Exogenous Cytokinins and Auxins Affect Double Cropping in Vitis vinifera L. cv. ‘Ortrugo’ Grown in a Temperate Climate: Preliminary Results

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Dear Editors and Authors,

I read with interest the manuscript entitled "Double Cropping Performances are affected by exogenous cytokinins and auxins applications in Vitis vinifera grown in a temperate climate". This research aims to evaluate the effects of exogenous application of 6-Benzyladenine (BA) and Naphthaleneacetic acid (NAA) influences dormant bud forcing at the excellent size stage and the vine's vegetative and productive performance in both primary and forced canopies, thereby contributing to the understanding of the physiology of pushing and double cropping in wine grapes under temperate climates. The article's subject is essential and relevant to the study area's scientific environment. Therefore, the manuscript needs some adjustments so that it can then be forwarded to the publication process. The manuscript has the potential for publication in the journal Horticulturae and requires the following adjustments:

TITLE
- Search for another term to replace "performance". Has this been evaluated? Review and decide whether to leave or not.

ABSTRACT
- Add information about the use of dormancy-breaking strategies. This will help us better understand the objective described.
- Add information about material and methods, such as variables analyzed, experimental design, and number of replicates.
- UC was abbreviated but was not described in the results. Remove abbreviation. Check this for all abbreviations mentioned here.
- Check all percentages. How can there be an increase more significant than 100%? Check and calculate again.

INTRODUCTION

- Line 32: Is double cropping a promising practice for all crops? Or just for grapes?
- Add more recent studies to enrich this section.
- Line 55: Did the research mentioned involve grapes?
- Line 70: The paragraph begins as if it were a continuation of the previous paragraph (Conversely,...). Correct.
- Add hypotheses before mentioning the objective.
- The objective needs to be reduced. See examples in articles in the area. The information must be clear for better understanding.

MATERIAL AND METHODS

- Was the planting system experienced?
- Add a figure with the climate data collected during the experiment.
- How was the daily evapotranspiration measured? Was a class-A tank installed? How was the amount of water applied during the day determined?
- Line 109: Was the total leaf area per plant not calculated? Why did they use the average leaf area?
- Line 122: assimilation of what?
- And the internal CO2 concentration was not measured? Why?
- Why were the measurements taken between 11 and 12 hours? Wouldn't that be a late time for these analyses?
- Was artificial light used for gas exchange analyses? How much?
- And the CO2 applied, was it ambient or controlled?
- How was the chlorophyll fluorescence measured? Was it done in the light or the dark? More details in another paragraph.
- Regarding the measurements of chlorophyll content, how was it done? How many leaves per plant were analyzed?
- In which part of the plant were the leaves used for these analyses? Middle, upper or lower third? Cite.
- Were all statistical analyses performed using SPSS?

RESULTS

- Line 171: "This section may be divided by subheadings. It should provide a concise and precise description of the experimental results, their interpretation, and the experimental conclusions that can be drawn."
Delete.
- Correct the citation of figures. The correct form would be "(Figure 1A)".
- When mentioning any result, a Figure or Table should be cited at the end of the excerpt. Review the entire text.
- I suggest adding column graphs with the results. This will help to visualize the results found better.

DISCUSSION

- Some information needs references.
The discussion should be related to the main results found. Some excerpts were mentioned but are not related to the study's results.
- Review the entire section.

 

CONCLUSIONS

- Line 346: What is correlative inhibition?

Author Response

I read with interest the manuscript entitled "Double Cropping Performances are affected by exogenous cytokinins and auxins applications in Vitis vinifera grown in a temperate climate". This research aims to evaluate the effects of exogenous application of 6-Benzyladenine (BA) and Naphthaleneacetic acid (NAA) influences dormant bud forcing at the excellent size stage and the vine's vegetative and productive performance in both primary and forced canopies, thereby contributing to the understanding of the physiology of pushing and double cropping in wine grapes under temperate climates. The article's subject is essential and relevant to the study area's scientific environment. Therefore, the manuscript needs some adjustments so that it can then be forwarded to the publication process. The manuscript has the potential for publication in the journal Horticulturae and requires the following adjustments:

Thank you for the review. We have addressed the required remarks to the best of our ability, responding to each point individually. The reviewer’s comments are referenced in the tracked revised manuscript by line number.

