Adding Phyto-LED Spectrum to White-LED Light Increases the Productivity of Lettuce Plants
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript studied the effects of Adding phyto-LED to white-LED on growth of lettuce.
There are some problems.
Line 20-21 ‘leaf plate area’ should be ‘leaf area’.
Line 34-35 what is ‘modern plant light culture’?
Line 58-59 what is ‘light culture conditions ’
Line 127 why do choose suitable light spectrum from the point of view of biotechnology or breeding?
Line 154 ‘ peduncles’ is not exact. Line 305 ‘peduncle germ ’?
Line 162 ‘ (Taiwan)’ is not in right place.
Line 188 ‘leaf camera’?
Line 226-228 ‘almost an average of 2 times’ is not exact value, there just 2 combination of phyto-LED and white-LED.
Line 296 what is ‘ light â„–1 and 2 ’
Line ‘it provoked accelerated flowering’ is not exact.
Line 365 why ‘ biological entities’ in here?
I do not think that ‘ L. sativa’is more suitable than lettuce in the manuscript.
There are many papers about the effects of green light and far red on plant growth, the discussion should discuss these results.
Author Response
Reviewer 1
We are grateful to the reviewer for his or her attentive attitude toward the manuscript and his time.
Comments 1: Line 20-21 ‘leaf plate area’ should be ‘leaf area’.
Response 1: We replaced "leaf plate area" with "leaf area’.
Comments 2: Line 34-35 what is ‘modern plant light culture’?
Response 2: We have replaced “modern plant light” with “current crop production”.
Comments 3: Line 58-59 what is ‘light culture conditions ’
Response 3: We have replaced “A spectral influence study on photosynthesis has shown that GL (green light) (500-600 nm) is less effective when growing plants on an industrial scale in light culture conditions since it is less absorbed by the chlorophylls of the main cells and, as a result, has less effect on plant productivity, unlike RL (red light) and BL (blue light)”, with “Some studies of the spectral effect on photosynthesis have shown that GL (green light) (500-600 nm) stimulates photosynthesis less effectively, since it is less absorbed by the chlorophylls of the main cells and, as a result, has less effect on plant productivity, unlike RL (red light) and BL (blue light)”.
Comments 4: Line 127 why do choose suitable light spectrum from the point of view of biotechnology or breeding?
Response 4: By useful use in breeding, we aimed to identify the most provocative spectrum for stimulating the flowering of plants. This spectrum could shorten the study period in which plants with the longest growing season were selected. After considering your comment, we decided not to mention its use in breeding, as this may mislead the reader, and for such statements, it would probably be necessary to perform a separate experiment.
We replaced “We assumed that by choosing a certain combination of white and Phyto LEDs, we can obtain various physiological and morphometric parameters, among which we can select the most interesting from the point of view of biotechnology or breeding”. We assumed that by choosing a certain combination of white and Phyto-LEDs, we can find such light spectra that can lead to an extension of the vegetative stage period and an increase in the rate of plant biomass recruitment; these spectrum options can be considered for practical use in crop production.
Comments 5: Line 154 ‘ peduncles’ is not exact. Line 305 ‘peduncle germ ’?
Response 5: We replaced “peduncles” with “peduncle germ”.
Comments 6: Line 162 ‘ (Taiwan)’ is not in right place.
Response 6: We replaced “Upr-Tek PG100N automatically calculated percentages of different light spectra (Taiwan)” with “Upr-Tek PG100N (Taiwan) automatically calculated percentages of different light spectra”.
Comments 7:Line 188 ‘leaf camera’?
Response 7: This has been done.
Comments 8: Line 226-228 ‘almost an average of 2 times’ is not exact value, there just 2 combination of phyto-LED and white-LED
Response 8: At 6500 K, the percentage of green colour was 42%, and when the Phyto-LED spectrum was added to this spectrum, the percentage of green colour was 24% (42%/24% = 1,75). At 2700K, the percentage of green colour was 49%, and when the Phyto-LED spectrum was added to this spectrum, the percentage of green spectrum was 28% (49%/28% = 1.75). Thus, the decrease in both cases occurred 1.75 times.
After recalculation, we found an error, recalculated all the ratios again and indicated the changes for both 2700K and 6500K separately.
Replaced “A decrease in the proportion of GL by almost an average of 2 times” with “A decrease in the proportion of GL by almost an average of 1.75 times for 6500K and 2700K”.
Replaced “An increase in the proportion of RL in the spectrum by an average of 1.5 times” with “An increase in the proportion of RL in the spectrum by an average of 1.85 times for 6500K and 1.23 times for 2700K”.
