Abstract: Taking 5 breeding lines tea as test material, the leaf functional and photosynthetic characteristics of the leaves at different positions were monitored, and correlations between the leaf functional and photosynthetic characteristic analyzed. The leaf functional characteristic included leaf area (LA), the leaf index(LI), specific leaf area (SLA), leaf dry matter content(LDMC), Chla, Chlb, Chl and Car, the photosynthetic indexes included net photosynthetic rate(P_n), stomatal conductance(G_s), intercellular CO₂ concentration(C_i) and transpiration rate(T_r). The results showed that the LA, LMDC, P_n, G_s and T_r firstly increased and then decreased with the leaf position went up, whose maximum value emerged at the middle leaves(from 3rd to 4th). The 1 and 6 leaf measurements were substantially below other leaf position (P<0.05). The LI and SLA increased with the elevation of the leaf position, the maximum values of SLA was at 6th leaf (P<0.05). The Chla, Chlb and Chl of different position leaves (from 1st to 4th) were relatively high, and their amounts in leaves of the 6th leaf were usually lower than other leaf position (P<0.05). The variation trend of Car was not obvious with the leaf position went up. The correlation analysis indicated that the LA was significant and remarkably significant positive correlated with LI, LDMC, Chla, Chlb, Chl and Car, but significant negative with C_i, and not significant correlation with other indicators. LI had no significant correlation with other indicators (except LA). The SLA and LDMC, Chla, Chlb, Chl, Car were significant and remarkably significant negative correlation with P_n, but significant positive correlation with C_i, and not significant correlation with other indicators. The LDMC was significant and remarkably significant positive correlation with L Chla, Chl and P_n. The Chla, Chlb, Chl and Car were positively correlated with each other significantly, and the photosynthetic pigments were remarkably significant positive correlated with Pn. The G_s and T_r showed no significant correlation with other indicators. Our results suggest that: the LA, photosynthetic capacity and LDMC of middle leaves of (from 3rd to 4th) tea plants were relatively higher than those of other leaf positions, so the middle leaves should be the experimental material to test photosynthetic; SLA, LDMC and photosynthetic pigments were closely related with P_n, so they could be used as an index to evaluate the photosynthetic capacity.

Key words: tea plant, different leaves positions, leaf functional, leaf photosynthetic