Alleviation of Water-Deficit Stress on Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer

Round 1

Reviewer 1 Report

Dear authors

Please consider following major comments:

1-You described about effects of SAPs on seed properties generally. Are these effects based on kind of seed? If so, please add it in introduction section.

2-In lines 62, 82 and so on, please correct the sentences and put the reference at the end of sentence.

3-What kind of SAP did you use, hydrogels or other categories? What kind of polymer was used for fabrication of it? Please add related description completely, in Materials and Methods section.

4-What is reason of SAP effect differences between barley and fenugreek seeds?

5-There are spelling and grammatical errors that must be corrected.

Sincerely

 

 

 

There are spelling and grammatical errors that must be corrected.

Author Response

Manuscript ID: Agronomy-2554960

Manuscript Title:  "Alleviation of Water-Deficit Stress and Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer"

=========================================

Dear Reviewer

         Thank you for your efforts and I would like also to thank very much the reviewers for their valuable comments. Where I am very happy that our manuscript was satisfied with you, and I have the great honor to publish in your valuable journal. We have corrected the manuscript based on the comments of reviewers, and the corrections made in the text in red color, and are outlined step by step as follows:

Response to the comments of Reviewer 1:

Thank you for the positive consideration and feedback of the manuscript. We have revised the manuscript thoroughly in light of the reviewers

 

• You described about effects of SAPs on seed properties generally. Are these effects based on kind of seed? If so, please add it in introduction section.

Re. Thank you for the suggestion, the description about SAPs added in lines 98-103.

• In lines 62, 82 and so on, please correct the sentences and put the reference at the end of sentence.

Re. Thank you for the note. The sentences were corrected and the reference was added at the end of the sentence (lines 67-69 and lines (88-91).

• What kind of SAP did you use, hydrogels or other categories? What kind of polymer was used for fabrication of it? Please add related description completely, in Materials and Methods section.

Re. Thank you for the question. The answers were done in line 113.

• What is reason of SAP effect differences between barley and fenugreek seeds?

Re. Thank you for the question. Actually, the seed's germination is a function of several abiotic parameters such as soil temperature, soil water contents, and type of seeds. So, any factor such as SAP leads to an increase in the available soil water content and can boost the seeds' germination percentages Lines 290-293).

• There are spelling and grammatical errors that must be corrected.

Re. Thank you for your valuable suggestions. done. We carefully checked the entire manuscript and polished the language to improve the readability and avoid possible grammatical and syntax errors.

Again, many thanks for the careful reviews.

Summarizing, we have revised the manuscript according to the annotations of the reviewer and we are looking forward to your response.

Best regards

The authors

 

Reviewer 2 Report

The objective of this study was to investigate the potential effect of three rates of superabsorbent polymers (SAPs) in the enhancement of seed germination in sand soil using different parameters.  There are some comments and suggestions to be made to improve the article:

 Introduction:

 1. In lines 42 and 43, the authors say that population growth is the greatest obstacle to the development of sustainable agriculture. It seems to me that there are other factors that the authors should mention, such as the conservation of soil, water, and animal and plant genetic resources, in addition to organic agriculture, integrated agricultural production, agroforestry production, and crop-livestock-forest integration.

 2.In lines 45 and 46, the authors say that approaches to improve land productivity and maximize crop production pass through the soil's ability to retain water; it is known that it is not just for that reason; the authors should cite other ways to increase crop production.

 3. In lines 52 and 53, the authors say that SAP application in agriculture has been used since 1950; the authors should put references about it, exemplifying the type of polymer used.

 4.Line 93 - the authors say that there are few references about seed germination of barley and fenugreek crops; the few references should be cited then.

 Materials and Methods:

 1. Should the authors say what kind of SAP was used in the work - absorbent polymers, water gels, or hydrogels? And what polymer was used in the work?

 2. In lines 107 and 108, the authors say that different amounts of SAP were mixed with air-dried sand soil; is this soil the same as the authors mention in item 2.1.1, lines 125 and 126?

 3. It would be important to explain eq. Romanenko to better understand the amount of water that was used in Table 1, which is given in cm.

 4. The values found in Table 4 should be better discussed, shouldn't the increase in SAP concentration improves the germination parameters? The authors textually state in line 217 that It is obvious that SAP accelerated the germination process in comparison to the control case (...)” - wouldn't that be a contradiction about the results found?

 5. What considerations can be made concerning the composition and/or characteristics of the different seeds (barley and fenugreek) and their impact on the results obtained?

 6. In Figure 1, it should be explained why at the 1% concentration of SAP, the germination time was longer than at the 0.5% concentration.

