Field-Based Evaluation of Heat Tolerance in Sweet Cherry Rootstocks Reveals Integrated Morphological and Physiological Adaptation Mechanisms

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript presents a field-based evaluation of heat tolerance in sweet cherry rootstocks. It is integrating morphological, anatomical, physiological, and biochemical traits. Overall, the study addresses a relevant and timely topic, as high-temperature stress is becoming an important constraint for cherry production in many regions, especially in connection with global climate change.

I appreciate that the field-based approach is a strong aspect. Most previous studies relied on controlled environments only. The integration of multiple trait categories combined with multivariate analyses provides a comprehensive framework for evaluating rootstock performance and can be considered as a clear strength of the manuscript.

 

The experimental design is generally sound, and the selection of widely used rootstocks increases the practical relevance of the results and broader applicabiltity.

The conclusion statements are consistent with the presented results, and the ranking of rootstocks appears to be supported by the statistical analyses.

The manuscript is generally well written in most parts.

Hovewer, there ar several language issues and typographical inconsistencies, which should be corrected.

 

For example, in the Introduction, phrases such as “extremely heat days” should be corrected to “extremely hot days,”

 

Similarly “heat stress increasing induces” should be revised to “heat stress increasingly induces.”

 

In the Materials and Methods, “for the calculate of chlorophyll” should be corrected to “for the calculation of chlorophyll.”

 

There are also a few inconsistencies in abbreviations (e.g., RLN/RLE) that should be unified throughout the text and tables.

 

Additionally, in Table 3, there appears to be a formatting or typographical error in the value “`-0.25” for Principal component in F3 column, which should be corrected.

 

I would also strongly recommend a consistent typographical convention for rootstock names. In several places, apostrophes are used around rootstock names (e.g., ‘Gisela 6’, ‘Colt’). It would be preferable to avoid apostrophes above the rootstock names and instead use a consistent format without quotation marks. It is especially needed in tables, figures, and axis labels, to improve typographic clarity and readability.

 

The manuscript shows inconsistent use of abbreviated Latin names of botanical species; the format should be unified throughout the text according to standard botanical nomenclature.

 

Overall, the manuscript presents valuable field-based data and offers a useful integrative framework for evaluating heat tolerance in commercially important cherry rootstocks. With minor language corrections, consistent terminology, and improved typographic conventions, the manuscript would be suitable for publication.

Comments on the Quality of English Language

English needs minor corrections.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper examines how five sweet cherry rootstocks respond to heat stress, aiming to identify the most suitable one and reduce graft damage in a subtropical region.

The study is well-structured, thorough, and well-executed. I have a few minor suggestions for improvement. First, enhance the quality of the figures; they are currently low-resolution and difficult to interpret.

Line 146: It is important to specify how the sample was handled—whether it was frozen immediately or kept on ice until transport.

In Table 2 in LLN, what does the symbol 个 represent?

Figure 5 shows hormone contents in ng g^-1 (fw or dw?), and osmolyte concentrations in mg g^-1 (fw or dw?).

I recommend using temperature data to calculate degree days of development (DDD) to determine the tree’s phenological stage more objectively during the experiment, or alternatively, apply the BBCH scale to relate it to phenology (consider consulting https://doi.org/10.1016/j.ufug.2016.06.028 and https://doi.org/10.1016/j.scienta.2023.112711).

This approach will help confirm whether the trees are at the same developmental stage, which can inform on their resistance or susceptibility. Accurately determining the trees' developmental stages and confirming whether they are synchronized, an important factor influencing resistance or susceptibility, is crucial.

Finally, the conclusions seem somewhat premature; since the data are based on only one sampling point and one measurement of morphological and physiological parameters in September, it would be better to frame these conclusions within the context of the study's limitations.

Variables like these are highly sensitive to rapid changes, both biotic and abiotic, such as enzymatic activity and osmolyte concentration. Additionally, osmolytes can reflect other physiological responses related to water or cold stress.

Therefore, I believe this work discusses these aspects well, but further research with ongoing sampling is necessary to strengthen the findings.

There are errors in the references; check them.

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The article presented by the authors is timely and highly relevant in the context of currently observed climate change. This article may be of interest to both researchers and plant breeders.

However, before publishing this manuscript, I suggest making a few corrections:

1. The novelty of the work should be more clearly emphasized.
2. The descriptive sections of the results can be shortened (they are already presented in tables and figures). For example, the sections describing leaf appearance and disease infestation are very extensive.
3. The interpretation of MDA, CAT, and ABA should be clarified – a clear distinction should be made between "stress response" and "adaptation."
4. LD has high tolerance, while at the same time, it has a relatively high MDA. This should be further clarified.
5. I also suggest the authors thoroughly reread the manuscript to eliminate minor grammatical errors.

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.pdf