Working Group Meetings

Flakkebjerg, 8. October 2008                         

Minutes for Working Group meeting on
Weed Germination and Early Growth

11th Working Group meeting
Monday 15th – Tuesday 16th September 2008
Perugia, Italy

Participants:
Agnieszka Stoklosa (Poland), Anna Bochenek (Poland), Donato Loddo (Italy), Edite Sousa (Portugal), Federica Graziani (Italy), Francesco Tei (Italy), Ilse A. Rasmussen (Denmark), Jack Dekker (USA), Jose Dorado (Spain), Jose Maria Urbano (Spain), Josefine Liew (Sweden), Jukka Salonen (Finland), Kirsten Semb Tørresen (Norway), Lars Andersson (Sweden), Paul Neve (UK).

Chairman of meeting and writing the minutes: Ilse

1. Welcome to Perugia (Francesco Tei)
   Prof. Tei welcomed the WG to the University and Ilse presented the agenda. Ilse also gave a short explanation about the possibilities for reimbursement for some expenses from the EWRS. Everyone will have to pay for themselves now, and will be reimbursed later. EWRS will pay for all meals during the workshop. For young scientists (Agnieszka Stoklosa, Donato Loddo and Josefine Liew) their expenses for accomodation will also be reimbursed. For all, part of their travel expenses above a certain amount each has to pay for themselves will be reimbursed. An e-mail will be sent to all participants with more specific information and requests for their bank information.
2. Introduction to the working group (Ilse A. Rasmussen)
   Ilse gave a short introduction to the WG and earlier activities. Check the website for further information http://www.ewrs.org/GEGWG/index.html .
3. Brief outline of the common experiment (Ilse A. Rasmussen)
   Ilse gave a brief presentation of the earlier and present common experiments. Please see the presentatin on the website.
4. Presentation of results from 2006 experiment (all papers and presentations will be available at a website with login for participants of the experiment. Info on this will be sent out later)
   1. data analysis with the disturbance model (Jack Dekker)
      Jack gave a long and interesting talk about his ideas about how the data from the first experiment (established in 2005, counted in 2006 and for some locations 2007) could be presented. He suggested to write a first publication, which included a description of materials and methods, and then presentation of data from only the undisturbed plots. Jack found especially the late emerence interesting. There was some discussion as to the data he used for cropping systems, treatments etc. in the field, where the seedlot was collected. There seems to have been some confusion as to whether he wanted historical data (for the past 5-10 years) or specific data for 2005-2006. We came to the conclusion that what he needs is historical data. Jack will send out requests for this soon.
      Having worked with the data from 2005-06, Jack found it important that the data from the new round of the experiment (etablished 2007, still running) should be entered in a common format easy to use. Jack wil formulate a new template by Nov. 1st, 2008. Ilse will send this out and all participants must return this template with 2007-08 data by Dec. 1st, 2008.
      Jack also requested that all participants from the first round, which have kept the experiment in 2007 and made disturbances and counted emergence send him the data (Ilse will include a request for this when requesting for the new data).
      Ilse will explore the possibilities to have a "safe" website, where all participants can access the data, which will be stored in a common format.
   2. Emergence before and after disturbance for each country (Kirsten Tørresen)
      Kirsten had made figures comparing emergence before and after disturbance, which could make a basis for the second publication. (I seem to have noted something about statistics/ANOVA here, but don't remember the exact discussion. Does anyone else?).
   3. Climate data (Paul Neve)
      Paul had compared some of the emergence events with the climate and found some interesting trends.

This all led to a discussion of how the "window of opportunity" for germination and emergence of C. album can be defined, which in fact may give rise to a third paper. First of all, the period where the soil is too cold (or frozen) for C. album to emerge. This defines the earliest possible emergence in spring in those locations where the winter goes below this temperature. Paul promised to look at the data from the experiments and try to find a common factor – e.g. lowest soil or air temperature where emergence occurred – which defined first possible emergence. In addition, all participants in the first round will look at historically first planting dates and compare this with the parameter Paul has found. In the autumn, the end of emergence could be defined  by the first frost. Paul tries also to find a common factor here. Also high temperatures and/or low or high soil moisture may be limiting for emergence. Paul will look at all these correlations and send out his findings before Oct. 1st.
5. Discussion of publication plans (Jack Dekker, others?)
   Much of this had been discussed during the previous point. Jack pointed out that a very important part of the paper is the materials and methods. Ilse promised to start working on this, and as it will very likely require some work to get all the information straight, she is aiming to have this section complete by Jan. 1st, 2009.
6. Share feedback on 2008 common experiment and presentation of preliminary results from each participating group (All)
   We began with a short discussion of the maternal environment experiment planned by Paul Neve and carried out by some of the participants. Unfortunately it seemed that at many locations, no or very little emergence had occurred, since no disturbance was carried out. In addition, the very dry period of early summer in some locations had stunted the growth of the plants. It was briefly discussed whether the plants should have been irrigated, but since this would contradict the whole idea of different environments, it was agreed that this was not the solution. It was discussed how to establish the nurseries: should the seeds be sown in pots and transplanted, should disturbance be carried out (which could risk confusing the sown seeds with local seeds emerging close to the rows), should the seeds be sown in special seedbeds with lighter soil mixture on top etc. Paul will go back and think about the possibilities, and write a new protocol for the establishment for the next turn of the experiment. It turns out that at least four nurseries (Finland, Czeck republic, Portugal and Illinois, USA) have produced enough seed for the next part of the experiment to be carried out. Paul will also ponder whether, how and when this should be done, and write a protocol. First of all he will write a protocol for how to store the harvested seed. Lars said that in all cases, the experiment should be repeated.
   After this, all participants in the common experiment presented their results – those not present were presented by Ilse. The presentations can be found at the safe website. There were many different ways of presenting the data, which gave rise for new discussions. Also a few deviations from the protocol were described (soil mixture including the addition of superphosphate, disturbance timings, placement of lutrasil within the wire cages etc.) – deliberate as well as misunderstandings. It was discussed, that while the deviations may make the materials & methods section more difficult to write, the data derived will be much more robust, if they point to the same conclusions with so many different treatments.
7. Discussion of continuation of experiment (Ilse A. Rasmussen)
   As many locations as possible will continue the experiment through 2009. No disturbances will be carried out in the autumn, in spring 2009 the same procedure as in 2008 will be carried out.
8. Other working group activities (Ilse A. Rasmussen)
   Ilse encouraged the group members to submit abstracts for the 2010 EWRS symposium in Hungary. This could possibly result in a session on our topic. The abstracts could be both on our common experiment(s) but also on other related topics.
   The possibility to initiate new common experiments was discussed. Ilse admitted that it had been a lot of work to make the protocol, collect the seeds, collect the data etc., and said that while she would participate in a new experiment if possible, she would not take lead or responsibility. Trying to get funding for new experiments was discussed. It was agreed, that it would not likely be possible to get funding for just our experiment, it would have to be a part of a larger project. Relevant subjects could be Integrated Weed Management and/or Climate Change. The reaction of well-known species to climate change and/or the risk for new invasions were mentioned as well as decision support/prediction. For both, our extensive experience with experients under different climatic and soil conditions would be very relevant. New species to consider for such research were suggested: Conyza, Lolium, Bromus. For EU projects, it is very important that we already now start to influence lobbying for including this in a new call. EWRS will work for including IWM in a call. Paul will try to explore possibilities.
9. Possible funding (Paul Neve).
   See above.
10. Future plans (Ilse A. Rasmussen)
    Our next meeting will be at the EWRS 2010 Symposium in Hungary. Ilse was encouraged to try to get more than just 1½ hour for a WG meeting – it could be a day before or after the symposium, if this did not interfere with other activities.
    Smaller groups working on drafts for papers on our common experiment may meet during 2009.
11. Short offered presentations/updates on research activities of WG participants (max. 15 minutes each). The presentations can be found at the private section of the website.
    1. Agnieszka Stokłosa: "Influence of light and temperature on Avena fatua and Bromus secalinus germination".
    2. Kirsten S. Tørresen: “Germination and dormancy of volunteer spring turnip rape”
    3. Paul Neve: Emergence simulation model for crops & weeds.
    4. Donato Loddo: Model for weed emergence in maize using soil temperature and moisture.
    5. Jose Urbano: "Study of emergence of Chenopodium album in southern Spain during 3 years".
    6. Jose Dorado & Edite Sousa: Predicting weed emergence in maize crops under two contrasting climatic conditions.
    7. Anna Bochenek: Hydrotime analysis of Centaurea cyanus seed dormancy relief and induction.
    8. Federica Graziani: "Weed population dynamics in maize crop charaterized by high and low weed density"
12. Closing of meeting and goodbye