The Effects of Light Treatments on Growth and Flowering Characteristics of Oncidesa Gower Ramsey ‘Honey Angel’ at Different Growth Stages
, Meng-Yuan Huang 3, Chung-I Chen 4, Kuan-Hung Lin 5,* and Chih-Pei Shen 2,*Round 1
Reviewer 1 Report
1. It is not easy for readers to understand the 3 stages (G2-G4) in the abstract section.
2. It was suggested to simplify the results and exhibited the important results in the abstract section.
3. Maintain consistency in font (The inflorescence develops from the pseudobulb base or leaf axil………)
4. Misordered references, please check.
5. The introduction lacks an introduction to the impacts of different light qualities on Orchidaceae (or plants), or why do authors select Full spectrum, Deep red/white (DR/W) - Medium blue (MB), Deep red/white (DR/W) - Low blue (LB) for experiment?
6. It was suggested to add the light spectrum of the LEDs used in the experiment.
7. …….placed in a TDARES greenhouse under an 8 h photoperiod. How to control the photoperiod in a greenhouse, when is the experimental season? Please provide more details on the experiment details and the greenhouse used in the study.
8. why did the author set the mean photosynthetic daily light integral measured at each location ranged 300 to 400 μmol s -1?
9. Has the consistency of light intensity been maintained, and what is the light intensity? If not, it is the dual effect of light intensity and spectrum.
10. No significant differences were observed in the effects of type of light source (T), supplemental light duration (S) in PL, however, significant differences were observed in their interaction (T×S) effects in Table 2. Please check the result or explain the possible reasons. Similar results are also found in Table 3 and Table 5, please check and confirm.
11. The discussion seems insufficient and please explain possible reasons about the results.
12. Are the selected indicators sufficient to characterize the growth status of plants.
Author Response
- It is not easy for readers to understand the 3 stages (G2-G4) in the abstract section.
- It was suggested to simplify the results and exhibited the important results in the abstract section
Response: We have simplified the description of the lighting effects of 3 stages (G2-G4) to make it easier for readers to understand (Line 33- 38).
“MB-1 treatment promoted PT at both G3 and G4, whereas MB-2 treatment increased PW at both G2 and G4. Both MB-1 and LB-1 treatments had augmented effects on PL respectively at G2 and G3. The PW, FL, FB, and FN increased with additional light time and reached maxima under MB-2 treatment at G4 compared to other treatments and controls. Early flowering and an increased number of flowers at G4 were observed in plants grown under MB-2 treatment.”
- Maintain consistency in font (The inflorescence develops from the pseudobulb base or leaf axil………)
Response: Thank you very much for your suggestion. We have proofread the entire article and revised it to the same font accordingly.
- Misordered references, please check.
Response: Thanks again for your suggestion. We have double checked the reference orders and also added new references to both Introduction and Discussion as well.
Chatield, S.P.; Stirnberg, P.; Forde, B.G.; Leyser, O. The hormonal regulation of axillary bud growth in Arabidopsis. Plant J. 2000, 24, 159–169.
McArtney, S.; Obermiller, J.D. Effect of notching, 6-benzyladenine, and 6-benzyladenine plus gibberellin A4+A7 on budbreak and shoot development from paradormant buds on the leader of young apple trees. https://doi.org/10.21273/HORTTECH.25.2.233. Technol Prod Rep. 2015, 25, 233–237.
Zhang, D.; Zhao, X.W.; Li, Y.Y.; Ke, S.J.; Yin, W.L.; Lan, S.; Liu, Z.J. Advances and prospects of orchid research and industrialization. Horticulture Research, 2022, 9, uhac220.
Lazzarin, M.; Meisenburg, M.; Meijer, D.; van Ieperen, W.; Marcelis, L.F.M.; Kappers, I.F.; van der Krol, A.R.; van Loon, J.J.A.; Dicke, M. LEDs make it resilient: effects on plant growth and defense. Trends in Plant Science, 2021, 26, 496–508.
Zheng, L.; He, H.; Song, W. Application of light-emitting diodes and the effect of light quality on horticultural crops: a review. HortScience, 2019, 54, 1656–1661.
Paradiso, R.; Meinen, E.; Snel, J.F.; De Visser, P.; Van Ieperen, W.; Hogewoning, S.W.; Marcelis, L.F.M. Spectral dependence of photosynthesis and light absorptance in single leaves and canopy in rose. Sci Hortic, 2021, 127, 548–554.
Smith, H.L.; McAusland, L.; Murchie, E.H. Don’t ignore the green light: exploring diverse roles in plant pro-cesses. J Exp Bot, 2017, 68, 2099–2110.
- The introduction lacks an introduction to the impacts of different light qualities on Orchidaceae (or plants), or why do authors select Full spectrum, Deep red/white (DR/W) - Medium blue (MB), Deep red/white (DR/W) - Low blue (LB) for experiment?
Response: We have added relevant references to light sources to make it easier for readers to understand the impacts of different light qualities on Orchidaceae plants (Lines 123-130).
“In fact, it poses a challenge to select the most effective light spectrum for each species [17-18]. For example, red light impacts the development of the photosynthetic apparatus, and both red and blue lights are most efficiently utilized for photosynthesis [19]. Blue light affects stomatal opening, plant height, and chlorophyll biosynthesis, whereas far-red light promotes flowering in long-day plants, and the red/far-red ratio regulates stem elongation, branching, leaf expansion, and reproduction [10]. Lastly, green light facilitates long-term development and short-term acclimation to light conditions, thereby enhancing crop productivity and yield [20].”
- It was suggested to add the light spectrum of the LEDs used in the experiment.
Response: The light spectrum of the LEDs used in the experiment has been added to Section 2.2. Supplemental light treatment (SL) as suggested (Lines 191-207).
- Full spectrum (FS) LED (EL-B05L1200-DSM-D4890W, > 350 μmol s-1 at 30 cm, 400-700 nm, SOLIDLITE, Taipei, Taiwan) for 1 h (subsequently referred to as FS-1) and 2 h (subsequently referred to as FS-2);
- Deep red/white (DR/W) - Medium blue (MB) (Philips Green Power LED, Philips, The Netherlands), primary light colors being DR/W with typical PPFD 800 μmol s-1, power consumption 285W, 400-750 nm, and efficacy 2.8 μmol J-1, for 1 h (subse-quently referred to as MB-1) and 2 h (subsequently referred to as MB-2) period; and
- Deep red/white (DR/W) - Low blue (LB) (Philips Green Power LED, Philips, The Netherlands), primary light colors being DR/W with typical PPFD 800 μmol s-1, power consumption 275W, 350-750 nm, and efficacy 2.9 μmol J-1, for 1 h (subse-quently referred to as LB-1) and 2 h (subsequently referred to as LB-2).
- …….placed in a TDARES greenhouse under an 8 h photoperiod. How to control the photoperiod in a greenhouse, when is the experimental season? Please provide more details on the experiment details and the greenhouse used in the study.
Response: A simple greenhouse was utilized, employing black non-woven fabric to regulate the light. The addition of a light source aimed to enhance the yield and quality of Oncidium. Supplementary LED lighting intervals (S), applied daily, were conducted for either 1 hour (4:00-5:00 A.M., designated as S-1) or 2 hours (4:00-6:00 A.M., designated as S-2) from March to September, 2022 (lines 191- 194).
- why did the author set the mean photosynthetic daily light integral measured at each location ranged 300 to 400 μmol s-1?
Response: As previously stated, a straightforward greenhouse was employed, utilizing black non-woven fabric to regulate the light, with the intention of augmenting the yield and quality of Oncidium. Consequently, each light source treatment was predicated on 300 to 400 μmol s-1. Besides the amount of exposure, the light type and duration were also incorporated.
