DMPP and Polymer-Coated Urea Promoted Growth and Increased Yield of Greenhouse Tomatoes

Round 1

Reviewer 1 Report

Dear Editor,

 

In this work, the authors reported the effects of two urea types provided with different strategies (i.e., nitrification inhibitors (DMPP+urea), and slow-release (polymer-coated urea)), and N application rates, on the growth factors and the yield of tomato in the greenhouse. The study is well planned and the subject is attractive to the Journal’s readers. In my opinion, the manuscript can be published after revision based on the following comments.

 

• The authors should define the abbreviation of DMPP in the Abstract.
• The authors should add a phrase for introducing their urea treatments in the Abstract.
• The authors should improve the literature and use the other latest publications in this field. Just as an example: “Synthesis of urea slow-release fertilizer using a novel starch-g-poly(styrene-co-butylacrylate) nanocomposite latex and its impact on a model crop production in greenhouse”, Journal of Cleaner Production (2021) 322, 129082.
• The authors should ensure uniformity for the tenses (past/present) in the whole manuscript.
• English has to be improved a lot, some comments were provided in the attached file.
• Elaborate on the discussion.
• It would be more interesting for readers if the authors provide some charts/Figs rather than Tables to present their results.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The subject addressed by the authors is of interest to readers of Horticulturae; however, the quality of the work and of the manuscript is not such as to justify its publication. My advice is therefore to reject the manuscript and to invite the authors to submit a new manuscript after a careful revision based on the following comments:

1) A thorough revision of the English language is required.

2) Statistics. The authors conducted an analysis of variance that does not allow to separate the mean values of the treatments including among them the control (non-fertilized crop). The tables should present the mean values ​​(±standard error) of the three nitrogen doses, of the three types of urea used, and of the nine treatments originating from the combination of nitrogen levels and urea types; therefore, mean separation among N levels, ureà types, and their interactions will be carried out only in the case of a significant value of F. The same table will report the mean values ​​(+ standard error) of the control and, to compare the control with the other nine treatments, the Student's t-test will be used; an asterisk will indicate the mean values ​​that significantly differed from the control.

3) The authors did not report the values ​​of the main climatic variables (temperature, relative humidity, and average and cumulative solar radiation) recorded in the two experiments conducted in 2020 and 2021, nor the mineral content of the soil in the second year. In the Discussion (lines 368-370), climatic conditions are brought up to explain some findings.

4) The two experiments were conducted in a soil rich in available nitrogen and phosphorus, and relatively poor in available K, which is an important element for tomato yield and quality. The authors must take this fact into account when presenting the work and discussing the results.

5) Crop yield: total and marketable yield, and the number and mean size of fresh tomatoes are important data that the Authors should report in the manuscript.

Minor comments:

- Nutrient use efficiency. A more appropriate term for the index calculated by the Authors is ‘agronomic efficiency’ (see Congreves et al., 2021, https://www.frontiersin.org/articles/10.3389/fpls.2021.637108/full)

- The meaning of the abbreviations and the units of measurement must be reported in the captions of the figures and tables.

- The Authors must be consistent in the use of abbreviations because some parameters are sometimes reported with the full name, other times using the abbreviation. A table with the meaning of the abbreviations would be useful for the reader.

- Tables 7 and 8. What do W1, W2 and W3 mean? Do they mean the sampling date, i.e. 30, 60 and 90 days from the transplant?

- Discussion, line 323. The Authors state: "Under T3, the leaching of N was reduced due to the effect of DMPP, which promoted the development of the root system of greenhouse tomato". Howeverm in the experiments there was no nitrogen leaching as the percolation of the water was nil, as stated in lines 150-151.

- Some parameters (e.g., plant height and stem diameter) are of minor importance and could be reported as supplementary material.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Dear Editor,

The authors have performed revision of their work thoroughly considering the suggestions of the Reviewer. Suggested changes were incorporated and questions were answered properly. In the present form, the paper could be accepted.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The quality of the manuscript was significantly improved by the Authors, who followed almost all the referee’s comments and suggestions. However, minor revision is still necessary.

The main deficiency of this manuscript concerns the statistical analysis:

• In section 2.4, the Authors must report how they analyzed the data and separated the mean values (ANOVA, Tukey’s test, Student’s test).
• In all the tables: i) the standard deviation must be replaced by the standard error and the number of samples (N) must be shown; 2) the mean values of the control treatment cannot be followed by letters as it was compared with other treatments using the Student’s test for each pair; 3) it is necessary to add neither ‘NS’ when the difference between the treatment and the control was not significant, nor three ‘A’ when the mean effect of nitrogen application rate or urea type was not significant; this will make the tables easier to read.

Figures 1 and 2 should be omitted. I understand that the Authors followed one of the comments of the other referee. However, the table reported in the previous manuscript is much easier to read.

The Authors must be consistent with the captions of tables and figures. Sometimes they use ‘N fertilisation strategy’, sometimes ‘N application rate and urea type’, which I prefer.

In the Discussion:

• Rows 453-459: The Authors did not consider the high soil N content and ascribed the non-linear response of total fruit yield (and marketable yield as well) to N application only to the low soil K content. They should also add ‘marketable fruit yield’
• Rows 462-465: The Authors cite the occurrence of both biotic and abiotic stress, which would have had to be very severe to override the effects of the treatments under study and thus would have invalidated the whole study. This sentence should be deleted.

Author Response

Please see the attachment.

Author Response File: Author Response.docx