In-door germination and seedling growth of green and red lettuce under LED-light spectrum and subsequent effect on baby leaf lettuce

Submitted: 30 September 2021
Accepted: 26 May 2022
Published: 4 July 2022
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Authors

  • Cristian Hernández-Adasme Centre for Post-harvest Studies, Faculty of Agronomic Sciences, University of Chile, La Pintana, Santiago, Chile.
  • Herman Silva Functional Genomics and Bioinformatics Laboratory, Faculty of Agronomic Sciences, University of Chile, La Pintana, Santiago, Chile.
  • Víctor Escalona vescalona@uchile.cl Centre for Post-harvest Studies, Faculty of Agronomic Sciences, University of Chile, La Pintana, Santiago, Chile.

The spectrum and intensity of light play a significant role in the primary and secondary metabolism of plants. Low intensity can make the photosynthetic process less efficient, while inadequate spectrum can impair plant growth and quality. This study investigates the effect of different LED light spectra at low intensity on germination and growth of lettuce (Lactuca sativa L.) seedlings under a temperature-controlled chamber and the subsequent impact on mature plants grown in a greenhouse under natural light. The purpose was to reach a commercial plant seedling using a low amount of energy to achieve the yield potential in a shorter period. The experiment was carried out in three trials. In trial 1, the effect of different LED light wavelengths [100% blue (B); 100% red (R); mixed light 1 (52% blue, 27% green and 21% red) (BGR1), and mixed light 2 (29% blue, 53% green and 17% red and 1% far red) (BGR2)] at low intensity (55 μmol m–2 s–1 and 12 h light photoperiod) and darkness (control) on germination of two lettuce cultivars [‘Levistro’ (green) and ‘Carmolí’ (red)] was evaluated in a controlled temperature chamber (20±1.2°C). In trial 2, the effect of the same light conditions of the first experiment on agronomic characteristics and pigment contents of lettuce seedlings compared to the natural light (control: 451±66 μmol m–2 s–1) were evaluated. In trial 3, the seedlings developed under different LED light wavelengths were transplanted to evaluate the subsequent effect on the growth of baby lettuce cultivated hydroponically in the greenhouse under natural light. The results of this study show that red wavelength reduced germination percentage, while lights with a higher blue component (B and BGR1) accelerated germination and increased the number of germinated seeds in ‘Levistro’. Red also delayed germination and decreased the number of germinated seeds in ‘Carmolí’ compared to darkness. Seedlings of ‘Levistro’ had a higher fresh weight (FW) than ‘Carmolí’. In addition, FW increased under BGR2 and R, which coincided with the highest number of leaves and leaf length. Nevertheless, fresh weight was higher under BGR2 and B after transplanting, coinciding with the highest number of leaves. A higher blue component of the light (B and BGR1) increased the dry matter percentage (DMP) of seedlings, but there was no significant difference after transplanting. Chlorophyll (CHL) a and b content increased under BGR2; however, the highest CHL a/b ratio was observed under BGR1 in ‘Levistro’ and B in ‘Carmolí’, but it was higher after transplanting when seedlings were grown under B. The anthocyanin (ANT) content of ‘Carmolí’ seedlings was promoted by a higher blue component of the light (B and BGR1) but significantly increased under natural light (control) at the highest intensity. This work shows that varying the spectrum at low intensity can positively modify the growth and biochemical characteristics of lettuce seedlings, although the effect depends on the cultivar. This modification improves the performance of plants during greenhouse growth after transplanting, especially seedlings grown under B and BGR2.

Highlights
- Blue light enhanced germination and increased the number of germinated seeds of green lettuce.
- High blue component lights improved the morphology, dry matter percentage, and chlorophyll a/b ratio of lettuce seedlings.
- Blue and full-spectrum lights applied to lettuce seedlings affect fresh weight after transplanting.
- The anthocyanin content of seedlings was stimulated by blue light at 55 μmol m–2 s–1, but even more so by PAR of natural light at 451 μmol m–2 s–1.

