Wind-Induced Bending Characteristics of Crop Leaves and Their Potential Applications in Air-Assisted Spray Optimization

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

TITLE
 Suggestion: Wind-Induced Bending Characteristics in Crop Leaves.

ABSTRACT
 No suggestions for improvement.

KEYWORDS
 Highlight words that are not in the title and contribute to the identification of the article.

INTRODUCTION
 Present other similar published studies to support the discussion of the results.

MATERIALS AND METHODS
 The titles of tables and figures should be self-explanatory, for example: Table 1 – Yield components of wheat (Triticum aestivum), cultivar Texas™, controlled by fungicide application with and without adjuvants, 2024 harvest, Farm Sacramento (California – USA).
 How many replicates were performed?
 Were any experimental designs or statistical tests used?

RESULTS AND DISCUSSION
 Shouldn't the first paragraph be in the Materials and Methods chapter?

CONCLUSION
 No suggestions for improvements.

REFERENCES
 I suggest aligning the References with the journal's standards and checking that all citations in the text are in the references and vice versa.

The reviewer recommends accepting the article because the topic is interesting and well-written. There are doubts about whether statistical analysis can be applied, as at least 12 degrees of freedom in the residual are required.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper investigates bending deformation under wind load of walnut, peach and pepper influenced by wind speed, in a range of 2-12 m/s, which are typical values for wind conditions experienced by crop leaves during field spraying operations. The study is relevant for theoretical and practical studies related with the optimization of spraying parameters of spraying machines based on air-assisted technology in pesticide applications.

The main contribution of this study relates with quantitative analysis of wind-induced bending, from mechanical point of view, in order to emphasize the mechanisms behind non-uniform bending of crop leaves under wind-induced forces. Another key feature is the novel experimental approach, in which the leaves are analyzed in wind tunnel controlled environment, using high-speed photography and digital image analysis for in depth characterization of leaves curvature and flexibility.

Also, there are some weaknesses and methodological considerations to clarify:

Line 102: it is stated ‘’representing low flexibility (walnut), medium flexibility (peach), and high flexibility (chili 102 pepper) leaf types’’ – a classification/characterization of low/medium/high would be clearer;

Line 103: author does not mention the number of replicates or provide any statistical analysis means or methodology used;

Figure 1d: provide a clearer image; a short description of the three-point bending test would be suggested;

Equation1: how EI is determined and its unit of measurement;

Table 1, line 133: does not provide the flexural stiffness, bending stiffness is not defined, standard deviation and mean values are not computed;

Figure 2a: provide a clear image/schematic, together with the coordinate system;

Figure 3: provide the measurement scale and please identify the leaves and wind speeds

Lines 200-206, 468, 480: it’s useless to compare the leaves with different mechanical properties, the analysis should provide a clear understanding of mechanical behavior/aerodynamic response of each crop and how this is related with air-assisted pesticide application;

Figure 4: provide the scale for (a), it seems that it does not fit with (b,c,d)

Table 2 and lines 21-22: it is stated that ”The results indicate that both overall and local leaf curvatures increase significantly with rising wind speed” is not suported by the curvature results showed in table 2 and by missing statistical analysis (see column walnut), e.g. at speed 0 m/s the curvature is higher than at speed 3 m/s

Lines 474-477 and 484: provide the expected optimized wind speeds and spraying parameters to be used in order to improve pesticide droplet deposition and retention for analyzed crops.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript presents an experimental study on the wind-induced bending behavior of crop leaves, with implications for optimizing air-assisted spraying techniques. The topic is relevant to the scope of the journal and the special issue, combining plant biomechanics with practical applications in horticultural crop protection.

1. The title and keywords are generally consistent with the content of the abstract and reflect the core focus of the study, namely, the mechanical response of crop leaves to wind-induced bending. However, both the title and keywords could be slightly refined to better reflect the scope and practical implications of the work. For example, the title might benefit from emphasizing the experimental nature of the study and its relevance to spraying optimization. Additionally, the keywords could be expanded to include more technical and application-oriented terms such as leaf biomechanics, high-speed imaging, pesticide deposition, etc.
   These additions can enhance the discoverability and influence (and so, citation potential) of the article.
2. The introduction provides a clear and logical rationale for the study and effectively introduces the research topic.
3. Materials and Methods:
   1. The statement “These three types of leaves exhibit distinct differences in morphological structure and mechanical properties, representing low flexibility (walnut), medium flexibility (peach), and high flexibility (chili pepper) leaf types, respectively.” requires support from relevant literature.
   2. Equation 1 should also be referenced or justified with prior studies.
   3. The section lacks quantitative details about the experiment, such as the number of leaves tested per species. This omission makes it difficult to assess the robustness of the results and the validity of any statistical analysis which is not mentioned at all.  This is a key flaw in the work.
   4. Figure 1d should be presented as a separate figure with a clear legend and explanation of the experimental setup.
4. While the discussion is comprehensive, the reliability of the results is undermined by the absence of sample size information and statistical analysis. Without these, it is unclear e.g. whether the derived polynomial models are generalizable or suitable for future applications.
5. Figure 7 has an overly brief caption. Additionally, the phrase “across different segments” is unclear and should be clarified.
6. It is unclear why more detailed results are presented for walnut leaves compared to the other species. For example, there are no equivalents to Figure 5 for peach and pepper leaves, which raises questions about consistency in data presentation. In the context of the previously mentioned polynomials - if they were to be used in practice, why were they not given for these species?

Generally, the manuscript is quite interesting and relevant to the journal’s scope. With the suggested improvements, particularly regarding dataset transparency, statistical analysis, and figure consistency, it can be suitable for publication.

Comments on the Quality of English Language

There are minor language and formatting issues throughout the manuscript, such as inconsistent capitalization in Table 1/2, and typographical errors like “Imaje J”.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

After reading the revised manuscript, I can confirm that all of my concerns have been addressed satisfactorily. Thank you also for well-articulated responses. The revisions have significantly enhanced the quality of the work, and I see no obstacles to its publication in its current form.

The only remaining limitation is the lack of generalizability of the proposed polynomials. It would be worthwhile to explore this aspect in future research, and it could be briefly mentioned in the Discussion section.