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Carol C. Baskin - One of the best experts on this subject based on the ideXlab platform.
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Seasonal changes in the germination responses of Buried Seeds of three native eastern North American winter annuals
Plant Species Biology, 2003Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Long-term studies of seasonal changes in temperature and light : dark requirements for germination were conducted on Seeds of Plantago virginica (87 months), Silene antirrhina (32.5 months) and Triodanis perfoliata (36.5 months), Buried under natural temperature regimes in central Kentucky, USA. Seeds of P. virginica exhibited an annual conditional dormancy/non-dormancy cycle; thus, the species has the potential to behave as a facultative winter annual. Seeds of T. perfoliata and S. antirrhina had an annual dormancy/non-dormancy cycle, but dormancy induction was not completed until April or May. Thus, depending on the year, 3–21% and 1–97% of the S. antirrhina and T. perfoliata Seeds, respectively, germinated in March and these species also have the potential to behave as facultative winter annuals. Data from long-term Buried Seeds studies in central Kentucky are now available for 16 native (including the three species reported in this paper) and nine non-native winter annuals of eastern North America. Buried Seeds of non-natives, as well as those of natives whose geographic range extends beyond eastern North America, tend to have a conditional dormancy/non-dormancy cycle, while those of natives with a range restricted to eastern North America tend to have a dormancy/non-dormancy cycle. However, testing of this hypothesis will have to await data for more winter annuals so that a phylogenetically independent analysis can be conducted.
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Effect of Seasonal Temperature Changes on Germination Responses of Buried Seeds of Agalinis fasciculate (Scrophulariaceae), and a Comparison with 12 Other Summer Annuals Native to Eastern North America
Plant Species Biology, 1998Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Seeds of Agalinis fasciculata, a native eastern North American summer annual, were dormant at maturity inautumn and thus did not germinate in light or in darkness at 12/12 hdaily temperatures of 15/6,20/10, 25/15,30/15 and 35/20°C.Buried Seeds exposed to natural temperature changes in Lexington, Kentucky (USA) for 53 months came out of dormancy in late autumn and winter and re-entered it in late spring and early summer of each year. Non-dormant Seeds germinated to 60–100% in light at 20/10°C. Stratification at 5°C broke dormancy, and nondormant Seeds entered dormancy during exposure to 25/15 or 30/15°C. Light was required for germination, but some Seeds could be light-stimulated during stratification. Seeds stratified in light had a broader temperature range for germination than those stratified in darkness and tested in light. Buried Seeds of 11 of the 12 previously-studied native eastern North American summer annuals exhibited seasonal changes intheir dormancy states. As Buried Seeds of the 12 species began to come out of dormancy during winter, they germinated only at high temperatures, but with additional stratification the minimum temperature for germination decreased, which is a Type 2 temperature response pattern. As Seeds of A. fasciculata began to come out of dormancy during stratification, they germinated at an intermediate temperature (20/10°C), but with additional stratification the maximum temperature for germination increased and the minimum temperature decreased, which is a Type 3 pattern. This is the first report of a Type 3pattern in a summer annual and in the Scrophulariaceae. However, the ecological significance, if any, of Type 3 in A. fasciculata Seeds is unknown and may reflect more about the past history of the species or its ancestors than it does about present-day ecological adaptations to the habitat.
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A comparative study of the seed germination biology of a narrow endemic and two geographically-widespread species of Solidago (Asteraceae). 2. Germination responses of Buried Seeds in relation to seasonal temperature cycles
Seed Science Research, 1997Co-Authors: Jeffrey L. Walck, Jerry M. Baskin, Carol C. BaskinAbstract:Seeds of the narrow-endemic Solidago shortii and of the geographically-widespread S. altissima and S. nemoralis collected and Buried in 1992 and 1993 were incubated in light and in darkness at 15/6°, 20/10°, 25/15°, 30/15° or 35/20°C following various periods of burial in soil in a non-temperature-controlled glasshouse. At maturity in November, Seeds of the three species germinated to 0–1% in light at 15/6°C and to 10–77% at 20/10°, 25/15°, 30/15° and 35/20°C. Seeds exhumed each April from 1993 to 1996 and incubated in light at 15/6° and 20/10°C germinated to ≥83% and ≥90%, respectively, whereas those exhumed each September of 1993–96 germinated to ≤2%and ≤40%, respectively. At 25/15°, 30/15° and 35/20°C in light, Seeds of S. altissima and S. shortii germinated to ≥52% and those of S. nemoralis to ≥19/, regardless of when they were exhumed. Timson's index, which integrates percentages, rates and times for onset of germination, was higher at all temperature regimes for Seeds exhumed in April 1995 than for those exhumed in September 1995. Freshly-matured Seeds of the three species germinated to 0–11% in darkness. Furthermore, regardless of when they were exhumed, Seeds of S. altissima and S. nemoralis incubated in darkness germinated mostly to only 0–9% over the range of temperature regimes. In contrast, ≤88% and ≤6% of the Seeds of S. shortii exhumed and incubated in darkness each April and September of 1993–96, respectively, germinated, ≤1% of them germinating while Buried in soil. Thus, although Buried Seeds of all three species exhibited an annual conditional dormancy/non-dormancy cycle, only those of S. shortii exhibited cyclic changes in their germination response in darkness.
