Tommaso is involved in several projects at WUR, and all of them merged to one final goal: Reducing the emissions of the greenhouse horticulture sector and reach a complete circular greenhouse system. For such an intense objective, Tommaso is helping to developing technology and furthering the knowledge on greenhouse crop nutrition.
Ion Specific Cultivation: Optimization of fertilization with ion-specific sensors
The current system of nutrition dosing in greenhouse horticulture is based on adjustments once every 7-14 days after analysis of a sample of the drain solution. This works well in itself, but it still has a lot to improve. This project, financed by several partners (Glastuinbouw Nederland, Top Sector T&U (LNV), Interpolis, The Sensor Factory, Van Iperen BV, Priva BV, T. Stolze Installatietechniek BV, Royal Pride BV) aims to test an improved ion-specific meter that can provide fast and in-situ knowledge of the nutrients dynamics and allow to following more accurately the plant growth. All this knowledge, combined with a digital decision-making system (Fertilization Advice Tool) will certainly lead to optimizing grower's fertilization, which is expected to deliver more yield/quality. In addition, this reduces the need to discharge drain water and therefore reducing the emissions.
The role of Tommaso within this project consists of monitoring the nutrient solutions dynamic as well as the functioning of the system. The complexity of such a combination of data and equipment requires in fact a close expert eye as long as it will not be automated. In addition, it is Tommaso's responsibility to sit with the technical partners and find solutions together.
Cultivation with sodium (Na):
The Dutch greenhouse horticulture already uses water very efficiently. However, sodium represents the main bottleneck for total water reuse. Sodium is toxic for plants and it has a tendency to accumulate in the nutrient solution. For several years, the growers used to discharge the drainage water when the sodium level reached certain levels (experience-based). This project aimed to investigate deeper which are the real sodium limit for the main dutch greenhouse crops (cucumber, tomato, sweet pepper, gerbera, rose, phalaenopsis), in order to give the growers the best insights to deal with sodium accumulation in the future. In between this large project, Tommaso has specifically investigated the possibility to use a split-root set up as a technical solution to remove more sodium from the nutrient solution.
Plasma Activated Water (PAW) as source of NO3 for USDA "organic" cultivation:
The future for Greenhouse Horticulture is Green. In USDA cultivation, provided that "organic" fertilizers are used, soilless systems are recognized as "organic" cultivation systems. However, no directly absorbable nitrogen fertilizers have admissions for usage in these organically grown crops. As a result, it is difficult for growers to dose the right amount of nitrogen in organic form.
WUR was asked to investigate whether PAW can be used for "organic" cultivation ("USDA approved"). PAW is a direct source of NO3. PAW is formed via air electrocution. By a bolt of lightning, a plasma is formed: in it, the nitrogen (N2) and oxygen (O2) break down into reactive components. When the plasma is conducted through water, these components form connections with each other. When these new combinations come into contact with water (H2O), new reactive oxygen and reactive nitrogen compounds are formed.
Within this project, Tommaso is monitoring the nutrient solutions made with the PAW, as well as the control treatment (standard organic nitrogen source). Several parameters have to be controlled in order to recreate the best growth condition for the crop such as microorganism activity, pH and NO3, NH4 and NO2 levels. In addition, the crop runs with a closed irrigation system, so that all the drainage water is recirculated. This requires additional attention over the system.