Characterisation of Breadfruit (Artocarpus altilis) Plants Growing on Lakoocha (A. lakoocha) Rootstocks
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
The manuscript bridges the author's previous research work, so some essential content is omitted in the manuscript. Some of the omitted content is important and I think the author should make appropriate additions in order to increase the readability of the article.
Some figures and tables in the manuscript should appear in appropriate places to improve the logic of the manuscript.
Abstract
1. There are many sentences in the abstract stating the background of the research, but the description of the purpose and meaning of the research is lacking.
2. What does "Higher sucrose level in scion stems, and higher starch level in roots" indicate? Is it to express to promote production?
3. I don't understand why both "," and ";" are present in the keyword.
Introduction
4. Line 45： The "," should be remove .
5. The benefits and advantages of dwarfing should be added in the introduction, in order to highlight the purpose and significance of this study.
6. Is dwarfing to increase yield, is it an advantage. I think the statement should be made accordingly.
7. What does "Non-structural carbohydrate profiles" indicate, and what properties does it characterize in plants?
Materials and Methods
8. Section 2.1: Have these plants been grown in the laboratory, and have the growth conditions been set with reference to the natural environment?
9. Line 86: Why is the time point of "Assessment of graft compatibility" "12 and 21 months after grafting", and what are the special meanings of these two times for plant growth.
10. Line 103: The extraction and measurement method of "Glucose, fructose and sucrose, and starch" should be described in detail.
11. Lines 115 and 120: Sentences should be indented the appropriate distance to be consistent with the rest of the passage.
Result
12. Lines 115 and 119 of “Figure S2” appear in Figure 1 of Ref. 13, and such a description is confusing. If the corresponding content needs to be stated, it is necessary for the corresponding picture to appear in the article.
13. Line 123: The space before the % should be removed.
14. Line 133: There should be a space after "table", please check the manuscript for a similar place.
15. Table 1 should appear in Section 3.1, in order to improve the readability of the article.
16. Figure 2: It would be nice to provide this raw data from five biological replicates.
17. Line 175: "1" should be followed by ".".
18. There are many "a" and "b" in Table 1, and their meaning should be explained.
Discussion
19. The author has fully discussed the research content of this paper. However, some of the references have been published for a long time, and some new publications should be referenced.
20. Line 229, "In this context" should be preceded by a space, there are many such errors in the manuscript.
21. Conclusions in the Discussion should be moved to the appropriate section in order to directly state the conclusions of this study.
22. In addition, the format of the references must be consistent.
Author Response
Please see attachment
Author Response File: 
Author Response.docx
Reviewer 2 Report
The manuscript is well written and the flow of thought is easily understandable. The article contains a new information on the grafting of breadfruit which is usually 15-30 m tall. Using lakoocha as rootstock and breadfruit as scion, the author can reduce the height of the breadfruit (dwarf; 32% shorter). The author confirms that the finding will provide information on the opportunity to design rootstock for breeding program. Nonetheless, the minor revision is necessary. Abstract needs short description of method in this study to provide the abstract as stand-alone complete IMRAD. The references in introduction are mostly out of date, so newer publication should be added. The methodology is lack of information on the design of the study, replications, etc. (see attachment), so detailed description is compulsory to make the method reproducible. Moreover, authors used 38 references, but 25 of them (65.8%) were out of date (more than 10 years). Addition of newer references is necessary to make state of the art of the article improved.
Comments for author File: 
Comments.pdf
Author Response
Please see attachment
Author Response File: Author Response.docx
Reviewer 3 Report
General comments:
The manuscript deals with the first report assessing the effectiveness of dwarf type lakoocha as a rootstock for grafting the vigorous growing breadfruit scion performance based on measured vegetative growth (stem thickness, internodal length, branch nos., leaf parameters, etc.), chlorophyll and carbohydrate contents of grafted and non-grafted plants. However, in my opinion, the findings were not well taken to reach a logical conclusion in the right way. It seems that the resulting dwarfing phenotype of grafted plant, ascertained by various parameters (e.g., thinner rootstock stem than scion stem), is rather indicative of graft incompatibility. Hence, authors need to provide possible justification supported by the earlier findings on the issue pointed out and if they still believe that dwarfing ness is not an inverted bottleneck and is acceptable at a commercial scale. Otherwise, they should revise the MS by presenting the results as such and concluding that a thinner rootstock stem indicates some kind of incompatibility (e.g., inverted bottleneck), so it needs further verification in actual field conditions for their effectiveness to produce satisfactory yields at commercial scale.
Specific comments:
Abstract:
Line 13: Insert comma (,) after here
Line 15: ‘composite tree’: mention that you call grafted tree a composite tree
Line 16-20: As stated above, one of the main aims of the study is to induce dwarfing ness in breadfruit trees to withstand a rising problem of windstorm and high-density planting. Hence, a strong base provided by rootstocks is needed to support the scion’s vigor. So, it is doubtful if the thinner stem girth (or decreased stem thickness) of rootstock (than control plants) can provide enough support under such adverse situations. Moreover, it is clear from the data showing thinner rootstock girth than scion girth that the dwarfing phenotype of a grafted tree (with reduced branches and leaves) is seemingly the result of an inverted bottle neck, attributing to the limited flow of water and nutrients through graft union due to poor anatomical compatibility. In long run, such grafts are considered to be incompatible with commercial yields.
Therefore, I would suggest redirecting your conclusion by saying the performance of breadfruit growth was assessed on lakoocha for the first time, and dwarfness in tree vigor of breadfruit was investigated to be due to inverted bottleneck rather than it was rootstock induced changes in tree vigor (as indicated by lesser rootstock stem thickness than control trees).
Line 20-22: Non-structural carbohydrate analysis: the relevance of the same needs to be linked or stated.
