TITLE:
Developmental Changes of the Photochemical Reflectance Index (PRI), Chlorophyll Fluorescence and Leaf Pigments Show the Adaptability of Trees to Local Environments
AUTHORS:
Hokyung Baek, Unhaing Cho
KEYWORDS:
Photochemical Reflectance Index, Chlorophyll Fluorescence, Chlorophyll, Flavonoid
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.8 No.1,
December
31,
2016
ABSTRACT: For plants growing in parks and along the roadsides of a city, the environmental
and seasonal regulation of growth, or photosynthesis, is seldom assessed.
The phenology of plants may differ due to varying environments,
which may result in different growth or adaptability to local environments.
Therefore, we explored several assays and optical indicators of photosynthesis
and stress in three tree species (Prunus yedoensis Matsum, Zelkova serrata Makino and Acer palmatum Thunb. ) and two herbaceous species (Artemisia princeps Pamp and Taraxacum officinale Weber)growing commonly in three
local parks of Changwon city, a large industrial city in Korea. The photochemical
reflectance index (PRI), chlorophyll fluorescence, and pigments including
chlorophyll and the flavonoids of leaves were monitored over a growing
season for two years to evaluate the adaptability of plants to local environments.
The values of all measurements exhibited striking seasonal and regional
changes. PRI values were closely timed with photosynthetic activity and
the pigment formation of leaves, particularly in some tree species. For the tree
species, the plants which had the low values of PRI during the active growing
season showed low levels of both chlorophyll fluorescence and high level of
flavonoid, indicating that these plants were experiencing low photosynthetic
activity and the specific needs in growth and development were not sufficiently
provided by the local environment. Our results indicate that PRI provided
a clear optical indicator of plant adaptability to the local environment
and may provide a useful metric of effective growth using remote sensing
measurements. Furthermore, the periodic PRI measurement is encouraged to
be included in the surveillance program for city plant management.