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A comparative study of the seed germination biology of a narrow endemic and two geographically-widespread species ofSolidago(Asteraceae). 2. Germination responses of Buried Seeds in relation to seasonal temperature cycles
Seed Science Research, 1997Co-Authors: Jeffrey L. Walck, Jerry M. Baskin, Carol C. BaskinAbstract:AbstractSeeds of the narrow-endemicSolidago shortiiand of the geographically-widespreadS. altissimaandS. nemoraliscollected and Buried in 1992 and 1993 were incubated in light and in darkness at 15/6°, 20/10°, 25/15°, 30/15° or 35/20°C following various periods of burial in soil in a non-temperature-controlled glasshouse. At maturity in November, Seeds of the three species germinated to 0–1% in light at 15/6°C and to 10–77% at 20/10°, 25/15°, 30/15° and 35/20°C. Seeds exhumed each April from 1993 to 1996 and incubated in light at 15/6° and 20/10°C germinated to ≥83% and ≥90%, respectively, whereas those exhumed each September of 1993–96 germinated to ≤2%and ≤40%, respectively. At 25/15°, 30/15° and 35/20°C in light, Seeds of S.altissimaandS. shortiigerminated to ≥52% and those of S.nemoralisto ≥19/, regardless of when they were exhumed. Timson's index, which integrates percentages, rates and times for onset of germination, was higher at all temperature regimes for Seeds exhumed in April 1995 than for those exhumed in September 1995. Freshly-matured Seeds of the three species germinated to 0–11% in darkness. Furthermore, regardless of when they were exhumed, Seeds ofS. altissimaandS. nemoralisincubated in darkness germinated mostly to only 0–9% over the range of temperature regimes. In contrast, ≤88% and ≤6% of the Seeds ofS. shortiiexhumed and incubated in darkness each April and September of 1993–96, respectively, germinated, ≤1% of them germinating while Buried in soil. Thus, although Buried Seeds of all three species exhibited an annual conditional dormancy/non-dormancy cycle, only those ofS. shortiiexhibited cyclic changes in their germination response in darkness.
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effect of flooding on annual dormancy cycles in Buried Seeds of two wetland carex species
Wetlands, 1996Co-Authors: Carol C. Baskin, Edward W. Chester, Jerry M. BaskinAbstract:Buried Seeds ofCarex comosa andC. sticta were exposed to nonflooded and flooded conditions and natural seasonal temperature changes for 30.5 and 33 mo, respectively. At 1-, 2- or 6-mo intervals, exhumed Seeds were tested for germination in light and darkness over a range of daily thermoperiods. Freshly-matured Seeds of both species were conditionally dormant; maximum germination was at 35/20°C, in light. Dormancy decreased in nonflooded and flooded Seeds ofC. comosa during late autumn and winter, but the decrease was greater in flooded than in nonflooded Seeds. Nonflooded and flooded Seeds ofC. stricta gained the ability to germinate in light during the first summer of burial and in darkness during the following winter. Seeds of neither species germinated while they were Buried in pots of soil under either nonflooded or flooded conditions in the nonheated greenhouse. Nonflooded and flooded Seeds of both species incubated in light and flooded Seeds ofC. comosa incubated in darkness had an annual conditional dormancy/nondormancy cycle, being conditionally dormant in summer and autumn and nondormant in spring. However, nonflooded Seeds ofC. comosa incubated in darkness remained dormant, germinating to only 1%. Most nonflooded and flooded Seeds ofC. stricta incubated in darkness had an annual dormancy/nondormancy cycle, being dormant in summer and nondormant in spring. Thus, flooding influenced the annual changes in dormancy states of Buried Seeds ofC. comosa, but it had no effect on Seeds ofC. stricta.
