What is involved is a pioneering experience for Spain, as never before has a first generation of seed potatoes been produced on a large scale by means of aeroponic growth.
The system increases productivity, as more than twenty tubers per plant can be obtained instead of the three or four achieved using conventional methods. It reduces the rate of soil-based diseases and it is a more sustainable system as it needs lower inputs of water and fertilisers. Aeroponics also enables providing precisely the correct amount of both items needed by the plant at each phase of its development.
The aeroponic system of cultivation for the production of first generation seed potatoes is carried out in greenhouses and basically consists of maintaining the roots of the plant in the air and in conditions of total darkness.
In order for the plant and the tubers to develop, nutrients are applied to the roots by means of a nebuliser system, where nutrient-enriched water is sprayed on them periodically. As roots grow in the air, this avoids the contact of the tubers with soil pathogens and production per plant increases considerably decreasing the price of the tuber down substantially.
Just at the right moment
One highly outstanding aspect of this system is that the progress of the tubers can be continually controlled, enabling their harvesting at the moment of optimum growth. In the case of first generation seed potatoes, the most appropriate size is considered to be between 20 and 25mm diameter.
In this way, a homogeneous production can be achieved – not possible with traditional cultivation, given that all the tubers are harvested at the same time and do not show the same development or size.
The conventional production method for first generation seed potatoes is based on high-density plantations, in peat substrate and in greenhouses. Highly labour intensive, with high costs due to the low numbers of tubers produced per plant (between three and four tuber-seeds) the Newco and Neiker-Tecnalia project aims to implement the aeroponic system for a large-scale production of first generation seed potatoes.
The production of seed potatoes throughout all the process follows a specific route map, starting with the in vitro multiplication of plants free of disease. Then, these plants are cultivated to obtain the tuber-seeds or minitubers, which show a high health quality level and are the first generation seeds (prebasic).
These minitubers are the starting material for obtaining the basic seed, in its categories SuperElite and Elite. From this basic seed Certificate A seed can be obtained, commonly employed to produce potatoes for consumption.
Effectively, the Newco and Neiker-Tecnalia research project is precisely aimed at developing the production of seed potatoes throughout its process, something that is not being achieved in Spain but in a very small quantity.
The production of minitubers requires high technological skills and is currently practically non-existent in Spain and Spanish seed potato producers have to import them from countries like France, Holland and Scotland.