutschlandstipendium’ scheme?
Christian Frerichs: This scholarship funded by Klasmann-Deilmann has enabled me to place my studies on a financially sound footing. Conversely, I hope the findings obtained from my Bachelor’s and Master’s research will benefit the company as well. Even when the scholarship period was over, I remained in close contact with Mr Schlüter, who lent me his expertise with the experiments.
Eckhard Schlüter: I was delighted to be able to monitor the progress of these trials. A distinctive feature of Christian Frerichs’ work was its strong real-world application: it scientifically investigated specific questions arising from horticultural production. A particular priority for me was that this practical focus be incorporated into the experimental design and into the discussion of the results.
What are your plans for the future?
Christian Frerichs: I completed my Master’s degree on 6 October 2017, since when I have been working at the Borken district office of the North Rhine-Westphalia Chamber of Agriculture. Here I’m responsible for a project on the reduction of nitrate leaching from land used for growing vegetables. The focus is on spinach cultivation. For me, this project is a way of developing my knowledge and skills further ‑ whereas, over the last three years, I was looking at the nitrogen balance in substrates, in this new research the emphasis is on the nitrogen balance in soil. My aim is, once the project is properly up and running, to publish a doctoral thesis on this topic as well.
Eckhard Schlüter: Of course, it makes us proud that our support has helped launch a highly promising research career. We‘re sure that, as in his previous work, Christian Frerichs will approach his new project with great passion and scientific rigour, and wish him all the very best in his future endeavours.
Thank you for talking to us, and the best of success for the future!
&feature=youtu.be”>his video for Green Challenge.