 7. On lines 251 and 252, the authors should discuss and better explain the sentence that said as follows: “Generally, the greatest values for all germination parameters times were obtained with 0.0% SAP while the 0.5% and 1.0% SAPs gave the lowest values in both cases.”

 Discussion:

 1. On line 270, correct where it says Table 3, it is Table 4.

 

The English language should be improved; there are some mistakes in the text.

Author Response

Manuscript ID: Agronomy-2554960

Manuscript Title:  "Alleviation of Water-Deficit Stress and Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer"

=====================================================================

Dear Reviewer

         Thank you for your efforts and I would like also to thank very much the reviewers for their valuable comments. Where i am very happy that our manuscript was satisfied with you, and i have the great honor to publish in your valuable journal. We have corrected the manuscript based on the comments of reviewers, and the corrections made in the text in red color, and are outlined step by step as follows:

Response to the comments of Reviewer 2:

 

Thank you, indeed, for the valuable comment and suggestion.As suggested by the reviewer, we thoroughly and carefully revised and updated the manuscript as mentioned below point by point.

• Introduction
• In lines 42 and 43, the authors say that population growth is the greatest obstacle to the development of sustainable agriculture. It seems to me that there are other factors that the authors should mention, such as the conservation of soil, water, and animal and plant genetic resources, in addition to organic agriculture, integrated agricultural production, agroforestry production, and crop-livestock-forest integration.

Re. Thank you very much for the valuable comment. Your comment has been taken into account in lines 43-46.

• In lines 45 and 46, the authors say that approaches to improve land productivity and maximize crop production pass through the soil's ability to retain water; it is known that it is not just for that reason; the authors should cite other ways to increase crop production.

Re. Thank you very much for your suggestion. (Done in lines 49-52).

• In lines 52 and 53, the authors say that SAP application in agriculture has been used since 1950; the authors should put references about it, exemplifying the type of polymer used.

Re. Thank you very much for your careful review. (Done in line 59).

• Line 93 - the authors say that there are few references about seed germination of barley and fenugreek crops; the few references should be cited then.

Re. Referring to the literature, it was found that there were no studies associated with the effect of SAPs on the germination seeds of both barley and fenugreek. Therefore, the sentence was written again as shown in lines 102-103.

• Materials and Methods
• Should the authors say what kind of SAP was used in the work - absorbent polymers, water gels, or hydrogels? And what polymer was used in the work?

Re. Thank you for the note. The kind of SNP mentioned in line 119.

• In lines 107 and 108, the authors say that different amounts of SAP were mixed with air-dried sand soil; is this soil the same as the authors mention in item 2.1.1, lines 125 and 126?

Re. Thank you for the question. Yes, the same type of soil.

• It would be important to explain eq. Romanenko to better understand the amount of water that was used in Table 1, which is given in cm.

Re. The Romanenko’s model used is: ET=0.0018(25+Ta)2(100-hm). Wheras ET is evaporation rate from water (mm/month). Ta is air temperature in C, and hm is relative humidity (%) (Line 132 – 134).

• The values found in Table 4 should be better discussed; shouldn't the increase in SAP concentration improve the germination parameters? The authors textually state in line 217 that It is obvious that SAP accelerated the germination process in comparison to the control case (...)” - wouldn't that be a contradiction about the results found?

Re. Thank you for the question. It is obvious that 0.0% SAP provided the greatest FGP in barley in comparison to the other SAP levels. The SAP might release the water to seed slowly that reduce the FGP in SAP treated soils. However, the FGP in barley seeds were not significant among the three SAP levels. The corresponding values for the fenugreek were 76.67%, 86.67%, and 80%. The differences among the SAP levels were not significant as in the barley seeds as well (lines 241-246).

• What considerations can be made concerning the composition and/or characteristics of the different seeds (barley and fenugreek) and their impact on the results obtained?

Re. Thank you for the question. According to the results of barley seeds germination (Fig. 1), using 0.5 and 1.0% SAP is enough to get high percentage of germination. While for seed germination of fenugreek, using 0.5% SAP is recommended since the germination percentage was high in comparison to 1.0% SAP.

• In Figure 1, it should be explained why at the 1% concentration of SAP, the germination time was longer than at the 0.5% concentration.

Re. Thank you for the observation. As illustrated in figure (1), the germination time at 0.5 and 1.0% SAP was equal for barley seeds while the germination time at 1.0% SAP was less than the its value for 0.5% SAP for fenugreek. These results are due to the available water for seed germination under 1.0% SAP is higher than under 0.5% SAP (Line 295-298).