Jerry M. Baskin - One of the best experts on this subject based on the ideXlab platform.
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Seasonal changes in the germination responses of Buried Seeds of three native eastern North American winter annuals
Plant Species Biology, 2003Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Long-term studies of seasonal changes in temperature and light : dark requirements for germination were conducted on Seeds of Plantago virginica (87 months), Silene antirrhina (32.5 months) and Triodanis perfoliata (36.5 months), Buried under natural temperature regimes in central Kentucky, USA. Seeds of P. virginica exhibited an annual conditional dormancy/non-dormancy cycle; thus, the species has the potential to behave as a facultative winter annual. Seeds of T. perfoliata and S. antirrhina had an annual dormancy/non-dormancy cycle, but dormancy induction was not completed until April or May. Thus, depending on the year, 3–21% and 1–97% of the S. antirrhina and T. perfoliata Seeds, respectively, germinated in March and these species also have the potential to behave as facultative winter annuals. Data from long-term Buried Seeds studies in central Kentucky are now available for 16 native (including the three species reported in this paper) and nine non-native winter annuals of eastern North America. Buried Seeds of non-natives, as well as those of natives whose geographic range extends beyond eastern North America, tend to have a conditional dormancy/non-dormancy cycle, while those of natives with a range restricted to eastern North America tend to have a dormancy/non-dormancy cycle. However, testing of this hypothesis will have to await data for more winter annuals so that a phylogenetically independent analysis can be conducted.
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Effect of Seasonal Temperature Changes on Germination Responses of Buried Seeds of Agalinis fasciculate (Scrophulariaceae), and a Comparison with 12 Other Summer Annuals Native to Eastern North America
Plant Species Biology, 1998Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Seeds of Agalinis fasciculata, a native eastern North American summer annual, were dormant at maturity inautumn and thus did not germinate in light or in darkness at 12/12 hdaily temperatures of 15/6,20/10, 25/15,30/15 and 35/20°C.Buried Seeds exposed to natural temperature changes in Lexington, Kentucky (USA) for 53 months came out of dormancy in late autumn and winter and re-entered it in late spring and early summer of each year. Non-dormant Seeds germinated to 60–100% in light at 20/10°C. Stratification at 5°C broke dormancy, and nondormant Seeds entered dormancy during exposure to 25/15 or 30/15°C. Light was required for germination, but some Seeds could be light-stimulated during stratification. Seeds stratified in light had a broader temperature range for germination than those stratified in darkness and tested in light. Buried Seeds of 11 of the 12 previously-studied native eastern North American summer annuals exhibited seasonal changes intheir dormancy states. As Buried Seeds of the 12 species began to come out of dormancy during winter, they germinated only at high temperatures, but with additional stratification the minimum temperature for germination decreased, which is a Type 2 temperature response pattern. As Seeds of A. fasciculata began to come out of dormancy during stratification, they germinated at an intermediate temperature (20/10°C), but with additional stratification the maximum temperature for germination increased and the minimum temperature decreased, which is a Type 3 pattern. This is the first report of a Type 3pattern in a summer annual and in the Scrophulariaceae. However, the ecological significance, if any, of Type 3 in A. fasciculata Seeds is unknown and may reflect more about the past history of the species or its ancestors than it does about present-day ecological adaptations to the habitat.
