Broccoli Cultivation Under Different Sources and Rates of Specialty Phosphorus Fertilizers in the Brazilian Cerrado

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

While the study addresses a relevant and timely topic in sustainable vegetable production, several important concerns regarding experimental description, interpretation of data, and scientific terminology need to be addressed to strengthen the manuscript:

Title and Keywords: The term "physicochemical attributes" used in the keywords is vague and not directly linked to the main goal of the paper. Consider aligning the keywords more specifically with measurable variables such as “soil fertility”, “foliar nutrient content”, “broccoli yield”, and “fertilizer efficiency”.

Abstract: The abstract omits critical quantitative results. Since yield increases by percentages are discussed in the main text, these should also be reflected concisely in the abstract to improve clarity and impact. Either report the percentage increases consistently or provide the absolute values for all treatments mentioned.

Introduction: The discussion of broccoli yield and production increases should clarify whether it refers to Brazil or other regions. The introduction should be more focused on identifying the production challenges related to phosphorus management in the Cerrado and should better connect the study's goals with the gaps in current fertilization strategies. Extensive general background on broccoli is unnecessary; more precise framing of the study’s objectives would improve readability.

Clarify why broccoli was transplanted following cabbage. Present the experimental site's description clearly and early. Use metric units consistently, define all abbreviations in tables and figures, and clarify if rainfall values represent totals or averages.

Broccoli Transplants:

Include cultivar type, seed source, and typical yield. State the biomass amounts removed after cabbage and before broccoli planting.

Yield Estimation:

Clarify yield estimation methods and avoid mixing units (e.g., kg/plant vs. Mg/ha).

Dry Matter/Nutritional Assessment:

Specify number of plants used for dry matter analysis. Clearly distinguish between broccoli head and leaf analyses. Use 'nutritional composition' instead of 'chemical attributes'.

Data Interpretation:

Percentages should use numerals followed by '%'. Define 'SMP' in Table 1. Use consistent notation for ions (e.g., H^- and Al³⁺, or H and Al without signs, but not mixed). Terms like 'mass' and 'yield' must be used accurately.

Specific Comments

Line 35: Revise keywords—'physicochemical attributes' is overly broad.

Lines 17–34: Include specific data values (NL, FHW, DHW, YLD) in the abstract for all fertilizer treatments to enable comparison.

Lines 37–91 (Introduction): Clarify the regional scope of production statistics and streamline the introduction.

Lines 93–108: Start methods with the site description and soil classification.

Lines 144–147: Clearly identify if 'Avenger' is a hybrid and specify seed source.

Tables 2, 4, 5, 6: Ensure all abbreviations are defined fully. Convert imperial to metric units.

Figure 2: Clarify whether the data shown refer to totals or averages.

Line 173: Clarify if 'expected yield of 20 Mg/ha' is a standard regional value or derived from previous experiments. Additionally, the use of 'Mg/ha' (megagrams per hectare) should be explained—is it referring to marketable broccoli heads, total aboveground biomass, or a theoretical benchmark? The term 'yield' must be clearly defined in context to avoid confusion.

Comments on the Quality of English Language

Acceptable (minor language edits needed)

Author Response

REVIEWER 1

                                                                                      Uberaba, Minas Gerais, Brazil: 26/05/2025

  Corrections made to the text

 

Title and Keywords: The term "physicochemical attributes" used in the keywords is vague and not directly linked to the main goal of the paper. Consider aligning the keywords more specifically with measurable variables such as “soil fertility”, “foliar nutrient content”, “broccoli yield”, and “fertilizer efficiency”.

- The keywords have been changed.

 

Abstract: The abstract omits critical quantitative results. Since yield increases by percentages are discussed in the main text, these should also be reflected concisely in the abstract to improve clarity and impact. Either report the percentage increases consistently or provide the absolute values for all treatments mentioned.

- The percentage values have been inserted in the summary

 

Introduction: The discussion of broccoli yield and production increases should clarify whether it refers to Brazil or other regions.

The text states that the increase in broccoli production is taking place in Brazil and its regions.

 

The introduction should be more focused on identifying the production challenges related to phosphorus management in the Cerrado.

- The state that in the Brazilian cerrado, the soils are weathered and acidic, with mineralogy rich in iron (Fe) and aluminium (Al) oxides, as well as kaolinite. This favors high phosphate adsorption due to the presence of positive charges on the surface of these oxides, where the main challenges for crop production lie

- It also highlighted the new fertilizer technologies that are being tested to minimize the losses that occur through adsorption and erosion, and the lack of natural fertility of the soils that occur in the Brazilian cerrado.

 

Should better connect the study's goals with the gaps in current fertilization strategies. Extensive general background on broccoli is unnecessary; more precise framing of the study’s objectives would improve readability.

- The information highlighted in the introduction/review was connected by highlighting the hypothesis tested, which was reformulated, questioning whether special fertilizers (FOs and POLs) are more efficient at supplying phosphorus for broccoli production in the Cerrado's weathered soils, when compared to traditional mineral fertilizers.

 

- The aim of this study was to evaluate the agronomic performance of broccoli grown under different doses and sources of special phosphorus fertilizers in Uberaba, MG.

 

Clarify why broccoli was transplanted following cabbage. Present the experimental site's description clearly and early.

- As for the history of the experimental area, it had been used in other studies with brassicas (cauliflower, cabbage and broccoli), and the last crop planted was cabbage, but the area was left fallow for a year, after which all the soil was prepared with a heavy harrow and a light harrow, before the new broccoli study was implemented.

 

Use metric units consistently, define all abbreviations in tables and figures, and clarify if rainfall values represent totals or averages.

- The necessary adjustments were made to better locate the area in a clear and objective way.

 

Broccoli Transplants:

Include cultivar type, seed source, and typical yield.

- The information was included in the methodology

 

State the biomass amounts removed after cabbage and before broccoli planting.

-The area had been fallow for a year and the biomass of this vegetation was not quantified, as it was all incorporated into the soil preparation with two harrowing operations (plowing and leveling) that was carried out, as described in the text.

 

Yield Estimation:

Clarify yield estimation methods and avoid mixing units (e.g., kg/plant vs. Mg/ha).

- The estimation methods were inserted into the text and the units were corrected, keeping only the crop yield in Mg ha^-1.

 

Dry Matter/Nutritional Assessment:

 

Specify number of plants used for dry matter analysis. Clearly distinguish between broccoli head and leaf analyses.

-The methodology specified

 

Use 'nutritional composition' instead of 'chemical attributes'.

The changes have been made to the text

 

 

Data Interpretation:

Percentages should use numerals followed by '%'.

-Corrections made.

Define 'SMP' in Table 1.

-The term has been defined in the table

 

Use consistent notation for ions (e.g., H- and Al³⁺, or H and Al without signs, but not mixed). Terms like 'mass' and 'yield' must be used accurately.

-Corrections made.

 

Specific Comments:

Line 35: Revise keywords—'physicochemical attributes' is overly broad.

-The word has been replaced by another

 

Lines 17–34: Include specific data values (NL, FHW, DHW, YLD) in the abstract for all fertilizer treatments to enable comparison.

- Values included in the summary and conclusions

 

Lines 37–91 (Introduction): Clarify the regional scope of production statistics and streamline the introduction.

-The regional data has been removed from the introduction as it was unnecessary.

 

Lines 93–108: Start methods with the site description and soil classification.

-Corrected in the text

 

Lines 144–147: Clearly identify if 'Avenger' is a hybrid and specify seed source.

-Corrected in the text

 

Tables 2, 4, 5, 6: Ensure all abbreviations are defined fully. Convert imperial to metric units.