TITLE
- Search for another term to replace "performance". Has this been evaluated? Review and decide whether to leave or not.

We changed the title as suggested by Reviewer 2 and omitted performance. Thank you for the advice.

ABSTRACT
- Add information about the use of dormancy-breaking strategies. This will help us better understand the objective described.

We have added a sentence explaining dormancy-breaking strategies in our study (Lines 14–16, revised version).

Add information about material and methods, such as variables analyzed, experimental design, and number of replicates.

We added information on the evaluated parameters. However, details on the experimental design and number of replicates have been kept in the Materials and Methods section for clarity.

We integrated in the text some information regarding
- UC was abbreviated but was not described in the results. Remove abbreviation. Check this for all abbreviations mentioned here.

We removed (UC) and (CBA) in the abstract, following the reviewer’s suggestion.

- Check all percentages. How can there be an increase more significant than 100%? Check and calculate again.

The percentages are correct. They express the ratio between primary and forced shoots. In the case of FBA, forced shoots were more than primary ones. We revised adding “forced/primary shoots ratio” (line 25).

INTRODUCTION

- Line 32: Is double cropping a promising practice for all crops? Or just for grapes?

Our study focused on grapes, we revised adding “viticultural” in line 38 (revised version) to specify it. Additionally, grape quality was already mentioned in Line 39.

 
- Add more recent studies to enrich this section.

We included the most relevant references to the topic, among old and more recent publications.

- Line 55: Did the research mentioned involve grapes?

We clarified this point (line 65).

- Line 70: The paragraph begins as if it were a continuation of the previous paragraph (Conversely,...). Correct.

Thank you, we removed the line break.

- Add hypotheses before mentioning the objective.

We extended the sentence (line 79-80) to include the hypothesis.

- The objective needs to be reduced. See examples in articles in the area. The information must be clear for better understanding.

We shortened the objective by removing the last sentence and improving the overall flow (Lines 82–86).

MATERIAL AND METHODS

- Was the planting system experienced?

Thank you for the note, we added vine spacing (line 92 revised version).

- Add a figure with the climate data collected during the experiment.

We already presented climate data in Figure 1(A), showing minimum, mean, and maximum temperatures, rainfall, and growing degree day (GDD) accumulation.

- How was the daily evapotranspiration measured?

We provided this information in lines 100-102 and adapted the text accordingly.

Was a class-A tank installed? How was the amount of water applied during the day determined?

We added details on irrigation methods in Line 99.

- Line 109: Was the total leaf area per plant not calculated? Why did they use the average leaf area?

We estimated total leaf area by multiplying leaf number by average blade area (Lines 119–125 and 129–133). We added clarification in Line 126.

- Line 122: assimilation of what?

We specified “photosynthetic assimilation rate (A)” (line 135)

- And the internal CO2 concentration was not measured? Why?

In our study, we focused on CO₂ assimilation efficiency between the two canopy types, as our aim was to assess late-season photosynthesis.

- Why were the measurements taken between 11 and 12 hours? Wouldn't that be a late time for these analyses?

We selected this time to ensure adequate sunlight exposure to the canopy wall, as measurements were taken late in the season (September 20, 2024).

- Was artificial light used for gas exchange analyses? How much?

No artificial light was used. Gas exchanges were measured under natural sunlight with a PAR >1500 µmol m⁻² s⁻¹ (Line 138).

- And the CO2 applied, was it ambient or controlled?

We did not apply CO₂. We measured CO₂ assimilation under environmental conditions.

- How was the chlorophyll fluorescence measured? Was it done in the light or the dark? More details in another paragraph.

The chlorophyll fluorescence was measured after two hours of dark adaptation. We acknowledged this aspect in the revised version (Line 144).