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Amoozgar A, Mohammadi A, Sabzalian M, 2017. Impact of light-emitting diode irradiation on photosynthesis, phytochemical composition and mineral element content of lettuce cv. Grizzly. Photosynthetica 55:85-95. DOI: https://doi.org/10.1007/s11099-016-0216-8
Baek G, Kim M, Kim C, Choi C, Jin B, Son J, Kim H, 2013. The effect of LED light combination on the anthocyanin expression of lettuce. IFAC Proceedings Volumes 46:120-3. DOI: https://doi.org/10.3182/20130327-3-JP-3017.00029
Balliu A, Maršiü N, Gruda N, 2017. Seedling production. In: W. Baudoin, A. Nersisyan, A. Shamilov, A. Hodder, D. Gutiérrez, S. de Pascale, S. Nicola, N. Gruda, L. Urban, J. Tanny (Eds.), Good agricultural practices for greenhouse vegetable production in the South East European countries - Principles for sustainable intensification of smallholder. FAO Plant Production and Protection Paper, Rome, Italy, Volume 230, pp. 189-206. DOI: https://doi.org/10.18690/978-961-286-045-5.34
Bartucca M, Guiducci M, Falcinelli B, Del Buono D, Benincasa P, 2020. Blue:Red LED light proportion affects vegetative parameters, pigment content, and oxidative status of einkorn (Triticum monococcum L. ssp. monococcum) wheatgrass. J. Agric. Food Chem. 68:8757-63. DOI: https://doi.org/10.1021/acs.jafc.0c03851
Battistoni B, Amorós M, Tapia M, Escalona V, 2021. Effect of blue, green or red LED light on the functional quality of spinach (Spinacia oleracea L.). Rev. FCA UNCuyo. 53:98-108. DOI: https://doi.org/10.48162/rev.39.010
Benincasa P, Tosti G, Farneselli M, Maranghi S, Bravi E, Marconi O, Falcinelli B, Guiducci M, 2020. Phenolic content and antioxidant activity of einkorn and emmer sprouts and wheatgrass obtained under different radiation wavelengths. Ann. Agric. Sci. 65:68-76. DOI: https://doi.org/10.1016/j.aoas.2020.02.001
Bian Z, Cheng R, Yang Q, Wang J, 2016. Continuous light from red, blue, and green light-emitting diodes reduces nitrate content and enhances phytochemical concentrations and antioxidant capacity in lettuce. J. Am. Soc. Hortic. Sci. 141:186-95. DOI: https://doi.org/10.21273/JASHS.141.2.186
Bohne F, Linden H, 2002. Regulation of carotenoid biosynthesis genes in response to light in Chlamydomonas reinhardtii. Biochim Biophys Acta 1579:26-34. DOI: https://doi.org/10.1016/S0167-4781(02)00500-6
Borowski E, Michałek S, Rubinowska K, Hawrylak-Nowak B, Grudziński W, 2015. The effects of light quality on photosynthetic parameters and yield of lettuce plants. Acta Sci. Pol. Hortorum Cultus 14:177-88.
Brazaitytė A, Sakalauskienė S, Samuolienė G, Jankauskienė J, Viršilė A, Novičkovas A, Sirtautas R, Miliauskienė J, Vaštakaitė V, Dabašinskas L, Duchovskis P, 2015. The effects of LED illumination spectra and intensity on carotenoid content in Brassicaceae microgreens. Food Chem. 173:600-6. DOI: https://doi.org/10.1016/j.foodchem.2014.10.077
Cammarisano L, Donnison I, Robson P, 2021. The effect of red & blue rich LEDs vs fluorescent light on Lollo rosso lettuce morphology and physiology. Front. Plant Sci. 12:603411. DOI: https://doi.org/10.3389/fpls.2021.603411
Cantliffe D, Sung Y, Nascimento W, 2000. Lettuce seed germination. Hortic Rev. 24:229-275. DOI: https://doi.org/10.1002/9780470650776.ch5
Carvalho S, Folta K, 2016. Green light control of anthocyanin production in microgreens. Acta Hortic. 1134:13-8. DOI: https://doi.org/10.17660/ActaHortic.2016.1134.2
Casal J, Candia A, Sellaro R, 2014. Light perception and signalling by phytochrome A. J. Exp. Bot. 65:2835-45. DOI: https://doi.org/10.1093/jxb/ert379
Chang C, Chang K, 2014. The growth response of leaf lettuce at different stages to multiple wavelength-band light-emitting diode lighting. Sci. Hortic. 179:78-84. DOI: https://doi.org/10.1016/j.scienta.2014.09.013
Chen X, Guo W, Xue X, Wang L, Qiao X, 2014. Growth and quality responses of ‘Green Oak Leaf’ lettuce as affected by monochromic or mixed radiation provided by fluorescent lamp (FL) and light-emitting diode (LED). Sci. Hortic. 172:168-75. DOI: https://doi.org/10.1016/j.scienta.2014.04.009
Cho J, Ryu J, Jeong Y, Park J, Song J, Amasino R, Noh B, Noh Y, 2012. Control of seed germination by light-induced histone arginine demethylation activity. Dev. Cell 22:736-48. DOI: https://doi.org/10.1016/j.devcel.2012.01.024
Choong T, He J, Qin L, Lee S, 2018. Quality of supplementary LED lighting effects on growth and photosynthesis of two different Lactuca recombinant inbred lines (RILs) grown in a tropical greenhouse. Photosynthetica 56:1278-86. DOI: https://doi.org/10.1007/s11099-018-0828-2
Chung I, Paudel N, Kim S, Yu C, Ghimire B, 2020. The influence of light wavelength on growth and antioxidant capacity in Pachyrhizus erosus (L.) Urban. J. Plant Growth Regul. 39:296-312. DOI: https://doi.org/10.1007/s00344-019-09982-1
Clavijo-Herrera J, van Santen E, Gómez C, 2018. Growth, water-use efficiency, stomatal conductance, and nitrogen uptake of two lettuce cultivars grown under different percentages of blue and red light. Horticulturae 4:16. DOI: https://doi.org/10.3390/horticulturae4030016
Contreras S, Bennet M, Metzger J, Tay D, Nerson H, 2009. Red to far-red ratio during seed development affects lettuce seed germinability and longevity. HortSci. 44:130-4. DOI: https://doi.org/10.21273/HORTSCI.44.1.130
Cui J, Song S, Yu J, Liu H, 2021. Effect of daily light integral on cucumber plug seedlings in artificial light plant factory. Horticulturae 7:139. DOI: https://doi.org/10.3390/horticulturae7060139
Currey C, Hutchinson V, López R, 2012. Growth, morphology, and quality of rooted cuttings of several herbaceous annual bedding plants are influenced by photosynthetic daily light integral during root development. HortSci. 47:25-30. DOI: https://doi.org/10.21273/HORTSCI.47.1.25
Dusadeerungsikul P, Liakos V, Morari F, Nof S, Bechar A. 2020. Smart action. In: A. Castrignano, G. Buttafuoco, R. Khosla, A. Mouazen, D. Moshou, O. Naud (Eds.), Agricultural internet of things and decision support for precision smart farming, Academic Press Ltd., Massachusetts, United States, pp. 225-77. DOI: https://doi.org/10.1016/B978-0-12-818373-1.00005-6
Evenari M, Neumann G, Stein G, 1957. Action of blue light on the germination of seeds. Nature 180:609-10. DOI: https://doi.org/10.1038/180609b0
Fan X, Zang J, Xu Z, Guo S, Jiao X, Liu X, Gao Y, 2013. Effects of different light quality on growth, chlorophyll concentration and chlorophyll biosynthesis precursors of non-heading Chinese cabbage (Brassica campestris L.). Acta Physiol. Plant. 35:2721-6. DOI: https://doi.org/10.1007/s11738-013-1304-z
Frank S, 1946. The effectiveness of the spectrum in chlorophyll formation. J. Gen. Physiol. 29:157-79. DOI: https://doi.org/10.1085/jgp.29.3.157
Frede K, Schreiner M, Zrenner R, Graefe J, Baldermann S, 2018. Carotenoid biosynthesis of pak choi (Brassica rapa ssp. chinensis) sprouts grown under different light emitting diodes during the diurnal course. Photochem. Photobiol. Sci. 17:1289-300. DOI: https://doi.org/10.1039/C8PP00136G
Fu W, Li P, Wu Y, 2012. Effects of different light intensities on chlorophyll fluorescence characteristics and yield in lettuce. Sci. Hortic. 135:45-51. DOI: https://doi.org/10.1016/j.scienta.2011.12.004
Giusti M, Wrolstad R, 2001. Characterization and measurement of anthocyanins by UV-visible spectroscopy. Curr. Protoc. Food Anal. Chem. F1.2.1-F1.2.13. DOI: https://doi.org/10.1002/0471142913.faf0102s00
González-Zertuche L, Orozco-Segovia A, 1996. Data analysis methods in seed germination, an example: Manfreda Brachystachya. Bol. Soc. Bot. México 58:15-30.