Replaced “An increase in the far-red by an average of 3 times” with “An increase in the proportion of FRL in the spectrum by an average of 3.5 times for 6500K and 2.3 times for 2700K”.
Comments 9: Line 296 what is ‘ light â„–1 and 2
Response 9: We replaced “light â„–1 and 2” with “6500K and 2700K”
Comments 10: Line ‘it provoked accelerated flowering’ is not exact.
Comments: Line 322
Response 10: This has been done. We replaced “it provoked accelerated flowering” with “stimulates the formation of a peduncle germ”.
Comments 11:Line 365 why ‘ biological entities’ in here?
Response 11: This has been done. Replacing “entities” with “objects”
Comments 12:I do not think that ‘ L. sativa’is more suitable than lettuce in the manuscript.
Response 12: Replaced “L. sativa” with “lettuce” when we mentioned the plants from our experiment.
Comments 13: There are many papers about the effects of green light and far red on plant growth, the discussion should discuss these results.
Response 13: We added discussion about the effects of green light and far red on plant growth
Reviewer 2 Report
Comments and Suggestions for AuthorsManuscript entitled “Adding Phyto-LED Spectrum to White-LED Light Increase the Productivity of Lactuca sativa Plants” by Vereshchagin M, Pashkovskiy P and Tarakanov I, is a study in which LED light sources that produce white light of different temperatures (K0) are compared for their effects on growth parameters of letuce cultured in a hydroponic system.
Authors measured changes in leaf area, fresh and dry mass, rate of photosynthesis, rate of transpiration, chlorophyll A content, total chlorophyll content, and flower bud formation in lettuce variety Batavia.
All three investigate LED light sources were manufactured by Epistar Technology, Taiwan comprising cool white light 65000K, warm white light 27000L and a special phyto-LED white light with dominant red, moderate blue and little presence of green light. Some treatment were combination of the three metioned light sources.
Authors concluded that phyto-LED light produced specifically to support plant growth, was somewhat (but not much) better when compared with the two other white light LED sources, pointing at importance of light spectral composition on Lactuca development . However, by combining white LEDs and Phyto-LEDs (2700K + Phyto LED) optimal light for growing L.sativa was achieved. They actually showed that a wider light specter is benefitiall for growing Lactuca.
I consider presented results as very important, coming after a thorough, well planed, well prepared and well executed study. Overall, this is an excelent study which I recommend to be published at once. Above all, manuscript is written in excellent language, enabling easy flow of results and conclusions, which together with illustrations provide additional value to this study.
There is a reason why the output of light in the solar radiation is so strong in the yellow and orange parts of specter (not presented in light specters in your studies). Nothing spectacular results from their presence, but yellow and orange light together with green, probably keep the blue, red and far red light in check, buffering somewhat their otherwise extraordinary effects.
Rev
Author Response
Dear Reviewer,
Thank you very much for your thorough and positive review of our manuscript. We appreciate your detailed summary and thoughtful analysis of our study.
Answer: Regarding your point about the role of yellow and orange light in the solar spectrum, we acknowledge the importance of these wavelengths in natural sunlight and their potential buffering effects on other light spectra. In our study, we focused on evaluating the impact of specific LED light spectra, including phyto-LEDs, which are designed to enhance plant growth by optimizing red and blue light exposure. We aimed to assess how these spectra influence the growth parameters of Lactuca sativa under controlled hydroponic conditions.
While our study did not include the direct influence of yellow and orange light, we recognize that incorporating a wider range of wavelengths, including these, could provide further insights into optimizing artificial light sources for plant growth. Future research could explore the potential synergistic effects of integrating yellow and orange light with the spectra we studied to better simulate natural sunlight and possibly enhance the growth and development of L. sativa even further.
Thank you again for your valuable feedback and for recommending our manuscript for publication.
Reviewer 3 Report
Comments and Suggestions for AuthorsThe study aims to explore the increasing Productivity of Lactuca sativa Plants by adding Phyto-LED spectrum to white-LED Light. However, there is key problem should be addressed. The most critical problem is that authors should indicates first that do all the combination of LEDs are the same power. If not, the study will be meaningless, because famers do care about the cost and high cost will be unacceptable even the combination brings small ratio of high yield. Meanwhile, authors should indicate the cost-yield relationships by connecting the power with yield to reveal that the high yield is obtained at low power cost. Besides, there are lots of writing problems need to be revised.
In Abstract, the first appearance of abbreviation should be defined.
L64. “white LED polychromatic LEDs”?
L94. It is unacceptable for Fig 2 appeared first. It should always be Figure 1 appeared first. Besides, both Figure 2 and Fig 2 are used in the manuscript, which is now allowed.
L107. Please improve the sentence.
L181, L185. “n” seems different.
L196. What dose “chl an” represent for. Improve it.
L215. For statistic, p should be italic. Thoroughly check.
Author Response
I would like to express my deep gratitude to the Reviewer for carefully reading the entire text of the article and for his attentive comments. I also think that the reviewer is correct that he believes that adding such a parameter as the cost of lighting a square meter of area will add even more value to this article (data added).
Comments 1:This study aimed to explore the increasing productivity of L. sativa plants by adding a Phyto-LED spectrum to white-LED light. However, key problems should be addressed. The most critical problem is that authors should indicates first that do all the combination of LEDs are the same power. If not, the study will be meaningless because famers do care about the cost, and a high cost will be unacceptable even if the combination results in a small ratio of high yield. Meanwhile, authors should indicate the cost-yield relationships by connecting the power with yield to reveal that the high yield is obtained at low power cost. In addition, there are many writing problems that need to be addressed.
Response 1: We added data about the electric power of LED matrices , which provides a photon flux density of 170 µmol (photons) m-2 s-1 per 1 square meter of chamber in the phytotron for growing plants at a distance of 55 cm from plants. This information will be enough for anyone to calculate the cost of their project based on the cost of rental space, logistics, the price of final products, the cost of electricity and other costs.
Comments 2:In Abstract, the first appearance of abbreviation should be defined.
Response 2: This has been done. We replaced "GL" and "FRL" with "green light" and "high red light".
Comments 3:L64. “white LED polychromatic LEDs”?
Response 3: This has been done. We replaced “white LED polychromatic LEDs” with “white polychromatic LEDs”.
Comments 4:L94. It is unacceptable for Fig 2 to appear first. It should always be Figure 1 appeared first. In addition, both Figure 2 and Fig 2 have been included in the manuscript.
Response 4: This has been done. Figure 1 and Figure 2 were replaced, and the references were swapped to Fig 1 and Fig 2 in the text.
Comments 5:L107. Please improve the sentence.
Response 5: This has been done. Replaced “These differences are prepares a fairly strong basis for morphological and physiological differences in plants when parallel comparison of identical crops grown under given spectral conditions, all other things being equal” with “These differences can cause significant morphological and physiological differences in the plant”.
Comments 6:L181, L185. “n” seems different.
Response 6: This has been done.
Comments 7:L196. What dose “chl an” represent for. Improve it.
Response 7: This has been done. Replacing “an” with “a”
Comments 8:L215. For statistic, p should be italic. Thoroughly check.
Response 8: This has been done. We made all the "p" in italics.
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsLine 11 what do ‘Spectral composition Phyto-LEDs ’ mean?
Line 15 ‘pure Phyto-LEDs spectrum’? It should be ‘sole Phyto-LEDs spectrum’.
Line 18 ‘under hydroponic culture conditions’ should be ‘in hydroponic’.
Line 40 ‘with the help of basic photoreceptors ’ should be ‘by photoreceptors’.
Line 42 and 48 ‘circadian rhythms’‘the duration of the day and night’
Line 55-56 ‘Lengthening the growing season and increasing plant productivity are important objectives in applied plant physiology’
Line 59 ‘the main cells ’
Line72-73 ‘ on white fluorescent light’ ‘on different combinations’, ‘on’ should be ‘under’.
Line 88 ‘light recipe’ is rather than‘ light menus ’.
Line 189 ‘ per 1 square meter’ is redundant.
Line 264 272 ‘ Phyto-LED light Phyto-LED ’?
Table1 the data of photosynthetic rate is lack, while in Table 2.
Table 3 how to measure ‘stem length’?
Line 323-324 ‘ total area of plant leaves’ and ‘total area of leaves of plants’ should be ‘total leaf area’.
I do not think that ‘ L. sativa’is more suitable than lettuce in the manuscript.
Author Response
- Line 11 what do ‘Spectral composition Phyto-LEDs ’ mean?
Answer: We replaced “Spectral composition Phyto-LEDs” with “Phyto-LEDs spectrum”.
- Line 15 ‘pure Phyto-LEDs spectrum’? It should be ‘sole Phyto-LEDs spectrum’.
Answer: We replaced “pure Phyto-LEDs spectrum” with “sole Phyto-LEDs spectrum”.
- Line 18 ‘under hydroponic culture conditions’ should be ‘in hydroponic’.
Answer: We replaced “under hydroponic culture conditions” with “in hydroponic culture”
- Line 40 ‘with the help of basic photoreceptors ’ should be ‘by photoreceptors’.
Answer: We replaced “with the help of basic photoreceptors” with “with photoreceptors”.
- Line 42 and 48 ‘circadian rhythms’‘the duration of the day and night’
Answer: We improved the paragraph “Photoreceptors play a crucial role in regulating circadian rhythms by interacting with a complex of transcription factors, such as PIF, FT, and CO. This interaction enables plants to adapt their transition from the vegetative to the generative stage of development in accordance with the seasonal rhythms of their environment [5]. During the generative phase, the apical meristem of the plant shoot stops forming leaves and lateral shoots and starts producing generative organs. In addition to the spectral composition of light, factors such as day and night length, as well as endogenous factors such as plant age and water status, can also induce the transition to the generative phase of development. »
- Line 55-56 ‘Lengthening the growing season and increasing plant productivity are important objectives in applied plant physiology’
Answer: We have removed this sentence.
- Line 59 ‘the main cells ’
Answer: We have removed “the main cells”.
- Line72-73 ‘on white fluorescent light’ ‘on different combinations’, ‘on’ should be ‘under’.
Answer: We replaced “on” with “under”
- Line 88 ‘light recipe’ is rather than‘ light menus ’.
Answer: We agree that this was done
- Line 189 ‘ per 1 square meter’ is redundant.
Answer: We have removed “per 1 square meter”.
- Line 264 272 ‘ Phyto-LED light Phyto-LED ’?
Answer: We replaced “Phyto-LED light Phyto-LED” with “Phyto-LED light”.
- Table 1 the data of photosynthetic rate is lack, while in Table 2.
Answer: We have removed “photosynthetic rate (Pn, µmol/m2 s)” from Table 1.
- Table 3 how to measure ‘stem length’?
Answer: We added “The roots of each plant were removed to measure the fresh and dry mass of the roots. The leaves were separated from the stem. The length of the stem was measured from the base of the stem to the apex. Fresh leaves were counted for each plant, and the fresh weight, total leaf area, length and width of the largest leaf were measured. The leaves were then dried and weighed to obtain the dry mass of the leaves.”
- Line 323-324 ‘ total area of plant leaves’ and ‘total area of leaves of plants’ should be ‘total leaf area’.
Answer: We replaced ‘total area of plant leaves’ and ‘total area of leaves of plants’ with “total leaf area”.
- I do not think that ‘ L. sativa’is more suitable than lettuce in the manuscript.
Answer: We have corrected wherever our research was mentioned, but we have kept the names where the studies of other authors were cited, since the Latin name is indicated there
Reviewer 3 Report
Comments and Suggestions for AuthorsMost of my concerns have been addressed. However, the most important concern was not. Authors reply that “This information will be enough for anyone to calculate the cost of their project based on the cost of rental space, logistics, the price of final products, the cost of electricity and other costs”. Actually, it will be better that if authors could compare the cost according to the design of this study to uncover the economic concerns in results or discussion part.
Author Response
Dear Reviewer,
Thank you for being so attentive to our manuscript. We share your concerns about the economic aspect of our experiments. Unfortunately, we cannot provide accurate cost information in different countries, as prices for LEDs, fertilizers and other inputs vary significantly by region. Our work focuses on biological research at the interface of basic and applied sciences, and economic analysis is outside our area of expertise. We hope that our data and findings will be useful for future research and development in this area.
Despite this, we tried to improve the manuscript and added to the discussion the paragraph “Given the significant share of energy costs consumed by lighting fixtures, reducing these costs is an important goal. This problem must be considered using data such as the energy consumption of lighting fixtures and the rate of biomass gain of plants grown under different types of lighting. For example, based on the data presented in Figure 3, we can conclude that compared with Phyto-LED and 2700K + Phyto-LED lighting, 6500K lighting is the most energy efficient, saving approximately 25% of the total energy. However, it should be noted that plants grown under Phyto-LED and 2700K + Phyto-LED lighting had 50% and 40% greater fresh weight, respectively, than those grown under 6500K lighting (Table 1). The growth rate of plants grown under 6500 K + Phyto-LED lighting was intermediate between that under 6500 K and 2700 K + Phyto-LED lighting, but plants grown under this lighting had the same biomass growth rate as those grown under Phyto-LED lighting . Based on research data on energy consumption and biomass growth rate, the 6500K + Phyto-LED option appears to be the best in terms of productivity.
Thus, reducing energy costs when lighting plants requires an integrated approach that takes into account not only the efficiency of energy consumption but also the impact on the morphological and physiological characteristics of plants, such as stem length and the speed of transition to flowering.”
Round 3
Reviewer 1 Report
Comments and Suggestions for Authors
