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Winter cold-tolerance thresholds in field-grown Miscanthus hybrid rhizomes.

Peixoto Mde M, Friesen PC, Sage RF - J. Exp. Bot. (2015)

Bottom Line: Two artificial freezing protocols were tested: one lowered the temperature continuously by 1°C h(-1) to the treatment temperature and another lowered the temperature in stages of 24h each to the treatment temperature.The results demonstrated that rhizomes from diploid Miscanthus lines have superior cold tolerance that could be exploited to improve performance in more productive polyploid lines.With expected levels of soil insulation, low winter air temperatures should not harm rhizomes of tolerant diploid genotypes of Miscanthus in temperate to sub-boreal climates (up to 60°N); however, the observed winter cold in sub-boreal climates could harm rhizomes of existing polyploid varieties of Miscanthus and thus reduce stand performance.

View Article: PubMed Central - PubMed

Affiliation: University of Toronto, Department of Ecology and Evolutionary Biology, 25 Willcocks Street, Toronto, Ontario, Canada M5S3B2.

No MeSH data available.


Related in: MedlinePlus

The location of 73 Environment Canada weather stations where soil temperature at a 5cm depth was recorded between 1984 and 2006. Green circles indicate weather stations where the minimal soil temperature was above –6.4 ° C, yellow circles indicate weather stations with minimal temperatures between –6.4 and –14.1 °C, and red circles indicate weather stations with minimal temperature below –14.1 °C (Environment Canada 2014; http://weather.gc.ca/). Weather stations with 5 years or less of recorded data are marked with a ‘*’. See online Supplemental Table S.1 for additional information, including the number of years recorded.
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Figure 2: The location of 73 Environment Canada weather stations where soil temperature at a 5cm depth was recorded between 1984 and 2006. Green circles indicate weather stations where the minimal soil temperature was above –6.4 ° C, yellow circles indicate weather stations with minimal temperatures between –6.4 and –14.1 °C, and red circles indicate weather stations with minimal temperature below –14.1 °C (Environment Canada 2014; http://weather.gc.ca/). Weather stations with 5 years or less of recorded data are marked with a ‘*’. See online Supplemental Table S.1 for additional information, including the number of years recorded.

Mentions: The air temperature at the Leamington, Ontario, field site decreased to –14 °C on 17 December 2009 and to –20 °C on 10 January 2010 (Fig. 1A). The soil temperature fell to the seasonal low on 3 January 2010; at 1cm below ground, soil temperature was –4 °C, while at a 7cm depth, it was –1 °C. These soil temperatures followed a warm spell in the previous week that melted the snow cover and in doing so reduced its insulation. Shortly after the observed low, new snow accumulated and the soil temperature returned to near –1 °C for the remainder of the winter. In the 2010–2011 dormant season, the coldest soil temperature recorded was –4 °C on 24 January 2011 at a 1cm depth, when the minimal air temperature fell to –15 °C and only traces of snow were present on the ground (Environment Canada 2014, http://weather.gc.ca/; Fig. 1B). The temperature database of Environment Canada 2014 (Supplementary Table S1) showed that in southern Ontario, southern British Columbia, southern Quebec, and southeast Labrador, most weather stations did not record a soil temperature below –6.5 °C at a 5cm depth between 1984 and 2006 (Fig. 2). During the same period, most stations in southwest Quebec, Nova Scotia, Alberta, the southern Yukon, and southern Northwest Territories recorded a minimum soil temperature at a 5cm depth of between –6.5 and –14 °C. Weather stations in Saskatchewan, southern Manitoba, New Brunswick, northern and eastern Quebec, western Labrador, and Nunavut recorded soil temperatures below –14 °C at a 5cm depth.


Winter cold-tolerance thresholds in field-grown Miscanthus hybrid rhizomes.

Peixoto Mde M, Friesen PC, Sage RF - J. Exp. Bot. (2015)

The location of 73 Environment Canada weather stations where soil temperature at a 5cm depth was recorded between 1984 and 2006. Green circles indicate weather stations where the minimal soil temperature was above –6.4 ° C, yellow circles indicate weather stations with minimal temperatures between –6.4 and –14.1 °C, and red circles indicate weather stations with minimal temperature below –14.1 °C (Environment Canada 2014; http://weather.gc.ca/). Weather stations with 5 years or less of recorded data are marked with a ‘*’. See online Supplemental Table S.1 for additional information, including the number of years recorded.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4493781&req=5

Figure 2: The location of 73 Environment Canada weather stations where soil temperature at a 5cm depth was recorded between 1984 and 2006. Green circles indicate weather stations where the minimal soil temperature was above –6.4 ° C, yellow circles indicate weather stations with minimal temperatures between –6.4 and –14.1 °C, and red circles indicate weather stations with minimal temperature below –14.1 °C (Environment Canada 2014; http://weather.gc.ca/). Weather stations with 5 years or less of recorded data are marked with a ‘*’. See online Supplemental Table S.1 for additional information, including the number of years recorded.
Mentions: The air temperature at the Leamington, Ontario, field site decreased to –14 °C on 17 December 2009 and to –20 °C on 10 January 2010 (Fig. 1A). The soil temperature fell to the seasonal low on 3 January 2010; at 1cm below ground, soil temperature was –4 °C, while at a 7cm depth, it was –1 °C. These soil temperatures followed a warm spell in the previous week that melted the snow cover and in doing so reduced its insulation. Shortly after the observed low, new snow accumulated and the soil temperature returned to near –1 °C for the remainder of the winter. In the 2010–2011 dormant season, the coldest soil temperature recorded was –4 °C on 24 January 2011 at a 1cm depth, when the minimal air temperature fell to –15 °C and only traces of snow were present on the ground (Environment Canada 2014, http://weather.gc.ca/; Fig. 1B). The temperature database of Environment Canada 2014 (Supplementary Table S1) showed that in southern Ontario, southern British Columbia, southern Quebec, and southeast Labrador, most weather stations did not record a soil temperature below –6.5 °C at a 5cm depth between 1984 and 2006 (Fig. 2). During the same period, most stations in southwest Quebec, Nova Scotia, Alberta, the southern Yukon, and southern Northwest Territories recorded a minimum soil temperature at a 5cm depth of between –6.5 and –14 °C. Weather stations in Saskatchewan, southern Manitoba, New Brunswick, northern and eastern Quebec, western Labrador, and Nunavut recorded soil temperatures below –14 °C at a 5cm depth.

Bottom Line: Two artificial freezing protocols were tested: one lowered the temperature continuously by 1°C h(-1) to the treatment temperature and another lowered the temperature in stages of 24h each to the treatment temperature.The results demonstrated that rhizomes from diploid Miscanthus lines have superior cold tolerance that could be exploited to improve performance in more productive polyploid lines.With expected levels of soil insulation, low winter air temperatures should not harm rhizomes of tolerant diploid genotypes of Miscanthus in temperate to sub-boreal climates (up to 60°N); however, the observed winter cold in sub-boreal climates could harm rhizomes of existing polyploid varieties of Miscanthus and thus reduce stand performance.

View Article: PubMed Central - PubMed

Affiliation: University of Toronto, Department of Ecology and Evolutionary Biology, 25 Willcocks Street, Toronto, Ontario, Canada M5S3B2.

No MeSH data available.


Related in: MedlinePlus