If you have returned from holiday to a garden full of weeds, you will appreciate that these unwelcome visitors are a persistent problem to even the smallest plots of land. Of course, for farmers the problem is far more serious and understanding the sheer persistence of weeds is a major concern for weed scientists.
One of the key essentials for this understanding comes through the study of weed demography and ENDURE’s team devoted to weed biology and management is hoping to improve this understanding through improved mathematical modelling.
In a recently published Deliverable, DR4.15 Modelling tool software package for end-users and developers , they highlight the suitability of such modelling to improve our understanding of complex systems, but point out that most ecological models are developed, published and then soon forgotten.
Indeed, team leader Niels Holst, from Denmark’s Aarhus University, noted in Weed Research in 2007 that more than 100 weed demographic models had been created around the world. It is rare, he noted, for a model to be re-used and rarer still to find a model that has been developed by one research group and then used by another.
To try and correct this situation, the team has created and made freely available a software package that will enable researchers from around the world to collaborate on their modelling efforts, both in the field of weed science and in the ecological field more generally.
Called Universal Simulator (UniSim), it is already being used for collaborative modelling between ENDURE partners and further afield. For example, Aarhus University is using it for modelling perennial weeds in collaboration with Plant Research International, part of Wageningen University and Research Centre in The Netherlands, and Rothamsted Research in the UK, and is using it to model annual weeds in collaboration with Italy’s Scuola Superiore di Studi Universitari e di Perfezionamento Sant'Anna. It is also being used for collaborative modelling between Aarhus University and the United States Department of Agriculture. For more details on UniSim and how you can download it, go to http://www.ecolmod.org/download.html.
The launch of UniSim follows the group’s work in creating WeedML (Weed Markup Language), which is designed to ease the development of weed demographic models. WeedML is an open, XML (Extensible Markup Language) based format for representing models of the population dynamics of agricultural weeds. You can find out more about it on the WeedML and Weed Traits Database website.
WeedML was inspired by the success of SBML ( Systems Biology Markup Language), which has attracted strong support from systems biology researchers and software engineers. SBML has sought to standardise modelling in the systems biology field and received strong backing from researchers and software engineers, with more than 400 models and 188 software packages available on the SBML website. While such a success may be out of reach for weed modellers, the hope is that UniSim will increase collaboration in this much smaller field and amongst ecological modellers more generally.
Evidence of the desire to collaborate and thus improve our understanding of weed science can also be found in a second Deliverable from the group, DR4.12 Protocals for studying weed biology: Phenology of annual weed species . This explains how the group has sought to develop a phenological protocol (phenology being the sequence of plant development stages following emergence).Having such a protocol will enable researchers to monitor phenological development of annual weedy species during the arable growth season, providing evidence of the amount of time (expressed in day degrees) until the onset of a specific phenological stage and to compare phenological development of a single species within Europe.
ENDURE’s researchers note that this type of information can be used to translate observations on weed traits, such as the timing of the onset of flowering, seed maturation and senescense, in one region to another. This kind of knowledge, they say, is often required for modelling weed growth, but can also be highly valuable to determine the best timing of weed control, the effects of climate change, the relationship between weeds and plant parasitic organisms such as insects, fungi and nematodes, and the competition between weed and crops.
Recent publications from ENDURE’s weed biology and management team
|Report (Deliverable)||Download (pdf)|
|DR4.15 Modelling tool software package for end-users and developers||
ENDURE_DR4.15 [pdf - 153,27 kB]
|DR4.12 Protocals for studying weed biology: Phenology of annual weed species||
ENDURE_DR4.12 [pdf - 1,55 MB]
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