- Regarding the measurements of chlorophyll content, how was it done? How many leaves per plant were analyzed?

We provided details in Lines 145–146 and specified that the same leaves used for chlorophyll fluorescence and gas exchange were analyzed (Lines 140–142).

 In which part of the plant were the leaves used for these analyses? Middle, upper or lower third? Cite.

We addressed this issue in the previous point.

- Were all statistical analyses performed using SPSS?

Correct, we clarified this by moving the information to the end of the section.

RESULTS

- Line 171: "This section may be divided by subheadings. It should provide a concise and precise description of the experimental results, their interpretation, and the experimental conclusions that can be drawn."
Delete.
Done.

- Correct the citation of figures. The correct form would be "(Figure 1A)".

We corrected figure citations consistently throughout the manuscript.

- When mentioning any result, a Figure or Table should be cited at the end of the excerpt. Review the entire text.

We added appropriate citations in the Results section.

- I suggest adding column graphs with the results. This will help to visualize the results found better.

Given the number of treatments and variables, we prefer to present results in tables.

DISCUSSION

- Some information needs references.

We incorporated additional citations.

The discussion should be related to the main results found. Some excerpts were mentioned but are not related to the study's results.

We revised the discussion to highlight the main findings.

- Review the entire section.

 The section has been revised, with added explanations where necessary.

CONCLUSIONS

- Line 346: What is correlative inhibition?

We explained dormancy and correlative inhibition in the introduction (line 51) providing reference [9]. We replaced correlative inhibition with the synonym paradormancy throughout the revised version.

Reviewer 2 Report

Comments and Suggestions for Authors

The review of the manuscript entitled „Double Cropping Performances are affected by exogenous cytokinins and auxins applications in Vitis vinifera grown in a temperate climate”

 

The authors of the submitted manuscript examine the possibility of double cropping in the cultivar Ortrugo (Vitis vinifera) grown in temperate climate conditions (Italy). Due to climate change, the possibility of harvesting twice in a season, as primary and forced yield - after breaking the dormancy of axillary (dormant) buds is interesting, and taking up the subject is justified.

The introduction contains essential information on the biology of the vines, the mechanism and practical methods of breaking the dormancy of the vine. The experimental design, the method of performing measurements, the statistical analysis of the results and their presentation are correct. The authors present detailed results on the vegetative growth, physiological status and yield of the vines, fruit composition, and single leaf gas exchange parameters.

The research was conducted for only one season and therefore the results should be considered preliminary. It is advisable for such information to be included in the title of the manuscript and commented on in the Discussion and possibly in the Conclusions section, where the scope of future research is indicated. Grapevine is a perennial plant, and is advisable for the authors to evaluate the cumulative yield from at least a 3-year period in the future study. The authors carried out pruning and applied plant growth regulators after dormant bud induction was completed, but the influence of forcing and application of growth regulators on bud actual fruitfulness in subsequent years cannot be ruled out. Summer pruning is an integral part of double cropping induction, as evidenced by the sentence “The removal of shoot tip combined with the application of BA leads to a significant increase in forced budburst and forced yield without affecting fruit composition compared to FR treatment” (l. 346-348). It is advisable for the title of the article to precisely define the scope of the research, especially since the title itself is also the main conclusion from the research. I suggest changing the title to one more appropriate to the content of the text, e.g. „Preliminary results on double cropping performances affected by summer pruning,  exogenous cytokinins and auxins applications in Vitis vinifera ‘Ortrugo’ (grown in a temperate climate)”

 

Detailed comments

Plants lack specialized organs for the secretion of hormones, therefore the term "hormones" in its strict and correct definition refers to the animal world. Regardless of this, authors often use the name hormones or phytohormones in reference to plants.

Considering the context of the article, however, I suggest changes:

1. 202-203 instead „exogenous hormonal applications” , rather „plant growth regulator applications”
2. 252 and 258 instead “phytohormones application”, rather „plant growth regulator applications”.

 

The proposed changes are optional. Regardless of the comments made, I rate the manuscript very positively and in my opinion, it can be the subject of further editorial work.

