Increasing Millet Planting Density with Appropriate Fertilizer to Enhance Productivity and System Resilience in Senegal

Round 1

Reviewer 1 Report

This study analyzed the effects of fertilizer combinations on dual purpose verities of millet in different locations. The study is well planned and organized. Overall, manuscript is well written and I would suggest minor revision.

L 116: Hypothesis is weak, please redesign.

L 119: Study objectives should be novel and attractive to the reader. Please rewrite.

L 142: If possible, make a map showing locations or provide geographic coordinates of each location.

Author Response

Response to Reviewers comments

Thanks for your edits, comments, and suggestions. We completed the revisions accepting almost all. Changes we made based on your comments are indicated in track changes in the manuscript. We believe your comments improved the quality and relevance of this manuscript. Please find below a detailed response to each specific comments. We appreciate all the work that you perform daily in order to improve the quality of the Journal and advance scientific reporting.

Reviewer 1

1. This study analyzed the effects of fertilizer combinations on dual purpose verities of millet in different locations. The study is well planned and organized. Overall, manuscript is well written and I would suggest minor revision.

Response: Thank you for constructive comments to our manuscript.

2. L 116: Hypothesis is weak, please redesign.

Response: Comment accepted and our hypothesis “Based on that, we hypothesize that developing site specific fertilizer recommendations across other millet production zones and using fertilizer response functions of new dual purpose millets (SL 28, SL 423 and SL169) will improve yields.”

Is strengthened as follows

“Based on the  previous work, we  hypothesize that developing site specific fertilizer recommendations for other millet production zones and dual purpose millets (SL 28, SL 423 and SL169) varieties will contribute to identifying NPK rates that optimize millet grain and fodder yields  across millet production zones in Senegal.”

3. L 119: Study objectives should be novel and attractive to the reader. Please rewrite.

Response: Comment accepted and our objective “The objective of this study was to determine best agronomic management practices (planting density, variety, and fertilizer rate) for improved dual purpose millet varieties, and create awareness to small holder farmers in Senegal.”

Is rewritten as follows:

“The objective of this study was to determine integrated agronomic management practices (planting density, variety, and fertilizer rate) for improved dual purpose millet varieties, geared towards increased productivity and profitability in millet production zones in Senega.”

4. L 142: If possible, make a map showing locations or provide geographic coordinates of each location.

Response: Comment accepted and map included. Geographic coordinates are given to each location in the materials and methods. “Field experiments were conducted in Bambey (14°43′12″N, 16°36′41″ W; in Diourbel region), Nioro du Rip (13°45′0″N, 15°48′0″ W; in Kaolack region), in Boulel (14°18’18’’N, 15°31’48’’W in Kafrine region) and in Sinthiou Malème (13°51’04’’N, 13°53’04’’; Tambacouda region) in 2021.”

Thanks

Author Response File: Author Response.pdf

Reviewer 2 Report

This study evaluated the grain and biomass production of dual purpose millet varieties grown under different fertilizer rates and planting densities in 4 millet production regions of Senegal. It is an interesting study, however, the presentation of the results is not clear. The results described in the text are not consistent with the statistical results presented in the tables. Please see the specific comments below.

Line 58: Italicize ‘Pennisetum glaucum’

Line 63: Italicize other scientific names used in the manuscript, e.g., Zea mays, Sorghum bicolor

Line 136: How about the temperatures in these two regions?

Line 143: How big was the plot size? How did you prevent potential fertilizer contamination between adjacent fertilizer treatments? Were there any buffer zones between treatments?

Line 150: From Table 1, some fertilizer formula (NPK ratios) or rates are different across the different locations under the same fertilizer treatment, for example D2. How did you decide the rate? Did you take soil samples from each location to analyze soil nutrients before fertilizer treatment?

Line 176: You use ‘DAS’ in Tables instead ‘DAP’, please keep consistent.

Line 176: How many rows in one plot?

Line 252: This is supposed to be Table 2 instead of Table 1.

Line 254: Table 3 instead of Table 2.

Line 234-235: This is not consistent with the results presented in Table 3. From Table 3, at Sinthiou Malème location, there was no significant difference on the total number of tillers among SL 28, SL 423, and Thialack 2 at both planting densities. And there was no significant difference on the total number of fruiting tillers among SL 423, Souna 3, and Thialack 2 at both planting densities.

Line 236: SL 423 was not used in Bambey location.

Line 236-237: This is not consistent with the results presented in Table 3.

Line 238: From Table 2, there was significant interaction between varieties and planting density for SPAD and total tiller number at Bambey location.

Line 239-242: This is not consistent with the results presented in Table 3.

Line 257: Table 4 instead of Table 3

Line 244: From Table 2, at Boulel location, there was no significant fertilizer effect on plant height at 45 DAP. From Table 4, there was no significant difference on plant height between D5 and D1 (control).

Line 246-247: From Table 4, there was no significant difference on plant height at 60 DAP, SPAD, total tiller number and fruiting tiller number among D5, D6, D7, D2, and D3.

Line 247-248: From Table 4, at Sinthiou Malème, there was no significant difference on plant height at 60 DAP among D3, D4, D5, D6, D7, and D8.

Line 249-250: This is not consistent with the results presented in Table 4.

Line 298: Table 5 instead Table 4.

Line 261-263: This is not consistent with the results presented in Table 5. Please present the results based on the statistical analysis results. Please check throughout the manuscript.

Author Response

Response to Reviewers comments

Thanks for your edits, comments, and suggestions. We completed the revisions accepting almost all. Changes we made based on your comments are indicated in track changes in the manuscript. We believe your comments improved the quality and relevance of this manuscript. Please find below a detailed response to each specific comments. We appreciate all the work that you perform daily in order to improve the quality of the Journal and advance scientific reporting.

Reviewer 2

1. This study evaluated the grain and biomass production of dual purpose millet varieties grown under different fertilizer rates and planting densities in 4 millet production regions of Senegal. It is an interesting study, however, the presentation of the results is not clear. The results described in the text are not consistent with the statistical results presented in the tables. Please see the specific comments below.

Response: Thank you for your comments, we have addressed each one of the comments below. Please have a look to each response and let us know if we missed anything.

2. Line 58: Italicize ‘Pennisetum glaucum’

Response: Comment accepted and word italicized

3. Line 63: Italicize other scientific names used in the manuscript, e.g., Zea mays, Sorghum bicolor

Response: Comment accepted and scientific names italicized across manuscript

4. Line 136: How about the temperatures in these two regions?

Response: The average temperature in the regions of Tambacouda and Kaffrine varied from 27°C to 30°C.

 

5. Line 143: How big was the plot size? How did you prevent potential fertilizer contamination between adjacent fertilizer treatments? Were there any buffer zones between treatments?

Response: Sub-sub-plots were 4.5 × 7 m (31.5 m²) comprised of 5 rows for density E1 and 10 rows for density E2. To prevent potential fertilizer contamination between adjacent fertilizer treatments, a buffer zones of 1.5 m were installed around each plot.

 

6. Line 150: From Table 1, some fertilizer formula (NPK ratios) or rates are different across the different locations under the same fertilizer treatment, for example D2. How did you decide the rate? Did you take soil samples from each location to analyze soil nutrients before fertilizer treatment?

Response: The fertilizer combinations evaluated in this study are the best ones identified by Batos et al. [21] in comparison to the control (D1) and the current country recommended inorganic fertilizer rate (D5). The other combinations include D2 (higher grain yield); D3 (higher fodder yield); D4 (higher grain and fodder yield); D6 (current country organo-mineral fertilization recommendation), D7 is D2 plus 25 kg ha-1 of NPK (15-15-15) and D8 which includes D2 plus 50 kg ha^-1 of NPK (15-15-15).

 

7. Line 176: You use ‘DAS’ in Tables instead ‘DAP’, please keep consistent.

Response: Comment accepted and DAS in tables corrected to DAP

 

8. Line 176: How many rows in one plot?

Response: There were 5 rows per plot for the planting density of 12,500 seed hills ha^-1 and 10 rows per plot the planting density of 25,000 seed hills ha^-1

 

9. Line 252: This is supposed to be Table 2 instead of Table 1.

Response: comment accepted and table number corrected

10. Line 254: Table 3 instead of Table 2.

Response: comment accepted and table number corrected

11. Line 234-235: This is not consistent with the results presented in Table 3. From Table 3, at Sinthiou Malème location, there was no significant difference on the total number of tillers among SL 28, SL 423, and Thialack 2 at both planting densities. And there was no significant difference on the total number of fruiting tillers among SL 423, Souna 3, and Thialack 2 at both planting densities.

 

Response: Comment accepted and statement “The highest total number of tillers and the number of fruiting tiller were observed Thialack 2 at 12,500 seed hills ha-1 and Thialack 2 at 25,000 seed hills ha-1, respectively.” Corrected to “The highest total number of tillers and the number of fruiting tiller were observed Thialack 2 at 12,500 seed hills ha-1 and Thialack 2 at 25,000 seed hills ha-1, respectively.” Revised to

“Thialack 2 at 12,500 seed hills ha-1 and Thialack 2 at 25,000 seed hills ha-1 were consistently among the greatest in total number of tillers and in the number of fruiting tiller, respectively, in all location except at Boulel.

 

12. Line 236: SL 423 was not used in Bambey location.

Response: Comment accepted and SL 423 replaced with SL

13. Line 236-237: This is not consistent with the results presented in Table 3.

Response: Comment accepted and sentence revised

14. Line 238: From Table 2, there was significant interaction between varieties and planting density for SPAD and total tiller number at Bambey location.

Response: Comment accepted and sentence “In addition, chlorophyll index and total tiller number were higher at the normal density while the number of fruiting till was higher at the increased density.” Revised to “In addition, chlorophyll index and total tiller number were greater for varieties SL 28, Thialack 2, or Souna 3 at the normal density while the number of fruiting tillers was higher at the increased density for similar varieties at Bambey”

15. Line 239-242: This is not consistent with the results presented in Table 3.

Response: Comment accepted and statement “In Nioro, average height was not significantly different for varieties SL 28, Souna 3 and Thialack 2 at 30 DAP and 45 DAP. The number of fruiting tillers was generally higher at the normal density for all varieties.” Revised to “At Nioro, average height was not significantly different among varieties 30DAP at any planting density and for varieties Souna 3 and Thialack 2 at 45 DAP. The number of fruiting tillers was generally higher at the higher density for all varieties at Nioro.”

16. Line 257: Table 4 instead of Table 3

Response: Comment accepted

17. Line 244: From Table 2, at Boulel location, there was no significant fertilizer effect on plant height at 45 DAP. From Table 4, there was no significant difference on plant height between D5 and D1 (control).

Response: Comment accepted and statement “There was no significant influence of fertilization on plant height at 30 DAP. However, at 45 DAP, fertilization influenced millet height only at Boulel, and the highest height was observed with D5, which was 25% higher compared with the control (D1: 0N-0P-0K).” corrected to state “There was no significant influence of fertilization on plant height at 30 and 45 DAP”

18. Line 246-247: From Table 4, there was no significant difference on plant height at 60 DAP, SPAD, total tiller number and fruiting tiller number among D5, D6, D7, D2, and D3.

Response: Comment accepted and “Likewise, D5, D6 and D7 gave the highest height at 60 DAP, chlorophyll index, total tiller number and fruiting tiller number” reworded to say “At Boulel, D5 gave the highest height at 60 DAP compared with D8, greatest chlorophyll index and total tiller number compared with D1, and great fruiting tiller number compared with D4.”

19. Line 247-248: From Table 4, at Sinthiou Malème, there was no significant difference on plant height at 60 DAP among D3, D4, D5, D6, D7, and D8.

Response: Yes, and this information is included in revised manuscript

20. Line 249-250: This is not consistent with the results presented in Table 4.

Response: Comment accepted and statement “At Bambey and Nioro, D5, D6, D7 and D8 gave the highest average heights as well as chlorophyll index, total tiller number and fruiting tiller numbers.” Revised to indicate “At Bambey and Nioro, D1 (the control treatment) resulted in consistently lower average heights as well as chlorophyll index, total tiller number and fruiting tiller numbers than top performing treatments.”

 

21. Line 298: Table 5 instead Table 4.

Response: Comment accepted

22. Line 261-263: This is not consistent with the results presented in Table 5. Please present the results based on the statistical analysis results. Please check throughout the manuscript.

Response: Comment accepted and paragraph revised

 

Thanks!

Author Response File: Author Response.pdf

Reviewer 3 Report

General note:

The subject of the study is very interesting and topical, with scientific and practical importance.

The introduction is presented correctly and in accordance with the subject. Numerous scientific articles, in concordance to the topic of the study, were consulted.

The study’s methodology was clearly presented, and appropriate to the proposed objectives.

The obtained results are important and have been analyzed and interpreted correctly, in accordance with the current methodology.

The discussions are appropriate, in the context of the results, and were conducted compared to other studies in the field.

The scientific literature, to which the reporting was made, is recent and representative of the field.

Authors should revise the reference list by following the rules described in the guidelines for authors.

There are some minor changes I am suggesting in the detailed comments below.

Line 23 – there is “ha-1” please insert superscript. Check and correct throughout the manuscript

Table 2 – “. For each variable, means followed by same letter are not significantly different, Tukey test, p < 0.05.” - I propose to move this sentence under the table.

Section - 3.2. Influence of varieties, sowing density, and fertilization on millet yield - Authors should consider removing data (yields) from the text. These data are in figures. Alternatively, yields can be given in t/ha rather than kg/ha.

Lines 291 -296 - Please check the correctness of this paragraph

Table 6 - Please improve the format of this table

Author Response

Response to Reviewers comments

Thanks for your edits, comments, and suggestions. We completed the revisions accepting almost all. Changes we made based on your comments are indicated in track changes in the manuscript. We believe your comments improved the quality and relevance of this manuscript. Please find below a detailed response to each specific comments. We appreciate all the work that you perform daily in order to improve the quality of the Journal and advance scientific reporting.

Reviewer 3

1. The subject of the study is very interesting and topical, with scientific and practical importance. The introduction is presented correctly and in accordance with the subject. Numerous scientific articles, in concordance to the topic of the study, were consulted. The study’s methodology was clearly presented, and appropriate to the proposed objectives. The obtained results are important and have been analyzed and interpreted correctly, in accordance with the current methodology. The discussions are appropriate, in the context of the results, and were conducted compared to other studies in the field. The scientific literature, to which the reporting was made, is recent and representative of the field. Authors should revise the reference list by following the rules described in the guidelines for authors. There are some minor changes I am suggesting in the detailed comments below.

Response: Thank you for your constructive comment. We have revised reference according to guidelines for author and find below response for each comments.

 

2. Line 23 – there is “ha-1” please insert superscript. Check and correct throughout the manuscript

Response: comment accepted and “-1” in “ha-1” is superscripted across the manuscript

3. Table 2 – “. For each variable, means followed by same letter are not significantly different, Tukey test, p < 0.05.” - I propose to move this sentence under the table.

Response: Comment accepted and statement moved from table caption to to under table

4. Section - 3.2. Influence of varieties, sowing density, and fertilization on millet yield - Authors should consider removing data (yields) from the text. These data are in figures. Alternatively, yields can be given in t/ha rather than kg/ha.

Response: To keep text and table to stand alone, we kept yield data in text as it is.

5. Lines 291 -296 - Please check the correctness of this paragraph

Response: We checked and paragraph is correct “Table 6 summarizes the correlation coefficients between grain and fodder and growth parameters. The chlorophyll index, total number of tillers and number of fruiting tillers were positively and significantly correlated with grain and fodder yield at most sites. This means that as the values of these parameters increase, grain yield and fodder yield also increase. The correlation is particularly high (˃70%) between the number of fruiting tillers and grain yield for all sites.”

6. Table 6 - Please improve the format of this table

Response: format of table 7 (old table 6) is now improved

 

Thanks!

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

All the deleted texts were not marked as deleted, which makes it difficult to distinguish between deleted and non-deleted text.

Line 163: delete “ing” after “of”

Line 255-258: you stated, “In addition, chlorophyll index and total tiller number were greater for varieties SL 28, Thialack 2, or Souna 3 at the normal density while the number of fruiting tillers was higher at the increased planting density for similar varieties at Bambey”. This is not consistent with the statistical results presented in Table 3.

Please carefully check throughout the manuscript to ensure consistency between the text and the tables to avoid confusion and maintain accuracy in the reporting of the research.

Author Response

Thank you for your comments, we have addressed them and we believe the manuscript is improved because of your feedback. Please have a look at our responses and let us know if we missed anything.

1. All the deleted texts were not marked as deleted, which makes it difficult to distinguish between deleted and non-deleted text.

Response: We have submitted a track change and clean version of the revised manuscript. Sorry but we did not know why you couldn’t see deleted vs non-deleted text. In this version we have accepted all previous changes and only the minor changes in this review remain. Therefore, we believe now you can easily see changes.

2. Line 163: delete “ing” after “of”

Response: Comment accepted

3. Line 255-258: you stated, “In addition, chlorophyll index and total tiller number were greater for varieties SL 28, Thialack 2, or Souna 3 at the normal density while the number of fruiting tillers was higher at the increased planting density for similar varieties at Bambey”. This is not consistent with the statistical results presented in Table 3.

Response: Comment accepted and we made change on order of varieties. But basic idea of the statement is correct according to Table 3. (Chlorophyll index at normal density was 60.84a, 59.12a for varieties SL 28 & Thialack 2; Tiller number was 16.31a and 15.89a for varieties Souna 3 and Thialack 2, respectively).

Sentence revised to “In addition, chlorophyll index and total tiller number were greater for varieties Thialack 2 and SL 28, or Thialack 2 and Souna 3, respectively, at the normal density while the number of fruiting tillers was more at increased planting density for same (Thialack 2, SL 28, and Souna 3) varieties at Bambey”

4. Please carefully check throughout the manuscript to ensure consistency between the text and the tables to avoid confusion and maintain accuracy in the reporting of the research.

Response: Comment accepted and manuscript checked for text-table consistency.

 

Thanks!

Author Response File: Author Response.pdf