Relational analysis of leaf characteristics and photosynthetic capacities of plants
植物叶片特征与光合性能的关系

Southeast-facing matured leaves of five plants Viburnum odoratissimum (VO), Ginkgo biloba (GB), Oxalis triangularis cv Purpurea (OTP), Ficus elastica cv. Decora Burgundyi (FEDB) and Morus alba (MA)] were used to determine the characteristics and photosynthetic capacities of plant leaves in sunny days. The Li-Cor 6400 Portable Photosynthesis Measuring System, Modulated Chlorophyll Fluorescence System (IMAGING-PAM M-Series), Dual-PAM-100 Measuring System and conventional methods were used to analyze the relationships among leaf characteristics and photosynthetic capacities. The results showed significant differences (P < 0.05 or P < 0.01) in leaf characteristics and photosynthetic capacities among different plants. Differences in specific leaf dry weight 35~215 g (DW)·m-2] among plants were higher than those in specific leaf fresh weight 0.28~1.04 kg (FW)·m-2]. Leaf chloroplast pigment contents chlorophyll a (Chla), chlorophyll b (Chlb), total chlorophyll (Chl) and carotenoid (Xc)] of MA and VO were the highest, followed by GB and FEDB and those of OTP were the lowest. While anthocyanin (Ant) content of OTP was maximum for 0.122 mg·g-1(FW) and 0.488 mg·g-1(DW), those of the others plants were low and similar. While OTP leaf Chla/Chlb (6.27), MA leaf Chl/Xc (9.97), MA leaf Chl/Ant (43.81) and VO leaf Xc/Ant (7.17) were the highest, OTP leaf Chl/Ant (0.49) and Xc/Ant (2.46) were the lowest. The orders of stomata conduction, transpiration rate, intercellular CO2 concentration and net photosynthetic rate (Pn) of the plants were MA > GB > OTP > VO > FEDB. MA and VO leaf practical quantum PSII Y(II)] was the highest and that of GB was low. Although MA, OTP and FEDB PSI were high, MA and FEDB PSI photo-protection was weak and that of OTP strong. Correlation analysis indicated that the effects of Ant and Xc on Pn were insignificant. Also stomata characteristics and chlorophyll content positively regulated P>/i>n. Y(II) mainly depended on chloroplast pigment content (especially Chla) and the relationship between Y(I) and Chl/Xc was positive. Leaf stomata opening and chlorophyll content negatively regulated PSII and PSI photo-protection. It, however, positively regulated PSII photo-damage. The effect of Xc was the exact reverse of that of Chl.