| The changes of growth characters, photosynthetic characteristics, chlorophyll fluorescence parameters and biochemical indexes of six ground-cover plants including Aspidistra elatior'Punctata',Reineckia carnea, Hemerocallis×hybrida'Stella deoro', Liriope muscari'Variegata', Hosta×hybrida'So Sweet'and Speirantha gardenii were studied with four different shading treatments (0, 50%, 75%, 90% sun-shading) in this paper. The results showed that:(1)Shading treatments have obvious effects on the morphological indexes of six plants. With the increasing of sun-shading, the data of length, width and numbers of leaves of Aspidistra elatior'Punctata', Reineckia carnea and Speirantha gardenii increased and achieved the remarkable level compared to the control (P<0.05). The morphological indexes of three plants were the biggest in shading 90%. The morphological indexes of Hosta×hybrida'So Sweet'were the biggest in shading 75%. The data of length and width of Hemerocallis×hybrida'Stella deoro'and Liriope muscari'Variegata'were the biggest in shading 90%, but the numbers of leaves of two plants were the most in shading 50%.(2)The changes of chlorophyll content of six plants took the same trend in shading treatments. With the increasing of sun-shading, The contents of Chl.a, Chl.b and Chl.(a+b) in the leaves of six plants in shading treatments were significantly higher than the contents of the control (P<0.05) and were the biggest in shading 90%. The Chl.a/Chl.b took the trend of decreasing and were the smallest in shading 90%.(3)The LCP and LSP of six plants decreased with the increasing of sun-shading and reached the remarkable level compared to the control (P<0.05). In shding 90%, the LCP of Speirantha gardenii was the lowest (3.434μmol·m-2·s-1) and of Liriope muscari'Variegata'was the highest (8.104μmol·m-2·s-1). The AQY of Aspidistra elatior'Punctata',Reineckia carnea, Hosta×hybrida'So Sweet'and Speirantha gardenia were higher than that of control and biggest in shading 75% except Reineckia carnea. The AQY of three plants above were 0.0518, 0.0485 and 0.0528. The AQY of Reineckia carnea was biggest in shading 75% (0.0503) and that of Hemerocallis×hybrida'Stella deoro', Liriope muscari'Variegata'were biggest in shading 50%. The AQY of two plants above in shading 75% and 90% were lower than that of the control.(4)The Fv/Fm, Fv/Fo and Fv'/Fm of six plants showed the tendency of rising but the qN was opposite. The Fv/Fm, Fv/Fo and Fv'/Fm of Hemerocallis×hybrida'Stella deoro', Liriope muscari'Variegata'and Hosta×hybrida'So Sweet'had a few changes in shading treatments and there were the smallest in the control. The Fv/Fm of Aspidistra elatior'Punctata'and Speirantha gardenia were both less than 0.7 and the two plants appeared the phenomenon of light repression. The qN of Aspidistra elatior'Punctata', Reineckia carnea and Speirantha gardenii were relative higher and that of Hemerocallis×hybrida'Stella deoro', Liriope muscari'Variegata'and Hosta×hybrida'So Sweet'were relative lower.(5)The content of MDA of six plants showed the tendency of falling first and rising finally in general with the increasing of shading. The changes of SOD activities of Hosta×hybrida'So Sweet'took the trend of decreasing firstly and then increasing, while those of the other five plants took the trend of falling. POD activities of Speirantha gardenia and Hemerocallis×hybrida'Stella deoro'decreased in shading 50%, but obviously increased in shading 75% and then decreased. The changes of POD activities of the other four plants took the tendency of falling first and then rising.(6)Shading 75% and 90% were favourable to the growth of Aspidistra elatior'Punctata', Reineckia carnea and Speirantha gardenii and as to Hosta×hybrida'So Sweet'was 75%. 50% shading treatments was the most adaptive to the growth of Hemerocallis×hybrida'Stella deoro'and Liriope muscari'Variegata'. According to the comprehensive appraisal based on subordination function method, the shade tolerance of three plants was in the order: Speirantha gardenia>Aspidistra elatior var. variegate>Reineckia carnea>Hosta×hybrida'So Sweet'>Liriope muscari'Variegata'>Hemerocallis×hybrida'Stella deoro'.
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