TITLE:
Morphological Response of Jack Pine to the Interactive Effects of Carbon Dioxide, Soil Temperature and Photoperiod
AUTHORS:
Md. Shah Newaz, Qing-Lai Dang, Rongzhou Man
KEYWORDS:
Tree Seedling Physiology, Plant Ecophysiology, Tree Migration, Climate Change, Boreal Forest
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.7 No.6,
April
26,
2016
ABSTRACT: Responding to the
predicted shift in climate envelope jack pine, (Pinus banksiana Lamb.) might migrate 10° northward between
2071 and 2100 and will be exposed to a different photoperiod regime. Successful
migration of the species might depend on the initial acclimating capability to
the conditions of new location. The impacts of elevated carbon dioxide concentration
[CO2], soil temperature and photoperiod on the phenological traits,
growth and biomass responses in jack pine seedlings were investigated.
Seedlings were grown in greenhouses under two [CO2] (400 and 950
μmol•mol-1), two soil temperatures (ambient soil temperature at seed
origin and 5°C warmer) and three photoperiod regimes (photoperiods at
seed origin, 5° north of the seed origin and 10° north of the
seed origin). Budburst and bud setting time were recorded and the seedling
height (Ht), root collar diameter (RCD), root biomass, stem biomass and leaf
biomass were measured after six months of treatment. It was observed that under
elevated [CO2], ambient Tsoil and photoperiods associated
with 10° northward migrations budburstis advanced by 10 days. Photoperiods
toward north significantly prolonged the bud setting time. However, tri-factor
interactive effect on bud set was not statistically significant. Elevated [CO2]
significantly (P 2] significantly
increased the projected leaf area, it had no significant effect on specific
leaf area. Elevated [CO2] significantly reduced the shoot to root
ratio, which indicated higher biomass allocation in roots under elevated [CO2].
However, all these growth and biomass responses were statistically
insignificant under tri-factor interactive effects. The results suggest that
climate change induced northward migration will not affect the growth of jack
pine. However, a long distance migration (e.g. 10° north) will expose
the species to late-spring frost damage.