[Acclimation of foliar photosynthetic apparatus of three tropical woody species to growth irradiance].
The photosynthetic characteristics and protective role of leaf antioxidant systems were studied for seedlings of three woody species, Anthocephalus chinensis, Barringtonia pendala, Garcinia hanburyi, acclimated to 8%, 25%, 50% of natural sunlight for four months. As growth irradiance increased, the saturation points, the light compensation points of photosynthesis, the maximum net photosynthetic rate, and the non-photochemical quenching efficiency of three species were increased, while the apparent quantum yield (AQY), the effective quantum efficiency (Fv'/Fm'), and the photochemical quenching efficiency (qP) were decreased. In protective enzymes systems, SOD and APX activities increased with increasing growth irradiance, but CAT activity was not consistent with PFD. AsA exhibited the most dramatic increase in response to growth irradiance. It could be concluded that besides the increase in xanthophyll cycle-dependent energy dissipation, the enhancement of leaf antioxidants was also a protective pathway against high light intensity.
Cai
Zhiquan
Z
Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, China. czq@xtbg.org.cn
Cao
Kunfang
K
Feng
Yulong
Y
Feng
Zhili
Z
D000064:Acclimatization; D001205:Ascorbic Acid / Q000032:analysis; D002374:Catalase / Q000378:metabolism; D019610:Cytoprotection; D010788:Photosynthesis; D013472:Sunlight; D013482:Superoxide Dismutase / Q000378:metabolism; D014197:Trees / Q000254:growth & development / Q000378:metabolism*
D002374:Catalase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid