Response of Seedling Growth Characteristics to Seed Size and Cotyledon Damage in Quercus wutaishanica
Round 1
Reviewer 1 Report
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Comments for author File: 
Comments.pdf
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Author Response
General comment:
- This is a simple, but a generally well executed study to examine the effect of cotyledon excision and seed size on seedling morphology in a controlled setting. However, the authors need to add additional information in the methods, particularly related to the statistical design and analysis before publication.
Response: Accept.
Thank you for your valuable suggestions, we have re-analysed all the data statistically (lines 141-145).
- There is a need for better description in the methods for how leaf area was calculated. The authors state that water was absorbed using paper towels, but this is obviously not a method to calculate leaf area! Please describe how leaf area was measured. Also, what precision was used to measure the different variables (example: was height measured to nearest mm or cm, etc.).
Response: Accept.
Thank you for your valuable advice. We have revised methods. Because the plants were obtained from the soil with soil, we rinsed the soil off the surface of the plants with water and then dried the surface of the leaves with absorbent paper to facilitate the determination of the leaf area of the plants with a leaf area meter. The unit for the height of the plant was indeed written wrongly by us and we revised the unit for the height of the plant (lines 128-130).
- The experimental design is not stated in the methods. It is not clear if the treatments were completely randomized (seed size and excision treatments randomly placed within each of the 12 plots). It appears the plots are blocks and each treatment combination was placed into one of the 12 plots. There were 3 replications of each treatment. Therefore, I’m guessing that they used a completely randomized treatment design with a factorial treatment arrangement (size X excision).
Response: Accept.
We are very sorry for the confusion caused by the experimental design not being explained. We used a completely randomised design in which large and small seeds were equally divided into 12 portions each and randomly sown in 24 plots with 50 seeds per plot. The size of seeds sown in each plot was marked with plastic. After the seeds grew the first true leaves, four plots were randomly selected in the plots sown with large seeds, namely, no cotyledons were excised (as control), 1/4 of the cotyledons were excised (defined as mild injury), 1/2 of the cotyledons were excised (defined as moderate injury), and all of the cotyledons were excised (defined as severe injury), and there were a total of three replications for each treatment, and the cotyledon treatment for small seeds was the same as that of the cotyledon treatment for large seeds (lines 106-110, 116-120).
- The results show significant differences with relatively low small differences between treatments in the figures. For example, in Figure 1, the difference between the control and heavy excision is so small as to be undetectable on the graph, but the graph shows the two treatments were significantly different. I suspect the authors were not using the correct error term in their models and may have committed a Type 1 error (falsely rejecting the null hypothesis). The error term should have a degree of freedom of 2 for the main effects and 2 for the interactions. I suspect they were using the subplot data incorrectly as the degree of freedom (50 acorns -1=49). This needs to be clarified before publication!
Response: Accept.
We used a general linear mixed effects model to statistically analyse the data spoiling, with seed size and cotyledon excision as fixed factors and Plot as a random factor, to analyse the effects of seed size and cotyledon excision on the growth characteristics of Quercus wutaishanica. Then, we used multiple comparisons to analyse the effect of cotyledon excision on the growth characteristics of Q. wutaishanica seedlings, and used paired t-tests to analyse the differences in the growth characteristics of seedlings with small-sized seeds in the same treatment (lines 141-150).
- Please provide clarity on selection of acorns (lines 87-96). Methods state that 500 acorns were harvested from 30 trees, but only 1200 acorns were used in the study. It is not clear if the acorns were kept separate by collection tree or if they were bulked together. If they were bulked, were the acorns mixed properly so that each acorn from each collection tree had a random chance of being selected in the final selection, or were some mother trees more represented than others? Also, what was the criteria for selecting Large and Small acorns. Were these visually assessed by first splitting the acorn lots into two groups evenly (Large vs small)?
Response: Accept.
We selected 30 robust Q. wutaishanica shrubs and picked a total of about 500 seeds from four different directions on each tree. The extracted seeds were mixed thoroughly and 600 seeds of each size without pest infestation were selected from them by observation, and 100 seeds of each size were randomly selected by measuring the length, width and fresh weight, and significant differences in the length, width and fresh weight of the seeds of each size were reached (lines 92-95).