-All abbreviations have been checked

 

Figure 2: Clarify whether the data shown refer to totals or averages.

- It has been clarified in the text

 

 

Line 173: Clarify if 'expected yield of 20 Mg/ha' is a standard regional value or derived from previous experiments.

-This is a value defined for the state of Minas Gerais by Ribeiro et al. (1999), who inserted the information in the text.

 

Additionally, the use of 'Mg/ha' (megagrams per hectare) should be explained—is it referring to marketable broccoli heads, total aboveground biomass, or a theoretical benchmark? The term 'yield' must be clearly defined in context to avoid confusion.

-The productivity of marketable broccoli heads was quantified in Mg ha-1, which has been corrected in the text.

            I would like to thank the reviewer for his suggestions on improving the quality of the article, all of which have been taken on board and inserted into the body of the text:

 

José Luiz Rodrigues Torres

Corresponding author

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This study employs scientific experimental design and multidimensional analysis to investigate the effects of different sources and application rates of specialty phosphorus fertilizers on broccoli's agronomic performance and yield. The work demonstrates both theoretical innovation and practical significance, providing valuable references for phosphorus management in vegetable production within Brazil's Cerrado region. The manuscript is well-structured with clearly presented methodology, results, and discussion. However, several revisions are required to enhance the scientific rigor and clarity. Specific recommendations for improvement include:

1. Correct "atributes" to "attributes" to ensure terminological accuracy（Line 35）.
2. The abbreviation of SMP in Table 1 is not fully explained. It is recommended to add (Lines 115–116).
3. Clarify whether the maximum FHW value of 1.35 kg at 376 kg ha⁻¹ P₂O₅ (94.5%) was derived from regression models or direct measurements. Explicitly state the methodological basis for this conclusion（Lines 273–275）.
4. Inter-season management:Were there any other agricultural operations during the interval between the two test seasons? For example, stubble clearing measures, tillage, etc. It is recommended to state it clearly to reduce the possibility of residual factors.
5. The organic matter content of “granular organomineral fertilizer (Org) (formula 05-26-00)” is not provided, which may affect the reader’s understanding of its mechanism of action to some extent（Line 130）.
6. Language polishing:The English grammar and vocabulary throughout the paper need some improvement from the author so that the readers can read it smoothly.
7. Statistical notation: It is recommended that the (** = p < 0.05; * = p < 0.01) in the notes below all tables in the text be replaced with (*p<0.05, **p<0.01). This will make the expression more standardized and avoid misunderstanding among readers (Lines 246–247; 322–323; 368–369; 449–450; 481–482).
8. PCMP performance dynamics:PCMP treatment had an obvious advantage in the first season, but declined in the second season. Is it because the change in soil pH affected the degradation rate of the fertilizer coating? In this part, the author is advised to make a speculative analysis by citing the research results of others to improve the integrity of the article.

Residual effect evaluation: The current assessment of Org's residual effects based solely on soil nutrient data appears limited. Incorporating supplementary biological indicators (e.g., soil microbial activity, enzyme assays) would strengthen the evidence through multidimensional quantification.

Author Response

REVIEWER 2

                                                                Uberaba, Minas Gerais, Brazil: 26/05/2025

Corrections made to the text

Specific recommendations for improvement include:
Correct "atributes" to "attributes" to ensure terminological accuracy（Line 35).
- Word replaced at the request of the other reviewer.

The abbreviation of SMP in Table 1 is not fully explained. It is recommended to add (Lines 115–116).
- Abbreviation explained

Clarify whether the maximum FHW value of 1.35 kg at 376 kg ha⁻¹ P₂O₅ (94.5%) was derived from regression models or direct measurements. Explicitly state the methodological basis for this conclusion（Lines 273–275.
- It was explained that from the equation of the regression curve it was possible to calculate the maximum MFC of 1.35 kg, at a dose of 376 kg ha-¹ P₂O₅ (94.5%) of the fertilizer used.

Inter-season management:
Were there any other agricultural operations during the interval between the two test seasons? For example, stubble clearing measures, tillage, etc. It is recommended to state it clearly to reduce the possibility of residual factors.
-Part of this is already included in the text of the article:

In preparing the area, two harrowings were carried out, one heavy and deeper with a harrow of 18 30-inch discs, the other superficial with a leveling harrow of 44 24-inch cut-out discs, for the next being the digging and subsequent transplanting of the broccoli seedlings (Brassica oleracea var. itálica) in the first cycle.
- New part inserted in the text:

Immediately after completing the harvest of the first cycle, two harrowing operations were carried out again (medium plow harrow and light leveling harrow), to incorporate residues and level the soil in the area, followed by digging in and then transplanting the seedlings for the second cycle.

The organic matter content of “granular organomineral fertilizer (Org) (formula 05-26-00)” is not provided, which may affect the reader’s understanding of its mechanism of action to some extent（Line 130).
- The following paragraph has been inserted into the text of the article: The granulated organomineral fertilizer (Org) used, based on filter cake, was formula 05-26-00 (N - P - K), which contained 8% total organic carbon (0.14 g dm-3 of organic matter).

 

José Luiz Rodrigues Torres
Corresponding author

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors,

Your manuscript ‘Broccoli cultivation under different sources and rates of specialty phosphorus fertilizers in the Brazilian Cerrado’ is very interesting.

This study aimed to evaluate the agronomic performance and yield of broccoli grown under different sources and rates of specialty phosphorus (P) fertilizers in Uberaba, Minas Gerais, Brazil. The experiment was conducted in a randomized block design arranged in a split-plot scheme, testing three P sources: (1) conventional monoammonium phosphate (CMP); (2) polymer-coated monoammonium phosphate (PCMP); and (3) granular organomineral fertilizer (Org).

Four application rates were evaluated: 0 (no P applied), 50% (200 kg ha⁻¹ of P₂O₅), 75% (300 kg ha⁻¹ of P₂O₅), and 100% (400 kg ha⁻¹ of P₂O₅) of the recommended phosphorus rate for broccoli, with four replications. The parameters assessed included plant nutritional status, soil fertility at harvest, number of leaves (NL), fresh head weight (FHW), dry head weight (DHW), and broccoli yield (YLD). In the first cropping cycle, broccoli showed the highest values for NL (24), FHW 27 (1.05 kg plant⁻¹), DHW (0.27 kg plant⁻¹), and YLD (18.81 Mg ha⁻¹) in the area where PCMP fertilizer was applied.

In the second cropping cycle, the highest NL (23), FHW (1.85 kg plant⁻¹), DHW (0.26 kg plant⁻¹), and YLD (33.01 Mg ha⁻¹) were observed in the area treated with the Org at the 100% rate (400 kg ha⁻¹ of P₂O₅). Broccoli yield in the same area was 124%, 153%, and 115% higher in the second cycle compared to the first for CMP, PCMP, and Org, respectively. The greatest residual effect on soil fertility was observed in the area treated with the Org.

I believe that the manuscript is of potential interest for readers.

My specific comments, that I hope will help the authors to improve the manuscript:

Abstract:

In my opinion it is well structured, and the most important conclusions of the study are well presented there.  

No entanto, as principais conclusões do estudo não são destacadas no final do resumo

 

Introduction:

- the bibliography is appropriate to the topic.

- The introduction is structured with a sequence of information.

- The bibliography used is a little out of date. I suggest changing it to more recent articles

 

Materials and Methods:

-The materials and methods are divided into topics to make it easier for the reader to interpret them.

- A division is made from point 2.1 to 2.5

- In Table 1 I suggest deleting ‘.........’ as it confuses the reader and is not necessary information for understanding the results.

- The legend of Table 1 is divided with the table, I suggest that it be reformulated.

- Figure 2.1 is well presented

- In topic 2.5, which version of the software do you use?

Results and Discussion:

- The results are divided into sections: from point 3.1 to 3.3. It is well written and structured.

- Discuss the results obtained in accordance with more recent and older literature.

- The discussion presents a logical sequence of information

-Tables 2, 3 ... as with the M&Ms, show ‘.......’, which should be removed.

- In table 5, no errors or standard deviation of the results are shown. They should be. The same happens in other tables with similar data.

Conclusions:  

The conclusions are supported by the results presented.

 

References:  

- There are references without a DOI. If possible, they should be included.

Author Response

REVIEWER 3

                                                                                      Uberaba, Minas Gerais, Brazil: 26/05/2025

   Corrections made to the text

 

Abstract:

In my opinion it is well structured, and the most important conclusions of the study are well presented there. 

-The abstract was restructured to include the numerical results at the request of another reviewer.

 

Introduction:

- the bibliography is appropriate to the topic.

- Some more recent studies have been inserted into the text, replacing some older ones

 

- The introduction is structured with a sequence of information.

- Some corrections were made to the introduction at the request of the other reviewers

 

- The bibliography used is a little out of date. I suggest changing it to more recent articles

- Some older articles have been replaced by more recent publications, and some more recent articles have been inserted into the text.

 

Materials and Methods:

- The materials and methods are divided into topics to make it easier for the reader to interpret them.

- A division is made from point 2.1 to 2.5

OK

- In Table 1 I suggest deleting ‘.........’ as it confuses the reader and is not necessary information for understanding the results.

- The points were excluded from the tables.

 

- The legend of Table 1 is divided with the table, I suggest that it be reformulated.

- The reformulation was carried out by inserting the legend at the bottom of the entire table

 

- Figure 2.1 is well presented

- ok

- In topic 2.5, which version of the software do you use?

- Version 2024 - has been inserted into the text.

 

Results and Discussion:

- The results are divided into sections: from point 3.1 to 3.3. It is well written and structured.

- ok

- Discuss the results obtained in accordance with more recent and older literature.

- All points have been removed, as suggested.

 

- The discussion presents a logical sequence of information

-ok

-Tables 2, 3 ... as with the M&Ms, show ‘.......’, which should be removed.

- All points have been removed, as suggested.

 

- In table 5, no errors or standard deviation of the results are shown. They should be. The same happens in other tables with similar data.

- The journal's rules do not require the inclusion of errors and standard deviations in the tables, which is why they do not appear.

Conclusions: 

 

The conclusions are supported by the results presented.

ok

 References: 

- There are references without a DOI. If possible, they should be included.

- The DOI was added to all the articles that had this reference.

 

            I would like to thank the reviewer for his suggestions on improving the quality of the article, all of which have been taken on board and inserted into the body of the text:

 

 

__________________________

José Luiz Rodrigues Torres

Corresponding author

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Lines 105 and 106: It is recommended that the authors use metric units; for instance, all measurements currently presented in inches should be converted to the metric system (e.g., centimeters or millimeters) in accordance with international scientific standards.

Author Response

Second round of corrections:

 Comments and Suggestions for Authors:

Lines 105 and 106: It is recommended that the authors use metric units; for instance, all measurements currently presented in inches should be converted to the metric system (e.g., centimeters or millimeters) in accordance with international scientific standards.

 original text:

Two disking operations were carried out: a deep disking using a harrow with 18 discs (30 inches in diameter), followed by a superficial disking with a light harrow equipped with 44 discs (24 inches in diameter).

 

Corrected text:

Two disking operations were carried out: a deep disking using a harrow with 18 discs (76.2 cm in diameter), followed by a superficial disking with a light harrow equipped with 44 discs (60.96 cm in diameter).

             I would like to thank the reviewer for his suggestions on improving the quality of the article, all of which have been taken on board and inserted into the body of the text: