Combined Effects of Induced Water Deficit and Foliar Application of Silicon on the Gas Exchange of Tomatoes for Processing
, Marcio Mesquita 1,*, Amanda Magalhães Bueno 1, Rilner Alves Flores 1, Henrique Fonseca Elias de Oliveira 2, Frederico Simões Raimundo de Lima 1, Renato de Mello Prado 3 and Rafael Battisti 1
Round 1
Reviewer 1 Report
The paper presents the results of a sound and interesting experiment. The work does not add much to current knowledge, but without any doubt it can be of wide interest to the readers. The references quoted by the Authors all well chosen, and the bibliography is wide. The presentation of resuls is also clear. Yet, some major flaws suggest to submit the paper to a major revision.
In fact, the English form should be thoroughly controlled, possibly by a mothertongue.
In the presentation of results, I would suggest to show the results first (Table 2, Figures 1, 2, 3, 4) and later the analysis of variance (tables 1 and 3): in my opinion, this would make the paper more readable. The captions of Tables 1 and 3 could be a bit expanded to make them more clear.
The Discussion is very wide, but it includes much state-of-art, that could be transferred, at least in part, to the Introduction, focusing more on the results here presented. The Conclusions on the contrary could be expanded, to summarize more clearly the output of the experiment.
Author Response
1) The paper presents the results of a sound and interesting experiment. The work does not add much to current knowledge, but without any doubt it can be of wide interest to the readers. The references quoted by the Authors all well chosen, and the bibliography is wide. The presentation of resuls is also clear. Yet, some major flaws suggest to submit the paper to a major revision.
Answer: There were significant changes in the presentation of results and discussion for a better representation of information
2) In fact, the English form should be thoroughly controlled, possibly by a mothertongue.
Answer: This suggestion must be answered by resending for a new revision of English by the company previously hired.
3) In the presentation of results, I would suggest to show the results first (Table 2, Figures 1, 2, 3, 4) and later the analysis of variance (tables 1 and 3): in my opinion, this would make the paper more readable. The captions of Tables 1 and 3 could be a bit expanded to make them more clear.
Answer: Lines 139-319: Table 2 was replaced by the current Figure 1 and added to the supplementary material. The order of Figures 3, 4, and 5 have not been changed, as they are referenced in the current Table 2. If these results were reversed in the presentation, the figures would appear before the table.
4) The Discussion is very wide, but it includes much state-of-art, that could be transferred, at least in part, to the Introduction, focusing more on the results here presented. The Conclusions on the contrary could be expanded, to summarize more clearly the output of the experiment.
Answer: Lines 323-329: The discussion was reduced, but the conclusion was not altered because we briefly describe the answers found in the work. Remembering that the conclusion section is not mandatory: "this section is not mandatory, but can be added to the manuscript if the discussion is extraordinarily long or complex".
Author Response File: 
Author Response.docx
Reviewer 2 Report
The paper presents result on the possible effect of Si on tomato plants subjected to two water availability during the growth and production. The subject of the research is interesting. Nevertheless, at the present there are many points that have to be clarified and consequently modified. Some of these points are important and consequently the paper cannot be published. In additions there are also many minor observations.
My major objection concerns the treatment with Si:
-line 83 and followings, the content of the solution used for the foliar spry is not defined.
The chemical form of Si should be clearly indicated, the concentrations should be presented in molarity. I suppose that the highest concentrations indicated: Si 3,82 M, and Cu is O,23 M, do not refer to the spry solution, but that this is more diluted. This should be clarified. The solution contains also Cu: how is it possible to exclude that the effects described do not depends on the presence of Cu. The pH of solutions is very basic: this do not produce damage to the leafs. The controls should be sprayed with a similar solution not containing Si. The sentence line 85: “Each…” is obscure. Even if in the control spry solution is similar without Si the effect of Si in plants in the presence of Cu should discussed.
How the foliar spray is made? How much is the volume of spray for each plant? The possibility that this solution goes into the soil must be excluded.
The abstract should be rewritten introducing the results.
-line 18 see previous observation
-line 20 “better rate” of gas exchange: the results should be introduced
-line 26 “promote improvement of gas exchange” the results should be introduced.
-line 68 It is better to introduce in the title the name of cultivar.
The plants are not grown in a greenhouse: “..environment with controlled temperature..” is not controlled but probably monitored. The temperature (min e max) humidity, and light should be introduced.
-lines 105; 111 the statistical analysis appears well done but I think that the tables 1,2 e 3 should be better presented and discussed, in particular which and how many numbers are used.
-the figures: The results presented in the figure are interpolated in a function (solid or dotted lines) that often do not fit appropriately (R2) . I do not think that it should be useful introduce this elaboration. It is possible that in some case there is a threshold value, and the results can not be presented as a continuous function.
In generally the manuscript needs a general accurate check, also reducing the discussion to only significant results.
