This study was conducted to determine how nighttime supplemental lighting (NSL) duration and light intensity influence the growth and photosynthesis of young Cymbidium plants. Seven-month-old Cymbidium ‘Yang Guifei’ and ‘Wine Shower’ plants were grown under five NSL durations (2, 4, 6, 8, and 16 h) and three NSL light intensities (10, 100, and 200 µmol·m⁻²·s⁻¹) for 4 months, which provided 16 NSL light integrals ranging from 0 to 11.52 mol·m⁻²·d⁻¹ including 0 h NSL treatment. The NSL treatments were provided by 100% red LEDs, and CO₂ was supplied during the nighttime (16 h) at 800 µmol·mol⁻¹. Pseudobulb diameter, the number of leaves, and biomass accumulation significantly increased with increasing NSL duration and light intensity in both cultivars. These growth characteristics showed increasing trends with increasing NSL light integrals. In particular, pseudobulb diameter increased by 33 and 43% in ‘Yang Guifei’ and ‘Wine Shower,’ respectively, as the NSL light integral increased from 0 to 11.52 mol·m⁻²·d⁻¹. Relative chlorophyll contents decreased with increasing NSL light intensity in ‘Yang Guifei’. Photosynthetic assimilation rate (A_n) during NSL was promoted in response to increases of NSL duration and light intensity in both cultivars, implying that the A_n increased with increasing NSL light integrals. However, in this study, continuous lighting (16 h NSL) limited daytime photosynthesis. Daily A_n showed a positive correlation with pseudobulb diameter. These results indicated that NSL could accelerate the growth of young Cymbidium plants by inducing nighttime photosynthesis. In this study, considering that continuous NSL could inhibit the daytime photosynthesis, the 8 h NSL with 200 µmol·m⁻²·s⁻¹ treatment was the most effective for promoting the growth. This finding can be used to maximize the growth rate and shorten the cultivation time in Cymbidium production.

进行这项研究是为了确定夜间补充照明（NSL）的持续时间和光强度如何影响小ym兰植物的生长和光合作用。七个月大的大花'兰“杨贵妃”和“葡萄酒淋浴”植物在五个NSL持续时间（2、4、6、8和16 h）和三个NSL光照强度（10、100和200 µmol·）下生长m ^-2 ·s ^-1）4个月，其中包括0 h NSL处理，提供了16个NSL光积分，范围从0到11.52 mol·m ^-2 ·d ^-1。NSL处理由100％红色LED提供，并且在夜间（16小时）以800 µmol·mol ^-1的速度供应CO ₂。随着两个品种NSL持续时间和光照强度的增加，假鳞茎直径，叶片数量和生物量积累显着增加。这些生长特征显示出随着NSL光积分的增加而增加的趋势。特别地，当NSL光积分从0增加到11.52 mol·m ^-2 ·d ^-1时，“杨贵妃”和“葡萄酒淋浴”中的假灯泡直径分别增加了33％和43％。随着“杨贵妃” NSL光照强度的增加，叶绿素相对含量降低。NSL持续时间和光照强度的增加促进了NSL期间的光合同化率（A _n）升高，表明A _n随着NSL光积分的增加而增加。然而，在这项研究中，连续光照（16小时NSL）限制了白天的光合作用。每日A _n与假鳞茎直径呈正相关。这些结果表明，NSL可以通过诱导夜间光合作用来促进大花C兰植物的生长。在这项研究中，考虑到连续NSL可以抑制白天的光合作用，所以200μmol·m ^-2 ·s ^-1处理的8 h NSL最有效地促进了生长。该发现可用于最大化生长速度并缩短大花ym兰生产中的培养时间。