Potential of Purple Non-Sulfur Bacteria in Sustainably Enhancing the Agronomic and Physiological Performances of Rice
Round 1
Reviewer 1 Report
The manuscript titled “Potential of Purple Non-sulfur Bacteria in Sustainably Enhancing the Agronomic and Physiological Performances of Rice- a Review” reports an interesting work discussing the importance of using purple non-sulfur bacteria to enhance rice production under field conditions. The article also seeks to identify the research gaps from previous studies on rice using PNSB and suggest pathways for future research. This is a well-written article and I anticipate that the manuscript should be of great interest to the researchers working on the PNSB and their application under field conditions. I include my comments below, most of them are suggestions to improve the overall quality of the publication. I considered the manuscript suitable for publication subject to the following improvements.
Specific Comments
Overall, the study is well designed and presented in a good way. However, many sentences include repetitive words and are not explained and cited appropriately.
Line 25-27: restructure the statement, please
Line 115-117: elaborate the statement and mention fertilizers etc.
Line 142-144: Connect the two paras, and require a statement that links the paragraphs.
Kindly replace the word “Flooded” with “Waterlogged” or “Waterlogging” throughout the manuscript.
Add a para that reveals the effect of PNSB on the hormonal regulation of rice plants.
Add some details on Microbial Plant Biostimulants (MPBs) you may consult “https://doi.org/10.1080/17429145.2022.2091801”.
Literature cited and discussed in a proper way (well written and presented).
Incorporate some latest references.
The article should become acceptable after minor revisions of English / grammatical mistakes.
Author Response
Dear reviewer,
Thank you very much for your valuable comments and suggestions on our manuscript. We have made the changes to the manuscript based on your comments and suggestions. Here is a brief of what changes we have made.
Comments and Suggestions for Authors
Line 25-27: restructure the statement, please
The statement was restructured. Please see lines 25-28
Line 115-117: elaborate the statement and mention fertilizers etc.
Additional information was added. Please see lines 133-134
Line 142-144: Connect the two paras and require a statement that links the paragraphs.
The paragraphs were connected as suggested. Please see lines 166-169
Kindly replace the word “Flooded” with “Waterlogged” or “Waterlogging” throughout the manuscript.
This word was replaced throughout the manuscript with the suggested word
Add a para that reveals the effect of PNSB on the hormonal regulation of rice plants.
The paragraph was added. Please see lines 90-97
Add some details on Microbial Plant Biostimulants (MPBs) you may consult https://doi.org/10.1080/17429145.2022.2091801
The information was added. Please see lines 156-158
Literature cited and discussed in a proper way (well written and presented).
Incorporate some latest references.
The latest references were added as suggested
The article should become acceptable after minor revisions of English / grammatical mistakes.
Author Response File: 
Author Response.docx
Reviewer 2 Report
The review (Potential of purple non-sulfur bacteria in sustainably enhancing the agronomic and physiological performances of rice- a review) makes a global analysis and discuses different aspects on the beneficial use of PNSB in crops production, mainly in rice. The review offers a global and current vision about topic. The issue is the enormous interest not only for the scientist community but also for the society. Although physiological is in the title, I miss more physiological aspect in relation with the beneficial use of PBNS in crops growth and yield, and abiotic resilience. . In general, the manuscript is clearly written and well-structured and should be published following consideration and comments:
P1 L40.- Citation style must to be normalized. (Sunder and Chen, 2020), this reference is not included in the bibliography.
P1 L41-43. This sentence must to be review. It´s clear the negative effect of climate indicator on plant production. However, from many years ago, it has been described a positive effect of the increment of free air CO2 on photosynthesis and crop yield, mainly in C3 plants. Please review this interesting paper in rice about the topic.
https://doi.org/10.1016/j.scitotenv.2021.151017
P2 L46.- lower could be changed by slow down the rice development rate and the time….
P2 L53.- thousand-grain weight is a method to quantify the grain size when the grains are small. I suggest that grain size is more proper.
P257.- I would include comparative instead of superlative “a higher warming potential than…”
P2 L78-79.- Ref. 26 remarks to Rhodopseudomonas and Rhodobacter as main group of PNSB, why do you include to Rubrivivax in this category?
Figure 2.- The figure 2 is not mentioned in the text. It is not common that figure 3 come immediately after the figure 1, P2 L77-L93.
P3 L99.- In reference to different papers you use Rhodopseudomonas capsulatus and Rhodobacter capsulatus. Bot names are synonyms of the same type but it can be confused for the reader. I don’t know it is possible formally but I suggest that use only one.
P3 L106.- The sentence about Harada et al. experiments are very interesting but, after review the original paper, the set up explanation could be rewrite in a clearer manner.
P3 L106.- R. palustris is the first time that appear in the text and it must not be abbreviate because the reader unknown the genus. Surprisingly, in the P3L118, you made mention to the same sp but the name is not abbreviate. Please, review it.
P3 L107.- “Pot-1”, -1 should be in subscript.
P3 L114.- Is very interesting and productive the combination of PNBS and other microorganism. I suggest that you analyse more in detail the synergistic effect of the inoculation with PBNS. There are many and very interesting studies about it.
P4L133.- Could you explain with more detail how the oxidative stress could be alleviated through the application of antioxidant enzymes externally.
L135.- ALA and 5-ALA are used for the same compound (5-aminolevulinic acid). It must be normalized because is confuse. On the other hand, abbreviation of the 5-ALA is only necessary explain once (See L136-L139).
L135.- Maybe, in this paragraph, you should mention the figure 2 in the text.
L146.- As mentioned above, the genus names and abbreviation must to be review and normalized. Here R. sphaeroides has not been explained before and unknown the genus.
L152.- The explanation of the PNSB treatment (1g in 3L of water) is not enough to made an idea of the assay and its efficiency.
L166.- In relation with the paragraph about heavy metal stress, you should go into detail about the bacterial molecular mechanisms involve in the plant stress reduction.
L194.- Shown instead of shows (in past)
L196.- “not only increased” instead of “will not only increase”
L210.- I suggest that this sentence should be rewritten “No such results were obtained in a similar study by [38].
L212.- Is not clear for me if the variable factor in the assay is the presence or not of rice straw. Please review it “with and without using the rice straw”. What is the role of the rice straw in PNSB inoculations on rice yield? Why is the rice straw use in these assays?
L202-L222 The first half of the point 3 (Research gap) analyses different assays on PNSB inoculation in rice again and is very similar to a several previous points in the manuscript. I suggest review the point in order to avoid redundant tex. A deeper analysis about research gap and more detailed future perspectives are recommendable. Could be interesting analysed what is me best way to PNSB treatment: living cell, dead cell or PSBN extracts; the synergistic interaction with other microorganism,…etc?
Author Response
Dear reviewer,
Thank you very much for your valuable comments and suggestions on our manuscript. We have made the changes to the manuscript based on your comments and suggestions. Here is a brief of what changes we have made.
Comments and Suggestions for Authors
P1 L40.- Citation style must to be normalized. (Sunder and Chen, 2020), this reference is not included in the bibliography.
Citations were improved according to the MDPI style
P1 L41-43. This sentence must to be review. It´s clear the negative effect of climate indicator on plant production. However, from many years ago, it has been described a positive effect of the increment of free air CO2 on photosynthesis and crop yield, mainly in C3 plants. Please review this interesting paper in rice about the topic.
https://doi.org/10.1016/j.scitotenv.2021.151017
The sentence was reviewed, and changes were made according to the provided literature as well as other related articles. Please see lines 41-45
P2 L46.- lower could be changed by slow down the rice development rate and the time….
Changes as suggested. Please see line 48
P2 L53.- thousand-grain weight is a method to quantify the grain size when the grains are small. I suggest that grain size is more proper.
Changes as suggested. Please see line 55
P257.- I would include comparative instead of superlative “a higher warming potential than…”
Changes as suggested. Please see line 58
P2 L78-79.- Ref. 26 remarks to Rhodopseudomonas and Rhodobacter as main group of PNSB, why do you include to Rubrivivax in this category?
We removed Rubrivivax from the category. Please see Figure 1 and lines 101-102
Figure 2.- The figure 2 is not mentioned in the text. It is not common that figure 3 come immediately after the figure 1, P2 L77-L93.
We improved on this and included figure 2 in the text. Please see line 163
P3 L99.- In reference to different papers you use Rhodopseudomonas capsulatus and Rhodobacter capsulatus. Bot names are synonyms of the same type but it can be confused for the reader. I don’t know it is possible formally but I suggest that use only one
Noted, we used one of this throughout the text to maintain consistency
P3 L106.- The sentence about Harada et al. experiments are very interesting but, after review the original paper, the set up explanation could be rewrite in a clearer manner.
The sentence was rewritten for clarity. Please see lines 116-119
P3 L106.- R. palustris is the first time that appear in the text and it must not be abbreviate because the reader unknown the genus. Surprisingly, in the P3L118, you made mention to the same sp but the name is not abbreviate. Please, review it.
Changes have been made accordingly
P3 L107.- “Pot-1”, -1 should be in subscript.
This sentence has been rewritten. Please see lines 116-119
P3 L114.- Is very interesting and productive the combination of PNBS and other microorganism. I suggest that you analyse more in detail the synergistic effect of the inoculation with PBNS. There are many and very interesting studies about it.
A clear discussion on the synergistic effect of the inoculation with PBNS has been added. Please see lines 135-140.
P4L133.- Could you explain with more detail how the oxidative stress could be alleviated through the application of antioxidant enzymes externally.
This part is explained in lines 156-158
L135.- ALA and 5-ALA are used for the same compound (5-aminolevulinic acid). It must be normalized because is confuse. On the other hand, abbreviation of the 5-ALA is only necessary explain once (See L136-L139).
We have made changes accordingly.
L135.- Maybe, in this paragraph, you should mention the figure 2 in the text.
We added this information as suggested
L146.- As mentioned above, the genus names and abbreviation must to be review and normalized. Here R. sphaeroides has not been explained before and unknown the genus.
We have made these changes as well
L152.- The explanation of the PNSB treatment (1g in 3L of water) is not enough to made an idea of the assay and its efficiency.
We have made changes to this sentence. Please see line 176
L166.- In relation with the paragraph about heavy metal stress, you should go into detail about the bacterial molecular mechanisms involve in the plant stress reduction.
This is discussed in lines 184-188
L194.- Shown instead of shows (in past)
We corrected the error. Please see line 217
L196.- “not only increased” instead of “will not only increase”
We corrected the error. Please see line 219
L210.- I suggest that this sentence should be rewritten “No such results were obtained in a similar study by [38].
This sentence has been rewritten with the correct reference. Please see line 233
L212.- Is not clear for me if the variable factor in the assay is the presence or not of rice straw. Please review it “with and without using the rice straw”. What is the role of the rice straw in PNSB inoculations on rice yield? Why is the rice straw use in these assays?
We have included this information in lines 235-239
L202-L222 The first half of the point 3 (Research gap) analyses different assays on PNSB inoculation in rice again and is very similar to a several previous points in the manuscript. I suggest review the point in order to avoid redundant tex. A deeper analysis about research gap and more detailed future perspectives are recommendable. Could be interesting analysed what is me best way to PNSB treatment: living cell, dead cell or PSBN extracts; the synergistic interaction with other microorganism,…etc?
The information provided was carefully screened, and changes were made to avoid repetitions
Author Response File: Author Response.docx