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A comparative study of the seed germination biology of a narrow endemic and two geographically-widespread species of Solidago (Asteraceae). 2. Germination responses of Buried Seeds in relation to seasonal temperature cycles
Seed Science Research, 1997Co-Authors: Jeffrey L. Walck, Jerry M. Baskin, Carol C. BaskinAbstract:Seeds of the narrow-endemic Solidago shortii and of the geographically-widespread S. altissima and S. nemoralis collected and Buried in 1992 and 1993 were incubated in light and in darkness at 15/6°, 20/10°, 25/15°, 30/15° or 35/20°C following various periods of burial in soil in a non-temperature-controlled glasshouse. At maturity in November, Seeds of the three species germinated to 0–1% in light at 15/6°C and to 10–77% at 20/10°, 25/15°, 30/15° and 35/20°C. Seeds exhumed each April from 1993 to 1996 and incubated in light at 15/6° and 20/10°C germinated to ≥83% and ≥90%, respectively, whereas those exhumed each September of 1993–96 germinated to ≤2%and ≤40%, respectively. At 25/15°, 30/15° and 35/20°C in light, Seeds of S. altissima and S. shortii germinated to ≥52% and those of S. nemoralis to ≥19/, regardless of when they were exhumed. Timson's index, which integrates percentages, rates and times for onset of germination, was higher at all temperature regimes for Seeds exhumed in April 1995 than for those exhumed in September 1995. Freshly-matured Seeds of the three species germinated to 0–11% in darkness. Furthermore, regardless of when they were exhumed, Seeds of S. altissima and S. nemoralis incubated in darkness germinated mostly to only 0–9% over the range of temperature regimes. In contrast, ≤88% and ≤6% of the Seeds of S. shortii exhumed and incubated in darkness each April and September of 1993–96, respectively, germinated, ≤1% of them germinating while Buried in soil. Thus, although Buried Seeds of all three species exhibited an annual conditional dormancy/non-dormancy cycle, only those of S. shortii exhibited cyclic changes in their germination response in darkness.
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A comparative study of the seed germination biology of a narrow endemic and two geographically-widespread species ofSolidago(Asteraceae). 2. Germination responses of Buried Seeds in relation to seasonal temperature cycles
Seed Science Research, 1997Co-Authors: Jeffrey L. Walck, Jerry M. Baskin, Carol C. BaskinAbstract:AbstractSeeds of the narrow-endemicSolidago shortiiand of the geographically-widespreadS. altissimaandS. nemoraliscollected and Buried in 1992 and 1993 were incubated in light and in darkness at 15/6°, 20/10°, 25/15°, 30/15° or 35/20°C following various periods of burial in soil in a non-temperature-controlled glasshouse. At maturity in November, Seeds of the three species germinated to 0–1% in light at 15/6°C and to 10–77% at 20/10°, 25/15°, 30/15° and 35/20°C. Seeds exhumed each April from 1993 to 1996 and incubated in light at 15/6° and 20/10°C germinated to ≥83% and ≥90%, respectively, whereas those exhumed each September of 1993–96 germinated to ≤2%and ≤40%, respectively. At 25/15°, 30/15° and 35/20°C in light, Seeds of S.altissimaandS. shortiigerminated to ≥52% and those of S.nemoralisto ≥19/, regardless of when they were exhumed. Timson's index, which integrates percentages, rates and times for onset of germination, was higher at all temperature regimes for Seeds exhumed in April 1995 than for those exhumed in September 1995. Freshly-matured Seeds of the three species germinated to 0–11% in darkness. Furthermore, regardless of when they were exhumed, Seeds ofS. altissimaandS. nemoralisincubated in darkness germinated mostly to only 0–9% over the range of temperature regimes. In contrast, ≤88% and ≤6% of the Seeds ofS. shortiiexhumed and incubated in darkness each April and September of 1993–96, respectively, germinated, ≤1% of them germinating while Buried in soil. Thus, although Buried Seeds of all three species exhibited an annual conditional dormancy/non-dormancy cycle, only those ofS. shortiiexhibited cyclic changes in their germination response in darkness.
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effect of flooding on annual dormancy cycles in Buried Seeds of two wetland carex species
Wetlands, 1996Co-Authors: Carol C. Baskin, Edward W. Chester, Jerry M. BaskinAbstract:Buried Seeds ofCarex comosa andC. sticta were exposed to nonflooded and flooded conditions and natural seasonal temperature changes for 30.5 and 33 mo, respectively. At 1-, 2- or 6-mo intervals, exhumed Seeds were tested for germination in light and darkness over a range of daily thermoperiods. Freshly-matured Seeds of both species were conditionally dormant; maximum germination was at 35/20°C, in light. Dormancy decreased in nonflooded and flooded Seeds ofC. comosa during late autumn and winter, but the decrease was greater in flooded than in nonflooded Seeds. Nonflooded and flooded Seeds ofC. stricta gained the ability to germinate in light during the first summer of burial and in darkness during the following winter. Seeds of neither species germinated while they were Buried in pots of soil under either nonflooded or flooded conditions in the nonheated greenhouse. Nonflooded and flooded Seeds of both species incubated in light and flooded Seeds ofC. comosa incubated in darkness had an annual conditional dormancy/nondormancy cycle, being conditionally dormant in summer and autumn and nondormant in spring. However, nonflooded Seeds ofC. comosa incubated in darkness remained dormant, germinating to only 1%. Most nonflooded and flooded Seeds ofC. stricta incubated in darkness had an annual dormancy/nondormancy cycle, being dormant in summer and nondormant in spring. Thus, flooding influenced the annual changes in dormancy states of Buried Seeds ofC. comosa, but it had no effect on Seeds ofC. stricta.
