Modelling the Effect of Temperature, Soil Penetration Resistance, Burial Depth and Seed Weight on Pre-emergence Growth of Weeds

Emergence of the weed speciesPolygonum persicariaL.,Chenopodium albumL. andSpergula arvensisL. was studied experimentally, after burial of pre-germinated seeds at different depths in soil with different penetration resistances at a range of constant temperatures in the laboratory. Final percentages of emergence tended to be unaffected by temperature in the range 10–25 °C, while they were lower at 5 °C. Emergence percentages decreased with increasing soil penetration resistance and increasing burial depth. Rates of emergence increased with increasing temperature, and decreased with increasing soil penetration resistance and increasing burial depth. A physiologically based model was developed to describe the effects of temperature, soil penetration resistance, burial depth and seed weight on pre-emergence growth of seedlings. The model was used to analyse the experimental data in order to obtain insight into the effects of these factors on seedling emergence. The model provided a good description of the trends observed in the experiment.