| In order to understand the relations between photosynthesis parameters and its influencing factors
of different geographical populations of Polygonatum kingianum .The photosynthetic day changes of of three different
geographical populations of P. kingianum were measured by LI-6400XT portable photosynthetic system under
natural condition ,which provides a basis for breeding and cultivation. The results showed that the curves of Pn diurnal
variation of the three provenances were different.The daily variation of Pn in provenance of Yongde Yunnan was single
peak curve with obvious midday decrease in photosynthesis,but the other two provenances were presented as doublepeak
curves. The stomatal conductance (Gs) and transpiration rate (Tr) of the three provenances were presented as
double-peak curves,the daily variation of intercellular CO2 concentration(Ci) and water use efficiency(WUE) were
irregular.There were differences in photosynthetic characteristics among the three provenances,the rank of Pn average from big to small was Yongde Yunnan,Huili Sichuan and Jinping Yunnan. The photosynthetic parameters showed
a large decline except the Tr of Yongde Yunnan in the afternoon.Correlation analysis demonstrated that there was a
significant positive correlation between Pn and Gs in provenance of Yongde Yunnan,a significant positive correlation
between Pn ,Gs and Tr in provenance of Jinping Yunnan,and was a significant positive correlation between Pn, Gs, Tr
and air relative humidity (RH) and a significant negative correlation with atmospheric temperature (Ta) in provenance
of Huili Sichuan. In addition,there was a significant positive correlation between Gs and RH of three provenances, and
Pn and Gs of all provenances showed a significant positive correlation. Therefore, RH was the main influencing factor
on Pn of three provenances. There were obvious differences in the photosynthetic daily process of three geographical
populations of Polygonatum kingianum. It showed that there was a great difference in the adaptability of different
populations to the same environment. This difference would be considered when introducing and cultivating. |