Gregorio N, Herbohn J, Harrison S, 2010. Guide to quality seedling production in smallholder nurseries. Visayas State University: Leyte, Philippines, pp. 1-43.
Hernández R, Kubota C, 2014. Growth and morphological response of cucumber seedlings to supplemental red and blue photon flux ratios under varied solar daily light integrals. Sci. Hortic. 173:92-9. DOI: https://doi.org/10.1016/j.scienta.2014.04.035
Hernández R, Kubota C, 2016. Physiological responses of cucumber seedlings under different blue and red photon flux ratios using LEDs. Environ. Exp. Bot. 121:6-74. DOI: https://doi.org/10.1016/j.envexpbot.2015.04.001
Hoenecke M, Bula R, Tibbitts T, 1992. Importance of ‘blue’ photon levels for lettuce seedlings grown under red-light-emitting diodes. HortSci. 27:427-30. DOI: https://doi.org/10.21273/HORTSCI.27.5.427
Hogewoning S, Trouwborst G, Maljaars H, Poorter H, van Ieperen W, Harbinson J, 2010. Blue light dose-responses of leaf photosynthesis, morphology, and chemical composition of Cucumis sativus grown under different combinations of red and blue light. J. Exp. Bot. 61:3107-17. DOI: https://doi.org/10.1093/jxb/erq132
Hosotani S, Yamauchi S, Kobayashi H, Fuji S, Koya S, Shimazaki K, Takemiya A, 2021. A BLUS1 kinase signal and a decrease in intercellular CO2 concentration are necessary for stomatal opening in response to blue light. Plant Cell. 33:1813-27. DOI: https://doi.org/10.1093/plcell/koab067
Ilić Z, Fallik E, 2017. Light quality manipulation improves vegetable quality at harvest and postharvest: a review. Environ. Exp. Bot. 139:79-90. DOI: https://doi.org/10.1016/j.envexpbot.2017.04.006
International seed testing association (ISTA), 1999. International rules for seed testing. Seed Sci. Technol. 23:1-269.
Johkan M, Shoji K, Goto F, Hashida S, Yoshihara T, 2010. Blue light-emitting diode light irradiation of seedlings improves seedling quality and growth after transplanting in red leaf lettuce. HortSci. 45:1809-14. DOI: https://doi.org/10.21273/HORTSCI.45.12.1809
Johkan M, Shoji K, Goto F, Hashida S, Yoshihara T, 2012. Effect of green light wavelength and intensity on photomorphogenesis and photosynthesis in Lactuca sativa. Environ. Exp. Bot. 75:128-33. DOI: https://doi.org/10.1016/j.envexpbot.2011.08.010
Kang J, KrishnaKumar S, Sua S, Jeong B, Hwang S, 2013. Light intensity and photoperiod influence the growth and development of hydroponically grown leaf lettuce in a closed-type plant factory system. Hortic. Environ. Biotechnol. 54:501-9. DOI: https://doi.org/10.1007/s13580-013-0109-8
Kelly N, Choe D, Meng Q, Runkle E, 2020. Promotion of lettuce growth under an increasing daily light integral depends on the combination of the photosynthetic photon flux density and photoperiod. Sci. Hortic. 272:109565. DOI: https://doi.org/10.1016/j.scienta.2020.109565
Kim M, Moon Y, Tou J, Mou B, Waterlan N, 2016. Nutritional value, bioactive compounds and health benefits of lettuce (Lactuca sativa L.). J. Food Compos. Anal. 49:19-34. DOI: https://doi.org/10.1016/j.jfca.2016.03.004