Roberto L. Benech-arnold - One of the best experts on this subject based on the ideXlab platform.
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The role of seed water content for the perception of temperature signals that drive dormancy changes in Polygonum aviculare Buried Seeds.
Functional plant biology : FPB, 2020Co-Authors: Cristian Malavert, Diego Batlla, Roberto L. Benech-arnoldAbstract:Seedling emergence in the field is strongly related to the dynamics of dormancy release and induction of the seed bank, which is mainly regulated by soil temperature. However, there is limited information on how temperature-driven effects on dormancy changes are modulated by the seed hydration-level. We investigated the effect of seed water content (SWC) on the dormancy release and dormancy induction in Polygonum aviculare L. Seeds. We characterised quantitatively the interaction between seed water content (SWC) and temperature through the measurement of changes in the lower limit temperature for seed germination (Tl) during dormancy changes for Seeds with different SWC. These relationships were inserted in existing population-based threshold models and were run against field obtained data. The model considering SWC was able to predict P. aviculare field emergence patterns. However, failure to consider SWC led to overestimations in the emergence size and timing. Our results show that in humid temperate habitats, the occurrence of eventual water shortages during late-winter or spring (i.e. short periods of water content below 31% SWC) can affect soil temperature effects on seed dormancy, and might lead reductions in the emergence size rather than to significant temporal displacements in the emergence window. In conclusion, SWC plays an important role for the perception of temperature signals that drive dormancy changes in Buried Seeds.
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The role of fluctuations in soil water content on the regulation of dormancy changes in Buried Seeds of Polygonum aviculare L.
Seed Science Research, 2006Co-Authors: Diego Batlla, Roberto L. Benech-arnoldAbstract:It has been hypothesized that fluctuations in soil water content may affect the dormancy status of weed seed banks under field conditions. In this paper, we present results showing that fluctuations in soil water content affect the dormancy status of Buried Seeds of Polygonum aviculare L. stored at dormancy-releasing temperatures. Effects of fluctuations in soil water content on the dormancy status of P. aviculare Seeds were evaluated by comparing changes in the range of temperatures and water potentials permissive for germination, and in the sensitivity to fluctuating temperatures, between Seeds subjected to a moist soil regime (MS) or to a fluctuating soil water content regime (FS). In comparison to the dormancy release pattern observed for Seeds subjected to MS, Seeds subjected to FS generally showed an increase in their dormancy level after periods of storage under dry soil conditions, and a decrease in their dormancy level after periods of storage under moist soil conditions. These effects were more pronounced during early stages of the storage period, producing larger changes in the thermal and water potential range for seed germination than in the sensitivity of Seeds to fluctuating temperatures. Seeds subjected to FS generally exhibited a lower mean low-limit temperature, lower mean thermal time and hydrotime requirements for germination, and a higher proportion of the seed population with the capacity to germinate in situ, than Seeds subjected to MS. The results obtained suggested that fluctuations in soil water content could be an additional factor affecting dormancy and weed emergence patterns under field conditions.
Edward W. Chester - One of the best experts on this subject based on the ideXlab platform.
