Identifying key components of weed beet management using sensitivity analyses of the GeneSys‐Beet model in GM sugar beet

Abstract

P>Genetically-modified (GM) sugar beet varieties tolerant to non-selective herbicides would be useful for managing weed beet, an annual form of Beta vulgaris impossible to eliminate with herbicides in sugar beet. However, it is highly probable that the h

Using a sensitivity analysis of a weed dynamics model to develop sustainable cropping systems. II. Long-term effect of past crops and management techniques on weed infestation

“…autumn-emerging with little dormancy and seeds with low persistence) and completed with similar studies (e.g. Tricault et al 2009). However, the present methodology needs to be adapted to truly multi-specific weed dynamics models (Colbach et al 2010 a ; Gardarin et al in press .)…”

“…the spring-emerging broad-leaved crop relative, Beta vulgaris spp. vulgaris , Tricault et al 2009), with slightly different conclusions resulting from the difference in species characteristics. For instance, curative operations (e.g.…”

“…The crop ranking was analysed with a linear regression explaining χ 1 as a function of crop characteristics (Table 2):To illustrate the quantitative effects of crop species characteristics, the relative effect on weed seed production was calculated from regression parameters p as 10 pv −1, where v was the variation tested for the species characteristic. This indicator has already been used successfully in previous sensitivity analyses (Tricault et al 2009) and is the backtransformed ratio of the effect of the variation in the linear regression relative to zero variation.…”

“…In order to test a large range of possible combinations of crop successions and management techniques, a global sensitivity analysis of the model to cropping system variables was run, based on Monte Carlo simulations where all input variables were made to vary randomly and simultaneously (Saltelli et al 2000). This procedure has already been used in a previous sensitivity analysis with ‘weed=f (cropping system)’ models and is useful for ranking variables over a large range of situations while taking into account the interactions between the variables (Colbach et al 2004; Tricault et al 2009).…”

Meta-modelling of the impacts of regional cropping system scenarios for phoma stem canker control

“…To be relevant, meta-models should be based on in silico scenario design, and explore the most significant variables, in a realistic range. This can be ensured by involving stakeholders in scenario design, instead of researchers (e.g., Colbach et al, 2010;Lautenbach et al, 2009;Wechsung et al, 2000) or by simulation (e.g., Tricault et al, 2009;Bergez et al, 2010). The more generic scenarios could remain theoretical: (1) their in-field local feasibility could not have been assessed, but by contrast it is a 'given constraint' in a participatory approach (e.g., Anderson et al, 1998); (2) drivers of cropping system change could not have been highlighted (i.e., local priorities; Dougill et al, 2006); (3) cost-effectiveness of such changes may have been poorly estimated as compared to their direct assessment by stakeholders (e.g., Voinov and Bousquet, 2010).…”