Vegetable Systems Modelling Section, Institute of Horticultural Production Systems, University of Hannover, Hannover, Germany.
PLoS One. 2023 Sep 14;18(9):e0291601. doi: 10.1371/journal.pone.0291601. eCollection 2023.
There is an increasing interest in alternatives to peat in growing media due to environmental constraints. However, plants grown in peat substitutes often show impaired growth compared to plants grown in peat-based media. Hence, it would be interesting to know whether these deficiencies can be compensated by supplementing other growth factors, e.g. light. The present study aims to investigate the interactive nature between growing media and supplemental lighting on plant growth and morphology, and to examine whether supplemental light emitting diode (LED) lighting may compensate adverse growing media effects. Basil (Ocimum basilicum L.) and Chinese cabbage (Brassica rapa subsp. pekinensis) were grown in different growing media consisting of peat, green compost, coconut pulp, wood fibre, perlite and sphagnum moss under blue, red and far-red supplemental LED lighting. We found significant interactions between growing media and supplemental photosynthetically active radiation (PAR) on plant growth, morphology and development. At low light intensities, peat-based and substituted growing media performed similarly, whereas with increasing light intensities the peat-based growing media significantly outperformed their alternatives. The substrate choice determines the required amount of supplemental light to compensate for adverse growing media effects and the amount varies depending on plant species and season. Thereby, it was indicated that red light alleviates adverse growing media effects best. We also found that far-red light is not effective when background PAR is low and becomes more effective under high background PAR. The implications and prospects of the results are discussed.
由于环境限制，人们对泥炭替代物在生长介质中的应用越来越感兴趣。然而，与在基于泥炭的介质中生长的植物相比，在泥炭替代品中生长的植物的生长往往受到损害。因此，了解这些缺陷是否可以通过补充其他生长因子（例如光）来弥补将是很有趣的。本研究旨在探讨生长介质和补充光照对植物生长和形态的相互作用，并研究补充发光二极管（LED）光照是否可以弥补不利的生长介质的影响。罗勒（Ocimum basilicum L.）和白菜（Brassica rapa subsp. pekinensis）分别在不同的生长介质中生长，这些生长介质由泥炭、绿肥、椰子果肉、木纤维、珍珠岩和泥炭藓组成，同时接受蓝、红和远红三种补充 LED 光照。我们发现生长介质和补充光合有效辐射（PAR）对植物生长、形态和发育的显著相互作用。在低光强下，基于泥炭和替代生长介质的性能相似，而随着光强的增加，基于泥炭的生长介质的性能明显优于替代生长介质。基质的选择决定了补偿不利生长介质影响所需的补充光量，而所需的光量因植物种类和季节而异。因此，红光是缓解不利生长介质影响的最佳选择。我们还发现，当背景 PAR 较低时，远红光是无效的，而在高背景 PAR 下，远红光则变得更加有效。讨论了结果的意义和前景。