Kozai T, 2020. PFAL business and R&D in Asia and North America: status and perspectives. In: T. Kozai, G. Niu, M. Takagaki (Eds.), Plant factory: an indoor vertical farming system for efficient quality food production (2nd ed.). Academic Press Ltd., Massachusetts, United States, pp. 35-76. DOI: https://doi.org/10.1016/B978-0-12-816691-8.00003-0
Kozai T, Niu G, 2020a. Plant factory as a resource-efficient closed plant production system. In: T. Kozai, G. Niu, M. Takagaki (Eds.), Plant factory: an indoor vertical farming system for efficient quality food production (2nd ed.). Academic Press Ltd., Massachusetts, United States, pp. 35-76. DOI: https://doi.org/10.1016/B978-0-12-816691-8.00005-4
Kozai T, Niu G, 2020b. Role of the plant factory with artificial lighting (PFAL) in urban areas. In: T. Kozai, G. Niu, M. Takagaki (Eds.), Plant factory: an indoor vertical farming system for efficient quality food production (2nd ed.). Academic Press Ltd., Massachusetts, United States, pp. 35-76. DOI: https://doi.org/10.1016/B978-0-12-816691-8.00002-9
Kwack Y, Kim Y, Hwang H, Chun C, 2015. Growth and quality of sprouts of six vegetables cultivated under different light intensity and quality. Hortic. Environ. Biotechnol. 56:437-43. DOI: https://doi.org/10.1007/s13580-015-1044-7
Lara O, Amorós A, Tapia M, Escalona V, 2021. Effect of a photoselective filter on the yield and postharvest quality of ‘Viroflay’ baby spinach (Spinacia oleracea L.) leaves cultivated in a hydroponic system. Sci. Hortic. 277:109804. DOI: https://doi.org/10.1016/j.scienta.2020.109804
Lee M, Son K, Oh M, 2016. Increase in biomass and bioactive compounds in lettuce under various ratios of red to far-red LED light supplemented with blue LED light. Hortic. Environ. Biotechnol. 57:139-47. DOI: https://doi.org/10.1007/s13580-016-0133-6
Lee J, Kang W, Park K, Son J, 2017. Spectral dependence of electrical energy-based photosynthetic efficiency at single leaf and canopy levels in green- and red-leaf lettuces. Hortic. Environ. Biotechnol. 58:111-8. DOI: https://doi.org/10.1007/s13580-017-0154-9
Li Y, He N, Hou J, Xu L, Liu C, Zhang J, Wang Q, Zhang X, Wu X, 2018. Factors influencing leaf chlorophyll content in natural forests at the biome scale. Front. Ecol. Evol. 6:64. DOI: https://doi.org/10.3389/fevo.2018.00064
Lichtenthaler H, Wellburn A, 1983. Determinations of total carotenoids and chlorophylls a and b of leaf extracts in different solvents. Biochem. Soc. Trans. 11:591-2. DOI: https://doi.org/10.1042/bst0110591
Lin K, Huang M, Huang W, Hsu M, Yang Z, Yang C, 2013. The effects of red, blue, and white light-emitting diodes on the growth, development, and edible quality of hydroponically grown lettuce (Lactuca sativa L. var. capitata). Sci. Hortic. 150:86-91. DOI: https://doi.org/10.1016/j.scienta.2012.10.002
López R, Fisher P, Runkle E, 2017. Introduction to specialty crop lighting. In: R. López, E. S. Runkle (Eds.), Light management in controlled environments. Meister Media Worldwide, Willoughby, OH, pp. 12-20.
