Institute of Forest Protection, Zhejiang Academy of Forestry, Hangzhou, China.
Forest Food Research Institute, Zhejiang Academy of Forestry, Hangzhou, China.
PLoS One. 2022 Apr 28;17(4):e0267632. doi: 10.1371/journal.pone.0267632. eCollection 2022.
Target seedling cultivation pursues high quality and nutrient utilization instead of increasing growth and size. Exposure to light-emitting diode (LED) spectra is a well-known approach that can accelerate growing speed in tree seedlings, but it is still unknown whether seedling quality and nutrient utilization would be further improved with exogeneous polymer additives. Luohan pine (Podocarpus macrophyllus) seedlings were exposed to red (red-green-blue lights, 71.7%-13.7%-14.6%), green (26.2%-56.4%-17.4%), and blue (17.8%-33.7%-48.5%) LED-light spectra with half receiving leaf spray by chitosan oligosaccharides (Cos) at a rate of 2 ppm (w/w) and the other half receiving only water. The red-light spectrum promoted height, biomass, nutrient utilization, and quality assessment (DQI) in water-sprayed seedlings. The Cos spray enhanced fine-root growth, protein, and chlorophyll-b contents with elevated nutrient utilization and quality in seedlings in the green-light spectrum. DQI was found to have a positive relationship with phosphorus utilization. In conclusion, although the red-light LED spectrum can promote seedling growth, green light combined with Cos spray is recommended with the aim of maintaining seedling quality and increasing P utilization in Luohan pine seedlings.
目标幼苗培育追求高质量和养分利用率，而不是增加生长和大小。暴露在发光二极管（LED）光谱下是一种众所周知的方法，可以加速树木幼苗的生长速度，但目前尚不清楚外源聚合物添加剂是否会进一步提高幼苗的质量和养分利用率。罗汉松（Podocarpus macrophyllus）幼苗暴露在红光（红绿蓝光，71.7%-13.7%-14.6%）、绿光（26.2%-56.4%-17.4%）和蓝光（17.8%-33.7%-48.5%）LED 光谱下，一半的叶片接受壳寡糖（Cos）以 2 ppm（w/w）的浓度喷雾，另一半只接受水。红光光谱促进了喷水幼苗的高度、生物量、养分利用率和质量评估（DQI）。Cos 喷雾增强了细根生长、蛋白质和叶绿素 b 含量，提高了绿光光谱下幼苗的养分利用率和质量。发现 DQI 与磷利用率呈正相关。总之，虽然红光 LED 光谱可以促进幼苗生长，但建议结合 Cos 喷雾使用绿光，以维持罗汉松幼苗的质量并增加 P 利用率。
