A quantitative analysis of temperature-dependent dormancy changes in Polygonum aviculare seeds |
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| Authors: | D BATLLA A GRUNDY† K C DENT† H A CLAY† & W E FINCH-SAVAGE† |
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| Institution: | I.F.E.V.A./Cátedra de Cerealicultura, C.O.N.I.C.E.T./Facultad de Agronomía, Universidad de Buenos Aires, Argentina;, and Warwick HRI, Warwick University, Wellesbourne, Warwick, UK |
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| Abstract: | Mathematical models that predict emergence of weed seedbanks 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 optimisation 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 decreasing logistic trend that results in no dormancy release for seeds exposed to 20 and 25°C. 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 25°C. Derived model parameters were 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. |
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| Keywords: | dormancy germination knotgrass predictive model temperature weed seedbank |
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