Wiebel J, Chacko E K, Downton W J, Lüdders P
CSIRO, Division of Horticulture, PMB 44, Winnellie, N.T. 0821, Australia.
Tree Physiol. 1994 Mar;14(3):263-74. doi: 10.1093/treephys/14.3.263.
The influence of shading intensity on growth, morphology and leaf gas exchange of mangosteen (Garcinia mangostana L.) seedlings was investigated over a 2-year period. Diurnal gas exchange studies revealed significantly higher carbon gain for leaves grown in 20 or 50% shade compared to leaves grown in 80% shade. Seedlings grown in 20 or 50% shade accumulated significantly more dry weight than seedlings grown in 80% shade during the 2-year study period. Seedlings grown in decreased shade showed decreased leaf size, increased leaf thickness, lower specific leaf area (SLA) and higher stomatal frequency. Less shaded seedlings also allocated relatively more dry matter to roots than shaded seedlings and exhibited a significant reduction in leaf area relative to total plant dry weight (leaf area ratio). Increased leaf number, enhanced branching and shorter internodes resulted in a more compact appearance of less shaded seedlings. Irrespective of light conditions, mangosteen seedlings exhibited inherently slow growth because of low photosynthetic rates per unit leaf area, low SLA, low leaf area ratios and inefficient root systems.
在两年时间里，研究了遮荫强度对山竹（Garcinia mangostana L.）幼苗生长、形态和叶片气体交换的影响。日间气体交换研究表明，与在80%遮荫条件下生长的叶片相比，在20%或50%遮荫条件下生长的叶片碳增益显著更高。在为期两年的研究期间，在20%或50%遮荫条件下生长的幼苗积累的干重显著高于在80%遮荫条件下生长的幼苗。在遮荫程度降低条件下生长的幼苗叶片尺寸减小、叶片厚度增加、比叶面积（SLA）降低且气孔频率更高。与遮荫幼苗相比，遮荫程度较低的幼苗向根部分配的干物质相对更多，并且相对于植株总干重的叶面积（叶面积比）显著降低。叶片数量增加、分枝增强和节间缩短导致遮荫程度较低的幼苗外观更紧凑。无论光照条件如何，由于单位叶面积光合速率低、SLA低、叶面积比低和根系效率低，山竹幼苗本身生长缓慢。
