Inflorescence Traits and Floral Quality Parameters in Promising Olive Clones (cv Leccino): Influence of the Canopy Position

Round 1

Reviewer 1 Report

The manuscript presents an interesting aspect of evaluating selected clones, which may lead to new forms that are valuable for olive cultivation. The authors have skillfully interpreted the traits that determine the suitability of cultivated forms as potential pollinators. The authors also confirmed the significant effect of available light on yield-forming traits in olive. The study was designed properly and carried out on a considerable number of objects. Minor editing errors (attached below) do not reduce the substantive significance of the results. 

1. At what stage was pollen collected for viability determinations (before anthesis, after antehsis) and from how many flowers for each zone? Were they determined for a mixture of flowers or for individual flowers?
2. I would standardize the spelling : Leccino (l. 12, 77, title of Table 1, l. 248, 268, 286, title of figs. 4 and 5,, l. 364, 377) or 'Leccino' (title, l. 89). Even when the authors refer to clones, these are clones within a cultivar.
3. I am not an expert of English language, but it seems to me that : l. 65 "of" is unnecessary, l. 67 double "evolution" seems to be too much.

Author Response

Dear Reviewer,

thank you for your comments and suggestions which have been very appreciated. Thus, the manuscript has been revised according to your observations. The improvements are shown in the tracked manuscript.

Below, the point by point replies.

1: At what stage was pollen collected for viability determinations (before anthesis, after antehsis) and from how many flowers for each zone? Were they determined for a mixture of flowers or for individual flowers?

R: In the text, more detailed information has been added at line 169-171.  A mixture of flowers was used. The information has been added at line 170-71.

2: I would standardize the spelling: Leccino (l. 12, 77, title of Table 1, l. 248, 268, 286, title of figs. 4 and 5,, l. 364, 377) or 'Leccino' (title, l. 89). Even when the authors refer to clones, these are clones within a cultivar.

R: As suggested, the text has been modified and the quotation marks have been removed.

3: I am not an expert of English language, but it seems to me that: l. 65 "of" is unnecessary, l. 67 double "evolution" seems to be too much.

R: The errors have been erased.

Reviewer 2 Report

The MS (No.Horticulturae- 1675235) evaluated differences in inflorescence traits and floral quality parameters of three olive clones among external zone and internal zone in which indicating the different light conditions. Olive species are very important economical plants widely planted in the world. The authors have conducted intensive experiments trying to compare the difference of inflorescence/flower trait, ovary structure, viability and germination of pollen grains between three clones of Olea europaea, and two position within inflorescence. 

In general, I find the ms have clear experimental designs, understandable results. However, I also think there could be flaws in the aim of study and in the interpretation of the results which should be considered or at least clarified. In addition, it is not clear how the data analysis performed and paragraph structure subdivided. Thus, the manuscript need to be revised before publication. Below I provide some general comments and not an exhaustive list of minor comments.

General comments:

1. Although the authors pointed out the main objective of this study was to evaluate differences in inflorescence traits and floral quality parameters of three olive clones (L74-76), I am still confused about what is the subject and the purpose of your article after studying the abstract and introduction. Is it trying to find out which cloneis best? If so, this subject should be highlighted .
2. I think the first paragraph in Introduction is too long and readers are hard to follow your highlights. I would suggest streamlining the the paragraph.
3. Please provide detailed information on “BBCH-identification”when it appeared in MS for the first time. 
4. The methods on data analysis were not fully described, I think the section of data analysis needs a major revision, the current version was far from publication. First, the effects of year on inflorescence/flower trait, ovary structure, viability and germination of pollen grains did not be considered in the ms throughout. Second, the author performed data transformed to satisfy normality and homoscedasticity assumptions, including log, square-root and square, but failed to point out the detailed methods for each data set. In addition, not all data transformation methods could receive normally distributed data successfully.
5. In the result of environmental conditions and phenological evolution, the author thought that the air temperature was significant difference between the two years during the experimental period, but the no significant difference need to be analysed with the data sets. The same problem arises in result of rainfall.
6. Were the average of air temperature and rainfall significantly different between experimental duration in 2017 and 2018? I suggest to clarify it in Fig. 1.
7. I think the Fig. 2 of ms was not clear on the schedule of flower development, please reference Fig. 4 from the paper of Paudel et al., 2018. In addition, why the three different clones not separated?  
8. For the Table 1, the author only provided the statistics results of Two-way Anova, the results of multiple comparisons between clone or canopy position were missing. In addition, the results presentation of Two-way Anova were inappropriate, for instance, the “03500*”indicated the same meaning in deed (p < 0.05), the number should be replaced by F-value. Furthermore, the value of df also should be provided. The same problem arises in Table 2.
9. The results of multiple comparisons difference of statistics should be showed in the Fig. 4 and Fig. 5. Moreover, I think the fertiled ovaryshould be counted and compare with each other.

