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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 survivability of rhizomes as a function of relative conductivity in the staged-cooling experiment. (A) M115; (B) M147; (C) M1; (D) M119. Symbols represent the observed mean±SE (n=6), and lines represent the predicted values fitted using a logistic regression. Differences in collection time were not significant (P=0.99), while genotypes showed different LEL50 values (P<0.001). The post-hoc Tukey test indicated that the diploid genotypes shared a common LEL50 (Pz=0.82), as did M1 and M119 (Pz=0.99). However the LEL50 for M115 and M147 were different from that of M1 and M119 (Pz<0.001).
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Figure 7: The survivability of rhizomes as a function of relative conductivity in the staged-cooling experiment. (A) M115; (B) M147; (C) M1; (D) M119. Symbols represent the observed mean±SE (n=6), and lines represent the predicted values fitted using a logistic regression. Differences in collection time were not significant (P=0.99), while genotypes showed different LEL50 values (P<0.001). The post-hoc Tukey test indicated that the diploid genotypes shared a common LEL50 (Pz=0.82), as did M1 and M119 (Pz=0.99). However the LEL50 for M115 and M147 were different from that of M1 and M119 (Pz<0.001).

Mentions: The diploid genotypes also exhibited higher LEL50 values (30% for M115 and 27% for M147; Fig. 7A, B) in comparison with the continuous-cooling rate experiment, and with M1 and M119 (18 and 17%, respectively; Fig. 7C, D). For the staged-cooling experiment, the LEL50 of the diploid genotypes was reached at lower temperatures than at the continuous-cooling rate, and complete leakage was not reached even after treatment at –22 °C (Fig. 8A, B). For the allopolyploids, there was little difference in the relationship between temperature treatment and relative conductivity, and at –22 °C the rhizomes had nearly complete leakage (Fig. 8C, D).


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

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

The survivability of rhizomes as a function of relative conductivity in the staged-cooling experiment. (A) M115; (B) M147; (C) M1; (D) M119. Symbols represent the observed mean±SE (n=6), and lines represent the predicted values fitted using a logistic regression. Differences in collection time were not significant (P=0.99), while genotypes showed different LEL50 values (P<0.001). The post-hoc Tukey test indicated that the diploid genotypes shared a common LEL50 (Pz=0.82), as did M1 and M119 (Pz=0.99). However the LEL50 for M115 and M147 were different from that of M1 and M119 (Pz<0.001).
© Copyright Policy - creative-commons
Related In: Results  -  Collection

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

Figure 7: The survivability of rhizomes as a function of relative conductivity in the staged-cooling experiment. (A) M115; (B) M147; (C) M1; (D) M119. Symbols represent the observed mean±SE (n=6), and lines represent the predicted values fitted using a logistic regression. Differences in collection time were not significant (P=0.99), while genotypes showed different LEL50 values (P<0.001). The post-hoc Tukey test indicated that the diploid genotypes shared a common LEL50 (Pz=0.82), as did M1 and M119 (Pz=0.99). However the LEL50 for M115 and M147 were different from that of M1 and M119 (Pz<0.001).
Mentions: The diploid genotypes also exhibited higher LEL50 values (30% for M115 and 27% for M147; Fig. 7A, B) in comparison with the continuous-cooling rate experiment, and with M1 and M119 (18 and 17%, respectively; Fig. 7C, D). For the staged-cooling experiment, the LEL50 of the diploid genotypes was reached at lower temperatures than at the continuous-cooling rate, and complete leakage was not reached even after treatment at –22 °C (Fig. 8A, B). For the allopolyploids, there was little difference in the relationship between temperature treatment and relative conductivity, and at –22 °C the rhizomes had nearly complete leakage (Fig. 8C, D).

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