Phenology-Informed Strategies for Climate-Resilient Peach Production: Shoot Growth, Leaf Fall, and Flowering of Two Low-Chill Cultivars in Humid Subtropical Central Taiwan
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. Line 99: '1.5–0.9–1.5' --> Does this refer to N, P, and K?
2. Line 102: '2.2. Shoot Growth Measurement' --> How many trees (units) were surveyed for each variety?
3. Lines 117-118: 'In Equations [1] and [2], --> In Equations (1) and (2) --> Modify the parentheses to avoid confusion with the cited references.
4. Line 127: '>20% of leaves had abscised, and the end of leaf fall was defined when >90%' --> How can we distinguish between 20% and 90%?
5. Line 213: 'AICc' --> What does it mean?
6. Line 214: 'while Logistic-4P fit 2023 best (Tables 1–2).' --> Logistic-4P only has data for 2023. Can we say that 2023 is the best year? Or are the results from several models only shown in the table?
7. Line 284: 'Chiling' --> Chilling
8. Table 7. --> I understand that this study calculated chilling units (CU) and growing degree hours (GDH). However, for example, are the chilling units (CU) calculated here based on 100% flowering or bud break? Or are they calculated based on the chilling units (CU) until bud break in natural conditions? In other words, I understand that weights are assigned to each temperature range when calculating chilling units (CU). However, I'm curious about the period over which these values ​​were calculated and what criteria were used to calculate them. A more detailed explanation would be helpful. This is because, even if a plant's cold storage requirements are met, bud break may not occur simply because the external temperature is not suitable, i.e., it may still be in the ecodormancy stage. For example, if the cold storage requirements for breaking endodormancy are already met in mid-January during the winter, but the external temperature is low at that time and bud break occurs in early March, the chill units for breaking dormancy at that time should be the accumulated value up to mid-January, not the chill units up to early March. Therefore, a more detailed and clear explanation is needed in the Materials and Methods, Results, and Discussion.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThis study has important value in the subtropical adaptation research of low cooling peach tree varieties, but there are the following issues:
Q1. Different varieties have different tree ages (4 years old for 'Ruby' and 9 years old for 'Red Bell'), and the sampling locations for proliferating buds are not described in detail, which may affect the comparison of growth potential. The author should provide comparative photos of the plants, branches, leaves, flowers, fruits, etc. of these two varieties.
Q2. The sample size of peach trees varies between different years (3-4 trees), and the sample size of peach branches varies from year to year (10 branches/tree in 2022, 15 branches/tree in 2023-2024), without providing sufficient reasons. In addition, due to different sample sizes, the length of the error line should be the standard error rather than the standard deviation (there is a lack of explanation for the error line in the legend).
Q3. Although the use of AICc standards was explained, there was no detailed explanation for why these four specific nonlinear models were chosen
Q4. Due to the use of "analyzing data separately each year and not treating the year as a fixed effect" (lines 169-172), this method limits the depth of analysis for cross year comparisons of different cold accumulation levels.
Q5. The letter "P" in the text, similar to "P<0.01", should be italicized. The Latin name in reference 18 did not pay attention to font capitalization. Please check the formatting of the entire text.
Although there is a quantitative description of the differences in flowering between the apical and basal buds, the physiological mechanism explanation is weak.
Q7. The applicability of Taiwan's low cooling demand model has not been fully discussed, and its universality in different subtropical regions is questionable, lacking in-depth analysis of the effectiveness of cooling demand under subtropical conditions
Q8. Research has been limited to flowering phenology and has not extended to economic traits such as fruit setting rate, yield, and quality.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThis manuscript has been revised to reflect the reviewer's comments and has been significantly improved in completeness.
Author Response
Comment: This manuscript has been revised to reflect the reviewer's comments and has been significantly improved in completeness.
Response: We sincerely thank the Reviewer for the positive assessment. We are pleased that the revisions have improved the completeness and clarity of the manuscript, and we appreciate the Reviewer’s constructive feedback throughout the review process.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors answered most of my doubts, but if they want to use the current manuscript title, they also need to provide the distribution of peach trees in subtropical regions and prove that Taiwan's climate can represent the typical climate of subtropical peach tree distribution. Otherwise, the title needs to be modified. In addition, the comparison with temperate chill models (e.g. Utah, Dynamic) is not significant, and it is recommended to compare with other subtropical regions suitable for planting peach trees. Finally, in reference 18, "Humulus lupulus l." should be changed to "Humulus lupulus L." It is recommended that authors thoroughly check the format and grammar of the manuscript.
Author Response
Comment: The authors answered most of my doubts, but if they want to use the current manuscript title, they also need to provide the distribution of peach trees in subtropical regions and prove that Taiwan's climate can represent the typical climate of subtropical peach tree distribution. Otherwise, the title needs to be modified. In addition, the comparison with temperate chill models (e.g. Utah, Dynamic) is not significant, and it is recommended to compare with other subtropical regions suitable for planting peach trees. Finally, in reference 18, "Humulus lupulus l." should be changed to "Humulus lupulus L." It is recommended that authors thoroughly check the format and grammar of the manuscript.
Response: We appreciate this important point. We have revised the Introduction to more clearly position central Taiwan within the global distribution of low-chill peach production (Lines 47–53). Specifically, we now (i) describe the humid subtropical climate (Köppen Cfa) of central Taiwan and explicitly note its similarity to other low-chill peach regions in Southeast Asia and South America, and (ii) cite Byrne (2005) to document the expansion of low-chill stone fruit breeding and production across humid subtropical regions, including Florida, southern China, Thailand, Brazil, and northern Australia. We also explicitly state that our site is treated as a representative humid subtropical low-chill system, while acknowledging climatic heterogeneity within the broader subtropical belt.
In addition, we have revised the manuscript title to localize the study context more clearly:“Phenology-Informed Strategies for Climate-Resilient Peach Production: Shoot Growth, Leaf Fall, and Flowering of Two Low-Chill Cultivars in Humid Subtropical Central Taiwan.”
We further expanded the description of the Taiwan low-chill model in the Materials and Methods (Lines 162–166), emphasizing that this model was developed from long-term peach phenology in Taiwan and has been validated under comparable mild-winter conditions. We now explicitly frame it as a regionally appropriate tool for low-chill systems rather than a universal replacement for temperate chill models (e.g., Utah or Dynamic). While a full numerical comparison of chill models is beyond the scope of this dataset, we believe the revised text now better clarifies its applicability and limitations under subtropical conditions.
Finally, we have carefully re-checked the manuscript for grammar, style, and consistency. Minor typographical and formatting issues (including spacing, capitalization, and species authority formatting) have been corrected throughout the main text and reference list.
We hope these revisions satisfactorily address the Reviewer’s remaining concerns and further improve the clarity and rigor of the manuscript.