• On lines 251 and 252, the authors should discuss and better explain the sentence that said as follows: “Generally, the greatest values for all germination parameters times were obtained with 0.0% SAP while the 0.5% and 1.0% SAPs gave the lowest values in both cases.”

Re. Thank you for the suggestion. Generally, the greatest values for the germination parameters (T50 and Tmax) were obtained with the untreated SAP soil, while the 0.5% and 1.0% SAPs gave the lowest values (lines 275-277).

• Discussion
• On line 270, correct where it says Table 3, it is Table 4.

Re. Thank you for the correction, we changed it the revised version of the manuscript (line 281).

Comments on the quality of English Language. The English language should be improved; there are some mistakes in the text.

Thank you for your valuable suggestions. We have revised the manuscript language thoroughly and addressed the reviewers' comments accordingly.

Again, many thanks for the careful reviews.

Summarizing, we have revised the manuscript according to the annotations of the reviewer and we are looking forward to your response.

Best regards

The authors

 

Author Response File: Author Response.doc

Reviewer 3 Report

The research article " Alleviation of Water-Deficit Stress on Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer" investigates the potential effect of three rates of SAPs (0.0%, 0.5%, and 1.0 % w/w) on the seedling emergence of barley and fenugreek sown in a sand soil using three replicates in a randomized complete block design. In order to increase the usefulness and significance of the study, the author needs to address the following issues given below.

 

In the introduction section, it is recommended that the rationale of the research must be incorporated in the form of the figure.

In result and discussion section needs more justification by comparing similar studies (especially by using recent literature).

There are a few grammatical errors that must be checked before submitting the revision.

Use consistent style in Table presentation.

Author Response

Manuscript ID: Agronomy-2554960

Manuscript Title:  "Alleviation of Water-Deficit Stress and Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer"

=====================================================================

Dear Reviewer

Thank you for your efforts and I would like also to thank very much the reviewers for their valuable comments. Where I am very happy that our manuscript was satisfied with you, and I have the great honor to publish in your valuable journal. We have corrected the manuscript based on the comments of reviewers, and the corrections made in the text in red color, and are outlined step by step as follows:

Response to the comments of Reviewer 3:

Response: Thank you very much for the valuable suggestions and useful comments. Following to those suggestions/comments, we thoroughly and carefully revised and updated the manuscript as mentioned below, point-by-point.

• In the introduction section, it is recommended that the rationale of the research must be incorporated in the form of the figure.

Re Thank you for your valuable suggestions.  Done.

• In result and discussion section needs more justification by comparing similar studies (especially by using recent literature).

Re Thank you for your valuable comment. In accordance with the comments of other reviewers, I would like to inform you that we have made some adjustments as shown in lines 262-267; 300-302; 323-327, and 334-338. In addition, we tried to cite more recent references than what is in the manuscript, but the studies conducted on the effect of polymers on seed germination parameters were somewhat few.

• There are a few grammatical errors that must be checked before submitting the revision.

Re: The manuscript was well-revised to correct the grammatical errors.

• Use consistent style in table presentation.

Re Thank you for the suggestion, All presentation tables have been reviewed, whether in the materials and methods section (Tables 1, 2, and 3) or in the results section (Tables 4 and 5), using a consistent style.

 

We are once again grateful for your valuable time and comments and hope that you may find that we have satisfactorily modified all the sections and improved the language of the Ms following your kind comments and suggestion.

Reviewer 4 Report

Comments can be found on the pdf document

Comments for author File: Comments.pdf

Author Response

Manuscript ID: Agronomy-2554960

Manuscript Title:  "Alleviation of Water-Deficit Stress and Seed Germination of Barley and Fenugreek in a Sandy Soil Using Superabsorbent Polymer"

=====================================================================

Dear Reviewer

         Thank you for your efforts and I would like also to thank very much the reviewers for their valuable comments. Where i am very happy that our manuscript was satisfied with you, and i have the great honor to publish in your valuable journal. We have corrected the manuscript based on the comments of reviewers, and the corrections made in the text in red color, and are outlined step by step as follows:

Response to the comments of Reviewer 4:

• The paper is well written, and results are clearly shown, it does not provide sufficient new research to the field. Authors say so from line 58 of the introduction.

Thank you for the positive consideration and feedback of the manuscript. We have revised the manuscript thoroughly in light of the reviewers

• Are SAPs toxic? Is your SAP toxic?

Re. Thank you for the question. Some studies indicated that some of these materials may be toxic due to their slow biodegradation in soil. Bearing in mind that the use of sodium polyacrylate as one of the SAPs did not result in any toxicity, this was not indicated in any of the previous studies that relied on the use of sodium polyacrylate. 

