Open Access
Table 1.
Effects of cropping system components on the blackgrass life-cycle as simulated by ALOMYSYS (Colbach et al., 2006b; 2007; 2010).
| Cropping system | Intermediate effect | Effect on blackgrass |
|---|---|---|
| Tillage and mechanical weeding | Soil structure | Soil compaction increases mortality of germinated seeds |
| Soil movements = f(soil structure) | Seed burial decreases germination and increases pre-emergent mortality due to insufficient seed reserve. Seeds on soil surface germinate badly because of insufficient seed-soil contact Germinated seeds close to soil surface often die because the top soil dries faster. | |
| Exposes imbibed seeds to light if inverting tool, thus breaking dormancy | ||
| Triggers germination flush if moist soil | ||
| Destroys germinated seeds, seedlings and plants | ||
| Crop | Choice of cultivation techniques | See effects of techniques |
| Occupies space, uses water and nutrients | Decreases components of weed seed production (plant survival, tillers/plant, heads/tiller, flowers/head, seeds/flower) | |
| Seed return to soil seed bank is reduced by crop canopies in multi-annual crops (e.g. grassland, permanent living mulch) | ||
| Sowing date | Crop emergence date | The earlier the weed seedlings emerge relative to the crop, the better they survive and tiller |
| Date of last tillage | The later the last tillage, the more weed seeds have germinated already and are killed by the tillage | |
| Sowing density | Crop density | Increases weed seedling mortality |
| Herbicides | Weed mortality = f(active ingredient, conditions) Weed mortality decreases with plant density, seed depth (for root-acting herbicides) and weed stage | |
Decreases tillering on surviving plants |
||
| Mowing | Destroys tillers and heads. Plants with mature heads die; the remaining tiller again but usually produce less seeds | |
| Nitrogen | Increases flowers/head | |
| Conditions during seed production | Influence dormancy level and germination rates of newly produced seeds | |
| Harvest | Destruction of all plants | |
Each time plants are destroyed, their seed production, if any, is added to the seed bank.
Les statistiques affichées correspondent au cumul d'une part des vues des résumés de l'article et d'autre part des vues et téléchargements de l'article plein-texte (PDF, Full-HTML, ePub... selon les formats disponibles) sur la platefome Vision4Press.
Les statistiques sont disponibles avec un délai de 48 à 96 heures et sont mises à jour quotidiennement en semaine.
Le chargement des statistiques peut être long.