[Effects of shading on photosynthetic characteristics of Pinellia ternata leaves].
OBJECTIVE
To study the effects of shading on photosynthetic physiology and chlorophyll fluorescence of Pinellia ternata.


METHODS
Plant growth, chlorophyll content, net photosynthetic rate (P(n)) and chlorophyll fluorescence in P. ternata were investigated under different shading treatments (0%, 70% and 90%) when it grew about 15 cm high.


RESULTS
The results showed that fresh weight of a tuber, height, leaf length, width, leaf area, specific leaf area (SLA) and contents of chlorophyll content were enhanced after shaded, and chlorophyll a/b rate declined. Compared with control, net photosynthetic rate, light compensation point (LCP) and light saturation point (LSP) of P. ternata decreased after shading, but apparent quantum yield (AQY) increased; quantum yield of PS II (PhiPS II), minimal fluorescence (F(o)), maximal fluorescence (F(m)), intrinsic photochemical efficiency of PS II (F(v)/F(m)) and photochemical quenching coefficient (qP) were enhanced.


CONCLUSIONS
Compared with control, all data indicated that there were distinctive differences between the height, SLA, chlorophyll content, P(n) and chlorophyll fluorescence characteristics under the shading treatments (70% and 90%), the fresh weight of a tuber increased after 70% shading, and provided better environmental conditions for the growth of P. ternata.
Xue
Jian-Ping
JP
Anhui Key Laboratory of Plant Resources and School of Life Science, Huaibei Coal Industry Teachers' College, Huaibei 235000, China. xuejp2000@yahoo.com.cn
Wang
Xing
X
Zhang
Ai-Min
AM
Huang
Xun-Duan
XD
He
Jia-Qing
JQ
Chang
Li
L
D002734:Chlorophyll / Q000378:metabolism; D008027:Light; D010788:Photosynthesis / Q000187:drug effects*; D030021:Pinellia / Q000378:metabolism / Q000528:radiation effects*; D018515:Plant Leaves / Q000378:metabolism / Q000528:radiation effects*
D002734:Chlorophyll