Other minor comments

1. There were no results to support the author’s ideas (L346-347)
2. The “clone× canopy position” could not support the idea of text description “For clones L 1.3 and L 1.4 the decrease of open flowers ranged between 30.5 and 67.8% with the greatest reduction measured in year 2018” (L346-347).
3. There are many mistakes in the literature, such as the journal name in line 398-399, please double check all the list of references carefully.
4. Rainfall (mm) should be replaced by average rainfall (mm) in Fig .1.
5. Please clarify the type of ovaries on y-axis in Fig. 4.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

thank you for your comments and suggestions which have been very appreciated. Thus, the manuscript has been revised according to your observations. The improvements are shown in the tracked manuscript.

Below, the point by point replies.

R: Although the authors pointed out the main objective of this study was to evaluate differences in inflorescence traits and floral quality parameters of three olive clones (L74-76), I am still confused about what is the subject and the purpose of your article after studying the abstract and introduction. Is it trying to find out which clone is best? If so, this subject should be highlighted.

A: We have modified the last sentence of the introduction section (line 82-85) to better highlight the subject of this study.

R: I think the first paragraph in Introduction is too long and readers are hard to follow your highlights. I would suggest streamlining the paragraph.

A: The introduction paragraph has been shortened.

R: Please provide detailed information on “BBCH-identification” when it appeared in MS for the first time.

A: More information has been added (line 128-130).

R: The methods on data analysis were not fully described, I think the section of data analysis needs a major revision, the current version was far from publication. First, the effects of year on inflorescence/flower trait, ovary structure, viability and germination of pollen grains did not be considered in the ms throughout. Second, the author performed data transformed to satisfy normality and homoscedasticity assumptions, including log, square-root and square, but failed to point out the detailed methods for each data set. In addition, not all data transformation methods could receive normally distributed data successfully.

A: The data analysis section has been modified giving more detailed descriptions (L. 188-198). Moreover, in the result section, a supplemental table reporting the year effect on inflorescence traits and floral quality parameters has been added. The section has been modified and the data transformation procedure has been specified.

R: In the result of environmental conditions and phenological evolution, the author thought that the air temperature was significant difference between the two years during the experimental period, but the no significant difference need to be analysed with the data sets. The same problem arises in result of rainfall. Were the average of air temperature and rainfall significantly different between experimental duration in 2017 and 2018? I suggest to clarify it in Fig. 1.

A: Metereological data are generally not subjected to statistical analysis, thus, even if differences in air temperature between years are evident (about 3-4 ° C) we did not use the term “significant” in the text. A similar approach was used for the rainfall data.

R: I think the Fig. 2 of ms was not clear on the schedule of flower development, please reference Fig. 4 from the paper of Paudel et al., 2018. In addition, why the three different clones not separated?

A: We think that this figure is adequate. This is a typical approach to show the evolution of phenological stages, in agreement with the literature on floral biology. In particular, the paper by Oteros et al. 2013 (Agriculture, Ecosystems & Environment, 179, 62-68) has inspired Figure 2. Moreover, in the figure, clones were not separated because, as specified at line 229-230, the evolution of phenological stages was similar among clones.

We are sorry but, about the suggested reference, our search returned uncertain results. In the manuscript by Paudel et al., 2018 (‘Elevated CO2 compensates for drought effects in lemon saplings via stomatal down regulation, increased soil moisture, and increased wood carbon storage’. Environmental and Experimental Botany) we did not find a suitable Fig. 4.

R: For the Table 1, the author only provided the statistics results of Two-way Anova, the results of multiple comparisons between clone or canopy position were missing.

A: The Table 1 has been improved, as suggested. Within each measured parameter, the significance from multiple comparison test is now indicated.

R: In addition, the results presentation of Two-way Anova were inappropriate, for instance, the “03500*”indicated the same meaning in deed (p < 0.05), the number should be replaced by F-value. Furthermore, the value of df also should be provided.

A: We have modified the presentation including F-values. The p values were maintained in order to highlight the level of significance for each factor and for their interaction.

R: The same problem arises in Table 2.

A: The Table 2 has been modified, similarly to Table 1.

R: The results of multiple comparisons difference of statistics should be showed in the Fig. 4 and Fig. 5. Moreover, I think the fertiled ovary should be counted and compare with each other.

A: In Fig. 5, differences from the multiple comparison test have been indicated within each year. Concerning the Fig. 4, we believe that suggested changes could make it less clear for the reader and, thus, we prefer to maintain it in its current form.

About the comment ‘fertiled ovary’, we did not fully understand. If you are referring to the fertilization process, it was not a focus of this study. Indeed, ovaries were sampled from flowers at initial opening of petals, before pollination. To better clarify this point, the sentence at line 150-151 has been integrated.

R: There were no results to support the author’s ideas (L346-347)

A: We have modified Fig. 5 indicating significant differences between canopy zones and clones within each year.

R: The “clone× canopy position” could not support the idea of text description “For clones L 1.3 and L 1.4 the decrease of open flowers ranged between 30.5 and 67.8% with the greatest reduction measured in year 2018” (L346-347). L242

A: We agree, this sentence has been removed.

R: There are many mistakes in the literature, such as the journal name in line 398-399, please double check all the list of references carefully.

A: The literature has been carefully revised.

R: Rainfall (mm) should be replaced by average rainfall (mm) in Fig .1.

A: The histograms in Fig. 1 represent the daily rainfall not an average.

R: Please clarify the type of ovaries on y-axis in Fig. 4.

A: Considering the integration at line 150-151, we think to maintain the y title.

Round 2

Reviewer 2 Report

The MS (No.Horticulturae- 1675235) evaluated differences in inflorescence traits and floral quality parameters of three olive clones among external zone and internal zone in which indicating the different light conditions. The authors have done a thorough revision following the last review, and my comments are minor primarily. However, I have suggested a few edits that I feel better to represent this study's findings and primarily request to revise the data analysis and results. Below, I have some suggestions to improve the clarity of the ms. I hope it helps in some way.

1. Although the authors have revised the data analysis and given more detailed descriptions in the revision ms, I also think this is not enough to explore the difference in The author repeatedly highlighted the important roles of rainfall and air temperature on inflorescence traits and floral quality parameters. Still, there is a lack of compelling data to support it, such as whether the air temperature showed a significant difference between the periods of the experimental trials. The meteorological data should be subjected to statistical analysis, and it's feasible when the author controlled the rainfall or air temperature data of each experimental trials period as a dataset. Thus, I suggest that the meteorological data should be analyzed. This could explain the difference between inflorescence traits and floral quality parameters better.
2. Please check the sign of significant results in table 1, especially on the flowers per inflorescence in 2018.
   
   3. Please confirm the sign of "N°"?
   
   4. I think Fig. 4 did not show the difference indeveloped ovule number among clones or canopy positions. Moreover, I suggest that the author could provide the number of developed ovules (≥ 3-4/4) per clone or per canopy position only; this is sufficient to achieve the author's purpose because the flower produces fixed four ovules. In addition, this can match with statistical results in table 2.
3. Why did the dataset of the percentage of pollen germination in table 2 not comparedbetween canopy position?

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

thank you for your revision. According to your comments the manuscript has been modified. Changes are shown in the tracked manuscript.

Below, the point by point replies.

1. The statistical analysis on the meteorological data has been performed and a table has been added as supplemental material (Table S1). See at lines 191-193; 205, 209, 212.
2. Values in Table 1 have been checked and, concerning the flowers per inflorescence 2018, we noticed a transcription error which has been corrected. The right p value was 0.0189 instead of 0.0419.
3. In Table 1, the number symbol has been correctly modified as No.
4. Thank you for your suggestion. Figure 4 and Table 2 are complementary and we believe it is important to show the differences in 0/4, 1/4 and 2/4 ovules as well. For these reasons, we prefer to keep Figure 4 in its current form.
5. Differences in pollen germination were never significant and thus data are not reported in Table 2. We have added a sentence in the legend to explain why they are missing.