- Has the consistency of light intensity been maintained, and what is the light intensity? If not, it is the dual effect of light intensity and spectrum.
Response: As mentioned previously, we utilized a simple greenhouse and controlled the light using black non-woven fabric. Therefore, each light source treatment was based on 300 to 400 μmol s-1, and in addition to the amount of exposure, the type and duration of light were also considered. The new light source was introduced 1 hour (4:00-5:00 A.M., designated as S-1) or 2 hours (4:00-6:00 A.M., designated as S-1) before sunrise. This irradiation method ensures that there would be no effect of light intensity accumulation.
- No significant differences were observed in the effects of type of light source (T), supplemental light duration (S) in PL, however, significant differences were observed in their interaction (T×S) effects in Table 2. Please check the result or explain the possible reasons. Similar results are also found in Table 3 and Table 5, please check and confirm.
Response: Yes, indeed, no significant difference was noted in pseudobulb length (PL) between the individual light source (T) and supplemental light duration (S). We hypothesize that the factor influencing the amount of photosynthetic products accumulated by the plants was the duration of light exposure, whereas the factor affecting the flowering properties of the plants was the quality of light. Therefore, the combined effect of these two factors appeared to have clear benefits for Oncidium.
- The discussion seems insufficient and please explain possible reasons about the results.
Response: We have revised the Discussion in Lines 426- 451 and Lines 489- 506.
“Applying LED light enhanced the pseudobulb length (PL), pseudobulb width (PW), and pseudobulb thickness (PT), thereby facilitating acclimatization to the natural environment. Comprehending these morphological alterations allows the creation of models for optimal 'Honey Angel' (HA) processing times at various growth stages, tailored to meet distinct industry requirements.
Recent literature has extensively examined the impacts of LEDs on plant morphogenesis, indicating that blue light augments the count of axillary buds [18, 22-23]. Conversely, it impedes bud sprouting and intensifies apical dominance. Furthermore, the diminished bud outgrowth under blue light exposure underscores its role in particular photoreceptors and its function as a phytochrome antagonist. Sakurako et al. [24] elucidate that blue LEDs augment chlorophyll biosynthesis and stomatal opening, while Song et al. [25] indicate that they are favorable for Anthurium andreanum's shoot growth, dry matter accumulation, photosynthetic rate, soluble sugar, and antioxidant activity. Concurrently, studies by Izzo et al. [26] and Yousef et al. [27] demonstrate that a red and blue LED combination promotes tomato plant growth. Shin et al. [28] also observe that quality Orchidaceae Doritaenopsis plants result from in vitro culturing under a mix of blue and red LEDs. Additionally, Liu et al. [29] disclose that, compared to red LED, blue LED hinders Oncidium stem growth but enhances soluble protein levels in protocorm-like bodies (PLB) and leaves, implying blue light's benefits for protein synthesis. Also, blue LED treatment leads to a higher PLB percentage and a 1.5-fold increase in Dendrobium officinale shoots [30]. It also amplifies the regenerated shoot count from PLB in Cattleya intermedia x C. aurantiaca [31]. In this study, the MB-1, MB-2, and LB-2 treatments triggered specific responses to PL, PW, and PT at G2, respectively. This underlines the necessity to account for light duration and spectrum sensitivity when tailoring lighting protocols for commercial farms. Furthermore, if the growing stages' coverage is insufficient, additional supplemental light treatments would be requisite.”
“The initiation of flowering in the LB-2 treatment and controls occurred on 19 June and 21 July, respectively. Light, functioning as an environmental signal, is perceived by a companion detection system that orchestrates plant photomorphogenetic responses, including transitions between developmental stages. Photoreceptors receive light signals and modulate growth, differentiation, and metabolism. Flowering under MB light is intricate, involving interactions among photoreceptors, an endogenous circadian clock, and flowering genes [32]. During HA plant development, light influences pseudobulb elongation, leaf expansion, plant architecture, and ultimately, the transition to flowering. The interplay among these components remains ambiguous and warrants further investigation. Evaluating HA flower production and quality is crucial for assessing the economic viability of cultivation. Enhancing production and quality entails increasing the number of flowers per plant, pedicels (branches) per flower, and flower size or length. Spectral quality markedly impacts the plant growth period, pseudobulb leafing, flowering time, and flower characteristics. Hence, understanding these effects is pivotal for selecting light sources that promote prolonged flowering periods and high flower and pedicel production in HA. This enables commercial ornamental growers to establish artificial supplementary lighting intervals, ensuring year-round flowering and marketing of Oncidium species.”
- Are the selected indicators sufficient to characterize the growth status of plants.
Response: Yes, those selected indicators have been commonly used for assessing the pseudobulb growth and flowering quality of Oncidium.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
I have reviewed the research article titled "The Effects of Light Treatments on Growth and Flowering Characteristics of Oncidesa Gower Ramsey 'Honey Angel' at Different Growth Stages." Here are the suggested revisions:
Introduction:
Remove the repeated sentences: "Under sufficient light, orchid plants have short, plump stems, bright green leathery leaves and yellowing, stunting, and scorching plants. Under sufficient light, orchid plants have short, plump stems and bright green leathery leaves; under too much light, they are scorched, yellowed, and stunted."
Material and methods:
Continue! I think something is missing after comma in #1 and after and in #2
In 2.1. Plant materials and cultural practices
1. Growing stage 2 (G2): plants in the plantlet stage prior to unsheathing with vegeta- tive shoots 10~20 cm in height,
2. Growing stage 3 (G3): plants in a pseudobulb-mature stage having flower stalks 3-6 cm in length, and
In 2.4. Statistical Analysis
What do you mean by “S” here? Rewrite clearly
LED time (S, for 1 h and 2 h, and control for 2 h).
Figure 2:
In Figure 2, "A" image showed S1, S2, S3, while in the figure caption, you wrote G1, G2, G3. Please ensure consistency and explain in the caption what "A," "B," "C," and "D" mean in Figure 2.
Throughout the manuscript, decide whether you want to use S1, S2, S3 or G1, G2, G3, and maintain consistency.
2.4. Statistical Analysis:
Please clarify what "s" stands for in this sentence: "LED time (S, for 1 h and 2 h, and control for 2 h)."
Regarding the experimental design:
The statement, "were 4 × 3 × 2 with 5 replications and a total number of 105 pots," seems to have a discrepancy. To match the intended number of 105 pots, you may rewrite it as follows:
"The experimental design consisted of 4 treatments, 3 growth stages, and 2 supplemental light intervals, with 5 replications, resulting in a total of 105 pots."
These revisions should help clarify and improve the readability of your review for the research article.
Best of luck
Author Response
Introduction:
Remove the repeated sentences: "Under sufficient light, orchid plants have short, plump stems, bright green leathery leaves and yellowing, stunting, and scorching plants. Under sufficient light, orchid plants have short, plump stems and bright green leathery leaves; under too much light, they are scorched, yellowed, and stunted."
Response: The following sentence has been deleted.
“ Under sufficient light, orchid plants have short, plump stems, bright green leathery leaves and yellowing, stunting, and scorching plants.”
Material and methods:
Continue! I think something is missing after comma in #1 and after and in #2
In 2.1. Plant materials and cultural practices
- Growing stage 2 (G2): plants in the plantlet stage prior to unsheathing with vegetative shoots 10~20 cm in height,
- Growing stage 3 (G3): plants in a pseudobulb-mature stage having flower stalks 3-6 cm in length, and
Response: The order 1, 2, and 3 has been changed as (1), (2), and (3) for continue. (Lines 171-174)
In 2.4. Statistical Analysis
What do you mean by “S” here? Rewrite clearly
LED time (S, for 1 h and 2 h, and control for 2 h).
Response: The sentences have been revised as follows.
“The analysis was carried out using a completely randomized design with 35 plants (replicates) for each type of LED (control, FS, MB, and LB), each growing stage (G2, G3, and G4), and each supplementary LED time (code-named S, for 1 h and 2 h, and control for 2 h).” (Lines 259-262)
Figure 2:
In Figure 2, "A" image showed S1, S2, S3, while in the figure caption, you wrote G1, G2, G3. Please ensure consistency and explain in the caption what "A," "B," "C," and "D" mean in Figure 2.
Response: We have made amendments to Figure 2 and modified the accompanying description.
Figure 2. (A) Schematic illustration of the application of LEDs in different plant growing stages (G2, G3, and G4) in HA greenhouse culture. Daily supplemental LED lighting applied to plants was carried out for 1 h from 4:00 A.M to 5:00 A.M. or 2 h from 4:00 A.M to 6:00 A.M. from March 1, 2022, until cut flowers were harvested. When plants were 2 years old and 10~20 cm tall with 4 to 5 leaves, they had at least 2 pseudobulbs. Plants were divided into 3 groups (G2, G3, and G4) for each of six supplemental lighting treatments, 5 replicates of each treatment being arranged in a completely randomized design, for a total of 105 pots. (B~D) Three different types of LEDs were used: full spectrum (B), deep red/white type - medium blue (C), and deep red/white type - low blue (D).
Throughout the manuscript, decide whether you want to use S1, S2, S3 or G1, G2, G3, and maintain consistency.
Response: As mentioned above, the analysis was carried out using a completely randomized design with 35 plants for each type of LED, each growing stage (G2, G3, and G4), and each supplementary LED time (code-named S, for 1 h and 2 h, and control for 2 h).
Regarding the experimental design:
The statement, "were 4 × 3 × 2 with 5 replications and a total number of 105 pots," seems to have a discrepancy. To match the intended number of 105 pots, you may rewrite it as follows:
"The experimental design consisted of 4 treatments, 3 growth stages, and 2 supplemental light intervals, with 5 replications, resulting in a total of 105 pots."
Response: Thank you very much for your suggestion, and the revised sentence is shown below.
“The experimental design consisted of 4 treatments, 3 growth stages, and 2 supplemental light intervals, with 5 replications, resulting in a total of 105 pots." (Lines 262-263)
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Further explanation is needed for the treatment of light intensity. Instead of (or not just) the light intensity provided by a single lamp. （> 350 μmol s-1 in FS，or 800 μmol s-1 in DR/W-MB?）
Author Response
Further explanation is needed for the treatment of light intensity. Instead of (or not just) the light intensity provided by a single lamp. （> 350 μmol s-1 in FS，or 800 μmol s-1 in DR/W-MB?）
Response: Thank you very much for your comment. The treatment of light intensity was added to Section 2.2. Supplemental light treatment (SL) as suggested.
- Full spectrum (FS) LED (EL-B05L1200-DSM-D4890W, > 350 μmol m-2 s-1 at 30 cm, 400-700 nm, SOLIDLITE, Taipei, Taiwan) for 1 h (subsequently referred to as FS-1) and 2 h (subsequently referred to as FS-2);
- Deep red/white (DR/W) - Medium blue (MB) (Philips Green Power LED, Philips, The Netherlands), primary light colors being DR/W with typical PPFD 800 μmol m-2 s-1, power consumption 285W, 400-750 nm, and efficacy 2.8 μmol J-1, for 1 h (subse-quently referred to as MB-1) and 2 h (subsequently referred to as MB-2) period; and
- Deep red/white (DR/W) - Low blue (LB) (Philips Green Power LED, Philips, The Netherlands), primary light colors being DR/W with typical PPFD 800 μmol m-2 s-1, power consumption 275W, 350-750 nm, and efficacy 2.9 μmol J-1, for 1 h (subse-quently referred to as LB-1) and 2 h (subsequently referred to as LB-2).
Author Response File: Author Response.pdf
