A quantitative analysis of temperature-dependent dormancy changes in Polygonum aviculare seeds

DIEGO BATLLA; ANDREA GRUNDY; KATHERINE DENT; HEATHER CLAY; WILLIAM FINCH-SAVAGE

WEED RESEARCH

Año: 2009 p. 428 - 438

0043-1737

Mathematical models that predict emergence of weed seed banks could be useful tools for determining the most suitable time for weed seedling control and, consequently, should result in a higher efficacy of applied control methods. To achieve this goal in dormant weed species functional relationships should be established between environmental factors regulating dormancy and dormancy changes of seed populations. In the present work we used a simple model and an optimization procedure to quantify the effect of temperature on Polygonum aviculare seed dormancy release and induction based on germination data. Dormancy release rate was inversely related to temperature, showing a logistic decreasing trend which results in no dormancy release for seeds exposed to 20 and 25ºC. In contrast, dormancy induction rates in absolute values were positively associated with temperature showing a logistic trend in which dormancy induction was almost zero at low temperatures and maximal at 25ºC. Derived model parameters were successfully used to simulate dormancy changes of P. aviculare seeds stored under controlled and field conditions. These results suggest that similar model structures could be used to quantify temperature effects on seed dormancy status of other weed species and to develop predictive models of weed emergence.