- Methods on treatments: Section 2.2 needs some revising. The treatments need to be defined before the equation (line 104-105). Otherwise, the reader is left wondering ‘what treatments?’. Line 111 implies all the acorns were excised, when only a portion of them were. Also, did you ensure that seed size measurements were relatively equal among the three replications of each treatment? Even within the large and small classes, you will have variation.
Response: Accept.
Thank you very much for the heads up, we have modified Section 2.2 to ensure that the reader is not confused, and that our size seeds are sown completely randomly in each plot, so that we can artificially duplicate the problem of inter-seed sizes being relatively equal (lines 106-110).
- There were a few grammatical errors, and I suggest some different terminology. For example, the authors should use an alternative to the use of ‘higher’ and ‘lower’ in the results and discussion. They also miss the definite article, ‘the’ in some instances, but I did not correct this in every case. The use of phrases like one the one hand’ is too conversational for a refereed journal article. The authors should have an English language review of the paper before submission.
Response: Accept.
Thank you for your kind reminder and pertinent advice, we have checked the article for grammatical issues and replaced some words to avoid colloquialisms in the article.
Specific comments:
Line 23 – What is meant by ‘the large and small seed germination’? Do you mean large and small seed groups?
- The conclusions section is quite weak. These are not actually conclusions, but a repetition of the results and discussion. The authors should describe how their results could affect or influence the current understanding of seed/seedling biology, silviculture, nursery production, or forest management.
Response: Accept.
Thank you for your suggestion. Based on your suggestion, we have rewritten the conclusion section to highlight the practical value of this experiment for forest seedling cultivation and management (lines 300-312).
Specific comments:
- Line23 – What is meant by ‘the large and small seed germination’? Response: It means the germination of seeds of different sizes and we revised this sentence (line 23).
- Line 35 – change ‘mainly’ to ‘main’
Response: Accept. Thank you for your suggestion, we have revised ‘mainly’ to ‘main’ (line 35).
- Line 52-53 – This sentence is not grammatically correct, please rewrite. Also, why are citations listed here. They are supposed to be listed by number, correct?
Response: Accept. We've changed the grammar of this sentence, as well as the citation format of the reference (lines 52-53).
- Line 81 – Delete ‘hazards’
Response: Accept. We have deleted 'hazards' (line 81).
- Line 80-83 – I would suggest splitting this sentence into two sentences. What is meant by ‘provide a reference’? Please be more specific here. I think you might be saying this work will help to refine breeding and restoration efforts?
Response: Accept. We fully accept your suggestion and we have changed the sentence to two sentences and modified the sentence to make it easier for the reader to understand (lines 79-82).
- Need a space between the genus and species.
Response: Accept. Thanks for the reminder, we've added a space.
- Line 91 – It is not clear what the ‘seed harvesting stand area’ is. Is this a predetermined identified area or just the area where seeds were harvested? I would suggest deleting this phrase.
Response: Accept. We have deleted this phrase (lines 90-91).
- Line 92 – what is meant by orientation?
Response: Accept. We apologise for the confusion, we have replaced the word "orientation" with the word "directions" (line 93).
9.Line 103-104 – delete ‘selected and’ from the sentence because selection was described in the paragraph above. Replace ‘repeated’ with ‘replication’.
Response: Accept. Thanks for the suggestion, we have deleted ‘selected’, and replace ‘repeated’ to ‘replication’ (lines 107, 121).
- Line 117 – delete ‘for seedling establishment’. And place a comma before ‘and’
Response: Accept. Thanks for your suggestion, we have removed 'for seedling establishment', and added a comma before ‘and’ (line 124).
- Line 123 – It is not clear why absorbing water from the plant is necessary here? Is this part of the experiment somehow (measuring the water removed from the tree)?
Response: Accept. After the seedlings were harvested, the plants carried soil, so we rinsed the surface of the plants with water, and in order to facilitate the determination of the leaf area of the seedlings with a leaf area meter, we used blotting paper to suck up the water droplets left on the surface of the plants. We have rewritten this sentence for the convenience of our readers.
- Line 134: Please use past tense. Change ‘are’ to ‘were’.
Response: Accept. Thanks for the advice, we have revised the content (line 141).
- Line 144: It should be ‘SigmaPlot’, but I don’t think it is necessary to specify how graphs were made. I suggest deleting this information
Response: Accept. We take your advice and have removed the information here.
- Line 148: Please use past tense. Change ‘have’ to ‘had’
Response: Accept. Thanks for the heads up, we have revised it (line 154).
- I could not find where Table 1 was referenced in the text.
Response: Accept. Thanks for the reminder, we have revised this table (line 207).
- Line 152: Please change to ‘Table 2’.
Response: Accept. Thanks for the heads up, we have revised it (line 207).
- Line 154: replace the comma with a period to avoid a run-on sentence. Also, the second ‘seedlings’ should be ‘Seedling’.
Response: Accept. Thanks for the heads up, we have revised it (line 160).
- On Table 2, the P values that are listed as zeros should be changed to ‘<0.001’.
Response: Accept. Thanks for the heads up, we have revised it (line 208).
- On Figures 1 and 2, change the legend to read ‘Large seed’ and ‘Small seed’ by removing ‘seedlings from’. Also, on Figure 1, were the shoot height values in cm or mm? A 300 cm tree in this short of a timeframe with a correspondingly small diameter does not make sense.
Response: Accept. Thanks for the heads up, we have changed the Legend to read 'Large seed' and 'Small seed.' It's true that the units are in mm here, and we've reworked the units (lines 209-217).
- Line 221: The first sentence needs a period after the citation number.
Response: Accept. Thanks for the heads up, we have added a period after the citation number (line 221).
- Line 245: Are you suggesting that the size treatment did not affect the RSratio because the plots did not differ in soil nutrient availability? Please be more clear here
Response: Accept. Thanks for the suggestion, we have revised the sentence (lines 241-242).
- Line 257: What is meant by ‘transformed’? Do the authors mean ‘transferred’?
Response: Accept. We are very sorry for the confusion, we meant what you understood to mean 'transferred'. We have replaced 'transformed' with 'transferred' (line 273).
- Line 261: This sentence does not make sense to me. Please revise.
Response: Accept. Thanks for the suggestion, we have revised it (line 279).
- Lines 262-270: I found most of this repetitive of what was already described in the introduction. I suggest shortening this to only a sentence or two.
Response: Accept. Thank you for your suggestion, it has been modified according to your suggestion (line 283).
- Line 286-290: This is one long run-on sentence. Please split into 2 or more sentences.
Response: Accept. We have rewritten this section based on your suggestions.
Reviewer 2 Report
The manuscript entitled "Response of seedling growth characteristics to seed size and cotyledon damage in Quercus wutaishanica" is an interesting study on exploring the role of seed size and cotyledons damage on seedling growth and responses. The findings of the study have ecological significance and can be considered for publication. However, there are a few minor concerns which need to be addressed before proceeding further. Particularly, a thorough literature survey on role of seed size on seedling performance can be done. Why Chi-square test was performed? Statistical analysis and its presentation in the figures can be slightly updated. There are a few typological and word sticking issues which should be resolved. References need to be formatted as per the journal style. A few suggestions are annotated in the attached pdf file.
Comments for author File: Comments.pdf
The language is fine but a few sentences need to be rephrased for better clarity.
Author Response
- Line 23 rewrite the sentence for more clarity!
Response: Accept. Thanks for the suggestion, we have revised this section (line 23).
- replace the words already present in the title with other relevant keywords, Arrange the words alphabetically!
Response: Accept. We have replaced duplicate words and rearranged keywords in alphabetical order (line 31).
- rewrite it with better clarity!Provide information about the 4 treatments?
Response: Accept. Thank you for your suggestion, we have rewritten this section and provided information on the 4 treatments (lines 121-122).
- why chi-square test?
Response: Accept. We re-analysed the data using a general linear mixed effects model (lines 141-145).
- it would be better to replace capital letters with * for significant observations.
Response: Accept. Thank you for your suggestion, we have replace capital letters with * (line 215).
- check reference formatting and arrange accordingly!
Response: Accept. We have checked and modified the references used (lines 317-373).