Author Response

Review report #2

The authors of the submitted manuscript examine the possibility of double cropping in the cultivar Ortrugo (Vitis vinifera) grown in temperate climate conditions (Italy). Due to climate change, the possibility of harvesting twice in a season, as primary and forced yield - after breaking the dormancy of axillary (dormant) buds is interesting, and taking up the subject is justified.

Thank you for the review. We appreciate the reviewer’s revisions and have done our best to address them.

The introduction contains essential information on the biology of the vines, the mechanism and practical methods of breaking the dormancy of the vine. The experimental design, the method of performing measurements, the statistical analysis of the results and their presentation are correct. The authors present detailed results on the vegetative growth, physiological status and yield of the vines, fruit composition, and single leaf gas exchange parameters.

Thank you for your positive evaluation of our work.

The research was conducted for only one season and therefore the results should be considered preliminary. It is advisable for such information to be included in the title of the manuscript and commented on in the Discussion and possibly in the Conclusions section, where the scope of future research is indicated.

We acknowledge this aspect and have incorporated a statement in the conclusion section.

Grapevine is a perennial plant, and is advisable for the authors to evaluate the cumulative yield from at least a 3-year period in the future study. The authors carried out pruning and applied plant growth regulators after dormant bud induction was completed, but the influence of forcing and application of growth regulators on bud actual fruitfulness in subsequent years cannot be ruled out. Summer pruning is an integral part of double cropping induction, as evidenced by the sentence “The removal of shoot tip combined with the application of BA leads to a significant increase in forced budburst and forced yield without affecting fruit composition compared to FR treatment” (l. 346-348).

Also the need for replication over multiple vintages has also been acknowledged in the conclusion.

 It is advisable for the title of the article to precisely define the scope of the research, especially since the title itself is also the main conclusion from the research. I suggest changing the title to one more appropriate to the content of the text, e.g. „Preliminary results on double cropping performances affected by summer pruning,  exogenous cytokinins and auxins applications in Vitis vinifera ‘Ortrugo’ (grown in a temperate climate)”

We have modified the manuscript title by rephrasing it and including 'preliminary results

Detailed comments

Plants lack specialized organs for the secretion of hormones, therefore the term "hormones" in its strict and correct definition refers to the animal world. Regardless of this, authors often use the name hormones or phytohormones in reference to plants.

We partially agree with reviewer 2, actually “hormone” is widely used in the plant world. We have replaced hormones with plant growth regulators since we applied synthetic phytohormones.

Considering the context of the article, however, I suggest changes:

1. 202-203 instead „exogenous hormonal applications” , rather „plant growth regulator applications”

Done, as suggested above 

1. 252 and 258 instead of “phytohormones application”, rather „plant growth regulator applications”.

 Done, as suggested above

The proposed changes are optional. Regardless of the comments made, I rate the manuscript very positively and in my opinion, it can be the subject of further editorial work.

Thank you for the suggestions. We have done our best to address all the issues presented.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript has been revised, but minor changes are needed.

Remove "preliminary results" from the title. This detracts from the importance of the research.

Line 131: Photosynthetic active reaction? What is this? Wouldn't it be photosynthetically active radiation or photosynthetically active flux density? Correct.
The value should be fixed. Generally, 1200 to 1500 µmol m-2 s-1 is used for C3 plants.

Author Response

Remove "preliminary results" from the title. This detracts from the importance of the research.

Thank you, we have added preliminary results based on the suggestion of Reviewer2.

Line 131: Photosynthetic active reaction? What is this? Wouldn't it be photosynthetically active radiation or photosynthetically active flux density? Correct.

Done, thank you.

The value should be fixed. Generally, 1200 to 1500 µmol m-2 s-1 is used for C3 plants.

We measured photosynthesis under natural sunlight conditions, as explained in the text. During the selected time window, the average PAR values exceeded 1500 μmol m^-² s^-1 , which we set as the threshold for gas exchange measurements. Thank to reviewer1 for further remarks.