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Quantitative description of the effect of stratification on dormancy release of grape seeds in response to various temperatures and water contents.

Wang WQ, Song SQ, Li SH, Gan YY, Wu JH, Cheng HY - J. Exp. Bot. (2009)

Bottom Line: The effect of stratification on dormancy release of grape seeds crossing from the sub- to the supraoptimal range of temperatures and water contents was analysed by modified threshold models.The thermal time approaches effectively quantified dormancy release only at suboptimal temperature, but a quantitative method to integrate the occurrence of dormancy release and induction at the same time could describe it well at either sub- or supraoptimal temperatures.Dormancy release in grape seeds can occur across a very wide range of conditions, which has important implications for their ability to adapt to a changeable environment in the wild.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany, the Chinese Academy of Sciences, Beijing, China.

ABSTRACT
The effect of stratification on dormancy release of grape seeds crossing from the sub- to the supraoptimal range of temperatures and water contents was analysed by modified threshold models. The stratification impacted on dormancy release in three different ways: (i) dormancy was consistently released with prolonged stratification time when stratified at temperatures of <15 degrees C; (ii) at 15 degrees C and 20 degrees C, the stratification effect initially increased, and then decreased with extended time; and (iii) stratification at 25 degrees C only reduced germinable seeds. These behaviours indicated that stratification could not only release primary dormancy but also induce secondary dormancy in grape seed. The rate of dormancy release changed linearly in two phases, while induction increased exponentially with increasing temperature. The thermal time approaches effectively quantified dormancy release only at suboptimal temperature, but a quantitative method to integrate the occurrence of dormancy release and induction at the same time could describe it well at either sub- or supraoptimal temperatures. The regression with the percentage of germinable seeds versus stratification temperature or water content within both the sub- and supraoptimal range revealed how the optimal temperature (T(so)) and water content (W(so)) for stratification changed. The T(so) moved from 10.6 degrees C to 5.3 degrees C with prolonged time, while W(so) declined from >0.40 g H2O g DW(-1) at 5 degrees C to approximately 0.23 g H2O g DW(-1) at 30 degrees C. Dormancy release in grape seeds can occur across a very wide range of conditions, which has important implications for their ability to adapt to a changeable environment in the wild.

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Different stratification behaviours of seeds stratified at a series of temperatures. The final percentages of germinable seeds stratified at a given temperature were plotted and regressed against the stratification time. The regression was according to Equations 2 and 4. In Equation 2, the parameters g1 and g2 were constrained to be shared for all data. Data are means ±SD and the solid lines are the regression lines.
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fig2: Different stratification behaviours of seeds stratified at a series of temperatures. The final percentages of germinable seeds stratified at a given temperature were plotted and regressed against the stratification time. The regression was according to Equations 2 and 4. In Equation 2, the parameters g1 and g2 were constrained to be shared for all data. Data are means ±SD and the solid lines are the regression lines.

Mentions: As mentioned above, stratification exerted three different effects on dormancy release of grape seeds. At temperatures of 0, 3, 6, 10, and 15 °C/5 °C, stratification continuously released seed dormancy with increasing stratification time, presenting a sigmoidal increase on a percentage germination basis, with the maximum effect at 10 °C (Fig. 2A). When stratified at 15 °C and 20 °C, only dormancy release of some seeds could be achieved after certain durations, i.e. 30 d and 10 d, respectively (Fig. 2B). When stratification was at 25 °C, the dormancy status of seeds, as measured by percentage germination, was maintained or increased with increasing stratification time (Fig. 2C). The effect indicated the simultaneous occurrence of dormancy release and induction, which could be modelled by Equation 2 (Fig. 2).


Quantitative description of the effect of stratification on dormancy release of grape seeds in response to various temperatures and water contents.

Wang WQ, Song SQ, Li SH, Gan YY, Wu JH, Cheng HY - J. Exp. Bot. (2009)

Different stratification behaviours of seeds stratified at a series of temperatures. The final percentages of germinable seeds stratified at a given temperature were plotted and regressed against the stratification time. The regression was according to Equations 2 and 4. In Equation 2, the parameters g1 and g2 were constrained to be shared for all data. Data are means ±SD and the solid lines are the regression lines.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2724692&req=5

fig2: Different stratification behaviours of seeds stratified at a series of temperatures. The final percentages of germinable seeds stratified at a given temperature were plotted and regressed against the stratification time. The regression was according to Equations 2 and 4. In Equation 2, the parameters g1 and g2 were constrained to be shared for all data. Data are means ±SD and the solid lines are the regression lines.
Mentions: As mentioned above, stratification exerted three different effects on dormancy release of grape seeds. At temperatures of 0, 3, 6, 10, and 15 °C/5 °C, stratification continuously released seed dormancy with increasing stratification time, presenting a sigmoidal increase on a percentage germination basis, with the maximum effect at 10 °C (Fig. 2A). When stratified at 15 °C and 20 °C, only dormancy release of some seeds could be achieved after certain durations, i.e. 30 d and 10 d, respectively (Fig. 2B). When stratification was at 25 °C, the dormancy status of seeds, as measured by percentage germination, was maintained or increased with increasing stratification time (Fig. 2C). The effect indicated the simultaneous occurrence of dormancy release and induction, which could be modelled by Equation 2 (Fig. 2).

Bottom Line: The effect of stratification on dormancy release of grape seeds crossing from the sub- to the supraoptimal range of temperatures and water contents was analysed by modified threshold models.The thermal time approaches effectively quantified dormancy release only at suboptimal temperature, but a quantitative method to integrate the occurrence of dormancy release and induction at the same time could describe it well at either sub- or supraoptimal temperatures.Dormancy release in grape seeds can occur across a very wide range of conditions, which has important implications for their ability to adapt to a changeable environment in the wild.

View Article: PubMed Central - PubMed

Affiliation: Institute of Botany, the Chinese Academy of Sciences, Beijing, China.

ABSTRACT
The effect of stratification on dormancy release of grape seeds crossing from the sub- to the supraoptimal range of temperatures and water contents was analysed by modified threshold models. The stratification impacted on dormancy release in three different ways: (i) dormancy was consistently released with prolonged stratification time when stratified at temperatures of <15 degrees C; (ii) at 15 degrees C and 20 degrees C, the stratification effect initially increased, and then decreased with extended time; and (iii) stratification at 25 degrees C only reduced germinable seeds. These behaviours indicated that stratification could not only release primary dormancy but also induce secondary dormancy in grape seed. The rate of dormancy release changed linearly in two phases, while induction increased exponentially with increasing temperature. The thermal time approaches effectively quantified dormancy release only at suboptimal temperature, but a quantitative method to integrate the occurrence of dormancy release and induction at the same time could describe it well at either sub- or supraoptimal temperatures. The regression with the percentage of germinable seeds versus stratification temperature or water content within both the sub- and supraoptimal range revealed how the optimal temperature (T(so)) and water content (W(so)) for stratification changed. The T(so) moved from 10.6 degrees C to 5.3 degrees C with prolonged time, while W(so) declined from >0.40 g H2O g DW(-1) at 5 degrees C to approximately 0.23 g H2O g DW(-1) at 30 degrees C. Dormancy release in grape seeds can occur across a very wide range of conditions, which has important implications for their ability to adapt to a changeable environment in the wild.

Show MeSH
Related in: MedlinePlus