Characterization of Soluble Sugar Content, Related Enzyme Activity and Gene Expression in the Fruits of ‘Minihyang’ Mandarin on Different Rootstocks
, Eun Ui Oh 1, Seung Gab Han 2, Su Hyun Yun 2, Ho Bang Kim 3 and Kwan Jeong Song 1,4,*Round 1
Reviewer 1 Report
In this manuscript the authors compare the performance of Minihyang mandarin onto two different rootstocks, Poncirus trifoliata and Flying Dragon. For that end, they measured tree growth (production, fruit quality, thorns, etc), sucrose metabolic enzyme activities and the expression of six genes related with the regulation of sugar metabolic enzymes. In general terms, this works has limited interest for the global citrus research community although it can be of great interest for Korean growers and especially for the Jeju island. The work has been well conducted, indicating clearly what they want to do and with proper methodology. In this regards, this work could be improved analyzing this variety onto these rootstocks during different seasons to reinforce the results. However the most important and clear differences have been observed on scion tree vegetative growth, yield, and fruit quality parameters rather than enzyme activity and gene expression. These very large differences observed in the tree and in the fruits can be clearly assumed to be due to the rootstock even though they have been evaluated in a single year. Do you know if these differences have maintained in other locations?.
I suggest to the authors to improve the introduction of the manuscript. I am missing a broader explanation of what is the varietal structure of mandarins in Korea or in Jeju island and what advantages or why this new variety stands out. I miss also some pictures about the fruit and variety grafted onto both rootstocks. Summarizing, in my opinion this manuscript can be published in Horticulture MDPI journal taking into consideration comments described before and some minor comments indicated in the next paragraphs.
Lines 15-17. These lines are difficult to read, please try to rewrite them for better understanding.
Line 44. Poncirus trifoliata (L.) Raf. Add (L.).
- Write properly Phytophthora
- What are the parents of Minihyang hybrid?. If you do not want to write it at least indicates the botanical name of male and female parents.
- Change testified for evaluated.
57 to 68. This paragraph is loose and not tied up, I suggest to improve it.
- Citrus reticulata Blanco.
90-92. These lines are difficult to read, please try to rewrite them for better understanding.
- One square bracket is missing.
164-166. Rephrase these lines.
Table 1 and 2. Z Mean separation …. Superscript Z is not indicated on the table and explain what means the asterisk.
Figure 1d. What means the parameter b?. Indicate some reference describing the calculation method.
- Some names of varieties are written with “ “ instead ` ´. Check the text. (line 272, 318).
I am not a native English speaker but I think that English editing must be improved a lot.
Author Response
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Reviewer 2 Report
In fruit crops, choosing a suitable rootstock is very important to the industry. In this study, the author first evaluated the effects of two rootstocks on tree vigor, yield and fruit quality (mainly included sugar and acid content), and then analyzed the differences in enzyme activities related to sugar content metabolism. Finally, the effects of different rootstocks on gene expression for sugar metabolism were analyzed. The full manuscript is written smoothly and the level is clear. I only have one question. On pages 304-312, the author discusses the reasons for choosing these genes, but the genes that play a key role in different varieties are different. Why don't authors choose transcriptome sequencing to do this stuyd. Selecting genes only based on previous study is unreliable.
Author Response
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Author Response File: 
Author Response.docx
