Light initiates plant photosynthesis, and plant growth depends on light. In order to explore the effects of long-term dark treatment on photosynthesis and leaf growth of plants, this study compared and analyzed the growth state, pigment content, antioxidant capacity, photosynthetic capacity and chlorophyll fluorescence of the leaves of Syzygium rehderianum Merr. and L.M. Perry under full sunlight (natural full sunlight) and a dark treatment. The results showed that the photosynthesis and development of leaves were significantly inhibited after the dark treatment day 3. After the dark treatment day 6, the length and width of the leaves and the synthesis of photosynthetic pigments were significantly lower than those in leaves under full sunlight. Compared with those under full sunlight, the net photosynthetic rate (Pn), maximal quantum yield of PSII photochemistry (F_v/F_m), nonphotochemical quenching and actual photochemical efficiency (Yield) of young and mature leaves were significantly reduced after the dark treatment day 6. These results indicated that the timing of long-term dark treatment caused stress to the leaves. It directly affected the photosynthesis of leaves by affecting the absorption of light energy, inhibiting the synthesis of photosynthetic pigments and destroying the activity of the photosystem II (PSII) reaction center, which ultimately affected the growth and development of plant leaves.

光照引发植物的光合作用，而植物的生长则取决于光照。为了探索长期暗处理对植物光合作用和叶片生长的影响，本研究比较并分析了紫丁香叶片的生长状态，色素含量，抗氧化能力，光合能力和叶绿素荧光。梅尔 和LM Perry在充满阳光（自然的充满阳光）和黑暗的环境下。结果表明，黑暗处理第3天后，叶片的光合作用和发育受到明显抑制。黑暗处理第6天后，叶片的长度和宽度以及光合色素的合成明显低于全日照下的叶片。 。与日照相比，PSII光化学的净光合速率（P n），最大量子产率（F _v / F _m），在黑暗处理第6天后，幼嫩叶片和成熟叶片的非光化学猝灭和实际光化学效率（Yield）显着降低。这些结果表明，长期黑暗处理的时机会对叶片造成压力。它通过影响光能的吸收直接影响叶片的光合作用，抑制光合色素的合成，破坏光系统II（PSII）反应中心的活性，最终影响植物叶片的生长发育。