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Seasonal changes in the germination responses of Buried Seeds of three native eastern North American winter annuals
Plant Species Biology, 2003Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Long-term studies of seasonal changes in temperature and light : dark requirements for germination were conducted on Seeds of Plantago virginica (87 months), Silene antirrhina (32.5 months) and Triodanis perfoliata (36.5 months), Buried under natural temperature regimes in central Kentucky, USA. Seeds of P. virginica exhibited an annual conditional dormancy/non-dormancy cycle; thus, the species has the potential to behave as a facultative winter annual. Seeds of T. perfoliata and S. antirrhina had an annual dormancy/non-dormancy cycle, but dormancy induction was not completed until April or May. Thus, depending on the year, 3–21% and 1–97% of the S. antirrhina and T. perfoliata Seeds, respectively, germinated in March and these species also have the potential to behave as facultative winter annuals. Data from long-term Buried Seeds studies in central Kentucky are now available for 16 native (including the three species reported in this paper) and nine non-native winter annuals of eastern North America. Buried Seeds of non-natives, as well as those of natives whose geographic range extends beyond eastern North America, tend to have a conditional dormancy/non-dormancy cycle, while those of natives with a range restricted to eastern North America tend to have a dormancy/non-dormancy cycle. However, testing of this hypothesis will have to await data for more winter annuals so that a phylogenetically independent analysis can be conducted.
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Effect of Seasonal Temperature Changes on Germination Responses of Buried Seeds of Agalinis fasciculate (Scrophulariaceae), and a Comparison with 12 Other Summer Annuals Native to Eastern North America
Plant Species Biology, 1998Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:Seeds of Agalinis fasciculata, a native eastern North American summer annual, were dormant at maturity inautumn and thus did not germinate in light or in darkness at 12/12 hdaily temperatures of 15/6,20/10, 25/15,30/15 and 35/20°C.Buried Seeds exposed to natural temperature changes in Lexington, Kentucky (USA) for 53 months came out of dormancy in late autumn and winter and re-entered it in late spring and early summer of each year. Non-dormant Seeds germinated to 60–100% in light at 20/10°C. Stratification at 5°C broke dormancy, and nondormant Seeds entered dormancy during exposure to 25/15 or 30/15°C. Light was required for germination, but some Seeds could be light-stimulated during stratification. Seeds stratified in light had a broader temperature range for germination than those stratified in darkness and tested in light. Buried Seeds of 11 of the 12 previously-studied native eastern North American summer annuals exhibited seasonal changes intheir dormancy states. As Buried Seeds of the 12 species began to come out of dormancy during winter, they germinated only at high temperatures, but with additional stratification the minimum temperature for germination decreased, which is a Type 2 temperature response pattern. As Seeds of A. fasciculata began to come out of dormancy during stratification, they germinated at an intermediate temperature (20/10°C), but with additional stratification the maximum temperature for germination increased and the minimum temperature decreased, which is a Type 3 pattern. This is the first report of a Type 3pattern in a summer annual and in the Scrophulariaceae. However, the ecological significance, if any, of Type 3 in A. fasciculata Seeds is unknown and may reflect more about the past history of the species or its ancestors than it does about present-day ecological adaptations to the habitat.
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effect of flooding on annual dormancy cycles in Buried Seeds of two wetland carex species
Wetlands, 1996Co-Authors: Carol C. Baskin, Edward W. Chester, Jerry M. BaskinAbstract:Buried Seeds ofCarex comosa andC. sticta were exposed to nonflooded and flooded conditions and natural seasonal temperature changes for 30.5 and 33 mo, respectively. At 1-, 2- or 6-mo intervals, exhumed Seeds were tested for germination in light and darkness over a range of daily thermoperiods. Freshly-matured Seeds of both species were conditionally dormant; maximum germination was at 35/20°C, in light. Dormancy decreased in nonflooded and flooded Seeds ofC. comosa during late autumn and winter, but the decrease was greater in flooded than in nonflooded Seeds. Nonflooded and flooded Seeds ofC. stricta gained the ability to germinate in light during the first summer of burial and in darkness during the following winter. Seeds of neither species germinated while they were Buried in pots of soil under either nonflooded or flooded conditions in the nonheated greenhouse. Nonflooded and flooded Seeds of both species incubated in light and flooded Seeds ofC. comosa incubated in darkness had an annual conditional dormancy/nondormancy cycle, being conditionally dormant in summer and autumn and nondormant in spring. However, nonflooded Seeds ofC. comosa incubated in darkness remained dormant, germinating to only 1%. Most nonflooded and flooded Seeds ofC. stricta incubated in darkness had an annual dormancy/nondormancy cycle, being dormant in summer and nondormant in spring. Thus, flooding influenced the annual changes in dormancy states of Buried Seeds ofC. comosa, but it had no effect on Seeds ofC. stricta.
