Development of a thermal time model for Polygonum aviculare l. dormancy loss based on changes in seed population thermal parameters

DIEGO BATLLA; ROBERTO LUIS BENECH-ARNOLD

Salamanca, España

Workshop; Seventh International Workshop on Seeds; 2002

Seed Science Society

Development of a thermal time model for Polygonum aviculare L. dormancy loss based on changes in seed population thermal parameters. Diego Batlla and Roberto Benech-Arnold, Department of Plant Production, Faculty of Agronomy, University of Buenos Aires, Av. San Martín 4453, C1417DSE-Buenos Aires, Argentina.   A population-based simulation model for P. aviculare dormancy loss was developed. The model is based on quantitative relationships established between changes in the temperature range permissive for germination in relation to after-ripening temperature. For this purpose, changes in the mean lower limit temperature for germination were related to the accumulation of thermal after-ripening time units under a threshold temperature for dormancy to occur. On the other hand, the model also permits the prediction of changes in the distribution within the seed population of the lower limit temperature for germination in relation to changes in seeds dormancy status. Model performance was evaluated against independent data showing acceptable prediction of timing and percentage of weed emergence under field and controlled conditions.   Preferred sessions: (First choice) Seed germination and dormancy (Modelling germination and dormancy) or Seed ecology (Ecology of germination). Oral presentation.