Keyword: Avoid repetition of words already reported in the title.
Introduction:
Line 35: ‘Recent tree loss from tropical windstorm’: this needs to be detailed for readers better understand the issues due to the storm.
Line 42: Please refer to an important and relevant paper by Gora et al. 2021, who have demonstrated dwarfing in ‘Fremont’ mandarin on ‘Pectinifera’ rootstock was caused by intrinsic features of the rootstock rather than an incompatibility reaction (https://doi.org/10.1016/j.sajb.2021.08.037).
Line 49: What was the mechanism of marang (A. odoratissimus) rootstock induced dwarfness in breadfruit scion, it needs to be highlighted.
Line 62: success in generating the composite trees: I would suggest redirecting your hypothesis based on the objective to assess the response of lakoocha as a rootstock for grafting breadfruit which induces dwarfing ness and study the mechanism of dwarfing ness which was mainly ascribed to inverted bottleneck rather than only rootstock induced control in vigor because a positive sign of dwarfing ness provided by rootstocks include stem thickening with reduced internodal length in rootstock and also to the scion as expected to be linked to some hormonal changes among other causes.
Materials & Methods:
Line 95: atLeaf: correct it.
Lime 101: Stem tissues were sampled at the second internode: from top or bottom?
Line 104: Stem and root
Results
Line 115: As it is the first time, one may like to know how much graft success percent in this graft combination.
Line 123: How non-grafted (control) plant was prepared so as to attain uniform (match) growth as was in self-grafted plants or vice-versa?
Line 131: across different rootstock
ks: there are just two rootstocks so accordingly revise the statement.
Line 143: both grafted and self-grafted plants instead of all grafted plants
Line 161-164: Photographs were not taken well: there is shade in the first (1-a) and angle issue in the second one (1-b). The stem thickness of scion and control plants looks similar so it is clear that the rootstock stem is thinner which is undesirable for envisaging a strong framework of a tree. Accordingly, the graft union seems like an inverted bottleneck condition with a huge difference; is it the compatible level?
Line 176: Grafting cause a type of physiological stress thus plant growth is arrested for a while, but I can see there is more plant height in the self-grafted plant, though no statistical difference, than in non-grafted ones. Explain it, why is it so?
Line 184: Explain why there is an opposite trend in chlorophyll with respect to grafted and control plants almost at each point of analysis….even consistency between self-grafted and non-grafted seedling plants is not there, showing the opposite trend. What do you want to show from this?
Discussion:
Line 214-215: This should be really the thrust of the study: ‘Breadfruit scions were successfully grafted onto lakoocha rootstocks, and the phenotype of the composite plants was for the first time characterized. As expected from the lakoocha species being a smaller tree in nature [17, 18], breadfruit scions on these rootstocks displayed a distinct dwarf habit compared to their standard size (self-graft and non-graft), and were also characterized by decreased stem thickness and internode length’. So, what you found just report those findings.
The dwarfing in grafted plants associated with decreased rootstock stem thickness, lesser branches, smaller leaves, and so on were presumably due to incompatibility between scion and rootstock (as appeared by inverted bottleneck: thinner rootstock stem and thicker scion stem) and can not be a positive dwarfing ness. If agree to this, may please revise the MS. Otherwise, provide suitable justification to prove your hypothesis.
Line 220-222: The impact of grafting as graft union on self-grafted plant was not evident, while it was found in grafted plants on lakoocha. Whether this was a similar phenomenon reported in those earlier studies cited. In my view, it is only an incompatible reaction between scion and rootstock that caused an inverted bottleneck (thinner rootstock stem than scion stem). Commercial ber (Ziziphus mauritiana) grafted on dwarfing jharber (Z. nummularia) has the same effect, hence not commercially acceptable. Whereas, see Gora et al., 2021 in which Fremont’ mandarin on ‘Pectinifera’ rootstock positively caused dwarfing rather than an incompatibility reaction (https://doi.org/10.1016/j.sajb.2021.08.037). I am concerned about its commercial success, otherwise, you simply report what was observed as suggested to change the hypothesis and objectives, accordingly the conclusion of the study.
Line 230-232: ….’Prediction of dwarfing phenomenon over time’: just prediction, far from reality!!!
References:
Need to be formatted as per the journal standard. e.g.,
Lochard, R.G.; Schneider, G.W. Stock and scion growth relationships and the dwarfing mechanism in apple. Hortic. Rev. 1981, 3, 315–375.
In addition to the above,
· Since it is a rootstock-related study, for better comprehension of the findings the compatibility index measurements were required which include grafting survivability percentage, the diameter of scion and rootstocks, stionic difference, and stionic ratio (SR ratio),
· Grafting survivability should have been assessed rather than graft compatibility per se as graft compatibility is an outcome of long-term effect [field (in)compatibility] that cannot be measured in one or two years.
· The record of photosynthetic parameters could have helped better explain the results of determining carbohydrate components.
Author Response
Please see attachment
Author Response File: Author Response.docx
Round 2
Reviewer 3 Report
I appreciate the authors for their commendable efforts made in the revision. They have appropriately revised the MS. and provided sound justification for the points highlighted. I agree with those justifications supportd by the additional data in the support.
However, I would suggest the authors must include the statement in the conclusion
'However, evaluation for graft compatibility of breadfruit/lokoocha combination is required in actual field conditions over a long period of time for its efficiency to produce satisfactory yields at a commercial scale.
Author Response
Reply: We have provided a statement: ‘However, evaluation for graft compatibility of breadfruit/lokoocha combination is required in actual field conditions over a long period of time for its efficiency to produce satisfactory yields at a commercial scale.’ to the Conclusion section as requested by the reviewer. The related correction is highlighted in yellow in the text.