Meng X, Xing T, Wang X. 2004. The role of light in the regulation of anthocyanin accumulation in Gerbera hybrid. Plant Growth Regul. 44:243-50. DOI: https://doi.org/10.1007/s10725-004-4454-6
Nabli R, Achour S, Jourdes M, Teissedre P, Hela A, Ezzili B, 2013. Anthocyanins composition and extraction from grenache noir (Vitis vinifera L.) vine leaf using an experimental design II- by ethanol or sulfur dioxide in acidified water. J. Int. Des Sci. Vigne Vin 47:301-10. DOI: https://doi.org/10.20870/oeno-one.2013.47.4.1561
Nájera C, Urrestarazu M, 2019. Effect of the intensity and spectral quality of LED light on yield and nitrate accumulation in vegetables. HortSci. 54:1745-50. DOI: https://doi.org/10.21273/HORTSCI14263-19
Naznin M, Lefsrud M, Gravel V, Azad M, 2019. Blue light added with red LEDs enhance growth characteristics, pigments content, and antioxidant capacity in lettuce, spinach, kale, basil, and sweet pepper in a controlled environment. Plants 8:93. DOI: https://doi.org/10.3390/plants8040093
Neff M, 2012. Light-mediated seed germination: connecting phytochrome B to gibberellic acid. Dev. Cell 22:687-8. DOI: https://doi.org/10.1016/j.devcel.2012.04.003
Ngilah E, Tsan F, Yap B, 2018. Photoperiod and light spectrum effects on growth, pigment and ascorbic acid content of Lactuca sativa cv. Fire Red under controlled growth environment. Int. Food Res. J. 25:1300-8.
Okamoto K, Yanagi T, Kondo S, 1997. Growth and morphogenesis of lettuce seedlings raised under different combinations of red and blue light. Acta Hortic. 435:149-58. DOI: https://doi.org/10.17660/ActaHortic.1997.435.14
Paniagua G, Velázquez S, Cruz A, Hernández C, Domínguez F, Rico F, 2016. Pulsed LED light in germination and growth of lettuce seeds. Bothalia J. 46:13.
Patel E, Chandawat D, Patel Y, 2017. Effect of light on seed germination of Vigna radiata. EJPMR 4:444-8.
Pérez-López U, Miranda-Apodaca J, Muñoz-Rueda A, Mena-Petite A, 2013. Lettuce production and antioxidant capacity are differentially modified by salt stress and light intensity under ambient and elevated CO2. Plant Physiol. 170:1517-25. DOI: https://doi.org/10.1016/j.jplph.2013.06.004
Petrella D, Metzger J, Blakeslee J, Nangle E, Gardner D, 2016. Anthocyanin production using rough bluegrass treated with high-intensity light. HortSci. 51:111120. DOI: https://doi.org/10.21273/HORTSCI10878-16
Pizarro L, Stange C, 2009. Light-dependent regulation of carotenoid biosynthesis in plants. Cienc. Investig. Agrar. 36:143-62. DOI: https://doi.org/10.4067/S0718-16202009000200001
Poppe C, Sweere, U, Drumm‐Herrel H, Schäfer E, 1998. The blue light receptor cryptochrome 1 can act independently of phytochrome A and B in Arabidopsis thaliana. Plant J. 16:465-71. DOI: https://doi.org/10.1046/j.1365-313x.1998.00322.x
Proshkin Y, Semenova N, Smirnov A, Chilingaryan N, 2020. The LED phyto lighting for improving the environmental friendliness of growing and productivity of lettuce varieties with red and green leaves. IOP Conf. Ser. Earth Environ. Sci. 578. DOI: https://doi.org/10.1088/1755-1315/578/1/012013
Rodríguez I, Adam G, Durán J, 2008. Ensayos de germinación y análisis de viabilidad y vigor en semillas. Agric. Rev. Agropecuaria 912:836-42.