• What SAP did you use? It is not possible to say? Then state it.

Re. Sodium polyacrylate (line 126)

• You could also indicate which type according to references 27.

Re. The type is a hydrogel.

• Is the use of SAP economically viable? Does it reduce the cost to farmers?

Re. Yes, it is ecumenically using the SAP because its water saturation is greatly high that = 231.5 g water/g SAP.

 

• Why wasn’t the yield of both species analyzed? One thing is for SAPs to alleviate germination but what impact does that have on production.

Re. It is a good remark by the reviewer, this remark might be a future research point by another or another.

 

• I honestly feel that the article lacks novelty, I encourage author to resubmit to another journal or to prepare more data for their evaluations.

Re. OK but the presented article showed enough justified data such using several evaluation parameters (FGP, GI, polynomial equation and it first derivation for monitor the temporal variation of germination). Additionally, a new concept (The Water Germination Efficiency (WGE) was used in the present study

Content related comments.

Table 1. Why aren’t there *and ** for barley? Was this just for fenugreek?

Re. Table (1) shows the amount of applied water for both crop seeds based on Romanenko’s equation (1961)

Table 1. Is time, time after sowing? If so, state it pleases.

Re. OK done, Additionally, to maintain adequate soil moisture for seed imbibition of water, some tap water was periodically added to each pot after sowing (Table 1) according to [35,36] Romanenko’s equation (1961) (cf. Xu and Singh, 1998), until achieving final seed germination.

Table 1. water is indicated as cm when for SAPs the unit is g of water per g of SAP. Could you change cm to g? Easier to follow.

Re. Thank you for your valuable comment, Usually, soil scientists express the soil water in gravimetric, volumetric, or unit cm.  The latter is much preferred in the design of irrigation systems such as drip or sprinkler irrigation systems.

Table 4. I can understand that GI is a better measure for germination than FGP. But why does FGP is higher without SAP/ is SAP somewhat toxic? This is crucial for farming. If not all the seeds germinated it must be understood why.

Re. It is an excellent remark by an excellent reviewer.  The SAP is not toxic at all but mixing the SAP with soil at low water content made a crust layer that hindered the seed for germination processes. Additionally, the saturated hydraulic conductivity of soil -the SAP mixture is low which reduces the seed imbibition water.

Table 4 and Figure 1. For fenugreek as per GI 0.5 SAP is better, however, they germinated faster.

Re. Yes, GI is high implying high speed. The following is quoted from the article “Therefore, the GI emphasizes both the percentage of germination and its speed [42]. A higher GI value denotes a higher percentage and rate of germination.”

What’s the explication behind this? The difference in GI is small, is that low number good compared to germinating two days later?

Re. This is the definition of GI, Therefore, the GI emphasizes both the percentage of germination and its speed [42]. A higher GI value denotes a higher percentage and rate of germination. It means the germination in a short time gives a high (GI).

Line 323. Authors say that SAP-treated soil enhanced cotyledon’s protrusion but that was not measured not shown.

Re. Table 4: shows high GI in the SAP-treated soil in comparison to the untreated soil. So, we believe that SAP enhanced the seed germination for both species.

Line 325. Authors say that SAP is a promising solution for boosting germination of barley and fenugreek but it is already know that SAP boost germination. What makes this SAP, which we know nothing about so special.

Re. The research of this article was archived in an arid region in Egypt (Table 2). By using this kind of superabsorbent polymer (SAP), the germination of both seeds was good which encourage the farmers to use this kind of technology.

Format related comments

Line 69. Authors name and publication year should be included instead of the reference number.

Line 82. Same comment.

Re. For references in lines 62 and 82, I would like to inform you that both references are placed at the end of the sentence according to the comments of one of the reviewers.

Review this for similar instance.

Line 91. Species name should be italicized.

Re. Thank you for the note, done

Figure 1 (a) and (b). it seems that the figure got resized in a bad manner. Plus, they are not the same size.

Re. Thank you for the note, done

 

Again, many thanks for the careful reviews.

Summarizing, we have revised the manuscript according to the annotations of the reviewer and we are looking forward to your response.

Best regards

The authors

Round 2

Reviewer 1 Report

Dear authors

The manuscript can be acceptable.

Sincerely

It is OK.

Reviewer 4 Report

I thank the authors for all the corrections they've made. However I do not find the findings sufficient to support the novelty of their study. Moreover, they still claim that SAPs have been used quite a time already.
I encourage you to submit to another journal.