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Effect of flooding on annual dormancy cycles in Buried Seeds of two wetlandCarex species
Wetlands, 1996Co-Authors: Carol C. Baskin, Edward W. Chester, Jerry M. BaskinAbstract:Buried Seeds ofCarex comosa andC. sticta were exposed to nonflooded and flooded conditions and natural seasonal temperature changes for 30.5 and 33 mo, respectively. At 1-, 2- or 6-mo intervals, exhumed Seeds were tested for germination in light and darkness over a range of daily thermoperiods. Freshly-matured Seeds of both species were conditionally dormant; maximum germination was at 35/20°C, in light. Dormancy decreased in nonflooded and flooded Seeds ofC. comosa during late autumn and winter, but the decrease was greater in flooded than in nonflooded Seeds. Nonflooded and flooded Seeds ofC. stricta gained the ability to germinate in light during the first summer of burial and in darkness during the following winter. Seeds of neither species germinated while they were Buried in pots of soil under either nonflooded or flooded conditions in the nonheated greenhouse. Nonflooded and flooded Seeds of both species incubated in light and flooded Seeds ofC. comosa incubated in darkness had an annual conditional dormancy/nondormancy cycle, being conditionally dormant in summer and autumn and nondormant in spring. However, nonflooded Seeds ofC. comosa incubated in darkness remained dormant, germinating to only 1%. Most nonflooded and flooded Seeds ofC. stricta incubated in darkness had an annual dormancy/nondormancy cycle, being dormant in summer and nondormant in spring. Thus, flooding influenced the annual changes in dormancy states of Buried Seeds ofC. comosa, but it had no effect on Seeds ofC. stricta.
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Annual dormancy cycle and influence of flooding in Buried Seeds of mudflat populations of the summer annual Leucospora multifida
Écoscience, 1994Co-Authors: Carol C. Baskin, Jerry M. Baskin, Edward W. ChesterAbstract:AbstractDormant Seeds of Leucospora multifida (Michx) Nutt. were used to determine: (1) temperature requirements for loss of dormancy; (2) if Buried Seeds undergo seasonal changes in their dormancy states; and (3) effects of flooding on dormancy loss and induction. Seeds came out of dormancy when Buried at 5°C and 15/6°C for 12 weeks, but at 20/10°C, 25/15°C and 30/15°C, they gained the ability to germinate only at 30/15°C and 35/20°C. Seeds Buried in soil and exposed to natural seasonal temperature changes under non-flooded conditions exhibited an annual conditional dormancy/non-dormancy cycle, being non-dormant in spring and early summer, and conditionally dormant in late summer and autumn. Non-dormant Seeds required light for germination at all thermoperiods, and they did not germinate in light or darkness at 15/6°C. Flooding prevented non-dormant Seeds from entering conditional dormancy in summer, and it prevented dormant Seeds from coming out of dormancy in winter. However, if dormancy loss had start...
Hildie Maria E Nacorda - One of the best experts on this subject based on the ideXlab platform.
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sexual reproduction in se asian seagrasses the absence of a seed bank in thalassia hemprichii
Aquatic Botany, 2003Co-Authors: Rene N Rollon, Hildie Maria E Nacorda, Jan E VermaatAbstract:Abstract We report the absence of a persistent seed bank in Thalassia hemprichii in NW Philippine seagrass beds. The survival of Buried Seeds was assessed experimentally since such a capacity is a prerequisite for the formation of seed bank. We found a rapid germination of non-dormant Seeds and development into seedlings. Such seedlings could not survive under Buried conditions (5 and 10 cm) for longer than a week.
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short communication sexual reproduction in se asian seagrasses the absence of a seed bank in thalassia hemprichii
2003Co-Authors: Rene N Rollon, Jan E Vermaat, Hildie Maria E NacordaAbstract:We report the absence of a persistent seed bank in Thalassia hemprichii in NW Philippine seagrass beds. The survival of Buried Seeds was assessed experimentally since such a capacity is a prerequisite for the formation of seed bank. We found a rapid germination of non-dormant Seeds and development into seedlings. Such seedlings could not survive under Buried conditions (5 and 10 cm) for longer than a week. © 2002 Elsevier Science B.V. All rights reserved.
