The Selection of Lettuce Seedlings for Transplanting in a Plant Factory by a Non-Destructive Estimation of Leaf Area and Fresh Weight
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn the plant factory, the selection of uniform and healthy seedlings is directly related to later yield. This article investigates the potential of non-destructive image analysis for predicting lettuce growth, and confirms the correlation between projected canopy size (PCS) and leaf area or root fresh weight of lettuce. The following issues still need to be considered.
1. Leaf area and root fresh weight are important indicators of seedling growth parameters, and there are many studies that have shown their impact on final yield. The image-based PCS detection method can be considered as mainly detecting seedling leaf area. So, how does the novelty of this article reflect? Please help to answer.
2. There are many articles related to image-based plant phenotype detection, including the detection of different growth parameters of seedlings. It is suggested to add a description of the current research status in the Introduction to illustrate the significance of the research.
3. The author simplifies the Projected crop size to PCS in the keywords and line 70, but simplifies the projected canopy size to PCS in other sections. Please verify and revise.
4. Please add the meanings of Q4 and Q3 in line 146 to enhance the readability of the manuscript.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe paper investigated the prediction of the leaf area and shoot fresh weight parameters for lettuce using a non-destructive image analysis method. The paper’s topic matches the scope of the journal. To further improve the quality of the paper, the authors should consider the following comments.
1. Please add a literature review on the PCS measurement study in the introduction.
2. Please provide details on the hardware and software parameters used in the imaging system.
3. The leaves on the plants have different postures. What impact will different leaf postures have on the PCS calculation results?
4. Please replace some older literature.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsDear Editors and Authors, I read with interest the manuscript entitled “Selection of Lettuce Seedlings for Transplanting in a Plant Factory by Non-destructive Estimation of Leaf Area and Fresh Weight”. In this study, we measured the projected crop size (PCS) using a simple visual camera and investigated the correlation between PCS and the growth parameters measured destructively in lettuce seedlings. Following the grading of lettuce seedlings based on non-destructively measured PCS values, the yields of each grade of lettuce seedlings were monitored to ascertain the efficacy of image analysis at the time of transplanting in establishing healthy seedling standards that could ensure a certain level of yield.
The article is simple and not very new. There are other more robust studies confirming the growth estimation technique through image analysis, not only for lettuce but for all crops. What is new about the study? What criteria were adopted? Were models used for the estimation or not? Leaf area and fresh weight cannot be considered as the total growth of the plant. Other growth variables could have been used for this estimation work. The work needs to be greatly reformulated to be submitted again to this journal. I have added some suggestions to be made:
- These objectives are confusing. I suggest leaving only the first part. Growth was not estimated, only leaf area and fresh mass were used. Review.
- Describe more about the methods used.
- What criteria were adopted for estimation?
- Add more information about other studies that estimated plant growth based on parameters such as height, leaf area, and dry or fresh mass, among others. The authors described little information about this key point of the study.
- The objectives described in the last paragraph should be similar to those described in the Abstract. Correct. They are confusing.
- Insert hypotheses before mentioning the objectives.
- The materials and methods section should be more detailed. See examples in other articles in the area.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsWhat the author said in lines 89-90 of the article is not particularly relevant. There have been PCS studies on the entire growth cycle of lettuce [1], which have proven the value of PCS for lettuce growth. Therefore, the novelty of the article has not been well reflected.
[1] Jayalath, T. C. , & Van Iersel, M. W. . (2021). Canopy size and light use efficiency explain growth differences between lettuce and mizuna in vertical farms. Plants, 10(704), 704.
Author Response
Comment 1: What the author said in lines 89-90 of the article is not particularly relevant. There have been PCS studies on the entire growth cycle of lettuce [1], which have proven the value of PCS for lettuce growth. Therefore, the novelty of the article has not been well reflected.
Response 1: Thank you for pointing this out.
In [1], PCS measurements were taken at regular intervals from seeding to harvest, but only one set of destructive measurements of growth parameters was taken at the harvest time.
In our study, destructive growth measurements (leaf area, fresh weight) and PCS measurements were taken on a daily basis during the period of seedling production and on a weekly basis from transplanting to harvest time. We conducted PCS analysis in conjunction with destructive growth measurements periodically from seeding to harvest. And, we separated the nursery and cultivation stages, as is customary in commercial plant factories, and analyzed the correlation between PCS and growth at each stage. In particular, this is the first study to confirm the applicability of PCS as a criterion for selecting healthy seedlings by monitoring the lettuce growth and yield after transplanting to harvest.
We revised the sentences to avoid confusion and to show the novelty of our study according to what you commented (LL89-93). The revised sentences are shown in red color.
Reviewer 3 Report
Comments and Suggestions for AuthorsThe authors will review the manuscript and correct it according to your suggestions.
Author Response
Comment: The authors will review the manuscript and correct it according to your suggestions.
Response: Thank you.
Round 3
Reviewer 1 Report
Comments and Suggestions for AuthorsThere are some differences in the author's responses regarding the innovation points, whether it is the growth cycle or the detection method? It is recommended to condense and unify, and reflect it in the title, abstract, introduction, and discussion sections.
Author Response
Comment: There are some differences in the author's responses regarding the innovation points, whether it is the growth cycle or the detection method? It is recommended to condense and unify, and reflect it in the title, abstract, introduction, and discussion sections.
Response: Thanks for your comment.
Our innovation point is to select healthy seedlings that can yield adequate yields based on PCS values. Prior to achieving this objective, we conducted a comprehensive analysis of PCS values in conjunction with destructive measurement of growth at periodic intervals during the period of seedling production and cultivation after transplanting. This approach allowed us to assess the accuracy of PCS in reflecting the growth of lettuce from seeding to harvest time. We believe that our paper adequately addresses this aspect. However, in light of your valuable comment, we have revised the study's objectives to enhance clarity and avoid any potential misunderstandings (LL108-110). The modifications are marked in blue text.
