Effect of Nutrient Solution Activated with Non-Thermal Plasma on Growth and Quality of Baby Leaf Lettuce Grown Indoor in Aeroponics
, Giulia Carmassi, Damiano Lanza, Rita Maggini, Paolo Vernieri and Luca IncrocciRound 1
Reviewer 1 Report
Comments and Suggestions for AuthorsManuscript ID: agriculture-3404404
I have read the paper " Effect of nutrient solution activated with Non-Thermal Plasma on growth and quality of baby-leaf lettuce grown indoor in aeroponics.” which has been submitted to Agriculture. The study tray to develop a protocol for the application of non-thermal plasma to the nutrient solution in aeroponics, to produce baby-leaf lettuce indoor. The goal was to enhance the nutraceutical quality of the lettuce without reducing yield. Accurate knowledge of the appropriate dosage for various plasma applications is crucial to ensure their effectiveness and enhance their appeal for commercial use. Overall, it was written with clarity and precision, but needs some little corrections, which are suggested below:
1. Line 61: Please remove the spell checker message: “Fare clic o toccare qui per immettere il texto”
2. Line 82: It is better to use a more common unit: mS/m or S/m. These are more common units.
3. Lines 271-273: It is clear that there is a critical dose above which plasma does not stimulate plant growth. But what is this limit? Could you do this based on some parameter, and then compare it with other results in the literature? This study would be more valuable if you could discuss it based on some important parameters in the solution or in the plant, such as N, for example. You could compare these values with those in the literature.
Author Response
I have read the paper " Effect of nutrient solution activated with Non-Thermal Plasma on growth and quality of baby-leaf lettuce grown indoor in aeroponics.” which has been submitted to Agriculture. The study tray to develop a protocol for the application of non-thermal plasma to the nutrient solution in aeroponics, to produce baby-leaf lettuce indoor. The goal was to enhance the nutraceutical quality of the lettuce without reducing yield. Accurate knowledge of the appropriate dosage for various plasma applications is crucial to ensure their effectiveness and enhance their appeal for commercial use. Overall, it was written with clarity and precision, but needs some little corrections, which are suggested below:
- Line 61: Please remove the spell checker message: “Fare clic o toccare qui per immettere il texto”
Done.
- Line 82: It is better to use a more common unit: mS/m or S/m. These are more common units.
“mS/m” has been used.
- Lines 271-273: It is clear that there is a critical dose above which plasma does not stimulate plant growth. But what is this limit? Could you do this based on some parameter, and then compare it with other results in the literature? This study would be more valuable if you could discuss it based on some important parameters in the solution or in the plant, such as N, for example. You could compare these values with those in the literature.
Since the level of active species in NTP-activated water/solution is generally not reported in the literature, it is not easy to make this kind of comparison. Anyway, a comment on the toxicity of NTP has been added on lines 281-286.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe manuscript “Effect of nutrient solution activated with Non-Thermal Plasma on growth and quality of baby-leaf lettuce grown indoor in aeroponics” is aimed at investigating the possibility of cold atmospheric plasma treatment of liquids to have a beneficial effect to plants development. The non-thermal plasma applications, in agriculture presented in this work, is a distinctly up-to-date topic and a good approach for developing and implementing new plasma technologies in favour of plant growing. Undoubtedly, in the process of this research, the authors conducted a large-scale experiment that took a lot of time and equipment. Unfortunately, the presented manuscript does not present the obtained results fully and clearly. I believe that after revision this work could contribute to a better understanding of the effect of cold plasma application in hydroponic systems.
1. The reviewed references are not up-to-date considering the intensive development of plasma technologies in agronomy in recent years. This leads to a not particularly deep and sustainable motivation for conducting the study. The sources should be reviewed and the source edited.
2. The sequence of the experiment and the choice of its parameters remain unclear. The presence of a scheme of the experiment and the reasons for the choice of parameters would be beneficial for understanding.
3. The introduction of plasma as the main component of this study is incorrect. "Ionized gas" is not a complete definition of plasma, and it is also important that not only ionized gas enters the liquid from the plasma (line 76). Оn line 97 "tension" should be voltage. Please check carefully whether the operational frequency is really 50 Hz. Reading does not bring an understanding of what plasma is, about its operational parameters, and how plasma is applied in the experiment.
4. Тhe keywords need editing as they do not contain plasma or nutrient solution.
5. In Figure 2, the instantaneous drop in ORP after the end of the application of plasma-treated air is uncharacteristic, please explain.
6. The methodology for determining some of the plant parameters is described only briefly or not at all. How many plants are used to determine their characteristics and what was the procedure?
7. In Table 4 Carotenoids, Flavonoids, Phenols, Antioxidant and Nitrates capacity are not included. instead, they are only presented graphically. This makes it difficult to compare them with the tables from the previous two experiments.
8. The place of Table 5. „Composition of the nutrient solution at the end of the experiments“ in the discussion is not appropriate. The table should be introduced and discussed in detail in the results of the work. It would be good if the results in it were normalized between the three experiments for easier comparison.
9. Please check if all abbreviations are introduced in the text.
Author Response
The manuscript “Effect of nutrient solution activated with Non-Thermal Plasma on growth and quality of baby-leaf lettuce grown indoor in aeroponics” is aimed at investigating the possibility of cold atmospheric plasma treatment of liquids to have a beneficial effect to plants development. The non-thermal plasma applications, in agriculture presented in this work, is a distinctly up-to-date topic and a good approach for developing and implementing new plasma technologies in favour of plant growing. Undoubtedly, in the process of this research, the authors conducted a large-scale experiment that took a lot of time and equipment. Unfortunately, the presented manuscript does not present the obtained results fully and clearly. I believe that after revision this work could contribute to a better understanding of the effect of cold plasma application in hydroponic systems.
- The reviewed references are not up-to-date considering the intensive development of plasma technologies in agronomy in recent years. This leads to a not particularly deep and sustainable motivation for conducting the study. The sources should be reviewed and the source edited.
Some more recent references have been added in the Introduction.
Veerana, M., Mumtaz, S., Rana, J.N., Javed, R., Panngom, K., Ahmed, B., Akter, K., Choi, E.H., (2024). Recent Advances in Non-Thermal Plasma for Seed Germination, Plant Growth, and Secondary Metabolite Synthesis: A Promising Frontier for Sustainable Agriculture. Plasma Chem. Plasma Process. 44, 2263–2302. https://doi.org/10.1007/s11090-024-10510-7
Nikzadfar, M., Kazemi, A., Abooei, R., Abbaszadeh, R., Firouz, M.S., Akbarnia, A., Rashvand, M., (2024). Application of Cold Plasma Technology on the Postharvest Preservation of In-Packaged Fresh Fruit and Vegetables: Recent Challenges and Development. Food Bioprocess Technol. 17, 4473–4505. https://doi.org/10.1007/s11947-024-03380-6
Denoya, G.I., Szerman, N., Vaudagna, S.R., (2024). Application of Direct and Indirect Non-thermal Plasma in the Development of Ready-to-Eat Foods. Curr. Food Sci. Technol. Reports 2, 45–54. https://doi.org/10.1007/s43555-024-00018-8
Ranjitha Gracy, T.K., Sharanyakanth, P.S., Radhakrishnan, M., (2022). Non-thermal technologies: Solution for hazardous pesticides reduction in fruits and vegetables. Crit. Rev. Food Sci. Nutr. 62, 1782–1799. https://doi.org/10.1080/10408398.2020.1847029
- The sequence of the experiment and the choice of its parameters remain unclear. The presence of a scheme of the experiment and the reasons for the choice of parameters would be beneficial for understanding.
More information about the experiments has been added in lines 96-100. The treatments applied in each experiment are reported in Table 1.
- The introduction of plasma as the main component of this study is incorrect. "Ionized gas" is not a complete definition of plasma, and it is also important that not only ionized gas enters the liquid from the plasma (line76).
The definition of Non-Thermal Plasma in the introduction has been improved (lines 46-48).
Оn line 97 "tension" should be voltage.
Done
Please check carefully whether the operational frequency is really 50 Hz.
The operational frequency was 50 Hz.
Reading does not bring an understanding of what plasma is, its operational parameters, and how plasma is applied in the experiment.
This paragraph has been improved, and a scheme of the Non-Thermal Plasma generator has been added (Figure 1).
- Тhe keywords need editing as they do not contain plasma or nutrient solution.
"Nutrient solution" has been added as the keyword, while “plasma” is contained in the title.
- In Figure 2, the instantaneous drop in ORP after the end of the application of plasma-treated air is uncharacteristic, please explain.
These results have been obtained by measuring the ORP in the NTP-activated nutrient solution, and it is in agreement with the drop in O3 concentration. This rapid decrease in ORP could be due to the specific composition of the nutrient solution, characterized by a higher salt concentration than water.
- The methodology for determining some of the plant parameters is described only briefly or not at all. How many plants are used to determine their characteristics and what was the procedure?
The number of plants used for the determinations has been added at line 154.
More information about the methodology has been added in lines 159-174.
- In Table 4, Carotenoids, Flavonoids, Phenols, antioxidants, and Nitrates capacity are not included. instead, they are only presented graphically. This makes it difficult to compare them with the tables from the previous two experiments.
These results have been added to Table 5, and Figure 4 has been removed.
- The place of Table 5. „Composition of the nutrient solution at the end of the experiments in the discussion is not appropriate. The table should be introduced and discussed in detail in the results of the work. It would be good if the results were normalized between the three experiments for easier comparison.
The Table has been moved to the results, and normalized values have been added in brackets.
- Please check if all abbreviations are introduced in the text.
The text has been checked, and a few more abbreviations have been introduced.
Reviewer 3 Report
Comments and Suggestions for Authors1. Language issues occurred sometimes, such as in L61.
2. The NTP device and the working condition should be clearly demonstrated by figures, as well as its working diagram.
3. I don’t know how the authors got the O3 value as high as 80 mg/L (Fig.2) by using a measuring range of 0.010-4.00 mg/L test kit (L123).
4. Why the authors divided 0, 2.5, 5, 10, 25,50NTP into 3 experiments?
5. The fresh weight of each treatment should be showed clearly.
6. Why Fig.4 doesn’t have 25 and 50 NTP.
7. I don’t think it is appropriate and persuasive to explain the simple data in this study by using existing deeper research, if others had explained the effects of NTP on plants from mechanistic perspective, what’s the innovation and significance of this research.
Author Response
- Language issues occurred sometimes, such as in L61.
Corrected .
- The NTP device and the working condition should be clearly demonstrated by figures, as well as its working diagram.
The paragraph between lines 104 and 110 has been improved and a scheme of the Non-Thermal Plasma generator has been added (Figure 1).
- I don’t know how the authors got the O3value as high as 80 mg/L (Fig.2) by using a measuring range of 0.010-4.00 mg/L test kit (L123).
The O3 unit in the figure was wrong, and it has been corrected to µg L-1.
- Why the authors divided 0, 2.5, 5, 10, 25,50NTP into 3 experiments?
Information about the choice of treatments has been added at lines 96-100.
- The fresh weight of each treatment should be shown clearly.
The fresh weight of each treatment detected in each experiment is reported in Figure 3.
- Why Fig.4 doesn’t have 25 and 50 NTP.
Figure 4 has been removed according to the comment of another reviewer, and the results showed in Table 5. Anyway, 25 and 50 NTP treatments were not present since it showed only the results of Experiment 3.
- I don’t think it is appropriate and persuasive to explain the simple data in this study by using existing deeper research, if others had explained the effects of NTP on plants from mechanistic perspective, what’s the innovation and significance of this research.
This part of the Discussion has been shortened (Line 343-348), and some more information about the significance of the study has been added to the Conclusions.
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsI would like to thank the authors for the revisions.
Author Response
The authors thank the reviewer for his/her comment.