Sawada Y, Aoki M, Nakaminami K, Mitsuhashi W, Tatematsu K, Kushiro T, Koshiba T, Kamiya Y, Inoue Y, Nambara E, Toyomasu T, 2008. Phytochrome- and gibberellin-mediated regulation of abscisic acid metabolism during germination of photoblastic lettuce seeds. Plant Physiol. 146:1386-96. DOI: https://doi.org/10.1104/pp.107.115162
Shinomura T, Nagatani A, Hanzawa H, Kubota M, Watanabe M, Furuya M, 1996. Action spectra for phytochrome A- and B-specific photoinduction of seed germination in Arabidopsis thaliana. Proc. Natl. Acad. Sci. U. S. A. 93:8129-33. DOI: https://doi.org/10.1073/pnas.93.15.8129
Simkin A, Zhu C, Kuntz M, Sandmann G, 2003. Light-dark regulation of carotenoid biosynthesis in pepper (Capsicum annuum) leaves. J. Plant Physiol. 160:439-43. DOI: https://doi.org/10.1078/0176-1617-00871
Small J, Spruit C, Blaauw-Jansen G, Blaauw O, 1979. Action spectra for light-induced germination in dormant lettuce seeds. Planta 144:133-6. DOI: https://doi.org/10.1007/BF00387261
Son K, Lee J, Oh Y, Kim D, Oh M, 2017. Growth and bioactive compound synthesis in cultivated lettuce subject to light-quality changes. HortSci. 52:584-91. DOI: https://doi.org/10.21273/HORTSCI11592-16
Son K, Oh M, 2013. Leaf shape, growth, and antioxidant phenolic compounds of two lettuce cultivars grown under various combinations of blue and red Light-emitting Diodes. HortSci. 48:988-95. DOI: https://doi.org/10.21273/HORTSCI.48.8.988
Song J, Cao K, Hao Y, Song S, Su W, Liu H, 2019. Hypocotyl elongation is regulated by supplemental blue and red light in cucumber seedling. Gene 707:117-25. DOI: https://doi.org/10.1016/j.gene.2019.04.070
Sood S, Gupta V, Tripathy B, 2005. Photoregulation of the greening process of wheat seedlings grown in red light. Plant Mol. Biol. 59:269-87. DOI: https://doi.org/10.1007/s11103-005-8880-2
Stutte G, Edney S, Skerrit T, 2009. Photoregulation of bioprotectant content of red leaf lettuce with light-emitting diodes. HortSci. 44:79-82. DOI: https://doi.org/10.21273/HORTSCI.44.1.79
Tosti G, Benincasa P, Cortona R, Falcinelli B, Farneselli M, Guiducci M, Onofri A, Pannacci E, Tei F, Giulietti, M, 2017. Growing lettuce under multispectral light-emitting diodes lamps with adjustable light intensity. Ital. J. Agron. 13:883. DOI: https://doi.org/10.4081/ija.2017.883
Trojak M, Skowron E, 2017. Role of anthocyanins in high-light stress response. World Sci. News 81(2):150-68.
Wang J, Lu W, Tong Y, Yang Q, 2016. Leaf morphology, photosynthetic performance, chlorophyll fluorescence, stomatal development of lettuce (Lactuca sativa L.) exposed to different ratios of red light to blue light. Front. Plant Sci. 7:250. DOI: https://doi.org/10.3389/fpls.2016.00250
Yamaguchi S, Kamiya Y, 2002. Gibberellins and light-stimulated seed germination. J. Plant Growth Regul. 20:369-76. DOI: https://doi.org/10.1007/s003440010035
Yousef A, Ali M, Rizwan H, Ahmed M, Ali W, Kalaji H, Elsheery N, Wróbel J, Xu J, Chen F, 2021. Effects of light spectrum on morpho-physiological traits of grafted tomato seedlings. PLoS One 16:e0250210. DOI: https://doi.org/10.1371/journal.pone.0250210
Zhang D, Yuan S, Xu F, Zhu F, Yuan M, Ye H, Guo H, Lv X, Yin Y, Lin H, 2016. Light intensity affects chlorophyll synthesis during greening process by metabolite signal from mitochondrial alternative oxidase in Arabidopsis. Plant Cell Environ. 39:12-25. DOI: https://doi.org/10.1111/pce.12438
Zhang T, Folta K, 2012. Green light signaling and adaptive response. Plant Signal. Behav. 7:1-4. DOI: https://doi.org/10.4161/psb.7.1.18635

How to Cite

Hernández-Adasme, C., Silva, H., & Escalona, V. (2022). In-door germination and seedling growth of green and red lettuce under LED-light spectrum and subsequent effect on baby leaf lettuce. Italian Journal of Agronomy, 17(2). https://doi.org/10.4081/ija.2022.1982