Background information

NemaDecide predictions are based on models

NemaDecide predicts the expected population development of the potato cyst nematode, the Columbia root knot nematode as well as the root lesion nematode in relation to crop and cultivar choice. Population development affects possible yield losses. NemaDecide predicts yield loss in potato caused by the presence of these nematode species.
Population development of the potato cyst nematode affects the chance of detection of this nematode. NemaDecide predicts the chance of detection for different sampling methods.
All these predictions are made by using models. More information about the models used is given in the Help file of NemaDecide. All models have been described in scientific publications. Click here for an extensive literature list of these publications.

Background information on the development of NemaDecide

Use of granules in a short cultivation
NemaDecide makes scientific information available for practical application, recent research as well as older research. We are involved in the setup of new research to make the results directly suitable for NemaDecide. In 2005, e.g., an experiment with granules has been carried out on a seed potato field in Firdgum. The setup was such that not only information was gained about the effect of granules on yield but also on population development. This experiment showed that granules cannot prevent reproduction on a susceptible cultivar (Première) in a seed potato crop but that reproduction is lower than without application of granules.
Report experiment Firdgum.pdf (in Dutch)

Effect of growth duration and granules on the reproduction of the potato cyst nematode
The experiment, carried out in Firdgum in 2005, showed that the reproduction of the potato cyst nematode in a short growing season is lower than in a long growing season. Granules were also found to suppress reproduction. The exact relationship between growth duration and reproduction was not yet known. It was neither known whether granules have an effect on reproduction in a longer growing crop. In 2009 PPO, PRI and HLB carried out an experiment in Swifterbant on a G. pallida infested field to find answers to these questions. The Markies cultivar was grown as ware potato and Mocap, Vydate or Nemathorin were broadcasted on part of the field. Population development has been recorded at several points in time during the cultivation. The experiment, financed by the Product Board for Arable Farming, Stichting Proefboerderijen Flevoland, Stichting van Bemmelenhoeve, Bayer, Dupont and Syngenta, yielded good results. Broadcast granular application had a clear effect on yields and population development. The key figures resulting from this experiment have been incorporated into NemaDecide to enable computing of the costs/benefits of granular application for PCN control. After completion, the report of this experiment will be placed on the website.

Application of granules on reclaimed peat soil (dalgrond)
In 2007 HLB conducted, in collaboration with PPO AGV and PRI, an experiment with granules upon commission by the Product Board for Arable Farming and the manufacturers of plant protection products (Bayer, DuPont and Syngenta). The experiment was set up in such a way that the effect of granules could be studied at different population densities. The results will be used in NemaDecide when all data have been analysed to be able to make a good prediction of the nematode densities at which the use of granules on reclaimed peat soil will be cost-effective.
A summarising report about the effect of granules under different conditions will be placed on the website as soon as the data from all experiments have been analysed.

Downloads presentations (in Dutch)

Meloidogyne (PDF 5 MB)
Pratylenchus penetrans (PDF 4 MB)
Potato as catch crop for potato cyst nematodes (PDF 500 KB)
Meloidogyneresistentie in potato (PDF 5 MB)

Newsletters (in Dutch)

May 2010 (PDF)

NemaDecide Knowledge Day

The NemaDecide Knowledge Day on 4 February 2009 at Agrico in Emmeloord drew many visitors. The provision of further information about the Dutch approach of new EU PCN regulations and its impact on the seed potato acreage was an important element of this day. The models implemented in NemaDecide also play an important role in the elaboration of the Dutch approach.

The NemaDecide Knowledge Day was intended for all who are involved in the development of NemaDecide and for all licence holders. There was a lot of interest for the day and the meeting room was hardly big enough. A number of models and their backgrounds were highlighted during the day. The afternoon programme covered the state of affairs concerning the development of NemaDecide 2, the nematode advisory programme that also includes the root lesion nematode (Pratylenchus penetrans) and the root knot nematode (Meloidogyne chitwoodi).
The participants were extremely interested in the presentation of the new PCN regulations taking effect on 1 July 2010. Frans Janssen, Sector Manager Arable Farming of the Netherlands Plant Protection Service (PD), held a clear presentation about the Dutch approach of the EU regulations. The approach has not yet been finalised at all points and the participants were given every opportunity to react and to ask questions. It became clear that the impact on the available seed potato acreage will be considerable and that NemaDecide is an important tool in controlling the PCN problem.

Downloads of all presentation (in Dutch) can be found here: