Effect of Iron Application on Rice Plants in Improving Grain Nutritional Quality in Northeastern of Thailand
Round 1
Reviewer 1 Report
This study determined the effect of Fe application with different methods on productivity and grain Fe concentration among 3 rice cultivars. This research is significant concerning the benefit to farmers and consumers. I have read it carefully and I am interested to observe that applying Fe fertilizer can be the way to improve grain Fe and productivity in rice, though it is variety dependent.
However, the written is quite clear and well understand to me, but the interpretation is poor and needs to be completely improved before being published in the journal.
1. The result and conclusion in line 16-22 are not very well interpret the interaction effect between rice cultivar and applying Fe to yield and grain Fe concentration. The term "concentration" should be used instead of "content" in this article.
2. Lie 55-62 the sentence is not very clear and not relevant. I think it should not be stated at this place.
3. The initial grain Fe concentration should be included in materials and methods as the authors mentioned different classifications of grain Fe concentration among the 3 rice cultivars.
4. The brackets are errors everywhere but not sure if it is because of the system or the initial manuscript.
5. The total amount of Fe supplied should be mentionded in each method to compare how much Fe was applied in total.
6. In Fe concentration measurement, the sample reference material should be added to here to ensure that all the batches were analyzed correctly.
7. The interpretation of the result is the problem here. The concentration of Fe in rice grain can be effect by dilution. The authors are encouraged to present the result of grain Fe content or relative grain Fe content from the whole plant. The higher Fe could result by decreasing in yield and/or plant type. Therefore it is better to present grain Fe content in comparing cultivars and Fe applications.
8. The repeat result is usually not good to present as found in table 6,7 and figure 3.
9. Combining figures would help the audience to have a better understanding in Fig. 4, 5, and 6.
10. The inclusion should be improved according to the result of the relative grain Fe content to the whole plant.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The manuscript “Effect of Iron Application on Rice Plant in Improving Grain 2 Nutritional Quality in North eastern of Thailand” aimed at evaluating the effects of different methods iron application on grain Fe concentration, growth and yield of three rice cultivars grown under supplemental irrigation in dry season of North eastern Thailand. Experiments (split-plot) were conducted in the dry seasons of 2017 and 2018 on same fields. The mode of Fe application was allocated to the main plots while the cultivars were in the sub-plots. Combining soil and foliar application produced rice with the highest Fe concentration in all cultivars. The subject area is interesting and is of importance globally. There are, however, several issues that have to be addressed before it can be considered for publication. The language is a big issue making review almost impossible. Authors should be made to do a language editing prior to submission. There are too many issues such that suggesting corrections will amount to re-writing almost the entire manuscript. I have pointed out a few obvious issues that should be addressed together with proper language editing to enable a meaningful review of the manuscript.
Introduction
This section was poorly done. The introduction should be improved to include a review of related studies to identify gaps in the earlier study that this manuscript seeks to address. Also check grammar throughout the text. What is/are the hypothesis for the study? Provide it
Materials and methods
Lines 88 to 94; Experimental design is a split plot with the method of Fe application while the cultivars were allocated to the split plot. Any reason for this? I though the mode of application is the main aim for this study rather than the cultivar. Hence, wondering why the cultivar is rather allocated to the sub-plot? This has implications for the interpretation of your results.
Move Table 1 from this section to the Results section.
Line 101; replace "applying" with ""application"
Line 129-131; The study was conducted for two years (2017 and 2018) on the same field. So you will have residual effects of treatments from year 2017 into 2018. A simple ANOVA cannot handle this. A mixed model analysis will be more appropriate.
Results
Re-order the presentation of the results section as follows;
3.1 Soil Characterization
3.2 Growth
3.3 Yield and yield components
3.4 Iron concentration in rice
3.5 Relationship between iron content in grain and grain yield
Combine fig 1 and fig 2 as a 2-1 graph, similar to what you have in Table 4 and Table 5. Not useful separating them. Also make the vertical axis line visible.
Combine Tables 6 and 7 into one Table.
Discussions
Line 320-321; so what does this mean? Discuss it! It's not enough to just repeat the results in the discussion section. What are the implications of your results?
Line 323-324; how do you explain this result?
Line 331-332; Rephrase the sentence!
Conclusion
The conclusion is basically a summary of the results. The authors should do a better job in this section.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Dear Authors,
Thank you for submitting the revised manuscript. Most of the points have been corrected. However, I have some concerns regarding the data presented in Figures 2&3. The relationship between grain yield and content is not usually present in this way. The grain Fe content was calculated by multiplication between grain yield and grain Fe concentration. The weight of yield is very high compared with Fe concentration. It is the reason why a high correlation is detected. The grain Fe content can be interpreted in grain Fe yield. The correlation between grain yield and Fe concentration should be done to detect the effect of grain Fe on yield and it is related to dilution effects. The total uptake or the ratio of Fe translocate from the shoot into grain can also be added. So, I suggested revising this part before being accepted as it is a very important issue for interpretation.
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
Line 129-131; The study was conducted for two years (2017 and 2018) on the same field. So you will have residual effects of treatments from year 2017 into 2018. A simple ANOVA cannot handle this. A mixed model analysis will be more appropriate.
I am not convinced by the.
The language in this text is a major problem. I have attempted to point out a few.
1. Line 9: “a” should be inserted between “is global”
2. Line 27: “to meet as” should be replaced with “required to meet”
3. Line 29: “to” should be inserted between “leading severe”
4. Line 33: “plant” should be replaced with “plants”
5. Line 34: “but low us and less mobility” should be replaced with “but with low use and low mobility characteristics”
6. Line 35: “Among all micronutrients, plants need iron more than other” should be replaced with “Plants need iron more than the other micronutrients”
7. Line 47 to 49: “However, the efficiency of iron application in the soil is limited when applied to the bad soils and poor Fe mobility, Iron can converses to unavailable forms, therefore soil Fe fertilization appears to be less effective and show iron deficiency in plant” should be rephrased for clarity.
8. Line 52: “micronutrients, including Fe increasing concentration” should be replaced with “micronutrients including Fe increases their concentration”
9. Line 54: “Because of most of studies focus” should be deleted and replaced with “Because studies focus more”
10. Line 54-57: “Because of most of studies focus on increasing grain yield and less so on increasing grain quality [19]. Nowadays, rice grain quality characteristics play an imperative role in dictating its market value, also have strong influence on consumer attraction, more consumers prefer high-quality produce [20,21].” Should be rephrased for fluency and clarity.
11. Line 78: “consists” should be replaced with “consisted”
12. Line 79: “methods included” should be replaced with “methods;”
13. Line 81: “which” should be inserted between “cultivars comprised”
14. Line 83: “plot.” should be replaced with “plots.”
15. Line 92: “by divided into 2 applications” should be replaced with “in two splits”
16. Line 104: “taken” should be replaced with “done”
17. Line 110: “of plant” should be inserted between “base to”
18. Line 111: “determine” should be replaced with “determined”
19. Line 114-115: “The grain yield was measured from 6 square meters of each plot, then determine grain yield per hectare at 14% moisture” should be rephrased.
20. Line 117: “the” should be inserted between “from grain”
21. Line 122: “to” should be inserted between “compared the”
22. Line 126-128: “At ninety days after transplanting, shoot was sampled from the shoot dry weight measurement, then analysis the Fe concentration. The iron uptake in shoot was computed 127 by concentration (mg/kg) x shoot dry weight (kg/ha).” Should be rephrased for clarity.
23. Line 143-144: “This was probably due to iron accumulation in soil by application iron fertilizer in the previous year”. Should be rephrased.
24. Line 148: “combined analysis of two years” should be rephrased for clarity
25. Line 154: “combine analysis of two year” should be rephrased.
26. Line 159: “hight” should be spelled “height”
27. Line 160: “season” should be replaced with “cropping”
28. Line 189: “There was a significant (p ≤ 0.05) interaction of iron application methods with cultivars for brown rice grain iron content in combined analysis of two years” should be rephrased for clarity.
29. Line 191: “shown” should be replaced with “showed”
30. Line 201: “the” should be deleted
31. Line 202: “combined analysis of two years” should be rephrased or replaced with “the analysis of the combined two cropping seasons”
32. Line 202-205: “The highest shoot iron uptake was found in the soil combined with foliar application treatment for Chainat1, Riceberry and 203 Tubtim Chumpae cultivars. While, all iron fertilizer application methods give significantly higher shoot iron uptake for Chainat1 and Riceberry cultivars” should be rephrased for fluency.
33. Line 207: “combined analysis of two years” should be rephrased for clarity.
34. Line 220: “interation” should be replaced with “interaction”
35. Line 226: “The brown rice grain iron concentration was low positively correlated with grain yield both cropping years” should be rephrased for clarity.
36. Line 227: “is” should be replaced with “was”
37. Line 228: “associate” should be replaced with “associated”
38. Line 228: “the” should be inserted between “of three”
39. Line 230-233: “According to rice cultivar, Chainat1 (poor iron concentration) had greater correlation value of brown rice grain iron content and yield than the Riceberry and Tubtim Chumpae (rich iron concentration) both cropping years” Should be rephrased for clarity.
40. Line 260: “Relationship of brown rice grain iron concentration with grain yield in separate of each year and cultivar” should be rephrased for clarity.
41. Line 271: “those” should be inserted between “over without”
42. Line 276: “Foliar applied iron cause greater increases iron content in brown rice grain than soil application” should be rephrased for clarity.
43. Line 281-283: “The mobilization and retranslation of the deposited micronutrient reserves from the vegetative tissues to grain and the key affecting grain accumulation micronutrients which differ in their genetic capacity of rice cultivars” the sentence appears incomplete and should be revised for clarity.
44. Line 289: “indicates” should be replaced with “indicated”
45. Line 290: “respond” should be replaced with “response”
46. Line 301: “Iron plays a significant role in various physiological and biochemical pathways in plants as well as photosynthesis, involved increasing of grain yield” this sentence should be rephrased for clarity.
47. Line 308: “give” should be replaced with “gave”
48. Line 309: “Varietal differed in tolerating to iron deficiencies were reported by several types of research” should be rephrased for clarity
49. Line 310: “Iron deficiency caused entire leaves to become chlorotic and resulting to reduce the photosynthesis [40]. In contrast, foliar iron fertilizer application was not significantly different in grain yield among rice cultivars as reported by Fang et al. (2008) [12].” should be rephrased for clarity.
50. Line 319: “those” should be inserted between “over without”
51. Line 322: “in” should be inserted between “increase the”
52. Line 320-326: This has to be rephrased for clarity
“This was probably due to all iron fertilizer application methods increase iron concentration in shoot and shoot dry weight (Data not shown) and resulting to increases the iron uptake by plant. This led to an increase the translocation of iron into the grain. However, accumulation iron concentration in grain was not only achieved through remobilization of previously stored shoot minerals but also continued uptake and translocation of minerals during grain filling [42,43]. This finding is in agreement with Yadav et al. (2013) [44].”
53. Line 327: “cultivar” should be replaced with “cultivars”
54. Line 328: “give” should be replaced with “gave”
55. Line 328: “for all applying iron fertilizer methods, following” should be replaced with “for all iron fertilizer application methods, followed”
56. Line 330: “in” should be replaced with “under those”
57. Line 339-340: “The increase of iron content varied among different rice cultivars, depended on their responsiveness to the iron fertilizer application and initial soil iron content.” This should be rephrased for clarity.
Line 344: “cultivar” should be replaced with
Author Response
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Author Response File: Author Response.pdf
Round 3
Reviewer 1 Report
Dear Authors
Thank you for the revision of the manuscript. The interpretation is much better but I still have some major concerns regarding the result in Table 3&4.
In Table 3, the no of tillers per hill is very low to me. Could you check your data again? This consequently influences the data in table 4. The panicle no per hill is also very low. Please check your data. If the number is correct, I think there was a problem with your crop. Grain yield of the 3 selected rice varieties was extremely low at 1,000-1,200 kg/ha, while the varieties are high-yielding rice varieties in Thailand. What I am concerning is if crops are not completely grown, the responses to fertilizer applied may not be the actual responses. I regret to express that I can not accept the current data presented in the manuscript.
Author Response
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Author Response File: Author Response.pdf