Author Response
1) The paper presents result on the possible effect of Si on tomato plants subjected to two water availability during the growth and production. The subject of the research is interesting. Nevertheless, at the present there are many points that have to be clarified and consequently modified. Some of these points are important and consequently the paper cannot be published. In additions there are also many minor observations.
Answer: There were significant changes in the presentation of results and discussion for a better representation of information
2) line 83 and followings, the content of the solution used for the foliar spry is not defined.
Answer: Lines 93-108: Leaf sprays containing Si were carried out with stabilized alkaline silicate (Si = 107 g L-1, K2O = 28.4 g L-1, Cu = 14.9 g L-1, pH = 11.5). Doses of 0.0 (control), 1.0, 2.0, 3.0, and 4.0 g L-1 of silicon were applied, divided into three applications at 15, 29, and 43 days after transplantation (DAT), that is, the initial, intermediate, and final flowering periods, respectively. Each applied Si dose was balanced with K and Cu using K2O and Cu2O so that the spraying effect was influenced only by Si.
3) The chemical form of Si should be clearly indicated, the concentrations should be presented in molarity. I suppose that the highest concentrations indicated: Si 3,82 M, and Cu is O,23 M, do not refer to the spry solution, but that this is more diluted. This should be clarified. The solution contains also Cu: how is it possible to exclude that the effects described do not depends on the presence of Cu. The pH of solutions is very basic: this do not produce damage to the leafs. The controls should be sprayed with a similar solution not containing Si. The sentence line 85: “Each…” is obscure. Even if in the control spry solution is similar without Si the effect of Si in plants in the presence of Cu should discussed.
Answer: All applied doses (0, 1, 2, 3 and 4 g L-1) were balanced with K (K2O) and Cu (Cu2O). Thus, all doses (even the control treatment) had the same concentrations of these nutrients and the observed effect was only for silicon. Line 84: Leaf sprays containing Si were carried out with stabilized alkaline silicate (Si = 107 g L-1 (3.81 M), K2O = 28.4 g L-1 (0.73 M), Cu = 14.9 g L-1 (0.23 M), pH = 11.5). Doses of 0.0 (control), 1.0, 2.0, 3.0, and 4.0 g L-1 of silicon were applied, divided into three applications at 15, 29, and 43 days after transplantation (DAT), that is, initial, intermediate, and final flowering periods, respectively. The sprayings of the total doses were divided into parts so that the product did not promote a phytotoxic effect on tomatoes. At the time of application, the soil was covered with a plastic tarpaulin so that it was not contaminated. Each applied Si dose was balanced with K and Cu using K2O and Cu2O so that only the Si content was a factor of variation. Thus, all doses contained the concentration of K2O and Cu, being 0.011 M and 0.0088 M, respectively.
4) How the foliar spray is made? How much is the volume of spray for each plant? The possibility that this solution goes into the soil must be excluded.
Answer: Line 100: A 50 mL of the solution was applied per plant, representative of the volume, one application was considered uniform, covering the entire area of the plant. At the time of application, the soil was covered with a plastic tarpaulin so that it was not contaminated.
5) The abstract should be rewritten introducing the results. line 18 see previous observation. Line 20 “better rate” of gas exchange: the results should be introduced, line 26 “promote improvement of gas exchange” the results should be introduced.
Answer: The abstract has been rewritten
6) Line 68 It is better to introduce in the title the name of cultivar.
Answer: The abstract has been rewritten
7) The plants are not grown in a greenhouse: “. environment with controlled temperature...” is not controlled but probably monitored. The temperature (min e max) humidity, and light should be introduced.
Answer: Lines 71- 79:A hybrid cultivar of tomato Nunhems 901 (N-901) grown in a protected environment, with temperature (minimum and maximum) and relative humidity (%) monitored, in the municipality of Goiânia-Goiás-Brazil (16 ° 35 'N, 49 ° 21 'W, altitude 724 m). According to Köppen, the region has a tropical savanna climate with dry winter and rainy summer (Aw) (Alvares et al., 2013).
8) Lines 105; 111 the statistical analysis appears well done but I think that the tables 1,2 e 3 should be better presented and discussed, in particular which and how many numbers are used.
Answer: Some of the tables have been moved to supplementary material to highlight the really important results
9) The figures: The results presented in the figure are interpolated in a function (solid or dotted lines) that often do not fit appropriately (R). I do not think that it should be useful introduce this elaboration. It is possible that in some case there is a threshold value, and the results can not be presented as a continuous function.
Answer: We reviewed all the statistics and even some results obtained, we observed that some coefficients of determination (R2) did not have enough value to explain the behavior of the equation.
10) In generally the manuscript needs a general accurate check, also reducing the discussion to only significant results.
Answer: The discussion was reduced, the paragraph between lines 323-329 was removed and there was a general readjustment of the words used and revision of English in order to improve the understanding of the results.
Author Response File: Author Response.docx
Round 2
Reviewer 2 Report
The author have substantially implemented the suggestions and objections and have consequently modified the manuscript by also introducing some of the required clarification required.
