Development of height growth and frost hardiness for one-year-old Norway spruce seedlings in greenhouse conditions in response to elevated temperature and atmospheric CO₂ concentration

Abstract

Development of height growth and frost hardiness for one-year-old Norway spruce seedlings in greenhouse conditions in response to elevated temperature and atmospheric CO 2 concentrationLevkoev E., Mehtätalo L., Luostarinen K., Pulkkinen P., Zhigunov A., Peltola H. (2018). Development of height growth and frost hardiness for one-year-old Norway spruce seedlings in greenhouse conditions in response to elevated temperature and atmospheric CO 2 concentration. Silva Fennica vol. 52 no. 3 article id 9980. 15 p. https://doi.org/10.14214/sf.9980 Highlights• Elevated temperature resulted in increased height growth, delayed onset and shortened duration of autumn frost hardiness development in Norway spruce seedlings. • Elevated temperature increased variation between genotypes in height growth and frost hardiness development. • Elevated atmospheric CO 2 concentration had no effect on the development of height or autumn frost hardiness in Norway spruce seedlings. AbstractThe mean temperature during the potential growing season (April-September) may increase by 1 °C by 2030, and by 4 °C, or even more, by 2100, accompanied by an increase in atmospheric CO 2 concentrations of 536-807 ppm, compared to the current climate of 1981-2010, in which atmospheric CO 2 is at about 350 ppm. This may affect both the growth and frost hardiness of boreal trees. In this work, we studied the responses of height and autumn frost hardiness development in 22 half-sib genotypes of one-year-old Norway spruce (Picea abies (L.) Karst.) seedlings to elevated temperatures and atmospheric CO 2 concentration under greenhouse conditions. The three climate treatments used were: T+1 °C above ambient and ambient CO 2 ; T+4 °C above ambient and ambient CO 2 ; and T+4 °C above ambient and elevated CO 2 (700 ppm). The height growth rate and final height were both higher under T+4 °C compared to T+1 °C. Temperature increase also delayed the onset, and shortened the duration, of autumn frost hardiness development. Elevated CO 2 did not affect the development of height or frost hardiness, when compared to the results without CO 2 elevation under the same temperature treatment. Higher temperatures resulted in greater variation in height and frost hardiness development among genotypes. Three genotypes with different genetic backgrounds showed superior height growth, regardless of climate treatment; however, none showed a superior development of autumn frost hardiness. In future studies, clonal or full-sib genetic material should be used to study the details of autumn frost hardiness development among different genotypes.

Duration Limits on Field Storage in Closed Cardboard Boxes before Planting of Norway Spruce and Scots Pine Container Seedlings in Different Planting Seasons

“…In September, the seedlings with healthy needles were capable of hardening with decreasing air temperatures between the box opening and the freezing tests. The increased temperatures inside the boxes may also have delayed FH development, because elevated temperatures can delay the onset of FH in Norway spruce seedlings [45].…”

Comparison of deacclimation and reacclimation of silver birch, Norway spruce and Scots pine seedlings during winter warm and cold spells in Nordic boreal conditions

“…To our knowledge, there have been no studies of the responses of different genotypes of either Scots pine or Norway spruce to fluctuating winter temperatures. However, it has been observed that autumn frost hardening of one-year-old Norway spruce seedlings varies between genotypes when growing season temperatures increase (Levkoev et al 2018). In addition, the two-year-old seedlings received a short day treatment in July, but the one-year-old seedlings did not, which may have led to differences in responses to acclimation treatments.…”

The effects of planting practices and growing environment on the early performance of boreal tree seedlings

“…This may be one reason for the reduced FH in the box-stored seedlings in early August. In addition, temperatures were higher inside the boxes (Study I: Figure 2), which may have delayed the development of FH in Norway spruce seedlings (Levkoev et al 2018). Also, the lowered photosynthetic capacity of the seedlings stored in boxes over a week indicates a reduction in FH since it is dependent on the current photosynthates available (van den Driessche 1970).…”